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Vitamin B2 - Riboflavin

Author: akil, Posted on Monday, September 06 @ 09:04:56 IST by RxPG  

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German and Swiss scientists simultaneously made the first serious attempts to isolate a known fluorescent substance in the early 1930's. This yellow enzyme was later identified as "flavin mononucleotide" (FMN) or "riboflavin phosphate." In 1935, it was synthesized and later given its name. Since it was found to have a pentose side chain ribitol, which is similar to the sugar ribose, the name of "riboflavin" seemed the logical choice. This name was formally adopted by the Commission on Biochemical Nomenclature in 1952.

Once known as Vitamin G, this nutrient was later called "riboflavine" because its ribose unit conjugated to a protein in addition to having the yellowish-green fluorescent pigment called flavin (it is this pigment that causes the urine to turn yellow). The final "e" was later dropped upon learning that it really was not an amine.

Riboflavin is the parent of two enzyme helpers (coenzymes), known as FAD (flavin adenine dinucleotide) and FMN (flavin mononucleotide). They are involved in the activation of B6 and in the conversion of folacin (folic acid) to its coenzymes. Riboflavin is one of the few vitamins not destroyed by heat, oxidation, or acid, but it does dissolve in cooking water and is destroyed by light, especially ultraviolet. Under normal circumstances, it is easily absorbed in the body.

The function of riboflavin is in oxidation/reduction reactions, that is, reactions that involve combining with oxygen or the removing of hydrogen. Working with thiamin, niacin, and panthothenic acid, it oxidizes fat and carbohydrates to carbon dioxide in order to produce energy. This occurs in the Kreb's cycle, which is the major energy pathway of most tissues in the body. Along with helping to produce energy, riboflavin participates in the body's defence system to oxidize toxins and foreign substances so they can be removed from the body. It also assists the enzyme glutathione reductase which replenishes the antioxidant glutathione in the eye, among other places. Studies in China have demonstrated the protective effects of riboflavin and niacin in preventing a common type of cataract. Riboflavin is also vital in the production of steroid hormones by the adrenal glands and is essential for successful reproduction.

Since 1941, riboflavin has commonly been used as a "fortified" vitamin, but levels vary greatly from product to product. As mentioned, riboflavin is destroyed by light. Therefore, storing milk in see-through containers contributes to 75% of its loss in just three and one-half hours. Up to 20% can be lost just in the pasteurization or evaporation process, while 40% vanishes during the blanching of vegetables before canning or freezing. Unfortunately, raw fruits and vegetable provide very little riboflavin. Since the body's need for riboflavin directly corresponds to the number of calories consumed, a vegan's need is not as great as that of a meat-eater.

Those at risk for B complex deficiency in general, and riboflavin in particular, are those on severely restricted diets, alcoholics, the elderly, chronic users of fiber-based laxatives, as well as those who use tranquilizers, or who suffer from hypothroidism. Stress also increases the need for riboflavin.

A deficiency of riboflavin does not cause a distinctive human disease, except for ariboflavinosis. Officially classified as a riboflavin deficiency, it develops in conjuction with other B vitamin deficiencies occuring at the same time. Such symptoms as cheilosis (scaling around the corners of the mouth), found in a B6 deficiency, is also associated with a riboflavin deficiency. Another one is corneal vascularization, which is the formation of fine capillary blood vessels around the cornea, also seen during any inflammation or irritating condition affecting the cornea. This is just one good reason to obtain an overall picture of symptoms rather than just relying on one or a few to determine treatment.

Boric acid or borate, found in eye products, mouth washes, and even supplements, binds riboflavin, rendering it unusable to the body. Other drugs and medications can also bind riboflavin, such particularly medications as antibiotics, chlorpromazine, imipramine (Tofranil), amitriptyline (Elavil), antimalarials (chloroquine and quinacrine), doxorubicin (an anticancer drug), tranquillizers (especially phenothiazines), and sulfa drugs. In addition, chronic use of such soluble fibers as psyllium can also produce a riboflavin/Bvitamin deficiency.

Summary:
Other names include: Vitamin B2, Vitamin G, lyochrome, lactoflavin, hepatoflavin, ovoflavin, uroflavin, Beflavine, Flavaxin, Ribipea.
Its forms are: riboflavin and riboflavin phosphate.
Inhibitors are: light, alkali, water, drugs listed above, estrogen, alcohol, and fats.
Helpers are: Vitamins B3, B6, C, phosphorus, fiber.
Deficiency symptoms include: retarded growth, cracks and sores around the mouth, scaling of facial SKIN, frequent itching/burning/bloodshot eyes, light sensitivity, grainy feeling under the eyelids, eye fatigue, dilated eyes, sties, needing a higher volume of light to see, burning hands or feet, vaginal itching, genital rashes, eczema of the face and genitalia, inability to urinate, anemia, decreased appetite and weight, deterioration of digestion, fatigue, depression, increased emotional agitation, dizziness, trembling, decreased antibody production, delayed wound healing, thinning of hair, oily SKIN, SKIN inflammations, baldness, sore and purplish tongue (glossitis), and the deterioration of protein utilization.

Toxicity symptoms include: itching/numbness/burning or unusual SKIN sensations.

Vitamin B2 phosphate is a special form of Vitamin B2. Other names include: riboflavin phosphate, flavine mononucleotide, cytoflav, coflavinase, alloxazine mononucleotide.




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