乳杆菌对致病性大肠杆菌K88和O138体外存活抑制的动力学研究

Kinetic Analysis of the Inhibition of in vitro Growth of Pathogenic Escherichia coli K88 and O138 by Lactobacillus Isolates from Porcine Intestine

摘要:

研究了一株分离自断奶仔猪小肠黏膜的肠乳杆菌L1(Lactobacillus intestinalis)体外发酵特性, 及其代谢产物对病原性大肠杆菌Escherichia coli K88和O138存活的影响。体外发酵结果表明：发酵12 h后, L1菌液pH值迅速降至3.90, 并产生大量乳酸, 为104.08 mmol/L。L1菌株代谢产物对K88和O138体外生长抑制的动力学研究表明：L1菌株代谢产物对K88和O138存活具有很强的抑制作用; L1菌株发酵液与含相同浓度乳酸的自制培养液比较结果表明：乳酸在L1菌株代谢物对K88和O138存活抑制中发挥了主要作用; K88和O138对pH 4.5的MRS培养液具有一定的耐受能力。

Abstract:

Fermentation property and kinetic analysis of the inhibition of in vitro growth of pathogenic Escherichia coli K88, O138 by Lactobacillus intestinalis isolated from porcine intestine mucus were investigated. The results of fermentation showed that L1 result in a pH of 3.90 within 12 h and a large amount of lactic acid production, with the concentration of 104.08 mmol/L. Kinetic analysis of the antibacterial activity of L1 metabolic product toward K88, O138 showed that CFUS display strong antibacterial activity toward K88, O138; the antibacterial activity of L1 CFUS was higher than the lactic acid control samples and was mainly due to the production of lactic acid; K88, O138 had the tolerance property toward pH 4.5.