Optimization of extraction technology,evaluation of hypoglycemic activity and component analysis of total flavonoids from Hypericum japonicum
OBJECTIVE To optimize the ultrasound-assisted extraction-deep eutectic solvents technology of total flavonoids from Hypericum japonicum,evaluate its hypoglycemic activity in vitro,and analyze its chemical compositions preliminarily.METHODS The most suitable deep eutectic solvent for total flavonoids from H.japonicum was screened using the composition of hydrogen bond acceptor and donor,molar ratio,water content as factors,and the total flavonoid yield as the response value.Using liquid-solid ratio,ultrasonic power,ultrasonic temperature and ultrasonic time as factors,the yield of total flavonoids as response value,the extraction technology of total flavonoids from H.japonicum was optimized by single-factor experiments combined with Box-Behnken response surface method,and the optimum extraction technology was validated.Taking acarbose as the positive control,the inhibitory activities of total flavonoids from H.japonicum on α-amylase and α-glucosidase in vitro were determined.The chemical constituents of total flavonoids from H.japonicum were analyzed by UPLC combined with comparing the reference substances.RESULTS The most suitable deep eutectic solvent was choline chloride-oxalic acid(the molar ratio of 1∶1,the water content of 30%).The optimum extraction technology was as follows:the ratio of liquid-solid was 52∶1(mL/g),the ultrasonic temperature was 54℃,the ultrasonic power was 240 W,and the ultrasonic time was 42 min;the total extraction yield of total flavonoids from H.japonicum in 3 validation tests was(73.26±2.48)mg/g,the relative error of which with the theoretical value(73.48 mg/g)was-0.30%.The total flavonoids from H.japonicum could inhibit α-amylase and α-glucosidase with IC50 values of 0.73 and 0.44 mg/mL,respectively,which were higher than those of acarbose(0.23 and 0.15 mg/mL).UPLC analysis showed that the total flavonoids from H.japonicum contained isoquercetin,quercitrin,quercetin-7-O-α-L-rhamnoside and quercetin.CONCLUSIONS The optimized extraction technology of total flavonoids from H.japonicum is stable and feasible,and the extract has certain hypoglycemic activity in vitro and contains isoquercetin,quercitrin and quercetin-7-O-α-L-rhamnoside,etc.
total flavonoids from Hypericum japonicumultrasound-assisted extractiondeep eutectic solventsresponse surface methodhypoglycemic activitycomponent analysis
国家科技期刊平台
NSTL
万方数据
