Extraction Of Flavonoids From Ginkgo Biloba Leaves With Alkali Solution And Inclusion Of Flavonoids With B-cyclodextrin

In this paper,the extraction of total flavonoids from Ginkgo Biloba Leaves are studied.In order to increase the solubility and Bioavailability of total flavonoids,the method of inclusion withβ-cyclodextrin(β-CD) for effective component extracted from Ginkgo Biloba Leaves is researched.The best process parameters obtained by extracting with ethanol and alkali is defined.By refering to the testing standard of normal Rutin and the indicator of ratio of total flavonoids,the researcher obtained the optimum extraction process of total G.Biloba flavonoids by alkali extracting is as follows:extracting solvent was pH.10,extracting temperature was 95℃,treatment time was 90min,acid-isolation value was 3.5,extracting for 2times.The extracting ratio of total flavonoids reached 85.40%.The optimum extraction process of the extraction of total G. Biloba flavonoids by ethanol extracting as follows:the extracting solvent was 60%ethanol solution,extracting temperature was 70℃,the proportion of G. Biloba to ethanol was 1:25,extracting time was 2.5h,the extracting ratio of total flavonoids reached 91.52%.Although the extracting ratio of ethanol extraction was a little larger than it of alkali extraction,considering the requirement for equipment and the consuming energy and the environmental pollution,the method of alkali extracting was more advanced than it of ethanol extracting.The researcher also have studied the optimized process for extracting material from G.Biloba included withβ-CD,and made a process comparison of the method of satured water solution to it of ultrasonic.The result showed that the optimum extracting process with satured water solution was as follows:including temperature was 45℃,the mass proportion ofβ-CD to GBE was 2:1,including time was 3h.The optimum extracting process for ultrasonic was following: including temperature was 45℃,the mass proportion ofβ-CD to GBE was 2:1, including time was 50min.By comparing single element of experiment,the result showed that there were a larger difference between the method of satured aqueous solution and ultrasonic inclusion,and every method had its own advantages and disadvantages.Through the experiment of GBE and GBE-β-CD on solubility,stability of high temperature and light stability,we find the solubility of GBE increased obviously with the inclusion ofβ-CD,with the inclusion ofβ-CD,thermal stability of total flavonoids improved obviously,anti-heating performance strengthen sharply,rate of degradation decreased evidently,and the light stability of including material increased obviously in comparison with GBE.