A nutrient is a substance, typically contained in food, which is used by an organism to grow or maintain health or for energy. The Nutrient type includes macronutrients and micronutrients, as well as categories of nutrients (such as carbohydrate or fat), and both essential and inessential nutrients.
More about Best Nutrient of All Time:
Best Nutrient of All Time is a public top list created by Listnerd on Rankly.com on November 27th 2012. Items on the Best Nutrient of All Time top list are added by the Rankly.com community and ranked using our secret ranking sauce. Best Nutrient of All Time has gotten 634 views and has gathered 348 votes from 348 voters. Only owner can add items. Just members can vote.
Best Nutrient of All Time is a top list in the Food & Drinks category on Rankly.com. Are you a fan of Food & Drinks or Best Nutrient of All Time? Explore more top 100 lists about Food & Drinks on Rankly.com or participate in ranking the stuff already on the all time Best Nutrient of All Time top list below.
If you're not a member of Rankly.com, you should consider becoming one. Registration is fast, free and easy. At Rankly.com, we aim to give you the best of everything - including stuff like the Best Nutrient of All Time list.
Get your friends to vote! Spread this URL or share:
Riboflavin, also known as vitamin B2 is an easily absorbed colored micronutrient with a key role in maintaining health in humans and animals. It is the central component of the cofactors FAD and FMN, and is therefore required by all flavoproteins. As such, vitamin B2 is required for a wide variety of cellular processes. It plays a key role in energy metabolism, and for the metabolism of fats, ketone bodies, carbohydrates, and proteins.
Milk, cheese, leaf vegetables, liver, kidneys, legumes, yeast, mushrooms, and almonds are good sources of vitamin B2, but exposure to light destroys riboflavin.
The name "riboflavin" comes from "ribose" (the sugar whose reduced form, ribitol, forms part of its structure) and "flavin", the ring-moiety which imparts the yellow color to the oxidized molecule (from Latin flavus, "yellow"). The reduced form, which occurs in metabolism along with the oxidized form, is colorless.
Riboflavin is best known visually as the vitamin which imparts the orange color to solid B-vitamin preparations, the yellow color to vitamin supplement solutions, and the unusual fluorescent-yellow color to the urine of persons who supplement with high-dose B-complex preparations
Glutamic acid (abbreviated as Glu or E) is one of the 20-22 proteinogenic amino acids, and its codons are GAA and GAG. It is a non-essential amino acid. The carboxylate anions and salts of glutamic acid are known as glutamates. In neuroscience, glutamate is an important neurotransmitter that plays a key role in long-term potentiation and is important for learning and memory.
The side chain carboxylic acid functional group has a pKa of 4.1 and exists in its negatively charged deprotonated carboxylate form at pHs greater than 4.1 therefore it is also negatively charged at physiological pH ranging from 7.35 to 7.45.
Although they occur naturally in many foods, the flavor contributions made by glutamic acid and other amino acids were only scientifically identified early in the twentieth century. The substance was discovered and identified in the year 1866, by the German chemist Karl Heinrich Leopold Ritthausen who treated wheat gluten (for which it was named) with sulfuric acid. In 1907 Japanese researcher Kikunae Ikeda of the Tokyo Imperial University identified brown crystals left behind after the evaporation of a large amount of kombu broth as glutamic acid. These crystals, when
Fructose or fruit sugar, is a simple monosaccharide found in many plants. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorbed directly into the bloodstream during digestion. Fructose was discovered by French chemist Augustin-Pierre Dubrunfaut in 1847. Pure, dry fructose is a very sweet, white, odorless, crystalline solid and is the most water-soluble of all the sugars. From plant sources, fructose is found in honey, tree and vine fruits, flowers, berries, and most root vegetables. In plants, fructose may be present as the monosaccharide and/or as a molecular component of sucrose, which is a disaccharide.
Commercially, fructose frequently is derived from sugar cane, sugar beets, and corn and there are three commercially important forms. Crystalline fructose is the monosaccharide, dried, ground, and of high purity. The second form, high-fructose corn syrup (HFCS) is a mixture of glucose and fructose as monosaccharides. The third form, sucrose, is a compound with one molecule of glucose covalently linked to one molecule of fructose. All forms of fructose, including fruits and juices, are commonly added to foods and drinks for
"Niacin" redirects here. For the neo-fusion band, see Niacin (band).
Niacin (also known as vitamin B3, nicotinic acid and vitamin PP) is an organic compound with the formula C6H5NO2 and, depending on the definition used, one of the forty to eighty essential human nutrients.
Niacin is one of five vitamins (when lacking in human diet) associated with a pandemic deficiency disease: niacin deficiency (pellagra), vitamin C deficiency (scurvy), thiamin deficiency (beriberi), vitamin D deficiency (rickets), vitamin A deficiency (night blindness and other symptoms). Niacin has been used for over 50 years to increase levels of HDL in the blood and has been found to modestly decrease the risk of cardiovascular events in a number of controlled human trials.
This colorless, water-soluble solid is a derivative of pyridine, with a carboxyl group (COOH) at the 3-position. Other forms of vitamin B3 include the corresponding amide, nicotinamide ("niacinamide"), where the carboxyl group has been replaced by a carboxamide group (CONH2), as well as more complex amides and a variety of esters.
Niacin cannot be directly converted to nicotinamide, but both compounds could be converted to NAD and NADP in
Lycopene (from the New Latin word lycopersicum for the tomato species name) is a bright red carotene and carotenoid pigment and phytochemical found in tomatoes and other red fruits and vegetables, such as red carrots, red bell peppers, watermelons, and papayas (but not strawberries or cherries). Although lycopene is chemically a carotene, it has no vitamin A activity.
In plants, algae, and other photosynthetic organisms, lycopene is an important intermediate in the biosynthesis of many carotenoids, including beta carotene, responsible for yellow, orange or red pigmentation, photosynthesis, and photo-protection. Like all carotenoids, lycopene is a polyunsaturated hydrocarbon (an unsubstituted alkene). Structurally, it is a tetraterpene assembled from eight isoprene units, composed entirely of carbon and hydrogen, and is insoluble in water. Lycopene's eleven conjugated double bonds give it its deep red color and are responsible for its antioxidant activity. Due to its strong color and non-toxicity, lycopene is a useful food coloring (registered as E160d) and is approved for usage in the USA, Australia and New Zealand (registered as 160d) and the EU.
Lycopene is not an essential
Selenium (/sɨˈliːniəm/ sə-LEE-nee-əm) is a chemical element with symbol Se and atomic number 34. It is a nonmetal with properties that are intermediate between those of its periodic table column-adjacent chalcogen elements sulfur and tellurium. It rarely occurs in its elemental state in nature, or as pure ore compounds. Selenium (Greek σελήνη selene meaning "Moon") was discovered in 1817 by Jöns Jakob Berzelius, who noted the similarity of the new element to the previously-known tellurium (named for the Earth).
Selenium is found impurely in metal sulfide ores, where it partially replaces the sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores, most often during copper production. Minerals that are pure selenide or selenate compounds are known, but are rare. The chief commercial uses for selenium today are in glassmaking and in pigments. Selenium is a semiconductor and is used in photocells. Uses in electronics, once important, have been mostly supplanted by silicon semiconductor devices. Selenium continues to be used in a few types of DC power surge protectors and one type of fluorescent quantum dot.
Selenium salts are toxic in large amounts, but
Isoleucine (abbreviated as Ile or I) is an α-amino acid with the chemical formula HO2CCH(NH2)CH(CH3)CH2CH3. It is an essential amino acid, which means that humans cannot synthesize it, so it must be ingested. Its codons are AUU, AUC and AUA.
With a hydrocarbon side chain, isoleucine is classified as a hydrophobic amino acid. Together with threonine, isoleucine is one of two common amino acids that have a chiral side chain. Four stereoisomers of isoleucine are possible, including two possible diastereomers of L-isoleucine. However, isoleucine present in nature exists in one enantiomeric form, (2S,3S)-2-amino-3-methylpentanoic acid.
As an essential amino acid, isoleucine is not synthesized in animals, hence it must be ingested, usually as a component of proteins. In plants and microorganisms, it is synthesized via several steps, starting from pyruvic acid and alpha-ketoglutarate. Enzymes involved in this biosynthesis include:
Isoleucine is both a glucogenic and a ketogenic amino acid. After transamination with alpha-ketoglutarate the carbon skeleton can be converted into either Succinyl CoA, and fed into the TCA cycle for oxidation or conversion into oxaloacetate for gluconeogenesis
Sodium ( /ˈsoʊdiəm/ SOH-dee-əm) is a chemical element with the symbol Na (from Latin: natrium) in the periodic table and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is Na. The free metal does not occur in nature, but instead must be prepared from its compounds; it was first isolated by Humphry Davy in 1807 by the electrolysis of sodium hydroxide. Sodium is the sixth most abundant element in the Earth's crust, and exists in numerous minerals such as feldspars, sodalite and rock salt. Many salts of sodium are highly water-soluble, and their sodium has been leached by the action of water so that chloride and sodium are the most common dissolved elements by weight in the Earth's bodies of oceanic water.
Many sodium compounds are useful, such as sodium hydroxide (lye) for soapmaking, and sodium chloride for use as a deicing agent and a nutrient (edible salt). Sodium is an essential element for all animals and some plants. In animals, sodium ions are used against potassium ions to build up charges on cell membranes, allowing transmission of nerve impulses when the charge is dissipated. The consequent
A carbohydrate is an organic compound that consists only of carbon, hydrogen, and oxygen, usually with a hydrogen:oxygen atom ratio of 2:1 (as in water); in other words, with the empirical formula Cm(H2O)n. (Some exceptions exist; for example, deoxyribose, a component of DNA, has the empirical formula C5H10O4.) Carbohydrates are not technically hydrates of carbon. Structurally it is more accurate to view them as polyhydroxy aldehydes and ketones.
The term is most common in biochemistry, where it is a synonym of saccharide. The carbohydrates (saccharides) are divided into four chemical groupings: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. In general, the monosaccharides and disaccharides, which are smaller (lower molecular weight) carbohydrates, are commonly referred to as sugars. The word saccharide comes from the Greek word σάκχαρον (sákkharon), meaning "sugar." While the scientific nomenclature of carbohydrates is complex, the names of the monosaccharides and disaccharides very often end in the suffix -ose. For example, blood sugar is the monosaccharide glucose, table sugar is the disaccharide sucrose, and milk sugar is the disaccharide lactose (see
A naturally-occurring form of vitamin E, a fat-soluble vitamin with potent antioxidant properties. Considered essential for the stabilization of biological membranes (especially those with high amounts of polyunsaturated fatty acids), d-alpha-Tocopherol is a potent peroxyl radical scavenger and inhibits noncompetitively cyclooxygenase activity in many tissues, resulting in a decrease in prostaglandin production. Vitamin E also inhibits angiogenesis and tumor dormancy through suppressing vascular endothelial growth factor (VEGF) gene transcription. (NCI04)
Linoleic acid is a doubly unsaturated fatty acid, also known as an omega-6 fatty acid, occurring widely in plant glycosides. In this particular polyunsaturated fatty acid (PUFA), the first double bond is located between the sixth and seventh carbon atom from the methyl end of the fatty acid (n-6). Linoleic acid is an essential fatty acid in human nutrition because it cannot be synthesized by humans. It is used in the biosynthesis of prostaglandins (via arachidonic acid) and cell membranes. (From Stedman, 26th ed)
Stigmasterol (also known as Wulzen anti-stiffness factor) is one of a group of plant sterols, or phytosterols, that include β-sitosterol, campesterol, ergosterol (provitamin D2), brassicasterol, delta-7-stigmasterol and delta-7-avenasterol, that are chemically similar to animal cholesterol. Phytosterols are insoluble in water but soluble in most organic solvents and contain one alcohol functional group.
