Optimization of extraction technology of flavonoids from howthorn leaves by response surface method

Response surface method was used to optimize the technological conditions of extracting flavonoids compounds from howthorn leaves,with extraction yield of flavonoids as indicator and ethanol reflux as extraction method.Single factor experiment and response surface method were used to discuss the influence on extraction yield by extraction temperature,liquid-solid ratio,the ethanol concentration and extraction time.The regression equation prediction model was developed by BoxBehnken center combination design and response surface method.The best extract conditions are as follows:the liquid-solid ratio 29mL/g,ethanol concentration 68%,extracting temperature 64℃ and extracting time 34min.Under the condition,the extraction yield of flavonoids is 3.07%.The results are agreed with model predictions.Thus the technology can be used as the extraction process of flavonoids from howthorn leaves.