Optimiazation of Extracting Technology of Yam Bean Polyphenols and Comparison of Different Determination Methods

The optimal extracting technology of yam bean polyphenols was studied by the fractional factorial design, as well as two kinds of determination methods were compared. The results were as following: When the FC was used, the optimal extracting conditions were ethanol concentration 75.3%, ratio of the ethanol to HCl 98.3:1.7, temperature 82.5 ℃, and ratio of material to solvent 1:30. Under these conditions the highest extracting rate was 11.1615 mg/g. When the Prussian blue was used, the optimal extracting conditions were ethanol concentration 70%, ratio of ethanol to HCl 97.6:2.4, temperature 96 ℃, ratio of material to solvent 1:30. Under these conditions the highest extracting rate was 4.4503 mg/g.