Stigmasterol is an unsaturated plant sterol occurring in the plant fats or oils of soybean, calabar bean, and rape seed, and in a number of medicinal herbs, including the Chinese herbs Ophiopogon japonicus (Mai men dong) and American Ginseng. Stigmasterol is also found in various vegetables, legumes, nuts, seeds, and unpasteurized milk. Pasteurization will inactivate stigmasterol. Edible oils contains higher amount than vegetables. Phytosterols normally are broken down in the bile.
Stigmasterol is used as a precursor in the manufacture of semisynthetic progesterone, a valuable human hormone that plays an important physiological role in the regulatory and tissue rebuilding mechanisms related to estrogen effects, as well as acting as an intermediate in the biosynthesis of androgens,
Serine (abbreviated as Ser or S) is an amino acid with the formula HO2CCH(NH2)CH2OH. It is one of the proteinogenic amino acids. Its codons in the genetic code are UCU, UCC, UCA, UCG, AGU and AGC. By virtue of the hydroxyl group, serine is classified as a polar amino acid.
This compound is one of the naturally occurring proteinogenic amino acids. Only the L-stereoisomer appears naturally in proteins. It is not essential to the human diet, since it is synthesized in the body from other metabolites, including glycine. Serine was first obtained from silk protein, a particularly rich source, in 1865. Its name is derived from the Latin for silk, sericum. Serine's structure was established in 1902.
The biosynthesis of serine starts with the oxidation of 3-phosphoglycerate to 3-phosphohydroxypyruvate and NADH. Reductive amination of this ketone followed by hydrolysis gives serine. Serine hydroxymethyltransferase catalyzes the reversible, simultaneous conversions of L-serine to glycine (retro-aldol cleavage) and 5,6,7,8-tetrahydrofolate to 5,10-methylenetetrahydrofolate (hydrolysis).
This compound may also be naturally produced when UV light illuminates simple ices such as a combination of
Thiamine or thiamin or vitamin B1 ( /ˈθaɪ.əmɨn/ THY-ə-min), named as the "thio-vitamine" ("sulfur-containing vitamin") is a water-soluble vitamin of the B complex. First named aneurin for the detrimental neurological effects if not present in the diet, it was eventually assigned the generic descriptor name vitamin B1. Its phosphate derivatives are involved in many cellular processes. The best-characterized form is thiamine pyrophosphate (TPP), a coenzyme in the catabolism of sugars and amino acids. Thiamine is used in the biosynthesis of the neurotransmitter acetylcholine and gamma-aminobutyric acid (GABA). In yeast, TPP is also required in the first step of alcoholic fermentation.
All living organisms use thiamine in their biochemistry, but it is synthesized only in bacteria, fungi, and plants. Animals must obtain it from their diet, and thus, for them, it is an essential nutrient. Insufficient intake in birds produces a characteristic polyneuritis. In mammals, deficiency results in Korsakoff's syndrome, optic neuropathy, and a disease called beriberi that affects the peripheral nervous system (polyneuritis) and/or the cardiovascular system. Thiamine deficiency has a potentially
Vitamin A (or Vitamin A Retinol, retinal, and four carotenoids including beta carotene) is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal, that is necessary for both low-light (scotopic vision) and color vision. Vitamin A also functions in a very different role as an irreversibly oxidized form of retinol known as retinoic acid, which is an important hormone-like growth factor for epithelial and other cells.
In foods of animal origin, the major form of vitamin A is an ester, primarily retinyl palmitate, which is converted to retinol (chemically an alcohol) in the small intestine. The retinol form functions as a storage form of the vitamin, and can be converted to and from its visually active aldehyde form, retinal. The associated acid (retinoic acid), a metabolite that can be irreversibly synthesized from vitamin A, has only partial vitamin A activity, and does not function in the retina for the visual cycle.
All forms of vitamin A have a beta-ionone ring to which an isoprenoid chain is attached, called a retinyl group. Both structural features are essential for vitamin activity. The orange pigment of
Alanine (abbreviated as Ala or A) is an α-amino acid with the chemical formula CH3CH(NH2)COOH. The L-isomer is one of the 20 amino acids encoded by the genetic code. Its codons are GCU, GCC, GCA, and GCG. It is classified as a nonpolar amino acid. L-Alanine is second only to leucine in rate of occurrence, accounting for 7.8% of the primary structure in a sample of 1,150 proteins. D-Alanine occurs in bacterial cell walls and in some peptide antibiotics.
The α-carbon atom of alanine is bound with a methyl group (-CH3), making it one of the simplest α-amino acids with respect to molecular structure and also resulting in alanine's being classified as an aliphatic amino acid. The methyl group of alanine is non-reactive and is thus almost never directly involved in protein function.
Alanine is a nonessential amino acid, meaning it can be manufactured by the human body, and does not need to be obtained directly through the diet. Alanine is found in a wide variety of foods, but is particularly concentrated in meats.
Good sources of alanine include
Alanine can be manufactured in the body from pyruvate and branched chain amino acids such as valine, leucine, and isoleucine.
Alanine is most
Myristoleic acid, or 9-tetradecenoic acid, is an omega-5 fatty acid. It is biosynthesized from myristic acid by the enzyme delta-9 desaturase, but it is uncommon in nature. One of the major sources of this fatty acid is the seed oil from plants of the genus Myristicaceae, comprising up to 30 per cent of the oil in some species.
The cetyl ester of myristoleic acid has biological properties as an anti-inflammatory, a pain reliever, and an immune system modulator. (See cetyl myristoleate)
A member of the vitamin B family that stimulates the hematopoietic system. It is present in the liver and kidney and is found in mushrooms, spinach, yeast, green leaves, and grasses (POACEAE). Folic acid, being biochemically inactive, is converted to tetrahydrofolic acid and methyltetrahydrofolate by dihydrofolate reductase. These folic acid congeners are transported across cells by receptor-mediated endocytosis where they are needed to maintain normal erythropoiesis, synthesize purine and thymidylate nucleic acids, interconvert amino acids, methylate tRNA, and generate and use formate. Folic acid is used in the treatment and prevention of folate deficiencies and megaloblastic anemia.
Leucine (abbreviated as Leu or L) is a branched-chain α-amino acid with the chemical formula HO2CCH(NH2)CH2CH(CH3)2. Leucine is classified as a hydrophobic amino acid due to its aliphatic isobutyl side chain. It is encoded by six codons (UUA, UCG, CUU, CUC, CUA, and CUG) and is a major component of the subunits in ferritin, astacin and other 'buffer' proteins. Leucine is an essential amino acid, meaning that the human body cannot synthesize it, and it therefore must be ingested.
As an essential amino acid, leucine cannot be synthesised by animals. Consequently, it must be ingested, usually as a component of proteins. In plants and microorganisms, leucine is synthesised from pyruvic acid by a series of enzymes:
Synthesis of the small, hydrophobic amino acid Valine also includes the initial part of this pathway.
Leucine is utilized in the liver, adipose tissue, and muscle tissue. In adipose and muscle tissue, leucine is used in the formation of sterols, and the combined usage of leucine in these two tissues is seven times greater than its use in the liver.
Leucine is the only dietary amino acid that has the capacity to stimulate muscle protein synthesis. As a dietary supplement,
Palmitic acid, or hexadecanoic acid is one of the most common saturated fatty acids found in animals and plants, a saturated fatty acid found in fats and waxes including olive oil, palm oil, and body lipids.(wikipedia) Biological Source: Occurs in the form of esters (glycerides) in oils and fats of vegetable and animal origin. Usually obt. from palm oil. Widely distributed in plants Use/Importance: Used in detn. of water hardness Biological Use/Importance: Active ingredient of *Levovist*TM, used in echo enhancement in sonographic Doppler B-mode imaging. Ultrasound contrast medium (Dictionary of Organic Compounds)
Zinc (/ˈzɪŋk/ ZINGK; from German: Zink), or spelter (which may also refer to zinc alloys), is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element of group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2. Zinc is the 24th most abundant element in the Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest mineable amounts are found in Australia, Asia, and the United States. Zinc production includes froth flotation of the ore, roasting, and final extraction using electricity (electrowinning).
Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC. Impure zinc metal was not produced in large scale until the 13th century in India, while the metal was unknown to Europe until the end of the 16th century. Alchemists burned zinc in air to form what they called "philosopher's wool" or "white snow".
The element was probably named by the alchemist Paracelsus after the German word Zinke. German chemist Andreas Sigismund
Behenic acid, also docosanoic acid, is a normal carboxylic acid, a fatty acid with formula C21H43COOH. -- Wikipedia; It is an important constituent of the behen oil extracted from the seeds of the Ben-oil tree, and it is so named from the Persian month Bahman when the roots of this tree were harvested. -- Wikipedia
Lutein and zeaxanthin are the only carotenoids found in the retina and lens of the eye. The results of epidemiological studies suggest that diets rich in lutein and zeaxanthin may help slow the development of age-related macular degeneration and cataracts, but it is not known whether lutein and zeaxanthin supplements will slow the development of these age-related eye diseases. A clinical trial, the Age-related Eye Disease Study 2 (AREDS2), is currently under way to evaluate the effect of supplemental lutein and zeaxanthin on the progression of advanced AMD. To date, the available scientific evidence suggests that consuming at least 6 mg/day of dietary lutein and zeaxanthin from fruits and vegetables may decrease the risk of age-related macular degeneration. (Source - http://lpi.oregonstate.edu/infocenter/phytochemicals/carotenoids )
Pantothenic acid, also called pantothenate or vitamin B5 (a B vitamin), is a water-soluble vitamin discovered by Roger J. Williams in 1919. For many animals, pantothenic acid is an essential nutrient. Animals require pantothenic acid to synthesize coenzyme-A (CoA), as well as to synthesize and metabolize proteins, carbohydrates, and fats.
Pantothenic acid is the amide between pantoic acid and β-alanine. Its name derives from the Greek pantothen (πάντοθεν) meaning "from everywhere" and small quantities of pantothenic acid are found in nearly every food, with high amounts in whole-grain cereals, legumes, eggs, meat, royal jelly, avocado, and yogurt. It is commonly found as its alcohol analog, the provitamin panthenol, and as calcium pantothenate. Pantothenic acid is an ingredient in some hair and skin care products.
Only the dextrorotatory (D) isomer of pantothenic acid possesses biologic activity. The levorotatory (L) form may antagonize the effects of the dextrorotatory isomer.
Pantothenic acid is used in the synthesis of coenzyme A (CoA). Coenzyme A may act as an acyl group carrier to form acetyl-CoA and other related compounds; this is a way to transport carbon atoms within the
Stearic acid, also called octadecanoic acid, is one of the useful types of saturated fatty acids that comes from many animal and vegetable fats and oils. It is a waxy solid, and its chemical formula is CH3(CH2)16COOH. Its name comes from the Greek word stear, which means tallow. Its IUPAC name is octadecanoic acid. -- Wikipedia
Choline is a water-soluble essential nutrient. It is usually grouped within the B-complex vitamins. Choline generally refers to the various quaternary ammonium salts containing the N,N,N-trimethylethanolammonium cation. (X on the right denotes an undefined counteranion).
The cation appears in the head groups of phosphatidylcholine and sphingomyelin, two classes of phospholipid that are abundant in cell membranes. Choline is the precursor molecule for the neurotransmitter acetylcholine which is involved in many functions including memory and muscle control.
