Preventive effects of Lactobacillus plantarum ST-III against Salmonella infection

Salmonellosis is one of the world's most leading epidemic diseases and poses a great threat to public health. Probiotic administration is an effective strategy to cope with pathogenic infections with few side-effects and a high safety profile. Lactobacillus plantarum ST-III is a probiotic with reported cholesterol-lowering activity. In this study, we investigated the preventive effects of L. plantarum ST-III against Salmonella infection in a mouse model. L. plantarum ST-III pretreatment significantly decreased the lethal effect of Salmonella. Further studies showed that several mechanisms are involved in this preventive effect, including (1) inhibition of the growth of Salmonella; (2) enhancement of intestinal barrier functions to defend against Salmonella invasion; (3) promotion of the Th1 response to deter systemic spread; and (4) induction of anti-inflammatory effects during infection. Our results suggest that L. plantarum ST-III has great potential to control the prevalence of food-borne pathogens as supplement in functional food products.