The degradation of flavonol glycosides extracted from Ginkgo biloba was performed under different conditions and the degraded products were determined by reversed-phase high performance liquid chromatography （RP-HPLC...The degradation of flavonol glycosides extracted from Ginkgo biloba was performed under different conditions and the degraded products were determined by reversed-phase high performance liquid chromatography （RP-HPLC） method.Four stress conditions including acid（0.1 mol/L HCl）,base（0.1 mol/L NaOH）,temperature （70 ℃） and oxidation（0.03% H2O2,volume fraction） were used for the forced degradation studies.The pH stabilities of the flavonol glycosides were determined in phosphate buffers of varying pH values from 4.5 to 7.4.The degradation rate constants and half-life of three Ginkgo flavonol aglycones（quercetin,kaempferol and isorhamnetin） which represent Ginkgo flavonol glycosides were calculated in forced degradation and pH-stability studies of them.The resuits indicate that the three substances were more stable when incubated under acid condition and showed pH-dependent stability.The degradation was observed to follow first-order kinetics in all degradation studies.The stability results could provide important bases on development,preparation and storage of products of Ginkgo biloba extract and should be significantly considered during the further formulation development.展开更多
文摘The degradation of flavonol glycosides extracted from Ginkgo biloba was performed under different conditions and the degraded products were determined by reversed-phase high performance liquid chromatography （RP-HPLC） method.Four stress conditions including acid（0.1 mol/L HCl）,base（0.1 mol/L NaOH）,temperature （70 ℃） and oxidation（0.03% H2O2,volume fraction） were used for the forced degradation studies.The pH stabilities of the flavonol glycosides were determined in phosphate buffers of varying pH values from 4.5 to 7.4.The degradation rate constants and half-life of three Ginkgo flavonol aglycones（quercetin,kaempferol and isorhamnetin） which represent Ginkgo flavonol glycosides were calculated in forced degradation and pH-stability studies of them.The resuits indicate that the three substances were more stable when incubated under acid condition and showed pH-dependent stability.The degradation was observed to follow first-order kinetics in all degradation studies.The stability results could provide important bases on development,preparation and storage of products of Ginkgo biloba extract and should be significantly considered during the further formulation development.