Choline must be consumed through the diet in order for the body to remain healthy. It is used in the synthesis of the constructional components in the body's cell membranes. Despite the perceived benefits of choline, dietary recommendations have discouraged people from eating certain high choline foods, such as egg and fatty meats. The 2005 National Health and Nutrition Examination Survey stated that only 2% of postmenopausal women consume the recommended intake for choline.
Choline was discovered by Adolph Strecker in 1864 and chemically synthesized in 1866. In 1998 choline was classified as an essential nutrient by the Food and
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. A psychoactive drug and one of the oldest recreational drugs known to man, ethanol produces a state known as alcohol intoxication when consumed. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a solvent, and as a fuel. In common usage, it is often referred to simply as alcohol or spirits.
Ethanol is a 2-carbon alcohol with the molecular formula CH3CH2OH. Its empirical formula is C2H6O. An alternative notation is CH3–CH2–OH, which indicates that the carbon of a methyl group (CH3–) is attached to the carbon of a methylene group (–CH2–), which is attached to the oxygen of a hydroxyl group (–OH). It is a constitutional isomer of dimethyl ether. Ethanol is often abbreviated as EtOH, using the common organic chemistry notation of representing the ethyl group (C2H5) with Et.
Ethanol is the systematic name defined by the IUPAC nomenclature of organic chemistry for a molecule with two carbon atoms (prefix "eth-"), having a single bond between them (suffix "-ane"), and an attached -OH group (suffix "-ol").
Sucrose is the organic compound commonly known as table sugar and sometimes called saccharose. A white, odorless, crystalline powder with a sweet taste, it is best known for its nutritional role. The molecule is a disaccharide composed of the monosaccharides glucose and fructose with the molecular formula C12H22O11. The word was formed in mid-19th century from Latin sucrum = "sugar" and the chemical suffix -ose.
The world produced about 168 million tonnes of table sugar in 2011.
Sucrose is a molecule with five stereocenters and many sites that are reactive or can be reactive. The molecule exists as a single isomer.
In sucrose, the components glucose and fructose are linked via an ether bond between C1 on the glucosyl subunit and C2 on the fructosyl unit. The bond is called a glycosidic linkage. Glucose exists predominantly as two isomeric "pyranoses" (α and β), but only one of these forms the links to the fructose. Fructose itself exists as a mixture of "furanoses", each of which having α and β isomers, but only one particular isomer links to the glucosyl unit. What is notable about sucrose is that, unlike most disaccharides, the glycosidic bond is formed between the reducing ends
Theobromine (theobromide), also known as xantheose, is a bitter alkaloid of the cacao plant, with the chemical formula C7H8N4O2. It is found in chocolate, as well as in a number of other foods, including the leaves of the tea plant, and the kola (or cola) nut. It is in the methylxanthine class of chemical compounds, which also includes the similar compounds theophylline and caffeine. (In caffeine, the only difference is that the NH group of theobromine is an N-CH3 group.) Despite its name, the compound contains no bromine—theobromine is derived from Theobroma, the name of the genus of the cacao tree, (which itself is made up of the Greek roots theo ("God") and brosi ("food"), meaning "food of the gods") with the suffix -ine given to alkaloids and other basic nitrogen-containing compounds.
Theobromine is a slightly water-soluble (330 mg/L), crystalline, bitter powder; the colour has been listed as either white or colourless. It has a similar, but lesser, effect than caffeine in the human nervous system, making it a lesser homologue. Theobromine is an isomer of theophylline, as well as paraxanthine. Theobromine is categorized as a dimethyl xanthine.
Theobromine was first discovered
Trans fat is the common name for unsaturated fat with trans-isomer (E-isomer) fatty acid(s). Because the term refers to the configuration of a double carbon-carbon bond, trans fats are sometimes monounsaturated or polyunsaturated, but never saturated. Trans fats do exist in nature but also occur during the processing of polyunsaturated fatty acids in food production.
The consumption of trans fats increases the risk of coronary heart disease by raising levels of LDL cholesterol and lowering levels of "good" HDL cholesterol. There is an ongoing debate about a possible differentiation between trans fats of natural origin and trans fats of vegetable origin but so far no scientific consensus was found. Two Canadian studies, that received funding by the Alberta Livestock and Meat Agency and the Dairy Farmers of Canada, have shown that the natural trans fat vaccenic acid, found in beef and dairy products, may have an opposite health effect and could actually be beneficial compared to hydrogenated vegetable shortening, or a mixture of pork lard and soy fat, e.g. lowering total and LDL cholesterol and triglyceride levels. In lack of recognized evidence and scientific agreement, nutritional
Vitamin B6 is a water-soluble vitamin and is part of the vitamin B complex group. Several forms of the vitamin are known, but pyridoxal phosphate (PLP) is the active form and is a cofactor in many reactions of amino acid metabolism, including transamination, deamination, and decarboxylation. PLP also is necessary for the enzymatic reaction governing the release of glucose from glycogen.
Vitamin B6 is a water-soluble compound that was discovered in the 1930s during nutrition studies on rats. In 1934, a Hungarian physician, Paul György discovered a substance that was able to cure a skin disease in rats (dermititis acrodynia), this substance he named vitamin B6. In 1938, Samuel Lepkovsky isolated vitamin B6 from rice bran. Harris and Folkers in 1939 determined the structure of pyridoxine, and, in 1945, Snell was able to show the two forms of vitamin B6, pyridoxal and pyridoxamine. Vitamin B6 was named pyridoxine to indicate its structural homology to pyridine. All three forms of vitamin B6 are precursors of an activated compound known as pyridoxal 5'-phosphate (PLP), which plays a vital role as the cofactor of a large number of essential enzymes in the human body.
Enzymes dependent on
Cryptoxanthin is a natural carotenoid pigment. It has been isolated from a variety of sources including the petals and flowers of plants in the genus Physalis, orange rind, papaya, egg yolk, butter, apples, and bovine blood serum.
In terms of structure, cryptoxanthin is closely related to β-carotene, with only the addition of a hydroxyl group. It is a member of the class of carotenoids known as xanthophylls.
In a pure form, cryptoxanthin is a red crystalline solid with a metallic luster. It is freely soluble in chloroform, benzene, pyridine, and carbon disulfide.
In the human body, cryptoxanthin is converted to vitamin A (retinol) and is, therefore, considered a provitamin A. As with other carotenoids, cryptoxanthin is an antioxidant and may help prevent free radical damage to cells and DNA, as well as stimulate the repair of oxidative damage to DNA.
Recent findings of an inverse association between β-cryptoxanthin and lung cancer risk in several observational epidemiological studies suggest that β-cryptoxanthin could potentially act as a chemopreventive agent against lung cancer. On the other hand, in the Grade IV histology group of adult patients diagnosed with malignant glioma,
Starch or amylum is a carbohydrate consisting of a large number of glucose units joined by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store. It is the most common carbohydrate in the human diet and is contained in large amounts in such staple foods as potatoes, wheat, maize (corn), rice, and cassava.
Pure starch is a white, tasteless and odorless powder that is insoluble in cold water or alcohol. It consists of two types of molecules: the linear and helical amylose and the branched amylopectin. Depending on the plant, starch generally contains 20 to 25% amylose and 75 to 80% amylopectin by weight. Glycogen, the glucose store of animals, is a more branched version of amylopectin.
Starch is processed to produce many of the sugars in processed foods. Dissolving starch in warm water gives wheatpaste, which can be used as a thickening, stiffening or gluing agent. The biggest industrial non-food use of starch is as adhesive in the papermaking process.
The word "starch" is derived from Middle English sterchen, meaning to stiffen. "amylum" is Latin for starch, from the Greek αμυλον, "amylon" which means "not ground at a mill". The root amyl is used
Heptadecanoic acid, or margaric acid, is a saturated fatty acid. Its molecular formula is CH3(CH2)15COOH. It occurs as a trace component of the fat and milkfat of ruminants, but it does not occur in any natural animal or vegetable fat at concentrations over half a percent. Salts and esters of heptadecanoic acid are called heptadecanoates.
Phytosterols, which encompass plant sterols and stanols, are steroid compounds similar to cholesterol which occur in plants and vary only in carbon side chains and/or presence or absence of a double bond. Stanols are saturated sterols, having no double bonds in the sterol ring structure. More than 200 sterols and related compounds have been identified. Free phytosterols extracted from oils are insoluble in water, relatively insoluble in oil, and soluble in alcohols.
Phytosterol-enriched foods and dietary supplements have been marketed for decades. Despite well documented cholesterol-lowering effect, no evidence of any beneficial effect on cardiovascular disease (CVD) or overall mortality exists, and a meta-analysis published in 2012 suggests no effect.
Nomenclature for steroid skeleton (on right)
The richest naturally occurring sources of phytosterols are vegetable oils and products made from them. Nuts, which are rich in phytosterols, are often eaten in smaller amounts, but can still significantly contribute to total phytosterol intake. Cereal products, vegetables, fruit and berries, which are not as rich in phytosterols, may also be significant sources of phytosterols due to
Lysine (abbreviated as Lys or K) is an α-amino acid with the chemical formula HO2CCH(NH2)(CH2)4NH2. It is an essential amino acid for humans. Lysine's codons are AAA and AAG.
Lysine is a base, as are arginine and histidine. The ε-amino group often participates in hydrogen bonding and as a general base in catalysis. (The ε-amino group, which is attached to the NH3 group, is the fifth carbon down from the α-carbon, which is attached to the carboxyl (C=OOH) group.)
Common posttranslational modifications include methylation of the ε-amino group, giving methyl-, dimethyl-, and trimethyllysine. The latter occurs in calmodulin. Other posttranslational modifications at lysine residues include acetylation and ubiquitination. Collagen contains hydroxylysine, which is derived from lysine by lysyl hydroxylase. O-Glycosylation of hydroxylysine residues in the endoplasmic reticulum or Golgi apparatus is used to mark certain proteins for secretion from the cell.
As an essential amino acid, lysine is not synthesized in animals, hence it must be ingested as lysine or lysine-containing proteins. In plants and bacteria, it is synthesized from aspartic acid (aspartate):
Enzymes involved in this
Phosphorus ( /ˈfɒsfərəs/ FOS-fər-əs) is a chemical element with symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidised state, as inorganic phosphate rocks. Elemental phosphorus exists in two major forms—white phosphorus and red phosphorus—but due to its high reactivity, phosphorus is never found as a free element on Earth.
The first form of elemental phosphorus to be produced (white phosphorus, in 1669) emits a faint glow upon exposure to oxygen – hence its name given from Greek mythology, Φωσφόρος meaning "light-bearer" (Latin Lucifer), referring to the "Morning Star", the planet Venus. The term "phosphorescence", meaning glow after illumination, originally derives from this property of phosphorus, although this word has since been used for a different physical process that produces a glow. The glow of phosphorus itself originates from oxidation of the white (but not red) phosphorus— a process now termed chemiluminescence.
The vast majority of phosphorus compounds are consumed as fertilisers. Other applications include the role of organophosphorus compounds in detergents, pesticides
Cholesterol, from the Greek chole- (bile) and stereos (solid) followed by the chemical suffix -ol for an alcohol, is an organic chemical substance classified as a waxy steroid of fat. It is an essential structural component of mammalian cell membranes and is required to establish proper membrane permeability and fluidity.
In addition to its importance within cells, cholesterol also serves as a precursor for the biosynthesis of steroid hormones, bile acids, and vitamin D. Cholesterol is the principal sterol synthesized by animals; in vertebrates it is formed predominantly in the liver. Small quantities are synthesized in other cellular organisms (eukaryotes) such as plants and fungi. It is almost completely absent among prokaryotes (i.e., bacteria).
Although cholesterol is important and necessary for human health, high levels of cholesterol in the blood have been linked to damage to arteries and cardiovascular disease.
