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Vitamin B2 (riboflavin)

Riboflavin, also known as vitamin B2, is a water-soluble vitamin that is manufactured by biosynthesis of various microorganisms and plants. Rriboflavin cannot be biosynthesized in vertebrate including humans. Because it is a precursor to coenzymes such as flavin adenine dinucleotide and flavin mononucleotide, that are required in the enzymatic oxidation of carbohydrates, riboflavin is essential to basic metabolism. In higher animals, insufficient riboflavin can cause loss of hair, inflammation of the skin, vision deterioration, and growth failure. Riboflavin is a precursor for flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN), coenzymes involved in the oxidation-reduction reactions of all cellular bodies, and thus is an essential nutrient for humans. Riboflavin-dependent enzymes include succinate dehydrogenase, NADH dehydrogenase, ferredoxin-NADP.sup.+ oxidoreductase, acyl-CoA dehydrogenase, and the pyruvate dehydrogenase complex. Consequently, fatty acid oxidation, the TCA cycle, mitochondrial electron-transport, photosynthesis, and numerous other cellular processes are critically dependent on either FMN or FAD as prosthetic groups. Vitamin B2 deficiency results in inflammation of the mucous membranes of the mouth and throat, cracks in the corners of the mouth, itching and inflammation in skin folds and similar skin damage, conjunctivitis, diminished visual acuity and clouding of the cornea. Therefore, riboflavin is used as a vitamin product for prevention or treatment of diseases associated with the aforementioned vitamin deficiency.

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