抗幽门螺杆菌乳酸菌的筛选

通过测定干酪乳杆菌（Lactobacillus casei）的自凝聚、疏水性及抑菌实验来筛选粘附性高、对幽门螺杆菌（Helicobacter pylori）有强抑制作用的益生菌株，并通过干酪乳杆菌与幽门螺杆菌的交互凝集和对幽门螺杆菌尿素酶活性的抑制进一步探讨其抑菌机制。结果表明，在4株干酪乳杆菌中，菌株JY300-8的自凝聚百分比在24 h达到71.7%，比菌株JY、JY160-15、JY300-10分别高19.7%、28.8%、29.6%（P＜0.05）；疏水性百分比为72.3%，比菌株JY、JY160-15、JY300-10分别高4.1%、8.0%、7.5%（P＜0.05）。同时，菌株JY300-8在24 h时的共凝集百分比为64.4%，较菌株JY提高了5.3%；而且菌株JY300-8对幽门螺杆菌尿素酶活性的抑制率达到62.3%。结果表明，在4株干酪乳杆菌中，菌株JY300-8具有良好的益生性能，对胃癌的生物致病菌具有良好的抑制效果，可用于后续胃癌动物模型的研究和抗胃癌的益生菌制剂的开发。

Screening of lactic acid bacteria against Helicobecter pylori

The probiotic strains with high adhesion and strong inhibitory effect on Helicobacter pylori were screened by determining the self-aggregation, hydrophobicity and bacteriostasis of Lactobacillus casei, and the antibacterial mechanism of L. casei was further explored through the co-aggregation of L. casei and H. pylori and the inhibition of urease activity of H. pylori. The results showed that among the four strains of L. casei, the self-aggregation percentage of the strain JY300-8 was 71.7% at 24 h, which was 19.7%, 28.8% and 29.6% higher than the strain JY, JY160-15 and JY300-10, respectively (P＜0.05); the hydrophobicity percentage was 72.3%, which was 4.1%, 8.0% and 7.5% higher than the strain JY, JY160-15 and JY300-10, respectively (P＜0.05). At the same time, the co-aggregation percentage of the strain JY300-8 was 64.4% at 24 h, which was 5.3% higher than that of the strain JY. Moreover, the inhibition rate of the strain JY300-8 on the urease activity of H. pylori was 62.3%. The results showed that the strain JY300-8 had good probiotic activity among the four strains of L. casei, and had good inhibitory effect on the biological pathogens of gastric cancer, which could be used for the follow-up study of animal models of gastric cancer and the development of probiotic preparations against gastric cancer.