François Poulletier de la Salle first identified cholesterol in solid form in gallstones, in 1769. However, it was only in 1815 that chemist Eugène Chevreul named the compound "cholesterine".
Since cholesterol is essential for all animal life, each cell synthesizes it
An unsaturated fatty acid that is the most widely distributed and abundant fatty acid in nature. It is used commercially in the preparation of oleates and lotions, and as a pharmaceutical solvent. (Stedman, 26th ed)
Tyrosine (abbreviated as Tyr or Y) or 4-hydroxyphenylalanine, is one of the 22 amino acids that are used by cells to synthesize proteins. Its codons are UAC and UAU. It is a non-essential amino acid with a polar side group. The word "tyrosine" is from the Greek tyri, meaning cheese, as it was first discovered in 1846 by German chemist Justus von Liebig in the protein casein from cheese. It is called tyrosyl when referred to as a functional group or side chain.
Aside from being a proteinogenic amino acid, tyrosine has a special role by virtue of the phenol functionality. It occurs in proteins that are part of signal transduction processes. It functions as a receiver of phosphate groups that are transferred by way of protein kinases (so-called receptor tyrosine kinases). Phosphorylation of the hydroxyl group changes the activity of the target protein.
A tyrosine residue also plays an important role in photosynthesis. In chloroplasts (photosystem II), it acts as an electron donor in the reduction of oxidized chlorophyll. In this process, it undergoes deprotonation of its phenolic OH-group. This radical is subsequently reduced in the photosystem II by the four core manganese clusters.
Magnesium ( /mæɡˈniːziəm/ mag-NEE-zee-əm) is a chemical element with symbol Mg and atomic number 12. Its common oxidation number is +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole. Magnesium is the fourth most common element in the Earth as a whole (behind iron, oxygen and silicon), making up 13% of the planet's mass and a large fraction of the planet's mantle. The relative abundance of magnesium is related to the fact that it is easily built up in supernova stars from a sequential addition of three helium nuclei to carbon (which in turn is made from three helium nuclei). Due to magnesium ion's high solubility in water, it is the third most abundant element dissolved in seawater.
The free element (metal) is not found naturally on Earth, as it is highly reactive (though once produced, it is coated in a thin layer of oxide (see passivation), which partly masks this reactivity). The free metal burns with a characteristic brilliant white light, making it a useful ingredient in flares. The metal is now mainly obtained by electrolysis of magnesium salts obtained from brine. Commercially, the chief use
Saturated fat is fat that consists of triglycerides containing only saturated fatty acids. Saturated fatty acids have no double bonds between the individual carbon atoms of the fatty acid chain. That is, the chain of carbon atoms is fully "saturated" with hydrogen atoms. There are many kinds of naturally occurring saturated fatty acids, which differ mainly in number of carbon atoms, from 3 carbons (propionic acid) to 36 (hexatriacontanoic acid).
Various fats contain different proportions of saturated and unsaturated fat. Examples of foods containing a high proportion of saturated fat include animal fats such as cream, cheese, butter, and ghee; suet, tallow, lard, and fatty meats; as well as certain vegetable products such as coconut oil, cottonseed oil, palm kernel oil, chocolate, and many prepared foods.
While nutrition labels regularly combine them, the saturated fatty acids appear in different proportions among food groups. Lauric and myristic acids are most commonly found in "tropical" oils (e.g., palm kernel, coconut) and dairy products. The saturated fat in meat, eggs, chocolate, and nuts is primarily the triglycerides of palmitic and stearic acids.
Some common examples of
Proteins ( /ˈproʊˌtiːnz/ or /ˈproʊti.ɨnz/) are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function.
A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of adjacent amino acid residues. The sequence of amino acids in a protein is defined by the sequence of a gene, which is encoded in the genetic code. In general, the genetic code specifies 20 standard amino acids; however, in certain organisms the genetic code can include selenocysteine and—in certain archaea—pyrrolysine. Shortly after or even during synthesis, the residues in a protein are often chemically modified by posttranslational modification, which alters the physical and chemical properties, folding, stability, activity, and ultimately, the function of the proteins. Sometimes proteins have non-peptide groups attached, which can be called prosthetic groups or cofactors. Proteins can also work together to achieve a particular function, and they often associate to form stable protein complexes.
Like other biological macromolecules such as polysaccharides
In analytical chemistry, ashing is the process of mineralization for preconcentration of trace substances prior to chemical analysis. Ash is the name given to all non-aqueous residue that remains after a sample is burned, which consists mostly of metal oxides. Ash content may be listed in nutrition labels, such as for pet food.
Ash is one of the components in the proximate analysis of biological materials, consisting mainly of salty, inorganic constituents. It includes metal salts which are important for processes requiring ions such as Na (Sodium), K (Potassium), Ca (Calcium). It also includes trace minerals which are required for unique molecules, such as chlorophyll and hemoglobin.
For instance, the analysis of honey shows:
In this example the ash would include all the minerals in honey.
Caprylic acid is the common name for the eight-carbon saturated fatty acid known by the systematic name octanoic acid. It is found naturally in the milk of various mammals, and it is a minor constituent of coconut oil and palm kernel oil. It is an oily liquid that is minimally soluble in water with a slightly unpleasant rancid-like smell and taste.
Two other acids are named after goats: caproic (C6) and capric (C10). Along with caprylic acid these total 15% in goat milk fat.
Caprylic acid is used commercially in the production of esters used in perfumery and also in the manufacture of dyes.
Caprylic acid is also used in the treatment of some bacterial infections. Due to its relatively short chain length it has no difficulty in penetrating fatty cell wall membranes, hence its effectiveness in combating certain lipid-coated bacteria, such as Staphylococcus aureus and various species of Streptococcus.
Caprylic acid is an antimicrobial pesticide used as a food contact surface sanitizer in commercial food handling establishments on dairy equipment, food processing equipment, breweries, wineries, and beverage processing plants. It is also used as disinfectant in health care facilities,
γ-Linolenic acid (gamma-linolenic acid or GLA, INN and USAN gamolenic acid) is a fatty acid found primarily in vegetable oils. It is sold as a dietary supplement for treating problems with inflammation and auto-immune diseases, although its efficacy is disputed.
GLA is categorized as an n−6 (also called ω−6 or omega-6) fatty acid, meaning that the first double bond on the methyl end (designated with n or ω) is the sixth bond. In physiological literature, GLA is designated as 18:3 (n−6). GLA is a carboxylic acid with an 18-carbon chain and three cis double bonds. It is an isomer of α-linolenic acid, which is a polyunsaturated n−3 (omega-3) fatty acid, found in rapeseed (canola), soybeans, walnuts, flaxseed (linseed oil), perilla, chia, and hempseed.
GLA was first isolated from the seed oil of evening primrose. This herbal plant was grown by Native Americans to treat swelling in the body. In the 17th century, it was introduced to Europe and became a popular folk remedy, earning the name king's cure-all. in 1919, Heiduschka and Lüft extracted the oil from evening primrose seeds and described an unusual linolenic acid, which they name γ-. Later, the exact chemical structure was
Caffeine is a bitter, white crystalline xanthine alkaloid that acts as a stimulant drug and an acetylcholinesterase inhibitor. Caffeine is found in varying quantities in the seeds, leaves, and fruit of some plants, where it acts as a natural pesticide that paralyzes and kills certain insects feeding on the plants. It is most commonly consumed by humans in infusions extracted from the seed of the coffee plant and the leaves of the tea bush, as well as from various foods and drinks containing products derived from the kola nut. Other sources include yerba maté, guarana berries, guayusa, and the yaupon holly.
In humans, caffeine acts as a central nervous system stimulant, temporarily warding off drowsiness and restoring alertness. It is the world's most widely consumed psychoactive drug, but, unlike many other psychoactive substances, it is both legal and unregulated in nearly all parts of the world. Beverages containing caffeine, such as coffee, tea, soft drinks, and energy drinks, enjoy great popularity; in North America, 90% of adults consume caffeine daily.
Caffeine is toxic at sufficiently high doses. Ordinary consumption can have low health risks, even when carried on for years
An unsaturated, essential fatty acid. It is found in animal and human fat as well as in the liver, brain, and glandular organs, and is a constituent of animal phosphatides. It is formed by the synthesis from dietary linoleic acid and is a precursor in the biosynthesis of prostaglandins, thromboxanes, and leukotrienes.
Hydroxyproline is an uncommon amino acid. Hydroxyproline differs from proline by the presence of a hydroxyl (OH) group attached to the C (gamma) atom. Hydroxyproline is produced by hydroxylation of the amino acid proline. It is not directly coded for by DNA, however, and is hydroxylated after protein synthesis. Hydroxyproline is a major component of the protein collagen. Hydroxyproline and proline play key roles for collagen stability. They permit the sharp twisting of the collagen helix. It helps provide stability to the triple-helical structure of collagen by forming hydrogen bonds. Hydroxyproline is found in few proteins other than collagen. The only other mammalian protein which includes hydroxyproline is elastin. For this reason, hydroxyproline content has been used as an indicator to determine collagen and/or gelatin amount. Proline hydroxylation requires ascorbic acid. The most obvious, first effects (gum and hair problems) of absence of ascorbic acid in humans come from the resulting defect in hydroxylation of proline residues of collagen, with reduced stability of the collagen molecule causing scurvy. (http://en.wikipedia.org/wiki/Hydroxyproline) Hydroxyproline levels increase in cases of psychotic depression. These patients also may require extra vitamin C. (http://www.dcnutrition.com/AminoAcids)
Polyunsaturated lipids are triacylglycerols in which the hydrocarbon tails (caudae) of this ester constitutes polyunsaturated fatty acid (PUFA) (fatty acids possessing more than a single carbon–carbon double bond). "Unsaturated" refers to the fact that the molecules contain less than the maximum amount of hydrogen. These materials exist as cis or trans isomers depending on the geometry of the double bond.
Saturated fats have hydrocarbon chains which can be most readily aligned. The hydrocarbon chains in trans fats align more readily than those in cis fats, but less well than those in saturated fats. This means that, in general, the melting points of fats increase from cis to trans unsaturated and then to saturated. See the section on chemical structure of fats for more information.
The position of the carbon-carbon double bonds in carboxylic acid chains in fats is designated by Greek letters. The carbon atom closest to the carboxyl group is the alpha carbon, the next carbon is the beta carbon and so on. In fatty acids the carbon atom of the methyl group at the end of the hydrocarbon chain is called the omega carbon because omega is the last letter of the Greek alphabet. Omega-3
Retinol is one of the animal forms of vitamin A. It is a diterpenoid and an alcohol. It is convertible to other forms of vitamin A, and the retinyl ester derivative of the alcohol serves as the storage form of the vitamin in animals.
When converted to the retinal (retinaldehyde) form, vitamin A is essential for vision, and when converted to retinoic acid, is essential for skin health, teeth remineralization and bone growth. These chemical compounds are collectively known as retinoids, and possess the structural motif of all-trans retinol as a common feature in their structure. Structurally, all retinoids also possess a β-ionone ring and a polyunsaturated side chain, with either an alcohol, aldehyde, a carboxylic acid group or an ester group. The side chain is composed of four isoprenoid units, with a series of conjugated double bonds which may exist in trans- or cis-configuration.
Retinol is produced in the body from the hydrolysis of retinyl esters, and from the reduction of retinal. Retinol in turn is ingested in a precursor form; animal sources (liver and eggs) contain retinyl esters, whereas plants (carrots, spinach) contain pro-vitamin A carotenoids (these may also be
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at temperatures above 0 °C (273.15 K, 32 °F) at sea level, but it often co-exists on Earth with its solid state, ice, and gaseous state (water vapor or steam). Water also exists in a liquid crystal state near hydrophilic surfaces.
