Quality Analysis Of Flavonoid Glycosides In Oral Preparations Of Ginkgo Biloba And Ginkgo Biloba Extract

Ginkgo Folium is dry leaf of the Ginkgo biloba L..The preparations made from by Ginkgo biloba leaves or ginkgo biloba leaf extract have been important products of modern botanical drugs which occupy a larger market share.Unforturnately,there are often negative reports about quality of these products.One of the most useful measures is to improve the quality control level of the current standard.This thesis mainly focused on flavonoid glycosides which are one of the main active ingredients in Ginkgo biloba leaves.We hope to establish more effective,simple and feasible quality control methods by use of fingerprints,Quantitative Analysis of Multi-components by Single-marker(QAMS)and ginkgo biloba leaf extract.As the total flavonoids glycosides composition is not fully elucidated and deficiency of standard substance,in the current domestic and foreign standard,the content of total flavonol glycosides is usually indirectly calculated by using acid hydrolysis method.Although this method can solve the problem of lack of standards substance,the quality control is not accurate,and provides the possibility for the artificial addition of flavonoid aglycone and other adulteration.On the basis of previous studies,original flavonoid glycosides have been used to determine the contentof these compounds in the Ginkgo biloba oral preparations including tablet,capsule,tincture,drop,dropping pill and soft capsuleby using fingerprint.Qualitative analysis was carried out by using similarity evaluationand ratio of characteristic flavonoid glycoside peak area.All of the qualified products should be accomplied with similarity>0.90,while the peak area ratio((KRG + QRcG + KRcG)/Rutin)>1.60.In order to solve the problem of absent commercial reference substance of the Ginkgo biloba flavonoid glycosides,a new QAMS method was also established on the basis of quantitive studies.Rutin was selected as an internal reference and the other five flavonoid glycosides were calculated by using relative correction factors to rutin.The reference flavonoid extract of Ginkgo biloba leaves was prepared and used to determine the content of flavonol glycosides in oral preparations of Ginkgo biloba.The content of flavonol glycosides in the official reference extract of Ginkgo biloba leaves from NIFDC was also calculated and used to determine the content of flavonol glycosides in oral preparations of Ginkgo biloba.The differences among results of flavanol glycosides in oral preparations by using above four methods have been analyzed and there were few abvious difference among the four methods(P>0.05),indicating that the four methods can be used equally in quantitative analysis of flavonol oral preparation of Ginkgo biloba.This thesis also explored seasonal variation of 6 flavonol glycosides in Ginkgo biloba leaves collected in Beijing from May to October,2016.That totally 162 pieces with same age and different sexuality of three districts in Beijing,the result showed that along with seasons changing,tendency of composition and content is same with it basically,that is to say,composition changing status of others three types flavonol glycosides Rutin?KGR?IGR are same basically,fallen in June and July,rose in August,kept higher level on October although fluctuation.The composition and changing status of others three types flavonol glycosides KRG?QRcG?KRcG are same basically,in the whole growth cycle,although there is fluctuation and changing in each month,but there is not big changing and kept smoothly.There is deference composition between female and male Ginkgo biloba,six types of flavonol glycosides composition of male Ginkgo biloba are higher than female.There is a little difference in appearing months of male and female Ginkgo biloba's maximum flavonol glycosides composition in three districts,among them,female Ginkgo biloba of it appeared in May,August and October,male of it appeared in May and October.The above research and results provide a simple,durable and feasible new method for the quality control of Ginkgo biloba and its oral preparations,and improve the quality control level of Ginkgo biloba leaves and its oral preparations.