Bacteriocin production of the probiotic Lactobacillus acidophilus KS400

Abstract

In the last years, the use of probiotics, including Lactobacillus species, has received much attention to prevent and treat vaginal disorders. These species have been described as having the ability to colonize the epithelial surface and produce antimicrobial metabolites that are able to control the remaining vaginal microflora. This study aimed to identify and characterize, for the first time, a bacteriocin natively produced by Lactobacillus acidophilus KS400 (probiotic strain from Gynoflor®-Medinova AG, Switzerland) and its antimicrobial activity against relevant urogenital pathogens. After organic acids and hydrogen peroxide neutralization in the fermented Lactobacillus acidophilus KS400 culture medium, bacteriocin activity was tested against the indicator microorganism Lactobacillus delbrueckii ATCC9649. The fermentation of Lactobacillus acidophilus KS400 for bacteriocin production was carried out in batch mode, and its antimicrobial activity, optical density and pH were monitored. After production and extraction, the bacteriocin molecular weight was estimated by electrophoresis and tested against vaginal pathogenic microorganisms. As described for other bacteriocins, batch fermentation profiles indicated that bacteriocin production occurs during the exponential growth phase of the lactobacilli, and declines during their stationary growth phase. The molecular weight of the bacteriocin is approximately 7.5 kDa. The bacteriocin containing protein extract was shown to inhibit the growth of Gardnerella vaginalis, Streptococcus agalactiae, Pseudomonas aeruginosa and the indicator strain Lactobacillus delbrueckii ATCC9649. We conclude that L. acidophilus KS400 produces bacteriocin with antimicrobial activity against relevant urogenital pathogens.

Antibacterial Effectiveness of Fecal Water and In Vitro Activity of a Multi-Strain Probiotic Formulation against Multi-Drug Resistant Microorganisms

“…Starting from the above assumption, it is explained why the in vitro tests for antibiotics are always more "brilliant" than the results obtained in vivo. On the contrary, for probiotics, considering the interaction of these live organisms in the gut, it may be possible that in vivo, they are far more effective than in vitro, where only their capability to produce bacteriocins is taken into consideration [14].…”

Comparative Genomics of the Transport Proteins of Ten Lactobacillus Strains

“…The ability of these organisms to produce lactic acid and other metabolites helps to kill pathogenic microbes [ 10 ]. Among these metabolites there are antimicrobial proteins called bacteriocins; these are small proteins or peptides that are ribosomally synthesized and are effective at killing pathogenic microbes [ 11 ]. Other beneficial effects of lactobacilli include regulation of the immune system, maintenance of normal intestinal homeostasis, improvement of gastrointestinal barrier function and suppression of proinflammatory cytokines [ 12 , 13 , 14 ].…”

The Effect of the Hydrolyzates of Keratin- and Collagen-Containing Wastes of Poultry Processing in the Diets for Broilers on the Cecal Microbial Community

“…The interesting changes were found in the concentrations of certain species obligate for the avian intestine (lactic bacteria from Lactobacillus and Enterococcus geni, Bifidobacteria) and capable to the antagonistic exclusion of pathogenic species (including salmonellas, Protea, Staphylococci, coliforms, Pseudomonas, Streptococci) due to the release of volatile organic acids and bacteriocins [45].…”