B Vitamins

Thiamine, or thiamin, sometimes called aneurin, is a water-soluble vitamin of the B complex (vitamin B1), whose phosphate derivatives are involved in many cellular processes. The best characterized form is thiamine diphosphate (ThDP), a coenzyme in the catabolism of sugars and amino acids. In yeast, ThDP is also required in the first step of alcoholic fermentation.

Thiamine is synthesized in bacteria, fungi and plants. Animals must cover all their needs from their food and insufficient intake results in a disease called beriberi affecting the peripheral nervous system (polyneuritis) and/or the cardiovascular system, with fatal outcome if not cured by thiamine administration.Mahan LK, Escott-Stump S, editors. Krause's food, nutrition, & diet therapy. 10th ed. Philadelphia: W.B. Saunders Company; 2000 In less severe deficiency, nonspecific signs include malaise, weight loss, irritability and confusion.Combs, G. F. Jr. The vitamins: Fundamental Aspects in Nutrition and Health''. 3rd Edition. Ithaca, NY: Elsevier Academic Press; 2008 Today, there is still a lot of work devoted to elucidating the exact mechanisms by which thiamine deficiency leads to the specific symptoms observed (see below). Finally, new thiamine phosphate derivatives have recently been discovered, emphasizing the complexity of thiamine metabolism and the need for more research in the field.

Riboflavin (E101), also known as vitamin B2, is an easily absorbed 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. Like the other B vitamins, it plays a key role in energy metabolism, and is required for the metabolism of fats, ketone bodies, carbohydrates, and proteins.

Milk, cheese, leafy green vegetables, liver, kidneys, legumes such as mature soybeans, yeast, mushrooms and almonds are good sources of vitamin B2, but exposure to light destroys riboflavin.

The name "riboflavin" comes from "ribose" and "flavin".

Niacin, also known as vitamin B3 or nicotinic acid, is a water-soluble vitamin that prevents the deficiency disease pellagra. It is an organic compound with the molecular formula C6H5NO2. It 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. The terms niacin, nicotinamide, and vitamin B3 are often used interchangeably to refer to any one of this family of molecules, since they have a common biochemical activity.

Niacin is converted to nicotinamide and then to NAD and NADP in vivo. Although the two are identical in their vitamin activity, nicotinamide does not have the same pharmacological effects as niacin, which occur as side-effects of niacin's conversion. Thus nicotinamide does not reduce cholesterol or cause flushing, although nicotinamide may be toxic to the liver at doses exceeding 3 g/day for adults. Niacin is a precursor to NADH, NAD, NAD+, NADP and NADPH, which play essential metabolic roles in living cells. Niacin is involved in both DNA repair, and the production of steroid hormones in the adrenal gland.

Niacin is one of five vitamins associated with a pandemic deficiency disease: these are niacin (pellagra), vitamin C (scurvy), thiamin (beriberi), vitamin D (rickets), and vitamin A deficiency, a syndrome which has no common name but is one of the most common symptomatic deficiencies worldwide.

Pantothenic acid, also called vitamin B5 (a B vitamin), is a water-soluble vitamin required to sustain life (essential nutrient). Pantothenic acid is needed to form coenzyme-A (CoA), and is critical in the metabolism and synthesis of carbohydrates, proteins, and fats. In chemical structure, it is the amide between D-pantoate and beta-alanine. Its name is derived from the Greek pantothen () 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, and royal jelly. It is commonly found as its alcohol analog, the provitamin panthenol, and as calcium pantothenate.

Vitamin B6 is a water-soluble vitamin and is part of the vitamin B complex group. 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.

Biotin, also known as vitamin H or B7, is a water-soluble B-complex vitamin which is composed of an ureido (tetrahydroimidizalone) ring fused with a tetrahydrothiophene ring. A valeric acid substituent is attached to one of the carbon atoms of the tetrahydrothiophene ring. Biotin is a cofactor in the metabolism of fatty acids and leucine, and it plays a role in gluconeogenesis.

