Vitamins Part 2 PDF

WATER-SOLUBLE VITAMINS B-complex Vitamins Vitamin B1 Thiamine or vitamin B1 has subs tuted 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....

WATER-SOLUBLE VITAMINS B-complex Vitamins Vitamin B1 Thiamine or vitamin B1 has subs tuted 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 es mated that about 50% of the vitamin in foods is destroyed during cooking. ti ti  Source: Whole grains, legumes, and meats are good dietary sources of thiamine. Although the substance is absorbed readily from the small intes ne, alcohol inhibits its absorp on. Uses of Vitamin B1 1. Thiamin is a sulfur-containing vitamin that par cipates in energy metabolism 2. conver ng carbohydrates, lipids and proteins into energy. 3. plays a key role in nerve and muscle ac vity. 4. Thiamin may be helpful to people with Alzheimer disease. 5.Development of myelin sheaths and improves brain func on Vitamin B1 (thiamine) de ciency cause of several clinical syndromes, including Wernicke, encephalopathy, beriberi. Risk factors include alcohol dependence, malabsorp on, and a diet low in thiamine (e.g., based on polished rice).  ti ti ti fi ti ti ti ti  Beri beri Vitamin B2 Ribo avin or vitamin B 2 is a yellow, heat-stable substance that is slightly soluble in water. It is sensi ve to light and will change into lumichrome or lumi avin, depending on whether the irradiated solu on is acidic or alkaline; neither lumichrome nor lumi avin possesses physiologic ac vity.  fl fl ti fl ti ti  Sources: Yeast is the richest natural source of ribo avin. 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. Ribo avin is stable during cooking in the absence of light. Ribo avin occurs in foods in the free form and as ribo avin 5'- phosphate (Flavin mononucleo de or FMN) and avin adenine dinucleo de (FAD). The nucleo des are hydrolyzed to ribo avin in the upper gastrointes nal tract. Free ribo avin is absorbed readily into cells of the intes nal mucosa by an ac ve transport system that is enhanced by bile salt. Uses of Vitamin B2 1. Coenzyme func ons in numerous oxida on-reduc on reac ons which are necessary for releasing energy from carbohydrates, fats and proteins. 2. s mulates growth and reproduc on 3. plays a role in vision 4. plays a role in conversion of vitamins B6, folic acid, and niacin into their ac ve coenzyme forms. 5. neutralizes free radicals hence acts as an -oxidant De ciency causes stoma s and derma s ti fi ti fl ti ti ti ti ti ti ti ti ti ti ti ti fl fl ti ti fl fl ti ti fl fl  vitamin B3 Niacin, nico nic acid, or vitamin B3 is a simple, naturally occurring pyridine deriva ve that prevents pellagra. Niacinamide or nico namide also occurs naturally, has an pellagra ac vity, and is used for dietary and therapeu c purposes. They are readily absorbed from the gastrointes nal tract under normal circumstances. Sources meats, sh, and dairy products are good dietary sources of niacin. The roas ng of co ee beans results in the release of signi cant quan ty of niacin as well as in the development of a characteris c avor. Tryptophan is also converted to niacin in the body. Uses of Vitamin B3 1. Niacin acts as coenzyme in energy-transfer reac ons 2. Niacin is similar to the ribo avin coenzymes in that it carries hydrogen during metabolic reac ons. ti fi ti ti ti ti ti ti fl ff ti fl ti ti ti ti fi  3. protects against neurological degenera on and Alzheimer’s disease 4. Helps lower LDL cholesterol 5. lowers risk of cardiovascular diseases and eases arthri s. De ciency Pellagra is the classic niacin-de ciency condi on. Symptoms of the de ciency involve the nervous system, the skin, and the gastrointes nal tract and are some mes summarized as the 3D's—demen a, derma s, and diarrhea. Oral lesions, especially angular stoma s, , and red tongue, are more dis nc ve than the other symptoms. Vitamin B5 Pantothenic acid or vitamin B5 is a component of the vitamin B complex that is some mes known as the "chick an derma s factor" (based on a prior bioassay procedure). Pantothenic acid is a naturally occurring compound that on hydrolysis yields B-alanine and pantoic acid, a subs tuted butyric acid deriva ve. Sources: Animal organs (heart, kidney, and liver) and cereal grains are rich dietary sources of pantothenic acid. fi fi ti ti ti ti ti ti fi ti ti ti ti ti ti ti ti ti ti ti ti  Uses of vitamin B5 1. turn the food into the energy 2.involved in the synthesis of lipids, neurotransmi ers, steroid hormones, and hemoglobin. 