What is hesperidin?

Hesperidins (Vitamin P) is a flavonoid substance widely present in citrus fruits, its chemical structure has a dihydroflavonoside structure, is weakly acidic, and the extracted crude product is a light yellow powder. Pure product is white acicular crystal, slightly bitter, insoluble in water, almost insoluble in acetone, benzene, chloroform, slightly soluble in methanol, hot ice acetic acid, soluble in formamide, diformamide, easy to dissolve in dilute alkali solution, purity of 97% hesperidin melting point range of 257~260℃, molecular weight of 610.6. Hesperidin has the functions of maintaining osmotic pressure, enhancing capillary toughness, shortening bleeding time, lowering cholesterol, etc. It is clinically used in the adjuvant treatment of cardiovascular system diseases, and can cultivate a variety of drugs to prevent arteriosclerosis and myocardial infarction. It is one of the main raw materials of the patent medicine “Maitong”. It is used as a natural antioxidant in the food industry. It can also be used in the cosmetics industry. Hesperidin mostly exists in citrus processing waste, if the peel, fruit sac, among which the mature peel and tissue of hesperidin content is the highest (inner peel 30%-50%, orange, core, pulp 30%-50%, outer peel 10%-20%), juice and orange sac content is lower 1%-5%. The extraction methods of hesperidin include solvent extraction, alkali extraction and acid precipitation, carbon powder adsorption and ion exchange, among which alkali extraction and acid precipitation is simple, low cost and high extraction rate. Orange peel can dissolve in dilute alkali and pyridine and hot water above 70℃, slightly soluble in methanol, almost insoluble in acetone, benzene and chloroform. The extraction of hesperidin mainly uses the two phenolic hydroxyl groups contained in it to react with sodium ions in the solution under alkaline conditions to form sodium salts and dissolve them, and then acidize and cool them to precipitate them from the solution. Hesperidin was extracted from citrus peel by heat extraction and soaking extraction, but the yield was not satisfactory. In recent years, ultrasonic extraction of active components from natural plants (especially Chinese herbal medicine) has been widely carried out and has made some progress. Hesperidin is extracted by open-loop dissolution under alkaline conditions and separated by closed-loop precipitation under acidic conditions. Increasing the amount of alkali during extraction can reduce the amount of ethanol, but the alkalicity should not be too large, otherwise hesperidin is easy to be destroyed by oxidation.