具有保护肠上皮细胞HT-29免受大肠杆菌和H2O2损伤潜力的植物乳杆菌的筛选

益生菌可在肠道定植从而发挥抗炎或抗氧化活性，有利于宿主肠道健康。本实验研究了从新疆传统发酵乳制品中分离得到的8?株植物乳杆菌对大肠杆菌侵袭和过氧化氢刺激肠上皮细胞HT-29的保护作用。结果表明：在8?株植物乳杆菌中，植物乳杆菌35具有最高的黏附能力。植物乳杆菌35可通过取代、竞争、排阻的方式抑制大肠杆菌对HT-29细胞的黏附，抑制率分别为42.60%、59.17%、60.19%。植物乳杆菌35及其多糖可抑制大肠杆菌刺激HT-29细胞产生白细胞介素-8；同时保护HT-29细胞免受过氧化氢的损伤，增加超氧化物歧化酶、谷胱甘肽过氧化物酶活力水平并降低丙二醛含量。结论：植物乳杆菌35及其粗胞外多糖具有抑制大肠杆菌O157诱导的炎症性肠病的潜力。

Screening Lactobacillus plantarum Strains with Potential to Protect Human Intestinal Epithelium HT-29 Cells against Injury Caused by Escherichia coli or H2O2

Probiotic Lactobacillus strains can exert anti-inflammatory or antioxidant activities after colonization in the gut, which is beneficial for the host’s intestinal health. In this study, eight L. plantarum strains isolated from traditional fermented dairy foods in Xinjiang, China, were evaluated for their protective effects on HT-29 human intestinal epithelial cells against injury caused by Escherichia coli or hydrogen peroxide (H2O2). Among these strains, L. plantarum 35 showed the highest adhesion capacity to HT-29 cell monolayers, and it reduced E. coli adhesion to HT-29 cells by displacement, competition, and exclusion, with inhibition rates of 42.60%, 59.17%, and 60.19%, respectively. L. plantarum 35 and its crude exopolysaccharide (EPS) inhibited E. coli from stimulating HT-29 cells to produce interleukin-8 (IL-8), protected HT-29 cells against injury induced by H2O2, increased the levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and decreased malondialdehyde (MDA) content in HT-29 cells. Therefore, L. plantarum 35 and its crude EPS have the potential to inhibit inflammatory bowel disease induced by E. coli O157.