vitamins - part 2.pdf

WATER-SOLUBLE VITAMINS B-complex Vitamins Vitamin B1 Thiamine or vitamin B1 has substituted pyrimidine and thiazole rings linked by a methylene bridge. Final steps in both the biosynthesis and chemical synthesis of this vitamin involve linkage of the two ring systems. Commercial supplies of thiam...

WATER-SOLUBLE VITAMINS B-complex Vitamins Vitamin B1 Thiamine or vitamin B1 has substituted pyrimidine and thiazole rings linked by a methylene bridge. Final steps in both the biosynthesis and chemical synthesis of this vitamin involve linkage of the two ring systems. Commercial supplies of thiamine are prepared by chemical synthesis, and it is usually used as the hydrochloride salt. The vitamin is stable in an acidic environment but decomposes readily above pH 5.0. It is estimated that about 50% of the vitamin in foods is destroyed during cooking. Source: Whole grains, legumes, and meats are good dietary sources of thiamine. Although the substance is absorbed readily from the small intestine, alcohol inhibits its absorption. Uses of Vitamin B1 1.Thiamin is a sulfur-containing vitamin that participates in energy metabolism 2.converting carbohydrates, lipids and proteins into energy. 3. plays a key role in nerve and muscle activity. 4.Thiamin may be helpful to people with Alzheimer disease. 5.Development of myelin sheaths and improves brain function Vitamin B1 (thiamine) deficiency cause of several clinical syndromes, including Wernicke, encephalopathy, beriberi. Risk factors include alcohol dependence, malabsorption, and a diet low in thiamine (e.g., based on polished rice). Beri beri Vitamin B2 Riboflavin or vitamin B 2 is a yellow, heat-stable substance that is slightly soluble in water. It is sensitive to light and will change into lumichrome or lumiflavin, depending on whether the irradiated solution is acidic or alkaline; neither lumichrome nor lumiflavin possesses physiologic activity. Sources: Yeast is the richest natural source of riboflavin. Dairy products, eggs, legumes, and meats are the main dietary sources of this vitamin. Small amounts are provided by cereal grains, fruits, and green vegetables. Riboflavin is stable during cooking in the absence of light. Riboflavin occurs in foods in the free form and as riboflavin 5'- phosphate (Flavin mononucleotide or FMN) and flavin adenine dinucleotide (FAD). The nucleotides are hydrolyzed to riboflavin in the upper gastrointestinal tract. Free riboflavin is absorbed readily into cells of the intestinal mucosa by an active transport system that is enhanced by bile salt. Uses of Vitamin B2 1.Coenzyme functions in numerous oxidation-reduction reactions which are necessary for releasing energy from carbohydrates, fats and proteins. 2. stimulates growth and reproduction 3.plays a role in vision 4.plays a role in conversion of vitamins B6, folic acid, and niacin into their active coenzyme forms. 5.neutralizes free radicals hence acts as anti-oxidant Deficiency causes stomatitis and dermatitis vitamin B3 Niacin, nicotinic acid, or vitamin B3 is a simple, naturally occurring pyridine derivative that prevents pellagra. Niacinamide or nicotinamide also occurs naturally, has antipellagra activity, and is used for dietary and therapeutic purposes. They are readily absorbed from the gastrointestinal tract under normal circumstances. Sources meats, fish, and dairy products are good dietary sources of niacin. The roasting of coffee beans results in the release of significant quantity of niacin as well as in the development of a characteristic flavor. Tryptophan is also converted to niacin in the body. Uses of Vitamin B3 1.Niacin acts as coenzyme in energy-transfer reactions 2.Niacin is similar to the riboflavin coenzymes in that it carries hydrogen during metabolic reactions. 3.protects against neurological degeneration and Alzheimer’s disease 4.Helps lower LDL cholesterol 5.lowers risk of cardiovascular diseases and eases arthritis. Deficiency Pellagra is the classic niacin-deficiency condition. Symptoms of the deficiency involve the nervous system, the skin, and the gastrointestinal tract and are sometimes summarized as the 3D's—dementia, dermatitis, and diarrhea. Oral lesions, especially angular stomatitis, , and red tongue, are more distinctive than the other symptoms. Vitamin B5 Pantothenic acid or vitamin B5 is a component of the vitamin B complex that is sometimes known as the "chick antidermatitis factor" (based on a prior bioassay procedure). Pantothenic acid is a naturally occurring compound that on hydrolysis yields B-alanine and pantoic acid, a substituted butyric acid derivative. Sources: Animal organs (heart, kidney, and liver) and cereal grains are rich dietary sources of pantothenic acid. Uses of vitamin B5 1. turn the food into the energy 2.involved in the synthesis of lipids, neurotransmitters, steroid hormones, and hemoglobin. 