东北地区传统发酵食品中两株植物乳杆菌的安全性评价

针对已分离的植物乳杆菌L12和L20通过体外和体内两种方法进行安全性评价。通过体外实验测定乳酸水解活性抗生素敏感性，胆盐水解酶活性，D-乳酸含量，γ溶血等指标；体内实验是对小鼠进行短期口服毒性的研究，口服0.2 mL（109 CFU/mL）的实验性细菌溶液30 d。结果表明，体外实验中，两株菌株均具有良好的抗氧化活性，对抗生素敏感性高，胆盐水解酶活性高，D-乳酸含量低，γ溶血；体内实验中灌胃给药对治疗小鼠的生长、行为、摄食量、器官重量或组织病理学分析均无不良影响。与对照组相比，益生菌组小鼠血清MDA浓度和肝脏GSH含量差异有统计学意义(P<0.05)。这些结果表明，菌株L12和L20是非致病性的，人直接食用是安全的。

Safety Assessment of Two New Lactobacillus Plantarum Strains Isolated from Traditional Fermented Food of Northeast China

This study aimed to evaluate the safety of previously isolated Lactobacillus strains (L. Plantarum L12 and L20) by in vitro and in vivo methods. Antibiotic sensitivity, bile salt hydrolysis activity, D-lactic acid content, and hemolytic activity were analyzed in vitro. Then, a short-term oral toxicity study was conducted in mice, which received 0.2 mL (109 CFU/mL) of experimental bacterial solutions orally for 30 days. The results showed that both strains had good antioxidant activity, high sensitivity to antibiotics, high bile salt hydrolase activity, low D-lactic acid content, and gamma hemolysis. Intragastric administration had no adverse effects on growth, behavior, food intake, organ weight, or histopathological analysis of the treated mice. Compared with control mice, the serum malondialdehyde concentration and liver glutathione content of probiotic-treated mice were statistically different (P<0.05). These results suggest that strains L12 and L20 are nonpathogenic and likely to be safe for human consumption.