发酵红树莓汁乳酸菌的筛选及抗氧化活性研究

从抗氧化活性、胃肠道环境耐受性、抑菌性能及菌体生长能力四个方面选出优良乳酸菌株，并对菌株发酵红树莓（Rubus idaeus L.）汁进行研究。结果表明，从12株乳酸菌中筛选出了1株优良副干酪乳杆菌（Lactobacillus paracasei）YJ1，菌株YJ1发酵红树莓汁中总黄酮和总酚含量分别增加了23.00%、18.58%，与未发酵的红树莓原汁相比，发酵后的红树莓汁体外抗氧化活性极显著提高（P＜0.01），其DPPH和羟基自由基清除能力分别提高了22.92%、15.63%；2,2'-联氨-双-3-乙基苯并噻唑啉-6-磺酸（ABTS）和铁离子还原/抗氧化能力（FRAP）法测定的总抗氧化能力分别增加了36.31%、39.48%。

Screening of lactic acid bacteria and antioxidant activity of fermented red raspberry juice

The excellent lactic acid bacteria strains were selected based on the four aspects of antioxidant activity, gastrointestinal environment tolerance, antibacterial performance and bacterial growth ability, and the fermentation of the red raspberry (Rubus idaeus L.) juice was studied. The results showed that an excellent Lactobacillus paracasei YJ1 was screened from 12 strains of lactic acid bacteria. The contents of total flavonoids and total phenols in fermented red raspberry juice by strain YJ1 increased by 23.00% and 18.58%, respectively. Compared with the unfermented red raspberry juice, the antioxidant activity in vitro of fermented red raspberry juice was highly significantly improved (P＜0.01), the DPPH and hydroxyl free radical scavenging capacity increased by 22.92% and 15.63%, respectively, and the total antioxidant capacity determined by ABTS method and FRAP method increased by 36.31% and 39.48%, respectively.