The Extraction And Separation Flavone Components From Luohanguo Leaves

Luohanguo[[Momordica grosvenori swingle] , is a Siraitia grosvenon plant, It has moisturizing lung,dispelling Phlegm and relieving cough virtues. So it is used widely in manufacturing medicine, beverage and flavoring. Predecessors mainly are focused on luohanguo fruits and luohanguo leaves are researched very few. This essay studies luohanguo leaves from the flowing five faces. 1. Luohanguo leaves contain amino acid,tea polyphenons,flavonoids and such like by qualitative analysis. Amino acid content is determined by ninhydrine colorimetry. Tea polyphenons and ferrous ion can form purple complex, its content is determined by spectrophotometer in 570nm and 540nm. The result shows amino acid content is 5.82%,tea polyphenons content is 1.61%. 2. The coarse flavone is extracted from luohanguo leaves by boiling water, collected by resin adsorption, elutriated by 75% ethanol. The refined flavone is obtained by absolute alcohol purification. The content of total flavonoids is measured by external standard method. The result shows that the coarse flavone is 26.8% and the refined flavone is 57.8%. 3. Quercetin and kaempferol are found from luohanguo leaves by their Retain-time in RP-HPLC. Their monomers are gained by silica gel column chromatography. Three flavonol glycosides are isolated from luohanguo leaves with gradient elution of chloroform:methanol:water(50:10:1~ 30:30:1), many times silica gel column chromatography and HPLC purification. Two flavonol glycosides'structures are verified by different kinds of spectrum and chemistry methods. They are quercetin-3-O-β-D-glucose-7-O-α-L-rhamnopyranoside, and kaempferol-3,7-O-α-L-dirha-mnopyranoside 4. The criterion of luohanguo flavone is composed according to gingkgo flavone criterion. The content is measured for the coarse flavone and refined flavone from the industry manufactured expriment. The result shows that the coarse flavone is 33.24% and the refined flavone is 42.29%. 5. The experiment result demonstrates that luohanguo has a lot of pharmacody functions, for instance:resisting thrombus form,repelling blood platelet conglomeration,falling blood fat,contradicting cruor,promoting blood circulation and absorbing clots, and so on. They provided preliminary scienced reference for empoldering and applying luohanguo flavone in the future. Pharmacody functions in other faces still need to research furtherly .