Bioactive Potential of Indigenous Lactobacillus Species Isolated from Algerian Ouarsenis Honey: A New Source of Natural Antibacterials

Abstract

Background: This study explores the unexplored microbial diversity of raw Apis mellifera honey from Algeria’s Ouarsenis region to identify novel biotherapeutic agents. Methods: Nine honey samples were screened, yielding lactic acid bacteria (LAB) isolates characterized via phenotypic assays and identified through MALDI-TOF MS (Bruker Biotyper). The isolates were taxonomically classified as Lactiplantibacillus plantarum, Limosilactobacillus fermentum, Apilactobacillus kunkeei and Fructobacillus fructosus. To determine their functional potential, the antibacterial efficacy of both whole cultures and cell-free supernatants (CFS) was evaluated against Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus using agar diffusion. Result: The isolates exhibited potent antagonistic activity, with inhibition zones reaching 39.5±0.71 mm for whole cultures and 24.0±0.00 mm for CFS. S. aureus was the most susceptible pathogen. These findings highlight that honey from the Ouarsenis region serves as a unique ecological niche for bioactive LAB. These strains possess significant inhibitory properties against clinically relevant pathogens, positioning them as promising natural alternatives to conventional antibiotics and high-value candidates for probiotic or food preservative applications.