3.maintenance and repair of ssues and cells of the skin and hair 4.helps in healing of wounds and lesions 5.normalizes blood lipid pro le De ciency causes fa gue and sleep disturbances Vitamin B6 Vitamin B6 is a term that is applied to pyridoxol, pyridoxal, and pyridoxamine, three closely related, naturally occurring, highly subs tuted pyridine deriva ves with comparable physiologic ac vity. 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 ssues. Because pyridoxine is the most stable of these substances, synthe cally prepared pyridoxine is the material usually used for exogenous dietary supplementa on and therapeu c purposes. ti fi ti ti ti ti fi ti tt ti ti ti  Sources: Beef liver. Tuna. Salmon. For ed 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 reac ons (amino acid metabolism, neurotransmi er synthesis, red blood cell forma on). 3. Acts as a cri cal co-factor for a diverse range of biochemical reac ons that regulate basic cellular metabolism. De ciency causes peripheral neuropathy Symptoms of vitamin B de ciency somewhat resemble those of niacin and ribo avin de ciencies. They include neurology abnormali es, skin lesions, and hypochromic microcy c anemia. Vitamin B7 Source: Foods that contain the most bio n include eggs, sh, meat, seeds, nuts, and certain vegetables (such as sweet potatoes) fi fl ti tt fi fi ti fi ti ti ti ti fi ti ti  Uses of Vitamin B7 1. Bio n plays an important role in metabolism as a coenzyme that transfers carbon dioxide. 2. This role is cri cal in the breakdown of food (carbohydrates, fats and proteins) into energy. 3. Bio n is involved in many cellular reac ons, par cularly in fat and protein metabolism of hair roots, nger nails, and skin. 4. Used in fa y acid synthesis De ciency causes Fa gue, depression and derma s Vitamin B9 Folic acid, folacin, pteroylglutamic acid, and occasionally vitamin B 9 are terms that refer to a material with an anemia proper es  ti ti fi tt ti ti fi ti ti ti ti ti ti  sources: Beans. Peanuts. Sun ower seeds. Fresh fruits, fruit juices. Whole grains. Liver. Uses of Vitamin B9 1. Folate is essen al for brain development and func on. 2. It aids in the produc on 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, nucleo des T & U De ciency state include megaloblas c and macrocy c anemias and glossi s. Vitamin B12 Vitamin B12 (cobalamins) are terms that refer to a series of porphyrin- related corrinoid deriva ves that func on 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 B12 most frequently u lized in therapy. Hydroxocobalamin also nds some therapeu c use; in it the cyano group is replaced with a hydroxyl subs tuent. fi ti ti ti ti ti fl ti ti ti ti ti ti ti fi  Uses of vitamin B12 1. act as a coenzyme in the conversion of homocysteine to methionine, 2. play role in the metabolism of fa y acids and amino acids 3.produc on of neurotransmi ers. 4. maintains a special lining that surrounds and protects nerve bers 5. bone cell ac vity depends on vitamin B12. 6. Plays a signi cant role in DNA synthesis 7. It helps in brain func on and synthesis of red blood cells de ciency usually involve rapidly dividing cells of the hematopoie c system (e.g.,megaloblas c anemia) and irreversible neurologic damage (e.g., defec ve myelin nerve sheaths); they include irritability, weakness, memory loss, mood swings, and a sensa on of ngling or numbness of the arms and legs.  fi ti ti ti fi ti ti tt tt ti ti fi ti  Vitamin C Vitamin C or L-ascorbic acid is a naturally occurring vitamin substance that pre vents scurvy and has useful an oxidant proper es. It occurs in equilibrium with dehydro-L-ascorbic acid, an oxidized form, which also has an scorbu c proper es. 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 proper es is an oxidant ac vity. 2. func ons in enzyme ac va on and oxida ve stress reduc on 3. play roles in the synthesis of collagen and absorp on of iron ti ti ti ti ti ti ti ti ti ti ti ti ti ti  4. defense against infec ons and in amma on 5. helps to prevent certain diseases such as cancer, common cold, cardiovascular diseases and cataract. Vitamin C de ciency causes scurvy fi ti fl ti