采用牛津杯双层平板法筛选得到2株具有抑菌能力的乳酸菌——乳酸片球菌CCFM 28和格氏乳杆菌JCM 11657。排除有机酸作用后，发酵上清液经过氧化氢酶与蛋白酶处理后仍具有抑菌能力，表明这2株菌的抑菌物质主要为细菌素，且实验结果表明CCFM 28的抑菌谱较JCM 11657更广泛。通过测定代时以及耐酸耐胆盐能力，从多株不产细菌素的乳酸片球菌和格氏乳杆菌中获得与CCFM 28和JCM 11657生物学性质最为接近的乳酸片球菌ZT-45与格氏乳杆菌JS-SZ-1-5。以5周龄C57BL/6雄性小鼠作为实验对象，研究2对产与不产细菌素的乳酸菌对宿主肠道菌群结构及代谢产物的影响。实验结果表明，乳酸菌是否产细菌素、所产细菌素的种类和/或抑菌谱的大小均可能会影响小鼠肠道菌群结构，但不影响短链脂肪酸含量的变化。

In this paper, two lactic acid bacteria, Pediococcus acidilactici CCFM 28 and Lactobacillus gasseri JCM 11657, which show antimicrobial activity independent of pH value were obtained through agar well diffusion test. With treatment of catalase and protease, the neutral supernatant of these two strains still exhibit strong antimicrobial activities. Thus, the antimicrobial substances in the supernatant were mainly bacteriocins. Besides, the inhibition spectrum of CCFM 28 was larger than that of JCM 11657. Furthermore, another two lactic acid bacteria without bacteriacin, P. acidilactici ZT-45 and L. gasseri JS-SZ-1-5, with similar biological properties with CCFM 28 and JCM 11657 such as generation time, ability of resistance to acid and bile salts, were screened as negative control strains for the bacteriocin-producing strains to treat 5-week-old C57BL/6 male mice together with CCFM 28 and JCM 11657. Results from animal experiment suggested that producing bacteriocin or not, the type of bacteriocin or the range of inhibition spectrum all might affect the composition of gut microbiota, but not affect the levels of short chain fatty acids in gut.