白蔹多酚超声波辅助酶法提取工艺优化及抗氧化、抑菌活性研究OA

The experiment aimed to optimize the ultrasonic-assisted enzymatic extraction process of Ampelopsis radix polyphenols(Arp)and study on its antioxidant and antibacterial activities.By conducting a single factor experiment to investigat the effects of liquid to material ratio,enzymatic hydrolysis temperature,ultrasound time,and enzyme addition on the extraction rate of Arp,and the extraction process was optimized by central composite design response surface method with Design Expert software.The scavenging capacities of the extraction on 1,1-diphenyl-2-trinitrophenylhydrazine(DPPH)radicals and 2,2-benzyl-bis-(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt(ABTS)radicals,and the antibacterial activity against Staphylococcus aureus and Escherichia coli were determined.The results showed that the optimum technological conditions were as follows:Liquid to material ratio of 33.00 mL/g,enzymolysis temperature of 45.00℃,ultrasonic time of 54.00 min and enzyme addition amount of 3.50%.Under these conditions,the extraction rate of Arp was 35.57%[relative standard deviation(RSD)=1.68%],with a deviation of 1.35%from the predicted value.The scavenging rates of DPPH radicals and ABTS radicals were 89.54%and 72.98%respectively,and the half maximal inhibitory concentration(IC50)value were 0.68 g/L and 0.86 g/L respectively.Arp exhibited good inhibitory effects against Staphylococcus aureus and Escherichia coli,with the minimum inhibitory concentration(MIC)of 3.125 000 g/L and 1.562 500 g/L,respectively.The study shows that ultrasonic-assisted enzymatic extraction process is simple,controllable,stable and feasible.The extracted Arp has strong antioxidant and antibacterial activities,and can be used as a feed additive in the livestock and poultry breeding industry.