Water Soluble Vitamins:
Biotin (Vitamin B7):
Biotin (Vitamin B7) acts as a co-enzyme for carboxylation reactions essential to fat and carbohydrate metabolism. Adequate intake for adults is 30 μg/day. the sources of the vitamin are Liver, egg yolks, green vegetables. Whole grains are rich sources of biotin.
Structure of Biotin
Folic Acid (Vitamin B9):
Folate, also called Vitamin B9, is involved in maturation of red blood cells and the synthesis of purines and pyrimidines which are required for the development of the fetal nervous system. Adequate folic acid intake before conception and throughout the first trimester of pregnancy helps prevent certain brain and spinal cord defects such as spina bifida. Folate is absorbed in the duodenum and upper jejunum. The US recommended daily dose for folate is 400 μg and the upper limit is 1000 μg. Folate is essentially nontoxic. Deficiency produces megaloblastic anemia indistinguishable from that due to vitamin B12 deficiency. A deficiency of folate in old age significantly increases the risk of developing dementia.
Folic acid foods: Folic acid is found in dried peas, dried beans, yeast, and leafy green vegetables such as spinach, endive, lettuce, and mustard greens.
Structure of Folic acid
Niacin (Vitamin B3):
Niacin (Vitamin B3 or nicotinic acid) derivatives include nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), which are coenzymes in oxidation-reduction reactions vital in cell metabolism.
Dietary niacin deficiency causes pellagra, a disease characterized by dermatitis, gastrointestinal disorders, and mental disturbances. Primary deficiency results from extremely inadequate intake of both niacin and the amino acid tryptophan, which usually occurs in areas where maize (Indian corn) constitutes a substantial part of the diet. Mushrooms and fish are good sources of niacin.
Structure of Niacin Molecule
Pantothenic Acid (Vitamin B5):
Pantothenic acid (Vitamin B5) is widely distributed in foods, and high amounts are found in whole grain cereals, legumes, eggs, and meat. Pantothenic acid is needed to form coenzyme-A (CoA) and is critical in the metabolism and synthesis of carbohydrates, proteins, and fats. Adults require about 5 mg/day.
Pantothenic acid foods: Pantothenic acid is found in mushrooms, yeast, and liver.
Structure of Pantothenic acids
Riboflavin (Vitamin B2):
Riboflavin (Vitamin B2) is involved in carbohydrate metabolism as an essential coenzyme in many oxidation-reduction reactions. Riboflavin is essentially nontoxic. Riboflavin deficiency usually occurs with other B-vitamin deficiencies. Symptoms and signs include sore throat, lesions of the lips and mucosa of the mouth, glossitis, conjunctivitis, seborrheic dermatitis, and normochromic-normocytic anemia. Riboflavin is found in mushrooms, yeast, and meats such as beef, pork, and lamb.
Structure of Riboflavin
Thiamine (Vitamin B1):
Thiamine or Thiamine (vitamin B1) is widely available in the diet. Thiamine is involved in carbohydrate, fat, amino acid, glucose, and alcohol metabolism. Thiamine is essentially nontoxic. Thiamine deficiency (causing beriberi) is most common among people subsisting on highly refined rice or other carbohydrates in developing countries. Bean sprouts, brewer’s yeast, and fortified cereals are good sources of thiamine.
Structure of Thiamin
Vitamin B12 (Cyanocobalamine):
Cobalamin is a general term for compounds with biologic vitamin B12 activity. These compounds are involved in nucleic acid metabolism, methyl transfer, and myelin synthesis and repair. They are necessary for the formation of normal red blood cells.
Vitamin B12 is released in the stomach’s acid environment and is bound to R protein. Pancreatic enzymes cleave the B12-R protein complex in the small intestine. After cleavage, intrinsic factor, secreted by parietal cells in the gastric mucosa, binds with vitamin B12.
Intrinsic factor is required for absorption of vitamin B12, which takes place in the terminal ileum. The Recommended Dietary Allowance (RDA) is 2.4 micrograms, which is the amount found in 3 ounces (85 grams) of meat.
Vitamin B12 is found in clams, oysters, turkey, chicken, beef, and pork. Dietary vitamin B12 deficiency usually results from inadequate absorption, but deficiency can develop in vegans who do not take vitamin supplements.
Deficiency causes megaloblastic anemia, damage to the white matter of the spinal cord and brain, and peripheral neuropathy which is characterized by tingling or numbness in the hands or feet.
Structure of Cyanocobalamine
Vitamin B6 includes a group of closely related compounds: pyridoxine, pyridoxal, and pyridoxamine. They are metabolized in the body to pyridoxal phosphate, which acts as a coenzyme in many important reactions in blood, central nervous system, and skin metabolism.
Vitamin B6 is important in the biosynthesis of heme and nucleic acid, as well as in lipid, carbohydrate, and amino acid metabolism. Vitamin B6 is found in a variety of vegetables and meats.
Many breakfast bowls of cereal are fortified with Vitamin B6. Some natural sources of Vitamin B6 are brewer’s yeast, Chinese cabbage (Pak Choi), and red and green peppers.
Structure of Pyridoxine
Vitamin C (ascorbic acid) plays a role in collagen, carnitine, hormone, and amino acid formation. It is essential for wound healing and facilitates recovery from burns.
Vitamin C is also an antioxidant, supports immune function, and facilitates the absorption of iron. In developed countries, deficiency can occur with general undernutrition, but severe deficiency (causing scurvy) is uncommon.
Symptoms of deficiency include fatigue, depression, and connective tissue defects such as gingivitis, rash, internal bleeding, or impaired wound healing. The Recommended Dietary Allowance (RDA) is 75 milligrams for women, 90 milligrams for men.
The tolerable upper intake level of Vitamin C is approximately 2 grams (2000 mg) per day. Higher amounts can cause stomach upset and diarrhea. Vitamin C is found in fresh fruits and vegetables. Citrus fruits like oranges and lemons are good sources of vitamin C.
Structure of Vitamin C (Ascorbic Acid)