Water covers 71% of the Earth's surface, and is vital for all known forms of life. On Earth, 96.5% of the planet's water is found in oceans, 1.7% in groundwater, 1.7% in glaciers and the ice caps of Antarctica and Greenland, a small fraction in other large water bodies, and 0.001% in the air as vapor, clouds (formed of solid and liquid water particles suspended in air), and precipitation. Only 2.5% of the Earth's water is freshwater, and 98.8% of that water is in ice and groundwater. Less than 0.3% of all freshwater is in rivers, lakes, and the atmosphere, and an even smaller amount of the Earth's freshwater (0.003%) is contained within biological bodies and manufactured products.
Water on Earth moves continually through the hydrological cycle of evaporation and transpiration
Iron (AE /ˈaɪərn/ EYE-ər-n, BE /ˈaɪən/ EYE-ən) is a chemical element with the symbol Fe (from Latin: ferrum) and atomic number 26. It is a metal in the first transition series. It is the most common element (by mass) forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. Iron's very common presence in rocky planets like Earth is due to its abundant production as a result of fusion in high-mass stars, where the production of nickel-56 (which decays to the most common isotope of iron) is the last nuclear fusion reaction that is exothermic. This causes radioactive nickel to become the last element to be produced before collapse of a supernova leads to the explosive events that scatter this precursor radionuclide of iron abundantly into space.
Like other group 8 elements, iron exists in a wide range of oxidation states, −2 to +6, although +2 and +3 are the most common. Elemental iron occurs in meteoroids and other low oxygen environments, but is reactive to oxygen and water. Fresh iron surfaces appear lustrous silvery-gray, but oxidize in normal air to give iron oxides, also known as rust. Unlike
Lipids constitute a broad group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, phospholipids, and others. The main biological functions of lipids include energy storage, as structural components of cell membranes, and as important signaling molecules.
Lipids may be broadly defined as hydrophobic or amphiphilic small molecules; the amphiphilic nature of some lipids allows them to form structures such as vesicles, liposomes, or membranes in an aqueous environment. Biological lipids originate entirely or in part from two distinct types of biochemical subunits or "building-blocks": ketoacyl and isoprene groups. Using this approach, lipids may be divided into eight categories: fatty acids, glycerolipids, glycerophospholipids, sphingolipids, saccharolipids, and polyketides (derived from condensation of ketoacyl subunits); and sterol lipids and prenol lipids (derived from condensation of isoprene subunits).
Although the term lipid is sometimes used as a synonym for fats, fats are a subgroup of lipids called triglycerides. Lipids also encompass molecules such as fatty
Phylloquinone is a polycyclic aromatic ketone, based on 2-methyl-1,4-naphthoquinone, with a 3-phytyl substituent.
It is a fat-soluble vitamin that is stable to air and moisture but decomposes in sunlight. It is found naturally in a wide variety of green plants, particularly leaves, since it functions as an electron acceptor during photosynthesis, forming part of the electron transport chain of Photosystem I.
It is often called vitamin K1, phytomenadione or phytonadione. Sometimes a distinction is made with phylloquinone considered natural and phytonadione considered synthetic.
A stereoisomer of phylloquinone is called vitamin k1 (note the difference in capitalization).
Phylloquinone is an electron acceptor during photosynthesis, forming part of the electron transport chain of Photosystem I.
Its best-known function in animals is as a cofactor in the formation of coagulation factors II (prothrombin), VII, IX, and X by the liver. It is also required for the formation of anticoagulant factors protein C and S. It is commonly used to treat warfarin toxicity, and as an antidote for coumatetralyl.
Vitamin K is also required for bone protein formation.
Proline (abbreviated as Pro or P) is an α-amino acid, one of the twenty DNA-encoded amino acids. Its codons are CCU, CCC, CCA, and CCG. It is not an essential amino acid, which means that the human body can synthesize it. It is unique among the 20 protein-forming amino acids in that the amine nitrogen is bound to not one but two alkyl groups, thus making it a secondary amine. The more common L form has S stereochemistry.
Proline is biosynthetically derived from the amino acid L-glutamate and its immediate precursor is the imino acid (S)-1-pyrroline-5-carboxylate (P5C). Enzymes involved in a typical biosynthesis include:
The distinctive cyclic structure of proline's side chain locks its φ backbone dihedral angle at approximately −60°, giving proline an exceptional conformational rigidity compared to other amino acids. Hence, proline loses less conformational entropy upon folding, which may account for its higher prevalence in the proteins of thermophilic organisms. Proline acts as a structural disruptor in the middle of regular secondary structure elements such as alpha helices and beta sheets; however, proline is commonly found as the first residue of an alpha helix and also in the
α-Carotene is a form of carotene with a β-ring at one end and an ε-ring at the other. It is the second most common form of carotene.
In US adults and Chinese adults the mean concentration of serum α-carotene was 4.71 µg/dL, including 4.22 µg/dL among men and 5.31 µg/dL among women (to convert to micromoles per liter, multiply by 0.01863).
Dietary intake affects blood levels of α-carotene which was associated with significantly lower risk of death, in one study.
The following vegetables are rich in alpha-carotene :
Arginine (abbreviated as Arg or R) is an α-amino acid. It was first isolated in 1886. The L-form is one of the 20 most common natural amino acids. At the level of molecular genetics, in the structure of the messenger ribonucleic acid mRNA, CGU, CGC, CGA, CGG, AGA, and AGG, are the triplets of nucleotide bases or codons that codify for arginine during protein synthesis. In mammals, arginine is classified as a semiessential or conditionally essential amino acid, depending on the developmental stage and health status of the individual. Preterm infants are unable to synthesize or create arginine internally, making the amino acid nutritionally essential for them. There are some conditions that put an increased demand on the body for the synthesis of L-arginine, including surgical or other trauma, sepsis and burns. Arginine was first isolated from a lupin seedling extract in 1886 by the Swiss chemist Ernst Schultze.
In general, most people do not need to take arginine supplements because the body usually produces enough.
The amino acid side-chain of arginine consists of a 3-carbon aliphatic straight chain, the distal end of which is capped by a complex guanidinium group.
With a pKa of
Sugar is the generalised name for a class of sweet-flavored substances used as food. They are carbohydrates and as this name implies, are composed of carbon, hydrogen and oxygen. There are various types of sugar derived from different sources. Simple sugars are called monosaccharides and include glucose, fructose and galactose. The table or granulated sugar most customarily used as food is sucrose, a disaccharide. Other disaccharides include maltose and lactose.
Sugars are found in the tissues of most plants but are only present in sufficient concentrations for efficient extraction in sugarcane and sugar beet. Sugarcane is a giant grass and has been cultivated in tropical climates in the Far East since ancient times. A great expansion in its production took place in the 18th century with the setting up of sugar plantations in the West Indies and Americas. This was the first time that sugar became available to the common people who had previously had to rely on honey to sweeten foods. Sugar beet is a root crop and is cultivated in cooler climates and became a major source of sugar in the 19th century when methods for extracting the sugar became available. Sugar production and trade
Decanoic acid, or capric acid, is a saturated fatty acid. Its formula is CH3(CH2)8COOH. Salts and esters of decanoic acid are called decanoates or "caprates". The term capric acid arises from the Latin "capric" which pertains to goats due to their olfactory similarities.
Capric acid occurs naturally in coconut oil (about 10%) and palm kernel oil (about 4%), otheriwse it is uncommon in typical seed oils. It is found in the milk of various mammals and to a lesser extent in other animal fats.
Two other acids are named after goats: caproic (a C6 fatty acid) and caprylic (a C8 fatty acid). Along with decanoic acid, these total 15% in goat milk fat.
Decanoic acid can be prepared from oxidation of primary alcohol decanol, by using chromium trioxide (CrO3) oxidant under acidic conditions.
Neutralization of decanoic acid or saponification of its esters, typically triglycerides, with sodium hydroxide will give sodium decanoate. This salt (CH3(CH2)8COONa) is a component of some types of soap.
Manufacturing of esters for artificial fruit flavors and perfumes. Also as an intermediate in chemical syntheses. It is used in organic synthesis and industrially in the manufacture of perfumes,
Fats consist of a wide group of compounds that are generally soluble in organic solvents and generally insoluble in water. Chemically, fats are triglycerides, triesters of glycerol and any of several fatty acids. Fats may be either solid or liquid at room temperature, depending on their structure and composition. Although the words "oils", "fats", and "lipids" are all used to refer to fats, "oils" is usually used to refer to fats that are liquids at normal room temperature, while "fats" is usually used to refer to fats that are solids at normal room temperature. "Lipids" is used to refer to both liquid and solid fats, along with other related substances, usually in a medical or biochemical context. The word "oil" is also used for any substance that does not mix with water and has a greasy feel, such as petroleum (or crude oil), heating oil, and essential oils, regardless of its chemical structure.
Fats form a category of lipid, distinguished from other lipids by their chemical structure and physical properties. This category of molecules is important for many forms of life, serving both structural and metabolic functions. They are an important part of the diet of most heterotrophs
Maltose (pronunciation: /ˈmɔːltoʊs/ or /ˈmɔːltoʊz/), also known as maltobiose or malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4)bond, formed from a condensation reaction. The isomer isomaltose has two glucose molecules linked through an α(1→6) bond. Maltose is the second member of an important biochemical series of glucose chains. Maltose is the disaccharide produced when amylase breaks down starch. It is found in germinating seeds such as barley as they break down their starch stores to use for food. It is also produced when glucose is caramelized.
The addition of another glucose unit yields maltotriose; further additions will produce dextrins (also called maltodextrins) and eventually starch (glucose polymer).
Maltose can be broken down into two glucose molecules by hydrolysis. In living organisms, the enzyme maltase can achieve this very rapidly. In the laboratory, heating with a strong acid for several minutes will produce the same result. Isomaltose is broken by isomaltase.
The production of maltose from germinating cereals, such as barley, is an important part of the brewing process. When barley is malted, it is brought into a condition
Palmitoleic acid, or (Z)-9-hexadecenoic acid, is an omega-7 monounsaturated fatty acid with the formula CH3(CH2)5CH=CH(CH2)7COOH that is a common constituent of the glycerides of human adipose tissue. It is present in all tissues, but generally found in higher concentrations in the liver. It is biosynthesized from palmitic acid by the action of the enzyme delta-9 desaturase. A beneficial fatty acid, it has been shown to increase insulin sensitivity by suppressing inflammation, as well as inhibit the destruction of insulin-secreting pancreatic beta cells.
Palmitoleic acid can be abbreviated as 16:1∆. Dietary sources of palmitoleic acid include a variety of animal oils, vegetable oils, and marine oils. Macadamia oil (Macadamia integrifolia) and sea buckthorn oil (Hippophae rhamnoides) are botanical sources with high concentrations, containing 17% and 40% of palmitoleic acid, respectively.
In an analysis of numerous fatty acids, palmitoleate was shown to possibly influence fatty liver deposition/production, insulin action, palmitate, and fatty acid synthase, leading to proposal of a new term, "lipokine" having hormone-like effects.
As one such effect may include improved insulin
Arachidic acid, also called eicosanoic acid, is the saturated fatty acid with a 20 carbon chain. It is as a minor constituent of peanut oil (1.1%–1.7%) and corn oil (3%). Its name derives from the Latin arachis — peanut. It can be formed by the hydrogenation of arachidonic acid.
Reduction of arachidic acid yields arachidyl alcohol.
Arachidic acid is used for the production of detergents, photographic materials and lubricants.
Copper ( /ˈkɒpər/ KOP-ər) is a chemical element with the symbol Cu (from Latin: cuprum) and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; a freshly exposed surface has a reddish-orange color. It is used as a conductor of heat and electricity, a building material, and a constituent of various metal alloys.
