本研究对一位128岁老人源罗伊氏乳杆菌进行了体外益生特性和安全性分析。采用模拟胃肠液对49株罗伊氏乳杆菌进行耐受筛选，得到了3株存活率都大于90.00%的菌株，分别是LT018、LT037、LT046。对上述3株罗伊氏乳杆菌进行表面特性、抑菌活性和安全性分析，结果表明，LT018具有较好的粘附繁殖能力（疏水性为54.65%，凝集性为67.20%），菌株的表面疏水性和凝集性之间存在负相关（R = -0.869）；非酸性抑菌活性物质在酸性条件下才发挥作用，它们的上清液对大肠埃希氏菌、金黄色葡萄球菌、蜡样芽胞杆菌、伤寒沙门氏菌和福氏志贺氏菌均有较明显的抑制作用，其中对金黄色葡萄球菌的抑制效果最佳，抑菌圈直径均大于15.00 mm；它们都不具有产生物胺有害物质的活性，除氯霉素外，对其他4种临床常用抗生素（红霉素、四环素、庆大霉素、万古霉素）敏感。综合上述结果，认为这些菌株具有良好的开发潜力。

The safety and in vitro probiotic properties of Lactobacillus reuteri isolated from a 128-year-old woman were analyzed in this study. Forty-nine strains of Lactobacillus reuteri were screened for their tolerance to simulated gastrointestinal fluid, and three strains with a survival rate of more than 90.00% were obtained: LT018, LT037, and LT046. The analyses of surface characteristics, antimicrobial activity, and safety of these three Lactobacillus reuteri strains were investigated, and the results showed that LT018 had relatively good adhesive reproductive capacity (hydrophobicity: 54.65% and auto-aggregation: 67.20%), and the surface hydrophobicity was negatively correlated with agglutination of the strains (R = -0.869). The non-acidic antibacterial substances could exert antibacterial action under acidic conditions, and the supernatant of these three strains had obvious inhibitory effects against Escherichia coli, Staphylococcus aureus, Bacillus cereus, Salmonella typhi, and Shigella flexneri. In particular, the strongest inhibitory effect against Staphylococcus aureus was observed, with an inhibition zone diameter of more than 15.00 mm. The strains did not produce harmful biogenic amines, and were sensitive to four types of commonly used antibiotics (erythromycin, tetracycline, gentamicin, and vancomycin), but were resistant to chloramphenicol. Based on the above results, these strains are believed to have a good potential for development.

国家自然科学基金资助项目（31371762）；乳业生物技术国家重点实验室开放基金项目（SKLDB2013-07）