Antagonistic Activity of Lactobacillus reuteri Strains on the Adhesion Characteristics of Selected Pathogens

Abstract

Adhesion ability of probiotics is the key factor that decides their colonization in the gastrointestinal tract and potential to inhibit pathogens. Therefore, adhesion ability can be considered as a key determinant for probiotic efficacy. Presents study documents the antagonistic activity of viable/untreated, Lithium chloride (LiCl) treated or heat-killed forms of eight probiotic Lactobacillus reuteri strains on the adhesion characteristics of selected pathogens. All strains investigated were able to adhere to Caco-2 cells. L. reuteri strains tested were able to inhibit and displace (P < 0.05) the adhesion of Escherichia coli ATCC25922, Salmonella typhi NCDC113, Listeria monocytogenes ATCC53135, and Enterococcus faecalis NCDC115. The probiotic strain L. reuteri LR6 showed the strongest adhesion and pathogen inhibition ability among the eight L. reuteri strains tested. In addition, the abilities to inhibit and to displace adhered pathogens depended on both the probiotic and the pathogen strains tested suggesting the involvement of various mechanisms. The adhesion and antagonistic potential of the probiotic strains were significantly decreased upon exposure to 5 M LiCl, showing that surface molecules, proteinaceous in nature, are involved. The heat-killed forms of the probiotic L. reuteri strains also inhibited the attachment of selected pathogens to Caco-2 cells. In conclusion, in vitro assays showed that L. reuteri strains, as viable or heat-killed forms, are adherent to Caco-2 cells and are highly antagonistic to pathogens tested in which surface associated proteins play an important role.

In vitroadhesion and anti-inflammatory properties of nativeLactobacillus fermentumandLactobacillus delbrueckiispp.

“…; Singh et al . ). Lactobacillus fermentum DRL‐36 displayed high adhesion to Caco‐2 cells (>250 adhering bacteria) compared to L. rhamnosus GG (Baccigalupi et al .…”

“…The ability of our strains to adhere to both Caco-2 and HT-29 cells were comparable to the standard probiotic strain of L. rhamnosus GG and is evident by microscopic observation of the adhered bacteria which reveal the nature of their adhesion (aggregates or dispersed). Several reports describe the adhesion properties of lactobacilli to cell lines (Minelli et al 2004;Wulandari et al 2016;Singh et al 2017). Lactobacillus fermentum DRL-36 displayed high adhesion to Caco-2 cells (>250 adhering bacteria) compared to L. rhamnosus GG (Baccigalupi et al 2005).…”

Postbiotics-parabiotics: the new horizons in microbial biotherapy and functional foods

“…It is important to note that non-viable cells maintained their potentiality to deliver beneficial effects on the host at the intestinal level in vivo, thus aid the development of safer preparations with more optimal pharmaceutical properties [37,52]. Heat-killed probiotics revealed anti-adhesion (competition for adhesion sites) ability against various enteropathogens on the Caco-2 experimental model [38]. This promising potentiality of heat-killed probiotics may indicate the ability to fight against diarrheal and food-borne pathogens in terms of their ability to compete for adhesion sites on gut enterocytes.…”

Aplysin Retards Pancreatic Necrosis and Inflammatory Responses in NOD Mice by Stabilizing Intestinal Barriers and Regulating Gut Microbial Composition

“…It should be noted that these species have been regarded as beneficial microbes for health [47,48]. Lactobacillus can regulate the structure of the gut microbiota, limit the intestinal adhesion and overgrowth of potential pathogens, and improve intestinal barrier function [49,50]. Akkermansia is specialized in mucus utilization [51] and also has potential roles in repairing impaired intestinal barriers [52], reducing endotoxemia to regulate inflammatory disorders by increasing mucus layer thickness and antagonizing gut pathobiont colonization [53,54].…”