Open AccessScreening beneficial bacteriostatic lactic acid bacteria in the intestine and studies of bacteriostatic substances
Author(s) -
Zhijing Liu,
Cong Xu,
Ruijun Tian,
Wan Wang,
Jiage Ma,
Liya Gu,
Fei Liu,
Zhanmei Jiang
Publication year - 2021
Publication title -
journal of zhejiang university. science b
Language(s) - English
Resource type - Journals
eISSN - 1862-1783
pISSN - 1673-1581
DOI - 10.1631/jzus.b2000602
Subject(s) - probiotic , lactobacillus salivarius , microbiology and biotechnology , lactobacillus paracasei , human gastrointestinal tract , biology , bacteria , pathogenic bacteria , antibacterial activity , lactobacillus , lactic acid , population , fermentation , food science , medicine , genetics , environmental health
Lactic acid bacteria (LAB) are a representative probiotic. As the dominant flora in the human intestinal tract, LAB can regulate the balance of human intestinal flora and improve host health. The purpose of this study was to isolate and screen LAB that are well suited to the intestinal characteristics of the Chinese population, with excellent probiotics and high antibacterial activity. After 16S ribosomal RNA (rRNA) homology and phylogenetic tree analysis, potential probiotics were tested for their antibacterial activity, resistance to artificial gastrointestinal fluid and drugs, surface hydrophobicity, and safety. Three strains of LAB with acid resistance, bile salt resistance, epithelial cell adhesion, and no multidrug resistance were selected: Lactobacillus salivarius , Leuconostoc lactis , and Lactobacillus paracasei . Analysis of the antibacterial active substances in the three strains and their fermentation broths revealed that the main antibacterial substances of L. lactis were organic acids, whereas those of L. salivarius and L. paracasei were organic acids and bacteriocins with broad-spectrum antibacterial activity. These three strains of probiotic LAB with high antibacterial activity were identified as bacterial resources that could potentially be used to develop probiotic preparations for the prevention and treatment of intestinal diseases caused by intestinal pathogens.