中文摘要：

目的：比较单一和混合乳酸菌对3种肠道病原菌的抑菌作用,并对其体外抑菌机制进行初步探讨。方法：测定菌株L.fermentum Xn、L.rhamnosus J、L.plantarum Yd、L.plantarum La的单一以及混合菌株的发酵特性,再比较以上4株菌单一和混合乳酸菌发酵对3种肠道病原菌的抑菌作用及体外抑菌机制。结果：混合乳酸菌在发酵10 h后的酸度为120.07°T,高于4种单菌株发酵。乳酸菌混合发酵后,除了对大肠杆菌的抑菌圈直径大小仅次于菌株L.plantarum La外,对沙门氏菌和艰难梭菌的抑菌圈直径均大于4种单菌株。结论：4种单菌株短时间内发酵对肠道病原菌抑制作用的影响主要是乳酸菌在生长过程中产生的酸。混合乳酸菌发酵对肠道病原菌的抑制作用较强于单菌株发酵,这与混合乳酸菌短时间内发酵酸度上升比单菌株发酵快有关。

英文摘要：

Objective： We compared the inhibitory effects of single and mixed lactic acid bacteria on 3 kinds of pathogenic bacteria, and to explore the mechanism of antibacterial activity in vitro. Methods： L. fermentum Xn, L. rhamnosus J, L. plantarum Yd, L. plantarum La single and mixed strains fermentation characteristics were determined, and then to compare the above 4 strains of single and mixed fermentation of lactic acid bacteria on bacteriostasis and antibacterial mechanism of 3 kinds of intestinal pathogenic bacteria. Results： After fermentation for 10 h, the acidity of mixed lactic acid bacteria was 120.07 °T, and the acidity of mixed lactic acid bacteria was higher than that of the single strain fermentation of 4 strains. After the mixed fermentation of lactic acid bacteria, in addition to the size of the bacteriostatic circle diameter of Escherichia coli was only inferior to that of strain L. plantarum La, the diameter of the inhibition circle of Salmonella and Clostridium difficile was greater than that of the 4 strains. Conclusion： The fermentation characteristics of four strains would be better. Lactic acid bacteria could produce organic acid in the metabolic process, which was the main factors of inhibiting the intestinal pathogens in vitro. The inhibitory effect of the mixed bacteria on the intestinal pathogens was better than the four strains.