3.maintenance and repair of tissues and cells of the skin and hair 4.helps in healing of wounds and lesions 5.normalizes blood lipid profile Deficiency causes fatigue and sleep disturbances Vitamin B6 Vitamin B6 is a term that is applied to pyridoxol, pyridoxal, and pyridoxamine, three closely related, naturally occurring, highly substituted pyridine derivatives with comparable physiologic activity. Pyridoxine is the term that is usually used for pyridoxol in pharmacy and medicine. This alcohol is the predominant form of the vitamin in plant materials. Pyridoxal and pyridoxamine occur in animal tissues. Because pyridoxine is the most stable of these substances, synthetically prepared pyridoxine is the material usually used for exogenous dietary supplementation and therapeutic purposes. Sources: Beef liver. Tuna. Salmon. Fortified cereals. Chickpeas, Poultry.  Some vegetables and fruits, especially dark leafy greens, ananas,  papayas, oranges, and cantaloupe. Uses of vitamin B6 1.Improve Mood 2.Vitamin B6 is required for biological reactions (amino acid metabolism, neurotransmitter synthesis, red blood cell formation). 3.Acts as a critical co-factor for a diverse range of biochemical reactions that regulate basic cellular metabolism. Deficiency causes peripheral neuropathy Symptoms of vitamin B deficiency somewhat resemble those of niacin and riboflavin deficiencies. They include neurology abnormalities, skin lesions, and hypochromic microcytic anemia. Vitamin B7 Source: Foods that contain the most biotin include eggs, fish, meat, seeds, nuts, and certain vegetables (such as sweet potatoes) Uses of Vitamin B7 1.Biotin plays an important role in metabolism as a coenzyme that transfers carbon dioxide. 2.This role is critical in the breakdown of food (carbohydrates, fats and proteins) into energy. 3.Biotin is involved in many cellular reactions, particularly in fat and protein metabolism of hair roots, finger nails, and skin. 4.Used in fatty acid synthesis Deficiency causes Fatigue, depression and dermatitis Vitamin B9 Folic acid, folacin, pteroylglutamic acid, and occasionally vitamin B 9 are terms that refer to a material with antianemia properties sources: Beans. Peanuts. Sunflower seeds. Fresh fruits, fruit juices. Whole grains. Liver. Uses of Vitamin B9 1.Folate is essential for brain development and function. 2. It aids in the production of DNA and RNA 3.metabolism of vitamins and amino acids 4. The nutrient is crucial during early pregnancy to reduce the risk of birth defects of the brain and spine 5.Required for synthesis of glycine, methionine, nucleotides T & U Deficiency state include megaloblastic and macrocytic anemias and glossitis. Vitamin B12 Vitamin B1 (cobalamins) are terms that refer to a series of porphyrin- related corrinoid derivatives that function as extrinsic factors to prevent pernicious anemia. Cyanocobalamin, a red crystalline material, is the most stable of the cobalamins; consequently, it is the form of vitamin B2 most frequently utilized in therapy. Hydroxocobalamin also finds some therapeutic use; in it the cyano group is replaced with a hydroxyl substituent. Uses of vitamin B12 1.act as a coenzyme in the conversion of homocysteine to methionine, 2.play role in the metabolism of fatty acids and amino acids 3.production of neurotransmitters. 4.maintains a special lining that surrounds and protects nerve fibers 5.bone cell activity depends on vitamin B12. 6.Plays a significant role in DNA synthesis 7.It helps in brain function and synthesis of red blood cells deficiency usually involve rapidly dividing cells of the hematopoietic system (e.g.,megaloblastic anemia) and irreversible neurologic damage (e.g., defective myelin nerve sheaths); they include irritability, weakness, memory loss, mood swings, and a sensation of tingling or numbness of the arms and legs. Vitamin C Vitamin C or L-ascorbic acid is a naturally occurring vitamin substance that pre vents scurvy and has useful antioxidant properties. It occurs in equilibrium with dehydro-L-ascorbic acid, an oxidized form, which also has antiscorbutic properties. Vitamin C is the least stable of all the vitamins. Sources: Good dietary sources of ascorbic acid include citrus fruits, tomatoes, strawberries, and other fresh fruits and vegetables. Although the vitamin content is preserved on freezing, up to 50% of the vitamin C content is lost upon cooking. Uses of vitamin C 1.One of the important properties is antioxidant activity. 2. functions in enzyme activation and oxidative stress reduction 3.play roles in the synthesis of collagen and absorption of iron 4.defense against infections and inflammation 5.helps to prevent certain diseases such as cancer, common cold, cardiovascular diseases and cataract. Vitamin C deficiency causes scurvy