Antimicrobial, antioxidant, anticancer, and antiviral potentials of Weissella paramesenteroides: A promising probiotic

Background: The increasing interest in probiotics is driven by their wide range of health benefits, such as supporting digestive function, enhancing immune response, and reducing the risk of infections. Recent studies further highlight their antimicrobial, antioxidant, anticancer, and antiviral properties, underscoring their broader therapeutic potential. Objectives: This study aimed to isolate a Weissella paramesenteroides strain related to lactic acid bacteria (LAB) and assess its antimicrobial, antioxidant, anticancer, and antiviral activities. Methods: Initially, four bacterial isolates were evaluated based on their morphological features and biochemical properties, including tolerance to acidic conditions, bile salts, and varying concentrations of NaCl. Their antimicrobial activity was tested against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. Antibiotic susceptibility was also assessed. The most promising isolate, W. paramesenteroides, was further examined for antioxidant potential using the DPPH assay, anticancer activity against Caco-2 cells, and antiviral effects against Herpes simplex virus type 1 (HSV-1). Results and Conclusion: paramesenteroides exhibited strong probiotic traits, including high tolerance to 2% bile salts, pH 1.5, and 3.0% NaCl. The cell-free supernatant (CFS) demonstrated notable antimicrobial activity and strong antioxidant capacity (94.9% DPPH scavenging at 1000 µg/mL). Cytotoxicity assays indicated dose-dependent anticancer effects on Caco-2 cells, with reduced toxicity at lower concentrations compared to sorafenib. The CFS also demonstrated moderate antiviral activity against HSV-1 (53.84% inhibition; IC₅₀ = 60.4 µg/mL), although less effective than acyclovir. These results suggest that W. paramesenteroides holds promise as a multifunctional probiotic with potential therapeutic applications.