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ARS Home » Northeast Area » Wyndmoor, Pennsylvania » Eastern Regional Research Center » Microbial and Chemical Food Safety » Research » Publications at this Location » Publication #410468
Research Project: Development and Validation of Predictive Models and Pathogen Modeling Programs; and Data Acquisition for International Microbial Databases

Location: Microbial and Chemical Food Safety

Title: Antagonistic activity of bacteriocin-like inhibitory substances from Enterococcus lactis isolated from the surface of jalapeno peppers against foodborne pathogens

Author
item HERNANDEZ-MENDOZA, EZEQUIEL - Center For Research In Food And Development (CIAD)
item PEÑA-RAMOS, ETNA - Center For Research In Food And Development (CIAD)
item Juneja, Vijay
item MARTINEZ-TELLEZ, MIGUEL - Center For Research In Food And Development (CIAD)
item GONZALEZ-RIOS, HUMBERTO - Center For Research In Food And Development (CIAD)
item PAREDES-AGUILAR, MARIA - Center For Research In Food And Development (CIAD)
item VALENZUUELA-MELENDRE, MARTIN - Center For Research In Food And Development (CIAD)
item AISPURO-HERNÁNDEZ, EMMANUEL - Center For Research In Food And Development (CIAD)

Submitted to: Microbiology Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/13/2024
Publication Date: 5/22/2024
Citation: Hernandez-Mendoza, E., Peña-Ramos, E.A., Juneja, V.K., Martinez-Tellez, M.A., Gonzalez-Rios, H., Paredes-Aguilar, M., Valenzuuela-Melendre, M., Aispuro-Hernández, E. 2024. Antagonistic activity of bacteriocin-like inhibitory substances from Enterococcus lactis isolated from the surface of jalapeno peppers against foodborne pathogens. Microbiology Research. 15(2):889-899. https://doi.org/10.3390/microbiolres15020058.
DOI: https://doi.org/10.3390/microbiolres15020058

Interpretive Summary: Lactic acid bacteria (LAB) are capable of producing antimicrobial peptide compounds known as bacteriocins. We investigated the potential of LAB isolated from the surface of jalapeno peppers to produce bacteriocins with antagonistic activity against foodborne pathogens. The findings suggest that LAB possess the ability to produce bacteriocin, possibly enterocin that exhibit a broad-spectrum antagonistic acticvity against common foodborne pathogens such as L. monocytogenes, S. aureus, Salmonella Typhimurium, and E. coli O157:H7. The food industry and regulatory agencies will use LAB as promising natural antimicrobial alternative for the control of foodborne pathogens to ensure food safety and quality.

Technical Abstract: The potential of Lactic acid bacteria (LAB) isolated from the surface of jalapeno peppers to produce bacteriocins with antagonistic activity against foodborne pathogens such as Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella Typhimurium was evaluated. Previously freeze-dried cultures of LAB strains isolated from jalapeno peppers produced in Sonora, Mexico were reactivated, and their cell-free supernatants (CFSs) were obtained to evaluate their antimicrobial activity. Out of the 390 reactivated strains, 60 strains produced CFSs that can be considered bacteriocin-like-substances (BLIS) because their antagonistic activity against L. monocytogenes and S. aureus was lost after the addition of proteases. Subsequently, 16 of those BLIS showed thermo-resistance (HR-BLISs) after heat treatment at 121C for 15 minutes, since their bioactivity was retained. After 16S rRNA gene sequencing and antibiotic susceptibility tests, LAB responsible for producing these HR-BLIS were identified as Enterococcus lactis. Furthermore, four HR-BLIS exhibited a minimum inhibitory concentration (MIC) of 80 mg/mL against L. monocytogenes. Worth mentioning is that Enterococcus lactis (HR-BLIS-67) was capable of prolonging the lag phase of L. monocytogenes growth curve up to 13 h at a concentration of 40 mg/mL. MIC and minimal bactericide concentration (MBC) of HR-BLIS-67 was determined for S. aureus (MIC = 80mg/mL; MBC = 320mg/mL), S. Typhimurium (MIC = 150mg/mL; MBC = 250mg/mL), and E. coli O157:H7 (MIC = 250mg/mL; MBC = 400mg/mL). The results suggest that LAB strains isolated from the surface of jalapeno peppers from Sonora, Mexico, possess the ability to produce HR-BLIS (possibly enterocin) that exhibit a broad-spectrum antagonistic acticvity against L. monocytogenes, S. aureus, Salmonella Typhimurium, and E. coli O157:H7. Furthermore, LAB are promising natural antimicrobial alternative for the control of foodborne pathogens to ensure food safety and quality.