VITAMINS
1. Vitamins are micronutrients, biological regulators and metabolic regulators.
2. Vitamins are organic substances which animals need to maintain health, but cannot be synthesized in the body.
3. Vitamins were discovered by Lunin.
4. The term Vitamin' was given by Funk.
5. Study of vitamins is called vitaminology.
6. The alphabetical nomenclature of vitamins was proposed by Drummond.
7. There are about 30 different types of vitamins described so far.
8. The vitamins are generally divided into two major groups:
- fat soluble -A, D, E, and K and
- water soluble - B-complex and C.
FAT SOLUBLE vitamins
I. Vitamin A (Retinol)
1. Discovered by Mc Collum and Davis in 1913.
2. Can be synthesized in liver from yellow and red carotenoid pigments.
3. A good source is carrot.
4. Forms the retinal pigments such as rhodopsin of rod cells and iodopsin of cone cells of the retina.
5. Maintains normal, living secretory epithelia in mucous membranes and glands.
6. Deficiency diseases are Nyctalopia (night blindness) and Xerophthalmia.
7. Vitamin A is also known as 'anti-infection' vitamin.
also read :CARBOHYDRATES-PROTEINS-FATS-LIPDS
II. Vitamin D (Calciferol)
1. Synthesized in skin from cholesterol by UV light.
2. Also known as 'sunshine vitamin' or 'anti ricket vitamin'.
3. Good source - Meat, liver and milk.
4. Cod liver and shark liver oil, good soruce for both A and D.
5. Regulate absorption and utilization of calcium and phosphorus.
6. Deficiency diseases. Rickets in children and Osteomalacia in adult.
III. Vitamin E (Tocopherols)
1. Inhibits peroxide formation and thereby prevents the damage of membrane lipids.
2. Commonly called 'antisterility vitamin' or 'beauty vitamin.
3. Deficiency diseases: Sterility (Impotence) and muscular atrophy.
4. Vitamin E removes scars and wrinkles of skin.
IV. Vitamin K (Phylloquinone)
1. Vitamin K is synthesized by bacteria in the colon.
2. Essential for synthesis of prothrombin in liver.
3. Commonly called 'Antihaemorrhagic vitamin'.
4. Deficiency: bleeding, No coagulation or clotting.
WATER SOLUBLE VITAMINS
I. Thiamine (Vitamin B12)
1. Discovered by Eijkman
2. Source - whole wheat flour
3. Thiamine operates in the metabolic systems of the body principally as thiamine pyrophosphate for utilization of pyruvic acid.
4. Deficiency diseases: Beri-beri , Polyneuritis.
5. Beri-beri affects the peripheral nervous system, alimentary canal and the cardiovascular system.
II. Riboflavin (Vitamin B2)
1. Combines in the tissue with phosphoric acid to form two coenzymes flavin mononucleotide and flavin adenine dinucleotide.
2. Yellow colour of cow's milk is due to presence of riboflavin.
3. Good sources : Cheese , eggs, yeasts, etc.
4. Deficiency diseases: Dermatitis, sore mouth, ulceration and Cheilosis (disorder of lips and mouth characterized by scales and fissures).
III. Pantothenic acid (Vitamin B3)
1. It is incorporated in the body into coenzyme A (CoA).
2. Vital in synthesis of acetylcholine, the synaptic transmitter.
.3. Source - yeast, liver, eggs, meat etc.
4. Deficiency diseases: Paralysis of muscles and fatigue and burning feet syndrome.
IV. Niacin (Nicotinic acid)
1. It functions in the body as coenzymes inthe form of nicotinamide adenine dinucleotide (NAD) and nicotinamide dinucleotide phosphate (NADP).
2. Vital in synthesis of acetylcholine, the synaptic transmitter.
3. Niacin can be synthesized in the body from the amino acid tryptophan.
4. Deficiency diseases: Pellagra in human beings and black tongue disease in dog.
5. Pellagra is characterised by swollen lips, thick pigmented skin of hands and legs and irritability.
V. Folic acid
1. The most important use in the body is in the synthesis of purines and thymine.
2. Folic acid is required for formation of DNA and replication of cellular genes.
3. Some folic acid is synthesized by bacteria in colon and absorbed from there.
4. Deficiency disease : Megaloblastic anaemia.
VI. Pyridoxine (Vitamin B6)
1. It exists in the form of pyridoxal phosphate in the cell and functions as a coenyzme.
2. It helps in the transamination process for the synthesis of amino acids.
3. Deficiency diseases: Dermatitis and anaemia.
VII. Biotin (Vitamin B7)
1. It is also known as Vitamin H'.
2. It is a sulphur containing coenzyme.
3. Deficiency causes muscular pains.
4. It is essential for fat synthesis.
VIII. Cyanocobalamin (Vitamin B12)
1. It is cobalt containing vitamin.
2. It is present in animal protein such as meat, liver and fishes. Only vitamin not found in vegetables.
3. it acts as a coenzyme for reducing ribonucleotides to deoxyribonucleotides.
4. It promotes DNA synthesis, maturation of RBCs and myelin formation.
5. Intestinal absorption of cobalamin requires the action of a gastric enzyme, secreted by the parietal cells of gastric glands.
6. Deficiency disease: Pernicious anaemia.
IX. Ascorbic acid (Vitamin C)
1. Earliest vitamin known.
2. Rapidly destroyed by heat (also thiamine)
3. Synthesized by Tadeus reichstein.
4. James Lind reported lemon and citrus fruits rich in Vit C.
5. Absent in milk, egg and bread.
6. Generally excreted in urine.
7. Vit. C has virucidal properties.
8. promote wound healing.
9. Smokers and chronic alchoholics suffer from deficiency of this vitamin.
10. Deficiency disease: Scurvy is characterized by spongy and bleeding gums.
MINERALS
The mineral substances required for the body are sodium, potassium calcium, phosphorus, iron and magnesium. They are equally essential for maintaining good health of the body.
Sodium, Potassium and Chlorine
1. Na+ is the principle mineral cation in the extracellular fluid.
2. K+ is the principle cation inside the cell.
3. CI" is the principle mineral anion in the ECF.
4. Na+ and K+ are essential to the maintenance of water balance and acid-base balance.
5. Na+ and K+ are important in nerve impulse transmission.
Calcium and Phosphorus:
1. Calcium and Phosphorus are deposited in bones and teeth to give them strength and rigidity.
2. Ca++ is also essential for blood coagulation, neuromuscular function, cardiac function and actions of many enzymes and hormones.
3. Phosphorus enters into many compounds such as nucleic acids and phospholipids, many coenzymes and high energy compounds like ATP.
4. Calcium plays an essential role in sustaining intestinal peristalsis and growth of body tissues.
Iron:
1. Iron is required for haemoglobin and cytochrome synthesis.
2. Iron is essential both for transportation of oxygen to tissues and for operation of oxidative systems within the tissue cells.
Magnesium:
1. Magnesium is required as a catalyst for many intracellular enzymatic reactions, particularly those relating to carbohydrate metabolism.
2. Low magnesium concentration causes increased irritability of nervous system and peripheral vasodilation.
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