该研究旨在利用野生型秀丽隐杆线虫N2对一款富含大豆异黄酮苷元的大豆酸奶进行生物活性评价。采用高效液相色谱法对该大豆酸奶中大豆苷元、黄豆黄素和染料木素的含量进行分析表明，结果表明其苷元含量比未发酵豆乳增加了26.4倍。采用体外抗氧化实验和野生型秀丽隐杆线虫N2对大豆酸奶的抗氧化活性进行评价，发现发酵后的混合豆乳对DPPH自由基、超氧自由基、ABTS+自由基的清除率分别为98.03%、73.77%、83.37%，比发酵前显著提高（P<0.05）。大豆酸奶样液可将秀丽隐杆线虫的平均寿命和最大寿命分别延长21.57%和22.58%；饲喂大豆酸奶样液后，线虫体内超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性显著增强，体内活性氧（ROS）水平显著下降（P<0.05），线虫抗应激能力显著增加（P<0.05）。说明通过乳酸菌发酵制备高苷元含量的大豆酸奶，可有效提高产品抗氧化活性，并能延长秀丽隐杆线虫寿命。

The bioactivity of a soybean yogurt rich in soybean isoflavone aglyconesusing wild-type C. elegans N2 was evaluated. The contents of daidzein, glycitein and genistein in the soybean yoghurt were analyzed by HPLC. The results showed that the total aglyconecontent of the soy yogurt was 26.4 times higher than that of unfermented soy milk. The antioxidant activity of soybean yogurt was evaluated by in vitro antioxidant test and experiments with wild-type C. elegans N2. It was found that the scavenging rates for the DPPH free radicals, superoxide free radicals and ABTS+ free radicals of the soybean yogurt were 98.03%, 73.77% and 83.37%, respectively, which were significantly higher than that before fermentation (P<0.05). Furthermore, after intervention with the supernatant of soybean yogurt, the average lifespan and maximum lifespan of C. elegans were prolonged by 21.57% and 22.58%, respectively, the superoxide dismutase (SOD) activity and catalase (CAT) activity increased significantly (P<0.05), the level of reactive oxygen species (ROS) in the body decreased significantly (P<0.05), and the anti-stress ability of C. elegans increased significantly (P<0.05). Theresults showed that the soybean yoghurt high in aglycone content prepared through lactic acid bacteria fermentation could effectively improve the antioxidant activity of the product and prolonged the lifespan of C. elegans.

国家自然科学基金项目（31871790；31771940）；广东省重点领域研发计划项目（2018B020205002）