【摘要】 为筛选出对肌肉蛋白水解能力较强的乳酸菌并探究其发酵特性，以内蒙古地区特色发酵食品中分离的乳酸菌为研究对象，利用透明圈及福林酚法筛选菌株，采用生理生化及耐受性试验评价筛选菌株的发酵特性，并进一步通过蛋白水解特性试验明确菌株对肌肉蛋白的水解能力。结果表明，透明圈直径较大且蛋白酶活力较高的两株菌为YR3-1和SMN-2，蛋白酶活力分别为23.13 U/m L和22.06 U/m L，经鉴定均为戊糖片球菌（Pediococcus pentosaceus）。两株菌均具有良好的耐酸（pH 3.5）、耐盐（6%NaCl）、耐温度（41℃）、耐胆盐（0.3%胆盐）和耐亚硝酸盐（150 mg/L NaNO₂）特性，菌株YR3-1耐受性优于菌株SMN-2，符合肉制品发酵剂菌株的要求，并且其均能抑制金黄色葡萄球菌和大肠埃希氏菌。菌株YR3-1和SMN-2使肌原纤维蛋白发酵体系中游离氨基酸态氮含量显著增加（P<0.05），十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）结果显示，两株菌均可有效促进肌原纤维蛋白中大分子物质水解。综上，菌株YR3-1具有较强降解肌肉蛋白的能力及良好的发酵特性，具有作为肉制品发酵剂开发潜力。更多还原

【Abstract】 In order to screen out lactic acid bacteria with strong muscle proteolytic ability and explore their fermentation characteristics, taking lactic acid bacteria isolated from characteristic fermented foods in Inner Mongolia as the research object, the strains were screened by transparent ring and folinphenol method, the fermentation characteristics of screened strains were evaluated by physiological, biochemical and tolerance tests, and the hydrolytic ability of the strain to muscle protein was further determined by proteolytic characteristic tests. The results showed that the two strains with larger transparent circle diameter and higher protease activity were YR3-1 and SMN-2, with protease activity of 23.13 U/ml and 22.06 U/ml, respectively. Both strains were identified as Pediococcus pentosaceus. Both strains had good acid resistance（pH 3.5）, salt resistance（6%NaCl）, temperature resistance（41 ℃）, bile salt resistance（0.3% bile salt） and nitrite resistance（150 mg/L Na NO₂）, the tolerance of strain YR3-1 was better than that of strain SMN-2, which met the requirements of meat product starter strains, and both could inhibit Staphylococcus aureus and Escherichia coli. Strains YR3-1 and SMN-2 significantly increased the contents of free amino nitrogen in the myofibrillar protein fermentation system（P<0.05）. The results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis（SDS-PAGE） showed that both strains could effectively promote the hydrolysis of macromolecular substances in myofibrillar protein. In conclusion, strain YR3-1 had strong ability to degrade muscle protein and good fermentation characteristics, and had the potential for development as a meat product starter culture.更多还原