植物乳杆菌Y42无细胞培养上清抑制单增李斯特菌生物膜形成研究

为研究植物乳杆菌Y42无细胞培养上清对单核细胞增生李斯特菌(LM)生物膜形成的抑制作用,采用微孔酶标板刃天青显色法确定Y42上清的最小抑菌质量浓度(MIC),微孔酶标板结晶紫染色法检测Y42上清对LM生物膜形成的影响,软琼脂法测定Y42上清对LM爬行运动性的影响。结果显示Y42上清最小抑菌质量浓度为60mg/mL；当Y42上清作用质量浓度为MIC的1/32、1/16、 1/8、 1/4、 1/2时,LM的运动圈直径由81.15mm减小为78.31、 75.35、 69.51、 54.91、33.09mm,对LM生物膜形成的抑制率达到32.90%、 30.81%、 40.75%、 39.93% 、12.15%；普通光学显微镜在10×40倍放大倍数下,观察到Y42上清可显著减少LM在盖玻片上形成生物膜的量。Y42无细胞培养上清可通过抑制LM的运行性来抑制其生物膜的形成。

Effects of Lactobacillus plantarum Y42 Cell-Free Culture Supernatant on Listeria monocytogenes Biofilm Formation

In this study, the effect of cell-free aulture supernatant of Lactobacillus plantarum-Y42 on the biofilm formation of Listeria monocytogenes (LM) was assessed. Minimum inhibitory concentration (MIC) of L. plantarum-Y42 cell-free culture supernatant against planktonic LM was determined using the Resazurin staining method. Then the effect of sub-MICs of L. plantarum-Y42 cell-free culture supernatant on the swarming motility and biofilm formation of LM were tested. MIC of L. plantarum-Y42 cell-free culture supernatant against LM was 60mg/mL. When LM was exposed to L. plantarum-Y42 cell-free culture supernatant at the sub-MICs of 0,1/32,1/16,1/8,1/4,1/2MIC, respectively, the corresponding swarming diameters of LM were 81.15,8.31,5.35,9.51,4.91, and 33.09mm, respectively. The inhibition rates of biofilm formation were 0,2.90%, 30.81%, 40.75%, 39.93%, and 12.15%, respectively. Sub-MICs of L. plantarum-Y42 supernatant did not inhibit the normal growth and proliferation of LM, but significantly inhibited the biofilm formation of LM.