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| Name = Folic acid

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| ImageName = Folic acid

| IUPACName = (2S)-2-(2-amino-4-hydroxypteridin-6-yl)methylamino}phenyl)formamidopentanedioic acid

| OtherNames = N-​(4-​{(2-​amino-​4-​oxo-​1,​4-​dihydropteridin-​6-​yl)​methyl​amino}​benzoyl)-​L-​glutamic acid; pteroyl-L-glutamic acid; Vitamin B9; Vitamin M; Folacin

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Folic acid (also known as Vitamin B9 or Folacin) and Folate (the naturally occurring form) are forms of the water-soluble Vitamin B9. Vitamin B9 (Folic acid and Folate inclusive) is essential to numerous bodily functions ranging from nucleotide synthesis to the remethylation of homocysteine. It is especially important during periods of rapid cell division and growth. Both children and adults require folic acid to produce healthy red blood cells and prevent anemia.Dietary Supplement Fact Sheet: Folate. Office of Dietary Supplements, National Institutes of Health. http://ods.od.nih.gov/factsheets/folate.asp Folate and Folic acid derive their names from the Latin word folium (leaf).

Vitamin B12 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 body, especially affecting DNA synthesis and regulation, but also fatty acid synthesis and energy production.

Vitamin B12 is the name for a class of chemically-related compounds, all of which have vitamin activity. It is structurally the most complicated vitamin and it contains the biochemically rare element cobalt. Biosynthesis of the basic structure of the vitamin can only be accomplished by bacteria, but conversion between different forms of the vitamin can be accomplished in the human body. A common synthetic form of the vitamin, cyanocobalamin, does not occur in nature, but is used in many pharmaceuticals, supplements and as food additive, due to its stability and lower cost. In the body it is converted to the physiological forms, methylcobalamin and adenosylcobalamin, leaving behind the cyanide, albeit in minimal concentration. More recently, hydroxocobalamin, methylcobalamin and, adenosylcobalamin can also be found in more expensive pharmacological products and food supplements. The utility of these is presently debated.

Historically, vitamin B12 was discovered from its relationship to the disease pernicious anemia, which is an autoimmune disease that destroys parietal cells in the stomach that secrete intrinsic factor. Intrinsic factor is crucial for the normal absorption of B12, therefore, a lack of intrinsic factor, as seen in pernicious anemia, causes a vitamin B12 deficiency. Many other subtler kinds of vitamin B12 deficiency, and their biochemical effects, have since been elucidated.

Adenine is a nucleobase (a purine derivative) with a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate (ATP) and the cofactors nicotinamide adenine dinucleotide (NAD) and flavin adenine dinucleotide (FAD), and protein synthesis, as a chemical component of DNA and RNA.Definition of Adenine from the Genetics Home Reference - National Institutes of Health The shape of adenine is complementary to either thymine in DNA or uracil in RNA.

The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. Historically, the B vitamins were once thought to be a single vitamin, referred to as vitamin B (much as people refer to vitamin C or vitamin D). Later research showed that they are chemically distinct vitamins that often coexist in the same foods. Supplements containing all eight are generally referred to as a vitamin B complex. Individual B vitamin supplements are referred to by the specific name of each vitamin (e.g. B1, B2, B3 etc ).

4-Aminobenzoic acid (also known as '''para-aminobenzoic acid or PABA''') is an organic compound with the molecular formula C7H7NO2. PABA is a white crystalline substance that is only slightly soluble in water. It consists of a benzene ring substituted with an amino group and a carboxyl group.

Orotic acid is a heterocyclic compound and an acid; it is also known as pyrimidinecarboxylic acid. Historically, it was believed to be part of the vitamin B complex and was called vitamin B13, but it is now known that it is not a vitamin, but is instead manufactured in the body by intestinal flora.

Its salts, known as orotates, are sometimes used as mineral carriers in some dietary supplements, to increase their bioavailability. Lithium orotate is the most frequently used in this manner.

Pangamic acid is an ester derived from gluconic acid and dimethylglycine.Recent data on the structure of pangamic acid (vitamin B15). Telegdy Kovats, Laszlo; Berndorfer-Kraszner, Eva; Juhasz, Agnes; Gabor, Tamas. Acta Alimentaria Academiae Scientiarum Hungaricae (1976), 5(3), 281-8. It was first isolated by Ernst T. Krebs from apricot kernels,KREBS E T Sr; KREBS E T Jr; BEARD H H; MALIN R; HARRIS A T; BARTLETT C L Pangamic acid sodium: a newly isolated crystalline water-soluble factor; a preliminary report. International record of medicine and general practice clinics (1951), 164(1), 18-23. and has since been identified in some foods such as pulses.Singh, Jagdev; Handa, Mrs. Geeta; Nandi, L. N.; Manavalan, R.; Atal, C. K. D-Gluconodimethylaminoacetic acid from natural sources. Indian Drugs (1983), 20(5), 185-9. Also found in rice bran & apricot kernels.

