Enhancement of antibacterial compound production in lactic acid bacteria by co- cultivation

Villanueva Adrian  Ray B; Sepelagio  Elma G; Besana  Cyrelle M; Jumao-as  Cromwel M; Tanabe Maria  Elena N

doi:10.18502/jfsh.v11i2.20991

Villanueva Adrian Ray B Department of Biological Sciences, College of Science and Mathematics, University of Southern Mindanao, Kabacan North Cotabato, Philippines
Sepelagio Elma G Department of Biological Sciences, College of Science and Mathematics, University of Southern Mindanao, Kabacan North Cotabato, Philippines
Besana Cyrelle M Department of Biological Sciences, College of Science and Mathematics, University of Southern Mindanao, Kabacan North Cotabato, Philippines.
Jumao-as Cromwel M Department of Biological Sciences, College of Science and Mathematics, University of Southern Mindanao, Kabacan North Cotabato, Philippines.
Tanabe Maria Elena N Department of Biological Sciences, College of Science and Mathematics, University of Southern Mindanao, Kabacan North Cotabato, Philippines.

DOI: https://doi.org/10.18502/jfsh.v11i2.20991

Keywords: Goat milk; Bacteriocins; Food safety; Pathogen inhibition; Antibacterial compounds

Abstract

The rising threat of antibiotic resistance necessitates the development of alternative antimicrobial strategies. Lactic Acid Bacteria (LAB), are GRAS or generally recognized as safe, produce antibacterial compounds with potential applications in food safety and preservation. This study aimed to optimize the production of antibacterial compounds by LAB isolates from goat’s milk through co-cultivation. Three LAB isolates were co-cultivated under varying pH levels (5.5, 6.0, and 6.5) and incubation temperatures (25°C, 30°C, and 37°C). Their antimicrobial activity was evaluated against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus using the Kirby-Bauer disc diffusion method. Co-cultivation significantly enhanced antimicrobial activity compared to individual LAB isolates, producing inhibition zones of up to 22.76 mm against B. subtilis and 17.5 mm against S. aureus. In contrast, weaker inhibition was observed against E. coli and P. aeruginosa, with zones below 12 mm. Co-cultivation of LAB isolates from goat’s milk enhances the yield and efficacy of antibacterial compounds, offering a promising approach for mitigating antibiotic-resistant pathogens and improving food safety applications.