AUTHOR=Zhang Hua , HuangFu HePing , Wang Xing , Zhao ShanShan , Liu Yuan , Lv Haoxin , Qin GuangYong , Tan Zhongfang 

TITLE=Antibacterial Activity of Lactic Acid Producing Leuconostoc mesenteroides QZ1178 Against Pathogenic Gallibacterium anatis

JOURNAL=Frontiers in Veterinary Science

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2021.630294

DOI=10.3389/fvets.2021.630294

ISSN=2297-1769

ABSTRACT=<p>Lactic acid bacteria (LAB) convert carbohydrates into organic acids [mainly lactic acid (LA)], which reportedly have bactericidal activities. <italic>Gallibacterium anatis</italic> is a Gram-negative bacteria which infects birds, and causes significant economic losses. In this study, we investigated the antibacterial activity of the LA producing, <italic>Leuconostoc mesenteroides</italic> QZ1178 from Qula (fermented food), against <italic>G. anatis</italic>, using the Oxford cup method. Our data showed that <italic>L. mesenteroides</italic> QZ1178 inhibited <italic>G. anatis</italic> isolates from different origins; however, <italic>L. mesenteroides</italic> QZ1178 antibacterial activity dropped dramatically at pH 5.5–pH 6. The LA concentration and pH of the liquid broth containing <italic>L. mesenteroides</italic> QZ1178 after 24 h culture was 29 mg/mL and 3.6, respectively. This concentration (29 mg/mL at pH 3.6) and the antibiotic, cefotaxime (minimum inhibitory concentration (MIC) 2.5 μg/mL) effectively inhibited <italic>G. anatis</italic> (GAC026) growth as observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). <italic>Gallibacterium anatis</italic> treated with LA exhibited extensive cell surface collapse, increased cell damage, cell membrane disruption, and cytoplasmic leakage, indicative of cell lysis. We suggest <italic>L. mesenteroides</italic> QZ1178 exerts potential antibacterial effects against the poultry pathogen, <italic>G. anatis</italic> via LA.</p>