Optimization on Extraction Conditions of Flavonoids from Cactus Using Response Surface Methodology

[Objective] The aim was to study the maximum extraction conditions of flavonoids from cactus by ethanol. [Method] With dried cactus powder as material and ethanol as solvent, by using response surface methodology, the effects of ethanol concentration, extracting temperature, extracting time and ratio of material to solvent were studied, and then the regression model was established to study the extracting condition. [Result] The result of fractional factorial design indicated that ethanol concentration and ratio of material to solvent played important roles in flavonoids extracting. The regression model of extraction rate(Y) to ethanol concentration(A) and ratio of material to solvent(B) was Y=-13.587 2+0.296 1 A+0.120 3 B-0.001 74 A2-0.003 0 B2(R2 =0.948), and the optimum conditions were 89% ethanol, ratio of solvent to material 21∶1, time 1 h, and temperature 55 ℃. The maximum extraction rate predicted by the model was 0.860%. [Conclusion] Response surface methodology was a good method for optimizing extraction conditions of flavonoids.