抑制致病菌益生乳杆菌的胁迫耐受性及免疫活性

Simulated Gastrointestinal Stress Tolerance and Immunomodulatory Activity of Probiotic Lactobacillus with the Ability to Inhibit Pathogenic Bacteria

以16株乳杆菌为研究对象,分析其对病原菌金黄色葡萄球菌、鼠伤寒沙门氏菌及大肠杆菌的抑菌能力,黏附及干预病原菌黏附Caco-2细胞的作用,对酸及胆盐胁迫的抗逆性及对免疫细胞的调节活性。结果表明,植物乳杆菌KLDS 1.0328等乳杆菌的无细胞发酵上清液的抑菌圈直径均在15 mm以上。以鼠李糖乳杆菌LGG为对照,体外筛选出6株对Caco-2细胞体外黏附能力强或与之相当的菌株。基于竞争、排阻及置换试验,复筛出4株抑制病原菌和对Caco-2细胞黏附能力较强的乳杆菌,其中植物乳杆菌KLDS 1.0328竞争性抑制鼠伤寒沙门氏菌的抑制率为(72.52±4.94)%。此外,证实植物乳杆菌KLDS 1.0328对酸及胆盐的耐受性较强,对免疫细胞活性有较好的调节作用,具有在食品工业开发、应用的潜力。

In this study,16 strains of Lactobacillus were analyzed for their antibacterial ability against pathogenic bacteria Staphylococcus aureus,Salmonella typhimurium and Escherichia coli,adhesion and intervention of pathogenic bacteria to Caco-2 cells,resistance to acid and bile salt stress and regulatory activity to immune cells.The results showed that the diameter of inhibition zone corresponding to the cell-free supernatant of L.plantarum KLDS 1.0328 was more than 15 mm.Using Lactobacillus rhamnosus LGG as control,six Lactobacillus strains with stronger or equivalent adhesion ability to Caco-2 cells in vitro were screened.Four strains with strong inhibitory ability to Caco-2 cells were further screened based on the competition,exclusion and displacement tests.The inhibition rates of L.plantarum KLDS 1.0328 for competition of S.typhimurium was(72.52±4.94)%.Additionally,it is confirmed that L.plantarum KLDS 1.0328 has strong tolerance to acids and bile salts,has a good regulatory effect on immune cell activity,and has the potential for further development and application in food industry.