Influence of hydrolysis time on Ginkgo biloba flavonoids content / 中成药

ABSTRACT

AIM: To select proper hydrolysis time to determine Ginkgo biloba flavonoids content. METHODS: Sample dissolved in 25mL MeOH-25%∶HCl(4∶1) mixture and was heated to hydrolyze for various time, then diluted. Flavonoids'content was determined by HPLC. The conditions were developed by Shimpack CLC-ODS(150mm?6mm) column using 0.4% phosphoric acid solution-Methanol(50∶50), the detective wavelength was at 360nm with quercetin、kaempferol and isorhamnetin as standards, temperature being 30℃. RESULTS: Contents of flavonoids of Ginkgo biloba leaves,Ginkgo biloba crude extracts and Ginkgo biloba refined extracts were highest in the hydrolysis time of 2.0h. Ginkgo biloba flavonoids can be completely hydrolyzed in 2.0h. CONCLUSION: The hydrolysis time of 2.0h is best.