第七章 维生素--王镜岩《生物化学》第三版笔记(完美打印版)文库（The seventh chapter is vitamin - Wangs biochemistry third edition notebook (perfect print edition) library）.docVIP

第七章 维生素--王镜岩《生物化学》第三版笔记(完美打印版)文库（The seventh chapter is vitamin - Wangs biochemistry third edition notebook (perfect print edition) library） The first section is an overview I. definitions Vitamins are small molecules of nutrients necessary for the organism. In 1894 the Dutch Ejkman chicken with rice beriberi observed phenomenon, later Polish Funk from rice bran found compounds containing this disease has curative effect, named vitamine, meaning the vital amine. Later found that not all vitamins are amine, so remove the final e, become Vitamin. Vitamins have the following characteristics: 1. are small molecules with different structures; 2. needs little; 3. can not be synthesized or synthesized in vivo, and must be ingested directly or indirectly from food; 4., the main function is to participate in the synthesis of active substances (enzymes or hormones) without energy and structure. Water soluble vitamins often act as coenzyme precursors and play a supporting role. Fat soluble vitamins participate in the composition of some active molecules, such as VA, which constitute rhodopsin, and VD constitute hormones regulating the metabolism of calcium and phosphorus. Two, classification The structure of vitamin is different, it is generally divided into two categories: fat soluble and water soluble. Fat soluble vitamins are insoluble in water, soluble in organic solvents, coexist with lipids in food, and are absorbed together with lipids. Difficult to excrete and accumulate in the body (mainly in the liver). They include vitamin A (A1, A2), D (D2, D3), E (alpha, beta, gamma, delta), K (K1, K2, K3), and so on. Water soluble vitamins easily soluble in water, easy to absorb, can be excreted with urine, generally not accumulation in the body, easy to lack. Includes B vitamins and vitamin C. Three, naming Although vitamins are small molecules, but the structure is more complex, general chemical system is not named. Early by the order of discovery and origin by letters and numb