Pangamic acid is also known as vitamin B15, but it is not widely accepted as a vitamin for it has not been shown to be essential in the human diet, and a deficiency in consumption of pangamic acid is not known to be associated with any disease."Vitamin B15 - Pangamic Acid", Elson M. Haas M.D.

The calcium salt of pangamic acid, calcium pangamate, is used as a mineral supplement. Like thiamine, pangamic acid causes a temporary drop in blood pressure lasting for about 20 minutes.

Dimethylglycine is a molecule created when trimethylglycine donates one of its methyl groups.

It is sometimes used as a treatment for autism, although the evidence for this at present is mostly anecdotal.

Amygdalin (from Greek: '' ?almond?), C20H27NO11, is a glycoside initially isolated from the seeds of the tree Prunus dulcis, also known as bitter almonds, by Pierre-Jean Robiquet

and A. F. Boutron-Charlard in 1803, and subsequently investigated by Liebig and Wöhler in 1830, and others. Several other related species in the genus of Prunus, including apricot (Prunus armeniaca) and black cherry (Prunus serotina''), also contain amygdalin. It was promoted as a cancer cure by Ernst T. Krebs under the name "Vitamin B17", but studies have found it to be ineffective.

Carnitine is a quaternary ammonium compound biosynthesized from the amino acids lysine and methionine. In living cells, it is required for the transport of fatty acids from the cytosol into the mitochondria during the breakdown of lipids (or fats) for the generation of metabolic energy. It is often sold as a nutritional supplement. Carnitine was originally found as a growth factor for mealworms and labeled vitamin Bt. Carnitine exists in two stereoisomers: its biologically active form is L-carnitine, while its enantiomer, D-carnitine, is biologically inactive.

Inositol or cyclohexane-1,2,3,4,5,6-hexol is a chemical compound with formula 6126 or (-CHOH-)6, a six-fold alcohol (polyol) of cyclohexane. It exists in nine possible stereoisomers, of which the most prominent form, widely occuring in nature, is '''cis-1,2,3,5-trans-4,6-cyclohexanehexol, or myo-inositol. Other naturally occurring isomers (though in minimal quantities) are scyllo-, chiro-, muco-, and neo-inositol. The other possible isomers are allo-, epi-, and cis-inositol'.

Myo-inositol plays an important role as the structural basis for a number of secondary messengers in eukaryotic cells, including inositol phosphates, phosphatidylinositol (PI) and phosphatidylinositol phosphate (PIP) lipids. It is found in many foods, in particular, in cereals with high bran content, nuts, beans, and fruit, especially cantaloupe melons and oranges. Inositol is not considered a vitamin itself because it can be synthesised by the body.

Myo''-Inositol was classified as a member of the vitamin B complex (often referred to as vitamin B8), but was found to be synthesized by the human body (thus, declassifying it as a vitamin). It should be noted, however, that substances such as niacin and choline can also be synthesized in the body, but are not made in amounts considered adequate for good health, and are classified as essential nutrients.

Choline is an organic compound, classified as a water-soluble essential nutrient

"Choline, PDRHealth"Choline" (An interview with Steven Zeisel, Editor-in-Chief of the Journal of Nutritional Biochemistry), Radio National Health Report with Norman Swan, Monday 17 April 2000"[http://www.nap.edu/openbook.php?record_id=6015&page=390]" Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (1998), Institute of Medicine. and usually grouped within the Vitamin B complex. This natural amine is found in the lipids that make up cell membranes and in the neurotransmitter acetylcholine. Adequate intakes (AI) for this micronutrient of between 425 to 550 milligrams daily, for adults, have been established by the Food and Nutrition Board of the Institute of Medicine of the National Academy of Sciences.

4-Aminobenzoic acid (also known as '''para-aminobenzoic acid or PABA''') is an organic compound with the molecular formula C7H7NO2. PABA is a white crystalline substance that is only slightly soluble in water. It consists of a benzene ring substituted with an amino group and a carboxyl group.