What is Hesperidin and How it is extracted
Hesperidin has the functions of maintaining osmotic pressure, enhancing capillary toughness, shortening bleeding time, and lowering cholesterol. It is clinically used in the adjuvant treatment of cardiovascular diseases. It can cultivate a variety of drugs to prevent arteriosclerosis and myocardial infarction. It can be used as a natural antioxidant in the food industry. It can also be used in the cosmetics industry. Hesperidin is mostly found in the wastes of citrus processing, such as peels, fruit sacs, and the content of hesperidin in mature peels and tissues* (endocarp 30%-50%, orange network, stone, pulp 30%-50% in the middle, 10%-20% in the exocarp), and 1%-5% in the juice and orange sac.
The extraction methods of hesperidin include solvent extraction, alkali extraction and acid precipitation, carbon powder adsorption, and ion exchange. Among them, the alkali extraction and acid precipitation method is widely adopted with simple operation, low cost and high yield rate. Hesperidin is soluble in dilute alkali, pyridine and hot water above 70℃, slightly soluble in methanol, and almost insoluble in acetone, benzene and chloroform.
The extraction of hesperidin is to the two phenolic hydroxyl groups contained in it to react with sodium ions in the solution under alkaline conditions to form sodium salt and dissolve , and then acidify and cool to make it precipitate out of the solution. while hot extraction and soaking extraction of hesperidin from citrus peel are not with impressive hesperidin outcome.
In recent years, ultrasonic extraction of active ingredients from natural plants (especially Chinese herbal medicines) has been extensively used, and certain progress has been made. Use hesperidin for extraction under alkaline conditions by ring cleavage dissolution, and separation under acidic conditions by closed-ring precipitation. Increasing alkali usage during extraction can reduce the amount of ethanol, but the alkalinity should not be too large, otherwise, hesperidin is easy to be oxidized.