Inhibitory effect of lactic acid bacteria isolated from kimchi against murine norovirus.

Human norovirus causes gastroenteritis through a fecal-oral route. However, there are no effective therapeutic agents owing to the lack of culture systems. Alternatively, antiviral food extracts and beneficial microorganisms could be developed as antiviral agents. Here, we investigated the inhibitory effects of 142 lactic acid bacteria (LAB) or LAB-free filtrate from kimchi products against murine norovirus-1 (MNV-1) in RAW264.7 cells. LAB strains were identified through 16S rRNA gene sequencing. Cells were pre-treated with LAB or LAB-free filtrate, and co-treated with LAB and MNV-1 at 5 °C for 21 days. Among the 56 coccus-shaped LAB, pre-treatment of Pediococcus pentosaceus (CAU170229-2 and CAU170230-3) and Weissella cibaria (CAU170231-1 and CAU170231-3) significantly reduced MNV-1 by 1.93 ± 0.21–3.49 ± 0.43 to log 10 PFU/mL. Among the 86 rod-shaped LAB, pre-treatment of Lactobacillus sakei (CAU170208-2 and CAU170210-4) and Lactobacillus curvatus (CAU170210-2 and CAU170235-3) significantly decreased MNV-1 by 1.42 ± 0.26–1.70 ± 0.63 log 10 PFU/mL. LAB-free filtrates decreased MNV-1 by 0.26 ± 0.07–0.50 ± 0.18 to log 10 PFU/mL, and MNV-1 co-treated with LAB slightly reduced MNV-1 by 0.56 ± 0.07–0.60 ± 0.09 to log 10 PFU/mL. Thus, W. cibaria , P. pentosaceus, L. curvatus, and L. sakei from kimchi are promising anti-noroviral candidates. • In total, 481 lactic acid bacteria (LAB) were isolated from 42 kimchi products. • LAB pre-treatment and co-treatment inhibited murine norovirus-1 (MNV-1). • LAB-free filtrates slightly inhibited MNV-1. • MNV-1 was significantly reduced by pre-treatment of W. cibaria and P. pentosaceus. • LAB isolated from kimchi are promising anti-noroviral candidates. [ABSTRACT FROM AUTHOR]