The metal and its alloys have been used for thousands of years. In the Roman era, copper was principally mined on Cyprus, hence the origin of the name of the metal as сyprium (metal of Cyprus), later shortened to сuprum. Its compounds are commonly encountered as copper(II) salts, which often impart blue or green colors to minerals such as turquoise and have been widely used historically as pigments. Architectural structures built with copper corrode to give green verdigris (or patina). Decorative art prominently features copper, both by itself and as part of pigments.
Copper(II) ions are water-soluble, where they function at low concentration as bacteriostatic substances, fungicides, and wood preservatives. In sufficient amounts, they are poisonous to higher organisms; at lower concentrations it is an
A betaine (BEET-uh-een, bē'tə-ēn', -ĭn) in chemistry is any neutral chemical compound with a positively charged cationic functional group such as a quaternary ammonium or phosphonium cation (generally: onium ions) which bears no hydrogen atom and with a negatively charged functional group such as a carboxylate group which may not be adjacent to the cationic site. A betaine thus may be a specific type of zwitterion. Historically the term was reserved for trimethylglycine only. It is used as a medicine as well.
The correct pronunciation of the compound reflects its origin and first isolation from sugar beets, and does not derive from the Greek letter beta (β). However, it is often mispronounced beta-INE or even BEE-tayn.
In biological systems, many naturally occurring betaines serve as organic osmolytes, substances synthesised or taken up from the environment by cells for protection against osmotic stress, drought, high salinity or high temperature. Intracellular accumulation of betaines, non-perturbing to enzyme function, protein structure and membrane integrity, permits water retention in cells, thus protecting from the effects of dehydration. It is also a methyl donor of
Cystine is a dimeric amino acid formed by the oxidation of two cysteine residues that covalently link to make a disulfide bond. This organosulfur compound has the formula (SCH2CH(NH2)CO2H)2. It is a white solid, and melts at 247–249 °C. It was discovered in 1810 by William Hyde Wollaston but was not recognized as being derived of proteins until it was isolated from the horn of a cow in 1899. Through formation of disulfide bonds within and between protein molecules, cystine is a significant determinant of the tertiary structure of most proteins. Disulfide bonding, along with hydrogen bonding and hydrophobic interactions is partially responsible for the formation of the gluten matrix in bread. Human hair contains approximately 5% cystine by mass.
The disulfide link is readily reduced to give the corresponding thiol cysteine. This reaction is typically effected with thiols such as mercaptoethanol or dithiothreitol.
For this reason, the nutritional benefits and sources of cystine are identical to those for the more-common cysteine. Disulfide bonds cleave more rapidly at higher temperatures.
Histidine (abbreviated as His or H) is an α-amino acid with an imidazole functional group. It is one of the 22 proteinogenic amino acids. Its codons are CAU and CAC. Histidine was first isolated by German physician Albrecht Kossel in 1896. Histidine is an essential amino acid in humans and other mammals. It was initially thought that it was only essential for infants, but longer-term studies established that it is also essential for adult humans.
The imidazole sidechain of histidine has a pKa of approximately 6.0, and, overall, the amino acid has a pKa of 6.5. This means that, at physiologically relevant pH values, relatively small shifts in pH will change its average charge. Below a pH of 6, the imidazole ring is mostly protonated as described by the Henderson–Hasselbalch equation. When protonated, the imidazole ring bears two NH bonds and has a positive charge. The positive charge is equally distributed between both nitrogens and can be represented with two equally important resonance structures.
The imidazole ring of histidine is aromatic at all pH values. It contains six pi electrons: four from two double bonds and two from a nitrogen lone pair. It can form pi stacking
Lignoceric acid, or tetracosanoic acid, is the saturated fatty acid with formula C23H47COOH. It is found in wood tar, various cerebrosides, and in small amounts in most natural fats. The fatty acids of peanut oil contain small amounts of lignoceric acid (1.1%–2.2%). This fatty acid is also a byproduct of lignin production.
Reduction of lignoceric acid yields lignoceryl alcohol.
Manganese ( /ˈmæŋɡəniːz/ MANG-gə-neez) is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature (often in combination with iron), and in many minerals. Manganese is a metal with important industrial metal alloy uses, particularly in stainless steels.
Historically, manganese is named for various black minerals (such as pyrolusite) from the same region of Magnesia in Greece which gave names to similar-sounding magnesium, Mg, and magnetite, an ore of the element iron, Fe. By the mid-18th century, Swedish chemist Carl Wilhelm Scheele had used pyrolusite to produce chlorine. Scheele and others were aware that pyrolusite (now known to be manganese dioxide) contained a new element, but they were not able to isolate it. Johan Gottlieb Gahn was the first to isolate an impure sample of manganese metal in 1774, by reducing the dioxide with carbon.
Manganese phosphating is used as a treatment for rust and corrosion prevention on steel. Depending on their oxidation state, manganese ions have various colors and are used industrially as pigments. The permanganates of alkali and alkaline earth metals are powerful oxidizers. Manganese
β-Sitosterol is one of several phytosterols (plant sterols) with chemical structures similar to that of cholesterol. Sitosterols are white, waxy powders with a characteristic odor. They are hydrophobic and soluble in alcohols.
It is widely distributed in the plant kingdom and found in Nigella sativa, pecans, Serenoa repens (saw palmetto), avocados, Cucurbita pepo (pumpkin seed), Pygeum africanum, cashew fruit, rice bran, wheat germ, corn oils, soybeans, sea-buckthorn, wolfberries, and Wrightia tinctoria.
Alone and in combination with similar phytosterols, β-sitosterol reduces blood levels of cholesterol, and is sometimes used in treating hypercholesterolemia. β-Sitosterol inhibits cholesterol absorption in the intestine. When the sterol is absorbed in the intestine, it is transported by lipoproteins and incorporated into the cellular membrane. Phytosterols and phytostanols both inhibit the uptake of dietary and biliary cholesterol, decreasing the levels of LDL and serum total cholesterol. Because the structure of β-sitosterol is very similar to that of cholesterol, β-sitosterol takes the place of dietary and biliary cholesterol in micelles produced in the intestinal lumen. This
Calcium ( /ˈkælsiəm/ KAL-see-əm) is the chemical element with symbol Ca and atomic number 20. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust. Calcium is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.
Calcium is essential for living organisms, in particular in cell physiology, where movement of the calcium ion Ca into and out of the cytoplasm functions as a signal for many cellular processes. As a major material used in mineralization of bone, teeth and shells, calcium is the most abundant metal by mass in many animals.
In chemical terms, calcium is reactive and soft for a metal (though harder than lead, it can be cut with a knife with difficulty). It is a silvery metallic element that must be extracted by electrolysis from a fused salt like calcium chloride. Once produced, it rapidly forms a gray-white oxide and nitride coating when exposed to air. In bulk form (typically as chips or "turnings"), the metal is somewhat difficult to ignite, more so even than magnesium chips; but, when lit, the metal burns in air with a brilliant
Threonine (abbreviated as Thr or T) is an α-amino acid with the chemical formula HO2CCH(NH2)CH(OH)CH3. Its codons are ACU, ACA, ACC, and ACG. This essential amino acid is classified as polar. Together with serine, threonine is one of two proteinogenic amino acids bearing an alcohol group (tyrosine is not an alcohol but a phenol, since its hydroxyl group is bonded directly to an aromatic ring, giving it different acid/base and oxidative properties). It is also one of two common amino acids that bear a chiral side chain, along with isoleucine.
The threonine residue is susceptible to numerous posttranslational modifications. The hydroxy side-chain can undergo O-linked glycosylation. In addition, threonine residues undergo phosphorylation through the action of a threonine kinase. In its phosphorylated form, it can be referred to as phosphothreonine.
Threonine was discovered as the last of the 20 common proteinogenic amino acids in the 1930s by William Cumming Rose.
Threonine is one of two amino acids out of the twenty with two chiral centers. Threonine can exist in four possible stereoisomers with the following configurations: (2S,3R), (2R,3S), (2S,3S) and (2R,3R). However, the name
α-Linolenic acid is an organic compound found in many common vegetable oils. In terms of its structure, it is named all-cis-9,12,15-octadecatrienoic acid. In physiological literature, it is given the name 18:3 (n−3).
α-Linolenic acid is a carboxylic acid with an 18-carbon chain and three cis double bonds. The first double bond is located at the third carbon from the methyl end of the fatty acid chain, known as the n end. Thus, α-linolenic acid is a polyunsaturated n−3 (omega-3) fatty acid. It is an isomer of gamma-linolenic acid, a polyunsaturated n−6 (omega-6) fatty acid.
Alpha-linolenic acid was first isolated by Rollett as cited in J. W. McCutcheon's synthesis in 1942, and referred to in Green and Hilditch's 1930's survey. It was first artificially synthesized in 1995 from C6 homologating agents. A Wittig reaction of the phosphonium salt of [(Z-Z)-nona-3,6-dien-1-yl]triphenylphosphonium bromide with methyl 9-oxononanoate, followed by saponification, completed the synthesis.
Seed oils are the richest sources of α-linolenic acid, notably those of rapeseed (canola), soybeans, walnuts, flaxseed (linseed oil), perilla, chia, and hemp. α-Linolenic acid is also obtained from the
Glucose (/ˈɡluːkoʊs/ or /-koʊz/; C6H12O6, also known as D-glucose, dextrose, or grape sugar) is a simple monosaccharide found in plants. It is one of the three dietary monosaccharides, along with fructose and galactose, that are absorbed directly into the bloodstream during digestion. An important carbohydrate in biology, cells use it as the primary source of energy and a metabolic intermediate. Glucose is one of the main products of photosynthesis and fuels for cellular respiration. Glucose exists in several different molecular structures, but all of these structures can be divided into two families of mirror-images (stereoisomers). Only one set of these isomers exists in nature, those derived from the "right-handed form" of glucose, denoted D-glucose. D-glucose is sometimes referred to as dextrose, although the use of this name is strongly discouraged. The term dextrose is derived from dextrorotatory glucose. This name is therefore confusing when applied to the enantiomer, which rotates light in the opposite direction. Starch and cellulose are polymers derived from the dehydration of D-glucose. The other stereoisomer, called L-glucose, is hardly ever found in nature.
Hexanoic acid (caproic acid), is the carboxylic acid derived from hexane with the general formula C5H11COOH. It is a colorless oily liquid with an odor that is fatty, cheesy, waxy, and like that of goats or other barnyard animals. It is a fatty acid found naturally in various animal fats and oils, and is one of the chemicals that give the decomposing fleshy seed coat of the ginkgo its characteristic unpleasant odor. The primary use of hexanoic acid is in the manufacture of its esters for artificial flavors, and in the manufacture of hexyl derivatives, such as hexylphenols.
The salts and esters of this acid are known as hexanoates or caproates.
Two other acids are named after goats: caprylic (C8) and capric (C10). Along with hexanoic acid, these total 15% in goat milk fat.
Caproic, caprylic, and capric acids (capric is a crystal- or wax-like substance, whereas the other two are mobile liquids) are not only used for the formation of esters, but also commonly used "neat" in: butter, milk, cream, strawberry, bread, beer, nut, and other flavors.
Butyric acid (from Greek βούτυρο, meaning "butter"), also known under the systematic name butanoic acid, is a carboxylic acid with the structural formula CH3CH2CH2-COOH. Salts and esters of butyric acid are known as butyrates or butanoates. Butyric acid is found in milk, especially goat, sheep and buffalo's milk, butter, Parmesan cheese, and as a product of anaerobic fermentation (including in the colon and as body odor). It has an unpleasant smell and acrid taste, with a sweetish aftertaste (similar to ether). It can be detected by mammals with good scent detection abilities (such as dogs) at 10 ppb, whereas humans can detect it in concentrations above 10 ppm.
