Nature of the antimicrobial activity ofLactobacillus caseiBifidobacterium bifidumandBifidobacterium animalisagainst foodborne pathogenic and spoilage microorganisms

Abstract

The antimicrobial activities as well as the nature of the inhibitory compounds obtained from Lactobacillus casei, Bifidobacterium bifidum and Bifidobacterium animalis strains were assayed on foodborne pathogenic - Staphyloccoccus aureus subsp. aureus (CCUG ATCC® 25926™) and Escherichia coli (ATCC® 25922™) - and spoilage microorganisms - Pseudomonas aeruginosa (ATCC® 27853™). Test producer strains showed inhibitory effect on all indicator microorganisms in diffusion of cell-free concentrated supernatant by agar in well methods (10.0-22.5 mm) in periods of 24, 48 and 72 h. Inhibitory compounds showed no sensitivity to the action of proteolytic enzyme trypsin and were completely inactivated by adjusting the pH of the cell-free 20 × concentrated supernatant to 7.0. The results demonstrated that antimicrobial substances do not have proteinaceous nature and are caused by the action of organic acids with decreasing medium pH.

Characterization and Antibacterial Potential of Lactic Acid Bacterium Pediococcus pentosaceus 4I1 Isolated from Freshwater Fish Zacco koreanus

“…Rodriguez et al (1997) emphasized H 2 O 2 is rapidly degraded in the MRS broth, which excludes the possibility that the antimicrobial activity demonstrated by lyophilized Lactobacilli involves H 2 O 2 , as in this study, MRS was used as the growth medium for the test producer strain and lyophilization was used to concentrate the supernatant for later resuspension. de Oliveira et al (2014) also reported similar findings for lyophilized cultures.…”

Effect of oral administration of Bacillus coagulans B37 and Bacillus pumilus B9 strains on fecal coliforms, Lactobacillus and Bacillus spp. in rat animal model

“…The present investigation was undertaken to explore the antibacterial effect of B. coagulans B37 and B. pumilus B9 on fecal coliform, Lactobacillus , and Bacillus in rat animal model. Despite the information on the antimicrobial effect of probiotic Lactobacillus and Bifidobacterium [ 22 - 24 ], there is a dearth of knowledge on the antimicrobial effect of Bacillus spp. in animal models [ 25 ].…”

Nutrition Related Stress Factors Reduce the Transfer of Extended-Spectrum Beta-Lactamase Resistance Genes between an Escherichia coli Donor and a Salmonella Typhimurium Recipient In Vitro

“…As multi resistant bacteria rise as a problem and are a major health hazard, new reduction measurements are developed to reduce specific bacterial fractions of the intestinal microbiota in animals. Nutritional intervention steps have shown promising results to shift the microbiota towards a more desirable direction [29,30,31,32,33,34]. This may create stress for the suppressed bacteria, causing a change in their metabolic activity, including the transfer of genetic material [35,36,37].…”