In vitro evaluation of adherence and anti-infective property of probiotic Lactobacillus plantarum DM 69 against Salmonella enterica.

Gastrointestinal infections are a global health problem, and the potential use of probiotic Lactobacillus species to control such infections represents a promising approach. To exert the health benefits on the host, studying the colonization and adherence properties of probiotic bacteria in vitro is crucial. In this context, investigation was carried out to evaluate adhesion, aggregation and anti-infective effect of an indigenous probiotic Lactobacillus plantarum DM 69 against an enteric pathogen Salmonella enterica subsp. enterica ATCC 35640. The results obtained in this study indicated the strong hydrophobic property of the probiotic candidate. In addition, probiotic strain L. plantarum DM 69 also showed higher percentage of self aggregation (58.66%) and low co-aggregation with S. enterica (23.5%). Investigation on antimicrobial property of the probiotic strain revealed its broad-spectrum activity against S. enterica which may have the potential as antibiotics. On analyzing the antimicrobial compound, infrared (IR) spectroscopy indicated the proteinaceous nature of the compound with a molecular weight of 12010.2751 Da. On evaluating the competitive exclusion properties of probiotic strain we observed that L. plantarum DM 69 and its purified antimicrobial compound could control and inhibit pathogen adhesion and penetration into HCT-116 cells. Probiotic L. plantarum DM 69 and its therapeutic properties must be evaluated further.