Abstract: In this study, the effect of two exogenous nucleotides, namely, cytidine 5’-monophosphate (5’-CMP) and adenosine 5’-monophosphate (5’-AMP) on the growth of Lactobacillus casei was explored, together with the effects on the biofilm morphology, extracellular polymeric substances and the inhibitory activity of the crude extract from the culture supernatant of L. casei against quorum sensing and the biofilm of foodborne pathogens. The results showed that the two exogenous nucleotides could promote the growth and reproduction of L. casei, and the production of bacterial biofilm and exopolysaccharides (EPS). Moreover, they simulated the quorum sensing inhibitory activity and anti-biofilm activity of the crude extract of L. casei on the biofilm of Shigella spp.. Therefore, the two exogenous nucleotides hold great promise as bacterial growth stimulants in maintaining intestinal health.

Key words: exogenous nucleotides; Lactobacillus casei; cytidine 5’-monophosphate; adenosine 5’-monophosphate; biofilm