Microencapsulated Lactobacillus lactis against Salmonella typhimurium, its viability under simulated gastrointestinal conditions and cell adhesion

Abstract

There is significant evidence of the positive health impacts of probiotics in humans and animals, which is why their application has potentially increased in recent years, especially in the food and pharmaceutical industry. In this context, their inhibitory potential has also been explored as a strategy to ensure food safety and biocontrol of pathogens relevant to public health. The objective of the research was to determine the inhibitory effect of microencapsulated Lactobacillus lactis on Salmonella typhimurium and its viability under simulated gastrointestinal conditions. To characterize the lactic strain, a preliminary experimentation was carried out, and based on this information, four inhibition methods were proposed, with different concentrations of the probiotic bacterial supernatant, then the lactic strain was subjected to simulated gastrointestinal conditions, with different pH levels and % of bile and bile salts, and finally the in vitro adhesion assay was performed. Inhibition halos greater than 2 mm (PADS) were found, optimal viability values were observed (3.0x108UFC/mL), adhesion capacity of the strain in cell cultures was evidenced.