源自新疆赛里木酸奶的瑞士乳杆菌MB2-1荚膜多糖提取及其抗氧化活性

Extraction and Antioxidant Activity in vitro of Capsular Polysaccharide from Lactobacillus helveticus MB2-1 in Sayram Yogurt from Xinjiang

对分离自新疆赛里木传统拉丝酸奶的一株高产黏瑞士乳杆菌MB2-1(Lactobacillus helveticus MB2-1)荚膜多糖提取条件及其体外抗氧化效果进行研究。结果表明:选用胃蛋白酶和胰蛋白酶复合酶处理,在37℃、pH 6.0、酶用量为1400U/mL条件下水解18h,荚膜多糖产量达184.58mg/L。得到的荚膜多糖提取物中多糖含量为95.58%,蛋白质含量为1.82%。4.0mg/mL L.helveticus MB2-1荚膜多糖对DPPH自由基和.OH具有较强的清除效果,清除率分别达84.30%和48.22%以上,同时还具有较强的还原能力(83.88%)和Fe2+螯合能力(35.68%)。

The purpose of this work was to study extraction conditions and antioxidant activity in vitro of capsular polysaccharide（CP） from Lactobacillus helveticus MB2-1,a potent CP producing strain isolated from Sayram traditional yogurt from Xinjiang.After 18 h of hydrolysis with both pepsin and trypsin at a total dosage of 1400 U/mL under the conditions of 37 ℃ and pH 6.0,the yield of CP was 184.58 mg/L and the resulting extract contained 95.58% polysaccharide and 1.82% protein.At 4.0 mg/mL,it had strong scavenging activities against DPPH and hydroxyl free radicals with corresponding scavenging rates of 84.30% and 48.22% and powerful reducing power（83.88%） and ferrous ion-chelating capacity（35.68%）.