The efficacy of individual and combined commercial protective cultures against Listeria monocytogenes, salmonella, O157 and non-O157 shiga toxin-producing Escherichia coli in growth medium and raw milk

This study examined the potential of commercially produced PCs when used both individually or in combinations to control Listeria monocytogenes and Salmonella, as well as O157:H7 and non-O157:H7 shiga toxin-producing Escherichia coli (STEC) in growth medium and raw milk. The antimicrobial activity of nine individual PCs and 28 combinations thereof was first determined in growth medium using the cell-free supernatants (CFS). Following the determination of median inhibitory concentrations of individual PCs and their combinations, fractional inhibitory concentration indexes were calculated to classify combinations as synergistic, additive, or antagonistic. Overall, L. monocytogenes was inhibited by lower concentrations of CFS compared to the Gram-negative pathogens. Combinations of PCs with synergistic antimicrobial activity against each pathogen were identified. The efficacy of individual PCs was further determined in raw milk following an incubation time and temperature profile similar to that of cheesemaking and ripening. L. monocytogenes growth was inhibited to counts of ∼6 log and ∼3 log CFU/mL lower than control when cocultured with PCs of Lactococcus lactis or Lactobacillus plantarum, respectively. The protective Hafnia alvei coculture inhibited the growth of STEC O157, non-O157 STEC, and Salmonella enterica to ∼2 log, ∼3.5 log, and ∼3 log CFU/mL lower than pathogen controls, respectively. Potential synergistic activity was noted for the combination of...
Source: Food Control - Category: Food Science Source Type: research

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Abstract We evaluated the bactericidal efficacy of the simultaneous application of ultraviolet-A (UV-A) irradiation and fumaric acid (FA) against Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes in apple juice and as well as investigated the effects of this treatment on product quality. Further, we elucidated the mechanisms underlying their synergistic bactericidal action. Simultaneous UV-A light irradiation and 0.1% FA treatment for 30 min resulted in 6.65-, 6.27-, and 6.49-log CFU/ml reductions in E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectivel...
Source: Food Microbiology - Category: Food Science Authors: Tags: Food Microbiol Source Type: research
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Source: Sensors and Actuators B: Chemical - Category: Chemistry Source Type: research
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Source: Analytical Biochemistry - Category: Biochemistry Authors: Tags: Anal Biochem Source Type: research
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Source: Food Control - Category: Food Science Source Type: research
This study investigated the antimicrobial capacity of yeasts, Saccharomyces cerevisiae and Pichia kluyveri, previously isolated from fermented foods (indigenous beverage, kefir and cocoa) against the adhesion of foodborne pathogens to Caco-2 cells. Co-aggregation of yeasts with pathogens and were evaluated by quantitative analysis and using scanning electron and laser confocal microscopies. All yeasts strains were able to co-aggregate with the tested pathogens, however, this activity was strain-dependent. The inhibition tests showed that the adhesion of Escherichia coli EPEC, Listeria monocytogenes and Salmonella Enterit...
Source: Microbial Pathogenesis - Category: Infectious Diseases Source Type: research
Authors: Hernández-Aquino S, Miranda-Romero LA, Fujikawa H, Maldonado-Simán EJ, Alarcón-Zuñiga B Abstract Lactic Acid Bacteria (LAB) are generally recognized as safe. It has been used to increase the shelf-life of fermented products, and its antimicrobial action is based on the metabolites secretions, such as lactic acid, hydrogen peroxide, reuterin, bacteriocins and the like-bacteriocins substances. It has been proven that LAB are able to inhibit deteriorating bacteria of raw meat, but improper handling of live cultures could lead to spoilage. So, the use of their bacteriocins, smal...
Source: Biocontrol Science - Category: Microbiology Tags: Biocontrol Sci Source Type: research
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Source: Archives of Virology - Category: Virology Source Type: research
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Source: Journal of Molecular Structure - Category: Molecular Biology Source Type: research
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Source: Meat Science - Category: Food Science Source Type: research
CONCLUSIONS: In vitro antimicrobial activity showed that the suspension of ZNPs with 250 ppm concentration could effectively cause a proper reduction and inhibition in the growth of both Gram-positive and Gram-negative microorganisms. Therefore, the results revealed the efficacy of the antibacterial properties of synthesized ZNPs suspension in aqueous media. PMID: 31847595 [PubMed - as supplied by publisher]
Source: Current Eye Research - Category: Opthalmology Authors: Tags: Curr Eye Res Source Type: research
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