Optimization of Ultrasonic-assisted Extraction of Total Flavonoids from Mulberry Leaves Using Response Surface Methodology

In order to extract total flavonoids from mulberry leaves efficiently,ultrasonic-assisted extraction was optimized using response surface methodology.Based on single factor experiments,a three factor three level central composite design was carried out to establish a quadratic regression model for the extraction efficiency of mulberry leaf total flavonoids as a function of extraction time,ethanol volume fraction and material mass concentration.The optimum extraction conditions were obtained as follows: extraction temperature 50 ℃,ethanol volume fraction 80%,material mass concentration 0.025 g/mL,and extraction time 40 min.Under these conditions,the predicted extraction efficiency of mulberry leaf total flavonoids was 1.60%,and the experimental value was 1.59%.The result indicated that the established model well predicted the extraction efficiency of total flavonoids from mulberry leaves and the optimized extraction conditions are a good reference for practice.