Physiological function of vitamin e
Brief introduction of vitamin e
Vitamin E, also known as tocopherol, is a fat-soluble vitamin, which mainly exists in vegetables and beans, and is the most abundant in wheat germ oil. There are 8 kinds of naturally occurring vitamin E, all of which are derivatives of benzodihydropyran. According to its chemical structure, it can be divided into tocopherol and tocotrienols (Figure 12), and each class can be divided into four types according to the number and position of methyl groups. α-tocopherol has the highest physiological activity among commercially available vitamin E, while the physiological activities of β-tocopherol, γ-tocopherol and α-triene tocopherol are only 40%, 8% and 20% of α-tocopherol. Vitamin E is a slightly viscous light yellow oil, which is relatively stable under oxygen-free conditions and will not be destroyed even if it is heated above 200℃. However, in the air, vitamin E is easily oxidized and its color becomes darker. Vitamin E is easily oxidized, so it can protect other substances that are easily oxidized (such as vitamin A and unsaturated fatty acids) from being destroyed. Vitamin E in food is mainly absorbed in the upper small intestine of animals, and is mainly carried by β -lipoprotein in blood and transported to various tissues. Isotope tracing experiments show that α -tocopherol can be oxidized into α -tocoquinone in tissues. The latter can combine with glucuronic acid in the liver, enter the intestine with bile, be reduced to α-reproductive hydroquinone, and then be excreted through feces. The metabolism of other vitamin E is similar to that of α-tocopherol. Vitamin e is necessary for animal reproduction. When vitamin E is deficient, the testis of male rats degenerates and normal sperm cannot be formed. Female mouse embryos and placenta atrophy and are absorbed, which will cause abortion. Lack of vitamin E in animals may also lead to muscle atrophy, anemia, encephalomalacia and other neurodegenerative diseases. If accompanied by protein deficiency, it will cause acute liver cirrhosis. Although the metabolic mechanism of these diseases has not been fully clarified, the multiple functions of vitamin E may be related to its antioxidant effect. The symptoms of some human diseases are similar to those of animals lacking vitamin E. Because the content of vitamin E in general food is still sufficient and easy to be absorbed, vitamin E deficiency is not easy to occur, and it is only seen in the absorption of lipids in the intestine. Vitamin E is widely used in clinic, and it has been found that it can prevent and treat some diseases, such as atherosclerosis, muscular dystrophy, brain edema, male and female infertility, threatened abortion and so on. In recent years, vitamin E has been used to prevent aging. Vitamin E was discovered by American chemist Evans in 1922 and extracted from malt oil. It was synthesized artificially in the 1940s. 1960 China has been ready for mass production. It is odorless and tasteless liquid, insoluble in water and soluble in organic solvents such as ether. Its chemical properties are stable, heat-resistant, acid-resistant and alkali-resistant, but it is easy to be destroyed by ultraviolet rays, so it should be kept in a brown bottle. Vitamin E is an excellent antioxidant in human body. Without it, both men and women can't have children, and in severe cases, their muscles will atrophy and their nerves will be numb.
Daily demand
The daily requirement of vitamin E for adults is not clear, but the results of animal experiments show that 50 mg of food per day can meet the needs. The demand for pregnancy and breastfeeding has increased slightly. Four spoonfuls of sunflower seed oil, 100 mg of olive oil, 100 g of peanuts or 30 g of almonds and 70 g of walnuts contain vitamin e needed for one day. Efficacy: Vitamin E can resist the invasion of free radicals and prevent myocardial infarction caused by cancer. In addition, it also participates in the formation of antibodies and is a true "descendant supporter". It promotes men to produce energetic sperm. Vitamin E is a strong antioxidant, and insufficient supply of vitamin E will cause various mental or emotional disorders. Side effects: Taking 200 mg of vitamin E every day can cause nausea, muscle atrophy, headache and fatigue. Taking more than 300 mg of vitamin E every day can lead to high blood pressure, delayed wound healing and limited thyroid function.