Butyric acid was first observed (in impure form) in 1814 by the French chemist Michel Eugène Chevreul. By 1818, he had purified it sufficiently to characterize it. The name of butyric acid comes from the Latin word for butter, butyrum (or buturum), the substance in which butyric acid was first found.
Butyric acid is a fatty acid occurring in the form of esters in animal fats. The triglyceride of butyric acid makes up 3% to 4% of butter. When butter goes rancid, butyric acid is liberated from the glyceride by hydrolysis,
Phenylalanine (abbreviated as Phe or F) is an α-amino acid with the formula C6H5CH2CH(NH2)COOH. This essential amino acid is classified as nonpolar because of the hydrophobic nature of the benzyl side chain. L-Phenylalanine (LPA) is an electrically neutral amino acid, one of the twenty common amino acids used to biochemically form proteins, coded for by DNA. The codons for L-phenylalanine are UUU and UUC. Phenylalanine is a precursor for tyrosine, the monoamine signaling molecules dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline), and the skin pigment melanin.
Phenylalanine is found naturally in the breast milk of mammals. It is used in the manufacture of food and drink products and sold as a nutritional supplement for its reputed analgesic and antidepressant effects. It is a direct precursor to the neuromodulator phenylethylamine, a commonly used dietary supplement.
L-Phenylalanine is biologically converted into L-tyrosine, another one of the DNA-encoded amino acids. L-tyrosine in turn is converted into L-DOPA, which is further converted into dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline). The latter three are known as the
Galactose (from Greek γάλακτος galaktos "milk"), sometimes abbreviated Gal, is a type of sugar that is less sweet than glucose. It is a C-4 epimer of glucose.
Galactan is a polymer of the sugar galactose found in hemicellulose. Galactan can be converted to galactose by hydrolysis.
Galactose exists in both open-chain and cyclic form. The open-chain form has a carbonyl at the end of the chain.
Four isomers are cyclic, two of them with a pyranose (six-membered) ring, two with a furanose (five-membered) ring. Galactofuranose occurs in bacteria, fungi and protozoa.
Galactose is a monosaccharide. When combined with glucose (monosaccharide), through a dehydration reaction, the result is the disaccharide lactose. The hydrolysis of lactose to glucose and galactose is catalyzed by the enzymes lactase and β-galactosidase. The latter is produced by the lac operon in Escherichia coli.
Lactose is found primarily in milk and milk products. Galactose metabolism, which converts galactose into glucose, is carried out by the three principal enzymes in a mechanism known as the Leloir pathway. The enzymes are listed in the order of the metabolic pathway: galactokinase (GALK), galactose-1-phosphate
β-Carotene is a strongly-coloured red-orange pigment abundant in plants and fruits. It is an organic compound and chemically is classified as a hydrocarbon and specifically as a terpenoid (isoprenoid), reflecting its derivation from isoprene units. β-Carotene is biosynthesized from geranylgeranyl pyrophosphate. It is a member of the carotenes, which are tetraterpenes, synthesized biochemically from eight isoprene units and thus having 40 carbons. Among this general class of carotenes, β-carotene is distinguished by having beta-rings at both ends of the molecule. Absorption of β-carotene is enhanced if eaten with fats, as carotenes are fat soluble.
Carotene is the substance in carrots that colours them orange and is the most common form of carotene in plants. When used as a food colouring, it has the E number E160a. The structure was deduced by Karrer et al. in 1930. In nature, β-carotene is a precursor (inactive form) to vitamin A via the action of beta-carotene 15,15'-monooxygenase. Isolation of β-carotene from fruits abundant in carotenoids is commonly done using column chromatography. The separation of β-carotene from the mixture of other carotenoids is based on the polarity of
Docosahexaenoic acid (DHA) is an omega-3 fatty acid that is a primary structural component of the human brain cerebral cortex, sperm, testicles and retina. It can be synthesized from alpha-linolenic acid or obtained directly from maternal milk or fish oil. DHA's structure is a carboxylic acid(~oic acid) with a 22-carbon chain (docosa- is Greek for 22) and six (Greek "hexa") cis double bonds (-en~); the first double bond is located at the third carbon from the omega end. Its trivial name is cervonic acid, its systematic name is all-cis-docosa-4,7,10,13,16,19-hexa-enoic acid, and its shorthand name is 22:6(n-3) in the nomenclature of fatty acids.
Cold-water oceanic fish oils are rich in DHA. Most of the DHA in fish and multi-cellular organisms with access to cold-water oceanic foods originates from photosynthetic and heterotrophic microalgae, and becomes increasingly concentrated in organisms the further they are up the food chain. DHA is also commercially manufactured from microalgae; Crypthecodinium cohnii and another of the genus Schizochytrium. DHA manufactured using microalgae is vegetarian. Some animals with access to seafood make very little DHA through metabolism, but obtain
Potassium ( /pɵˈtæsiəm/ po-TAS-ee-əm) is a chemical element with symbol K (from Neo-Latin kalium) and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.
Because potassium and sodium are chemically very similar, it took a long time before their salts were differentiated. The existence of multiple elements in their salts was suspected from 1702, and this was proven in 1807 when potassium and sodium were individually isolated from different salts by electrolysis. Potassium in nature occurs only in ionic salts. As such, it is found dissolved in seawater (which is 0.04% potassium by weight), and is part of many minerals.
Most industrial chemical applications of potassium employ the relatively high solubility in water of potassium compounds, such as potassium soaps. Potassium metal has only a few special applications, being replaced in most chemical reactions with sodium metal.
Potassium ions are necessary for the function of all living cells. Potassium ion diffusion is a key mechanism in nerve transmission, and potassium
Valine (abbreviated as Val or V) is an α-amino acid with the chemical formula HO2CCH(NH2)CH(CH3)2. L-Valine is one of 20 proteinogenic amino acids. Its codons are GUU, GUC, GUA, and GUG. This essential amino acid is classified as nonpolar. Human dietary sources include cottage cheese, fish, poultry, peanuts, sesame seeds, and lentils.
Along with leucine and isoleucine, valine is a branched-chain amino acid. It is named after the plant valerian. In sickle-cell disease, valine substitutes for the hydrophilic amino acid glutamic acid in hemoglobin. Because valine is hydrophobic, the hemoglobin is prone to abnormal aggregation.
Valine is an essential amino acid, hence it must be ingested, usually as a component of proteins. It is synthesized in plants via several steps starting from pyruvic acid. The initial part of the pathway also leads to leucine. The intermediate α-ketoisovalerate undergoes reductive amination with glutamate. Enzymes involved in this biosynthesis include:
Racemic valine can be synthesized by bromination of isovaleric acid followed by amination of the α-bromo derivative
Dietary fiber, dietary fibre, or sometimes roughage or ruffage is the indigestible portion of plant foods having two main components:
Dietary fibers can act by changing the nature of the contents of the gastrointestinal tract and by changing how other nutrients and chemicals are absorbed. Some types of soluble fiber absorb water to become a gelatinous, viscous substance and is fermented by bacteria in the digestive tract. Some types of insoluble fiber have bulking action and is not fermented. Lignin, a major dietary insoluble fiber source, may alter the rate and metabolism of soluble fibers. Other types of insoluble fiber, notably resistant starch, are fully fermented.
Chemically, dietary fiber consists of non-starch polysaccharides such as arabinoxylans, cellulose, and many other plant components such as resistant starch, resistant dextrins, inulin, lignin, waxes, chitins, pectins, beta-glucans, and oligosaccharides. A novel position has been adopted by the US Department of Agriculture to include functional fibers as isolated fiber sources that may be included in the diet. The term "fiber" is something of a misnomer, since many types of so-called dietary fiber are not actually
Lauric acid, or dodecanoic acid is the main fatty acid in coconut oil and in palm kernel oil, and is believed to have antimicrobial properties. It is a white, powdery solid with a faint odor of bay oil. Lauric acid, although slightly irritating to mucous membranes, has a very low toxicity and so is used in many soaps and shampoos.
Erucic acid is a monounsaturated omega-9 fatty acid, denoted 22:1ω9. It has the formula CH3(CH2)7CH=CH(CH2)11COOH. It is prevalent in wallflower seed, makes up 4.1% of rapeseed oil, and makes up 42% of mustard oil. Erucic acid is also known as cis-13-docosenoic acid and the trans isomer is known as brassidic acid.
Erucic acid has many of the same uses as mineral oils, but it is more readily biodegradable than some. It has limited ability to polymerize and dry for use in oil paints. Like other fatty acids, it can be converted into surfactants, lubricant and is a precursor to bio-diesel.
Derivatives of erucic acid have many further uses, such as behenyl alcohol (CH3(CH2)21OH), a pour point depressant (enabling liquids to flow at a lower temperature), and silver behenate, for use in photography. It is also used as an ingredient in appetite suppressants.
The name erucic means: of or pertaining to eruca; which is a genus of flowering plants in the family Brassicaceae. It is also the Latin for coleworth, which today is better known as kale.
Erucic acid is produced naturally (together with other fatty acids) across a great range of green plants, but especially so in members of the
Lactose is a disaccharide sugar that is found most notably in milk and is formed from galactose and glucose. Lactose makes up around 2~8% of milk (by weight), although the amount varies among species and individuals. It is extracted from sweet or sour whey. The name comes from lac or lactis, the Latin word for milk, plus the -ose ending used to name sugars. It has a formula of C12H22O11.
Lactose was discovered in milk in 1619 by Fabriccio Bartoletti, and identified as a sugar in 1780 by Carl Wilhelm Scheele.
Lactose is a disaccharide derived from the condensation of galactose and glucose, which form a β-1→4 glycosidic linkage. Its systematic name is β-D-galactopyranosyl-(1→4)-D-glucose. The glucose can be in either the α-pyranose form or the β-pyranose form, whereas the galactose can only have the β-pyranose form: hence α-lactose and β-lactose refer to anomeric form of the glucopyranose ring alone.
Lactose is hydrolysed to glucose and galactose, isomerised in alkaline solution to lactulose, and catalytically hydrogenated to the corresponding polyhydric alcohol, lactitol.
Lactose crystals have a characteristic tomahawk shape that can be observed with a light microscope.
Vitamin D is a group of fat-soluble secosteroids. In humans, vitamin D is unique because it can be ingested as cholecalciferol (vitamin D3) or ergocalciferol (vitamin D2) and because the body can also synthesize it (from cholesterol) when sun exposure is adequate (hence its nickname, the "sunshine vitamin").
Although vitamin D is commonly called a vitamin, it is not actually an essential dietary vitamin in the strict sense, as it can be synthesized in adequate amounts by all mammals from sunlight. An organic chemical compound (or related set of compounds) is only scientifically called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from their diet. However, as with other compounds commonly called vitamins, vitamin D was discovered in an effort to find the dietary substance that was lacking in a disease, namely, rickets, the childhood form of osteomalacia. Additionally, like other compounds called vitamins, in the developed world vitamin D is added to staple foods, such as milk, to avoid disease due to deficiency.
Measures of serum levels reflect endogenous synthesis from exposure to sunlight as well as intake from the diet, and
Aspartic acid (abbreviated as Asp or D) is an α-amino acid with the chemical formula HOOCCH(NH2)CH2COOH. The carboxylate anion, salt, or ester of aspartic acid is known as aspartate. The L-isomer of aspartate is one of the 20 proteinogenic amino acids, i.e., the building blocks of proteins. Its codons are GAU and GAC.
