ABSTRACT
AIM:To put forward three-level design(Box-Behnken design)for fitting response surfaces to optimize the extraction technology of total flavonoids from Hypericum ascyron L.METHODS:Four factors,including temperature,reflux time,concentration of ethanol,ratio of solvent to raw material were used to examine the yield of total flavonoids.Prediction was carried out through comparing the observed and predicted values.RESULTS:The results suggested that ethanol concentration and extraction temperature were two statistically significant factors.The optimum conditions of extraction process consisted of the ratio(mL:g)of solvent to material(13.3:1),ethanol concentration(53.2%),extraction temperature(78.7℃)and extraction time(2.3h).Regression coefficient of binomial fitting complex model was as high as 0.984 6.Bias between observed and predicted values was-4.01%.CONCLUSION:Box-Behnken design is success in optimizing the extaction in close agreement with the predicted values of the mathematic model.
ABSTRACT
AIM:To put forward three-level design(Box-Behnken design) for fitting response surfaces to optimize the extraction technology of total flavonoids from Hypericum ascyron L.METHODS:Four factors,including temperature,reflux time,concentration of ethanol,ratio of solvent to raw material were used to examine the yield of total flavonoids.Prediction was carried out through comparing the observed and predicted values.RESULTS:The results suggested that ethanol concentration and extraction temperature were two statistically significant factors.The optimum conditions of extraction process consisted of the ratio(mL:g)of solvent to material(13.3:1),ethanol concentration(53.2%),extraction temperature(78.7℃)and extraction time(2.3h).Regression coefficient of bino-mial fitting complex model was as high as 0.984 6.Bias between observed and predicted values was -4.01%.CONCLUSION:Box-Behnken design is success in optimizing the extaction in close agreement with the predicted values of the mathematic model.