Complex Enzymatic Extraction of Total Flavonoids from Pomegranate Fruitlets and Their Anti-α-Glucosidase Activity

To optimize the complex enzymatic(cellulose-pectinase-papain)extraction of total flavonoids from pomegranate fruitlets and to determine its anti-α-glucosidase activity.with the yield of total flavonoids as an evaluation index,D-optimal mixture design was applied to optimize the complex enzymeratio,and orthogonal experimental design was adopted in the optimization of solid/liquid ratio,medium pH,enzymatic hydrolysis temperature and enzymatic hydrolysis time based on the single factor test,then the anti-α-glucosidase activity was determined with PNPG as substrate. The results showed that optimal ratio of enzyme was determined to be 44.2% for cellulose,31.6% for pectinase and 24.2% for papain,to obtain a 3.38% of total flavonoids yield,the optimal conditions were determined to be 1:18 (g/mL)for solid/liquid ratio,5.0 for medium pH,50 ℃ for enzymatic hydrolysis temperature and 4.0 h for enzymatic hydrolysis time,the substrate inhibition rate reached 63.9% on α-glucosidase and the inhibitory effect of IC₅₀ was 1.059 mg/mL at the centration was 1.5 mg/mL.There was a dose-response relationship between the total flavonoids and anti-a-glucosidaseactivity in the range of 0.15~1.5 mg/mL of concentration,the inhibition mechanism was reversible inhibition and non competitive inhibition. This method can provide ascientific basis for the extraction and application of total flavonoids from pomegranate fruitlets.