Study On The Determination Of Flavonoids From Ginkgo Biloba Foods

Ginkgo biloba was also called white fruitage tree, and it was one of the higher plants, which had the longest life. The Ginkgo biloba leaves mainly included some effective constituents, such as flavonoids and ginkgolides, which can aggrandize the blood vessel, increase the outflow of blood, improve the kinetic of blood-circulating, decrease the resisting force of cerebrovascular, and suppress thrombosis and clean free radical of human body.Flavonoid was one kind of components with a wide range of bioactivities in Ginkgo biloba and now had become a hot research issue noticed by scientists of many countries.High-performance liquid chromatography (HPLC) was a form of column chromatography used frequently in biochemistry and analytical chemistry to separate, identify, and quantify compounds. HPLC frequently provided specific, selective and sensitive quantitative results, which had became one of the major tools in food analysis.In this experiment, we used HPLC method to separate and analyze the flavonoid in ginkgo foods. Eclipse XDB C18(250mm×4.6mm,5μm) column which had a good separation effect of flavonoids was chosen for analyzing with methanol-0.4%phosphoric acid (60:40) as mobile phase. All peaks had a good separation and moderate retention time. Analyzed the200-400nm full wavelength scan figure of Quercetin、Isorhamnetin and Keampferol standards, and using360nm as the detecting wavelength of flavonoids.The experimental results show that it was feasible to use HPLC to detect flavonoid such as Quercetin, Kaempferol,and Isorhamnetin. The method is simple, accurate and can meet the practical test needs.Water extraction, ultrasonic extraction, and organic solvent extraction were used respectively for extracting flavonoids in ginkgo biloba tea. The results showed that organic solvent extraction obtain the best outcomes. Then three organic solvents were selected for extracting flavonoids. We identified methanol as the extracting solvent.When methanol extraction method was investigated for extracting flavonoids in ginkgo biloba tea, a group of L9(34) orthogonal experiments were performed to study the effect of three factors, such as the added amount of hydrochloric acid, extraction temperature, and extraction time. Base on the results, we got the order of three factors’ influence on flavonoids extraction. And the results also indicated best efficiency was obtained under the condition of added4mL25%hydrochloric acid, and extract for90min when heated at100℃.This study was about the determination of flavonoids in ginkgo foods such as ginkgo crystal, ginkgo wine and ginkgo energy drinks. The testing procedure was simple, accurate and easy to master. It was good news for Ginkgo foods supervision.