【摘要】 文章旨在筛选分离得到具有高产胞外多糖(Exopolysaccharide,EPS)性能的乳酸菌。以新鲜水果及醪糟为研究对象，通过涂布、三区划线分离筛选，从人参果中得到一株高产EPS的乳酸菌菌株RSG7，其EPS产量为47.384 g/L。对其进行形态学、16S rDNA测序以及同源性分析，结果显示该菌株为Leuconostoc mesenteroides，并命名为Leu. mesenteroides RSG7。生物学特性分析表明，Leu. mesenteroides RSG7菌株能利用蔗糖、乳糖、麦芽糖、赤藓糖醇、山梨醇、D-果糖、D-核糖、D-甘露糖、D-木糖、海藻糖、D-棉子糖、D-半乳糖、L-阿拉伯糖、鼠李糖和水苏糖，生长的最佳时间是13 h，最适pH值为7.0～8.0,NaCl、尿素、胆盐等耐受性分别为0%～4%、0%～2%和0%～0.05%。这些良好的特性可为新型优质益生菌资源的开发及乳酸菌EPS商业化的应用提供理论基础。更多还原

【Abstract】 In order to screen and isolate lactic acid bacteria(LAB) with high yield of exopolysaccharides(EPS), fresh fruit and fermented glutinous rice were selected as the research object. One LAB strain,dubbed RSG7, was isolated from pepino(Solanum muricatum Aiton) by spread-and steak-plate methods,its EPS yield was 47.384 g/L. According to morphological, 16S rDNA sequencing and homology analyses, this strain was identified as Leuconostoc mesenteroides and finally named Leu. mesenteroides RSG7. Biological characterization showed that Leu. mesenteroides RSG7 strain could utilize sucrose,lactose, maltose, erythritol, sorbitol, D-fructose, D-ribose, D-mannose, D-xylose, trehalose, D-raffinose,D-galactose, L-arabinose, rhamnose and stachyose. The optimal growth time and pH value were 13 h and 7.0–8.0, respectively. The tolerance of NaCl, urea, bile salt was 0%–4%, 0%–2% and 0%–0.05%,respectively. These excellent characteristics provide theoretical basis for the development of new highquality probiotic resources and the commercialization of LAB EPS.更多还原