Biochemistry

Vitamin E deficiency in the body can occur with diseases of the liver, pancreas, intestines, as well as with an excess of polyunsaturated fatty acids in the diet, vitamin A and animal protein deficiency. Daily intake of vitamin E is 10-20 mg for adults and 0.5 mg / kg of body weight for children. The need for it increases with diseases of reproductive and neuromuscular systems, in those working conditions of oxygen deficiency, in heavy physical labor, in athletes. Sources. Rich sources of vitamin E are vegetable oils (sunflower, soybean, cottonseed, com), green leaves of vegetables, egg yolks. A tocopherol absorption in the intestine requires the presence of fats in food. Phylloquinones (vitamin K, coagulation factor). An observation was made indicating the existence of a special vitamin that regulates blood coagulation in 1929. Later, two natural vitamins were discovered: К i and К 2 , which turned out to be derivatives of naphthoquinone. Vitamin К was synthesized in 1939. Structure and physicochemical properties. Vitamin К is a yellowish oily liquid. It is insoluble in water, very unstable when heated in an alkaline environment and when irradiated. 0 U xCH 3 СНз СНз V V х сн 2 -сн « 1 =С-[СН 2 -СН 2 -СН 2 -СН]з сн 3 0 Phylloquinone (Vitamin Ki) fi 0 xCH s СНз V 4 {CH 2 -CH=C-CH 2 )e-H 0 Metaquinone (Vitamin Кз) Vitamin К i has the greatest physiological activity. In addition to vitamins Ki and K 2 , many naphthoquinone derivatives have a similar physiological effect. The Soviet scientist A.V. Palladine synthesized an aqueous analogue of vitamin К - vikasol in 1942. It is a colorless, finely crystalline powder soluble in water. Biological role. Phylloquinone is involved in prothrombin synthesis - a protein that provides blood coagulation, therefore it is called the antihemorrhagic 268