Method for preparing quercetin from tung tree leaf

Abstract

The invention discloses a method for preparing quercetin from tung tree leaves. The method comprises the following steps: crushing tung tree leaves, putting into an ultrasonic preparation container, adding an alcohol solution of a certain concentration, performing ultrasonic intensified extraction, and concentrating; putting an acid solution into the concentrated liquid, and performing hydrolysis;adjusting the pH value of hydrolysate by using an alkali liquid till the hydrolysate is neutral; extracting with ethyl acetate, concentrating, drying, performing medium pressure MCI column spectrum and polyamide column spectrum separation on the obtained extract, and performing purification with Sephadex LH-20 gel and a silica gel column spectrum, thereby obtaining a quercetin product of which the content is 95% or greater. The method has the advantages of being simple in equipment process, small in energy consumption, high in extraction efficiency, and the like, selected chromatography materials MCI, polyamide and gel can be all repeatedly used, and the method is applicable to industrial production.

Description

technical field [0001] The invention belongs to a method for extracting plant active components, in particular to a method for preparing quercetin from tung tree leaves. Background technique [0002] Tung is a small deciduous tree belonging to Euphorbiaceae, which is rich in resources in my country. It is not only an important dry oil plant, but also a practical medicinal plant. Its roots, leaves, and fruits can be used medicinally, and it has a long history of folk use. Especially tung leaf, "Fujian Folk Herbal Medicine" and "Caomu Recipe" all record that tung leaf has the effect of reducing swelling and detoxification, and can treat carbuncle, erysipelas, scabies, and enteritis. [0003] Quercetin, also known as quercetin, is soluble in glacial acetic acid, the alkaline aqueous solution is yellow, almost insoluble in water, and the ethanol solution tastes very bitter. It can be used as a medicine, which has good expectorant and cough-relieving effects, and has a certain ...

AI Technical Summary

Problems solved by technology

[0005] At present, the preparation method of quercetin has: 1, separates and prepares from natural plant, as methods such as " reclaiming isoquercetin from bioflavonoids " (CN1355797), but this class method will use a large amount of organic solvents, to The environment is polluted, and the yield is low, the cost is high, and it is difficult to realize industrial production

2. Preparation of isoquercetin and quercetin by enzymatic hydrolysis of rutin, such as "Method for preparing isoquercetin and quercetin by enzymatic hydrolysis" (CN03133636.1), "Preparation, purification and Transformation of flavonoid compounds" (CN1685053A), this type of method requires the use of expensive biological enzyme preparations, the process equipment is more complicated, and the production cost is higher

3. The industrial production of quercetin generally adopts the process of hydrolyzing rutin with strong acid (see: Liu Yaping, Research on the preparation method of quercetin, Shi Zhen Guo Yi Guo Yao, 2004, 15 (10): 657-658; He Qin, Xu Xiongliang, etc. , Orthogonal test method to optimize the preparation process of quercetin in Sophora japonica, Chinese herbal medicine, 2003, 34 (5): 409-412), but the anti-corrosion requirements for production equipment are relatively high, and three wastes are easily produced, which is not conducive to environmental protection