Aspartic acid is, together with glutamic acid, classified as an acidic amino acid with a pKa of 3.9, however in a peptide the pKa is highly dependent on the local environment. A pKa as high as 14 is not at all uncommon. Aspartate is pervasive in biosynthesis. As with all amino acids, the presence of acid protons depends on the residue's local chemical environment and the pH of the solution.
Aspartic acid was first discovered in 1827 by Plisson, derived from asparagine, which had been isolated from asparagus juice in 1806, by boiling with a base.
The term "aspartic acid" refers to either of two forms or a mixture of two. Of these two forms, only one, "L-aspartic acid", is directly incorporated into proteins. The biological roles of its counterpart, "D-aspartic acid" are more limited. Where enzymatic synthesis will produce one or the other, most chemical syntheses will
Eicosapentaenoic acid (EPA or also icosapentaenoic acid) is an omega-3 fatty acid. In physiological literature, it is given the name 20:5(n-3). It also has the trivial name timnodonic acid. In chemical structure, EPA is a carboxylic acid with a 20-carbon chain and five cis double bonds; the first double bond is located at the third carbon from the omega end.
EPA is a polyunsaturated fatty acid (PUFA) that acts as a precursor for prostaglandin-3 (which inhibits platelet aggregation), thromboxane-3, and leukotriene-5 groups (all eicosanoids).
It is obtained in the human diet by eating oily fish or fish oil— e.g., cod liver, herring, mackerel, salmon, menhaden and sardine, and various types of edible seaweed. It is also found in human breast milk.
However, fish do not naturally produce EPA, but obtain it from the algae they consume. It is available to humans from some non-animal sources (e.g., commercially, from microalgae). Microalgae are being developed as a commercial source. EPA is not usually found in higher plants, but it has been reported in trace amounts in purslane.
The human body converts alpha-linolenic acid (ALA) to EPA. ALA is itself an essential fatty acid, an
Fluoride is the anion F, the reduced form of fluorine when as an ion and when bonded to another element. Inorganic fluorine containing compounds are called fluorides. Fluoride, like other halides, is a monovalent ion (−1 charge). Its compounds often have properties that are distinct relative to other halides. Structurally, and to some extent chemically, the fluoride ion resembles the hydroxide ion.
Solutions of inorganic fluorides in water contain F and bifluoride HF−
2. Few inorganic fluorides are soluble in water without undergoing significant hydrolysis. In terms of its reactivity, fluoride differs significantly from chloride and other halides, and is more strongly solvated due to its smaller radius/charge ratio. Its closest chemical relative is hydroxide. When relatively unsolvated, fluoride anions are called "naked". Naked fluoride is a very strong lewis base. The presence of fluoride and its compounds can be detected by F NMR spectroscopy.
Many fluoride minerals are known, but of paramount commercial importance are fluorite and fluorapatite.
Fluoride is usually found naturally in low concentration in drinking water and foods. The concentration in seawater averages 1.3 parts
Glycine is a simple, nonessential amino acid, although experimental animals show reduced growth on low-glycine diets. The average adult ingests 3 to 5 grams of glycine daily. Glycine is involved in the body's production of DNA, phospholipids and collagen, and in release of energy. Glycine levels are effectively measured in plasma in both normal patients and those with inborn errors of glycine metabolism. (http://www.dcnutrition.com/AminoAcids/) Nonketotic hyperglycinaemia (OMIM 606899) is an autosomal recessive condition caused by deficient enzyme activity of the glycine cleavage enzyme system (EC 18.104.22.168). The glycine cleavage enzyme system comprises four proteins: P-, T-, H- and L-proteins (EC 22.214.171.124, EC 126.96.36.199 and EC 188.8.131.52 for P-, T- and L-proteins). Mutations have been described in the GLDC (OMIM 238300), AMT (OMIM 238310), and GCSH (OMIM 238330) genes encoding the P-, T-, and H-proteins respectively. The glycine cleavage system catalyses the oxidative conversion of glycine into carbon dioxide and ammonia, with the remaining one-carbon unit transferred to folate as methylenetetrahydrofolate. It is the main catabolic pathway for glycine and it also contributes to one-carbon metabolism. Patients with a deficiency of this enzyme system have increased glycine in plasma, urine and cerebrospinal fluid (CSF) with an increased CSF:plasma glycine ratio. (PMID 16151895)
Methionine ( /mɛˈθaɪ.ɵniːn/ or /mɛˈθaɪ.ɵnɪn/; abbreviated as Met or M) is an α-amino acid with the chemical formula HO2CCH(NH2)CH2CH2SCH3. This essential amino acid is classified as nonpolar. This amino-acid is coded by the codon AUG, also known as the initiation codon, since it indicates mRNA's coding region where translation into protein begins.
Together with cysteine, methionine is one of two sulfur-containing proteinogenic amino acids. Its derivative S-adenosyl methionine (SAM) serves as a methyl donor. Methionine is an intermediate in the biosynthesis of cysteine, carnitine, taurine, lecithin, phosphatidylcholine, and other phospholipids. Improper conversion of methionine can lead to atherosclerosis.
This amino acid is also used by plants for synthesis of ethylene. The process is known as the Yang Cycle or the methionine cycle.
Methionine is one of only two amino acids encoded by a single codon (AUG) in the standard genetic code (tryptophan, encoded by UGG, is the other). The codon AUG is also the "Start" message for a ribosome that signals the initiation of protein translation from mRNA. As a consequence, methionine is incorporated into the N-terminal position of all proteins
In biochemistry and nutrition, monounsaturated fats or MUFA (MonoUnsaturated Fatty Acid) are fatty acids that have one double bond in the fatty acid chain and all of the remainder of the carbon atoms in the chain are single-bonded. By contrast, polyunsaturated fatty acids have more than one double bond.
Fatty acids are long-chained molecules having an alkyl group at one end and a carboxylic acid group at the other end. Fatty acid viscosity (thickness) and melting temperature increases with decreasing number of double bonds. Therefore, monounsaturated fatty acids have a higher melting point than polyunsaturated fatty acids (more double bonds) and a lower melting point than saturated fatty acids (no double bonds). Monounsaturated fatty acids are liquids at room temperature and semisolid or solid when refrigerated. And if are taken to vacuum, they are destroyed.
Common monounsaturated fatty acids are palmitoleic acid (16:1 n−7), cis-vaccenic acid (18:1 n−7) and oleic acid (18:1 n−9). Palmitoleic acid has 16 carbon atoms with the first double bond occurring 7 carbon atoms away from the methyl group (and 9 carbons from the carboxyl end). It can be lengthened to the 18-carbon
A saturated 14-carbon fatty acid occurring in most animal and vegetable fats, particularly butterfat and coconut, palm, and nutmeg oils. It is used to synthesize flavor and as an ingredient in soaps and cosmetics. (From Dorland, 28th ed) Myristic acid is also commonly added to a penultimate nitrogen terminus glycine in receptor-associated kinases to confer the membrane localisation of the enzyme. this is achieved by the myristic acid having a high enough hydrophobicity to become incorporated into the fatty acyl core of the phospholipid bilayer of the plasma membrane of the eukaryotic cell.(wikipedia)
Nervonic acid is a monounsaturated omega-9 fatty acid. Nervonic acid has been identified as important in the biosynthesis of nerve cell myelin. It is found in the sphingolipids of white matter in human brain.
Nervonic acid is used in the treatment of disorders involving demyelination, such as adrenoleukodystrophy and multiple sclerosis where there is a decreased level of nervonic acid in sphingolipids.
Tryptophan (IUPAC-IUBMB abbreviation: Trp or W; IUPAC abbreviation: L-Trp or D-Trp; sold for medical use as Tryptan) is one of the 22 standard amino acids, as well as an essential amino acid in the human diet. It is encoded in the standard genetic code as the codon UGG. Only the L-stereoisomer of tryptophan is used in structural or enzyme proteins, but the D-stereoisomer is occasionally found in naturally produced peptides (for example, the marine venom peptide contryphan). The distinguishing structural characteristic of tryptophan is that it contains an indole functional group. It is an essential amino acid as demonstrated by its growth effects on rats.
The isolation of tryptophan was first reported by Frederick Hopkins in 1901 through hydrolysis of casein. From 600 grams of crude casein one obtains 4-8 grams of tryptophan.
Plants and microorganisms commonly synthesize tryptophan from shikimic acid or anthranilate. The latter condenses with phosphoribosylpyrophosphate (PRPP), generating pyrophosphate as a bi-product. After ring opening of the ribose moiety and following reductive decarboxylation, indole-3-glycerinephosphate is produced, which in turn is transformed into indole. In
Vitamin B12, vitamin B12 or vitamin B-12, also called cobalamin, is a water-soluble vitamin with a key role in the normal functioning of the brain and nervous system, and for the formation of blood. It is one of the eight B vitamins. It is normally involved in the metabolism of every cell of the human body, especially affecting DNA synthesis and regulation, but also fatty acid synthesis and energy production. Neither fungi, plants or animals are capable of producing vitamin B12. Only bacteria and archaea have the enzymes required for its synthesis, and they therefore form its only sources in nature. The vitamin is the largest and most structurally complicated vitamin and can be produced industrially only through bacterial fermentation-synthesis.
Vitamin B12 consists of a class of chemically related compounds (vitamers), all of which have vitamin activity. It contains the biochemically rare element cobalt. Biosynthesis of the basic structure of the vitamin is accomplished only by bacteria (which usually produce hydroxocobalamin), but conversion between different forms of the vitamin can be accomplished in the human body. A common semi-synthetic form of the vitamin, cyanocobalamin,
Vitamin C or L-ascorbic acid, or simply ascorbate (the anion of ascorbic acid), is an essential nutrient for humans and certain other animal species. Vitamin C refers to a number of vitamers that have vitamin C activity in animals, including ascorbic acid and its salts, and some oxidized forms of the molecule like dehydroascorbic acid. Ascorbate and ascorbic acid are both naturally present in the body when either of these is introduced into cells, since the forms interconvert according to pH.
Vitamin C is a cofactor in at least eight enzymatic reactions including several collagen synthesis reactions that, when dysfunctional, cause the most severe symptoms of scurvy. In animals, these reactions are especially important in wound-healing and in preventing bleeding from capillaries. Ascorbate may also act as an antioxidant against oxidative stress. However, the fact that the enantiomer D-ascorbate (not found in nature) has identical antioxidant acivity to L-ascorbate, yet far less vitamin activity, underscores the fact that most of the function of L-ascorbate as a vitamin relies not on its antioxidant properties, but upon enzymic reactions that are stereospecific. "Ascorbate" without
α-Parinaric acid is a conjugated polyunsaturated fatty acid. Discovered by Tsujimoto and Koyanagi in 1933, it contains 18 carbon atoms and 4 conjugated double bonds. The repeating single bond-double bond structure of α-parinaric acid distinguishes it structurally and chemically from the usual "methylene-interrupted" arrangement of polyunsaturated fatty acids that have double-bonds and single bonds separated by a methylene unit (CH2). Because of the fluorescent properties conferred by the alternating double bonds, α-parinaric acid is commonly used as a molecular probe in the study of biomembranes.
α-Parinaric acid occurs naturally in the seeds of the makita tree (Parinarium laurinum), a tree found in Fiji and other Pacific islands. Makita seeds contain about 46% α-parinaric acid, 34% α-eleostearic acid as major components, with lesser amounts of saturated fatty acids, oleic acid and linoleic acid. α-Parinaric acid is also found in the seed oil of Impatiens balsamina, a member of the family Balsaminaceae. The major fatty acids of Impatiens balsamina are 4.7% palmitic acid, 5.8% stearic acid, 2.8% arachidic acid, 18.3% oleic acid, 9.2% linoleic acid, 30.1% linolenic acid and 29.1%