Biopreservative and Antioxidant Potential of Novel LAB Strains from Low-Sodium Vegetable Fermentations

This study explores the biopreservative and antioxidant potential of lactic acid bacteria (LAB) isolated from low-sodium vegetable fermentations. Five vegetables, green pepper, tomato, eggplant, carrot, and cabbage, were fermented with varying NaCl concentrations (0–3%) for 45 days. Fifty-six presumptive LAB were isolated, and eight LAB strains exhibiting strong antimicrobial activity against Listeria monocytogenes and Staphylococcus aureus were selected for further analysis. The isolates showed significant tolerance to salinity (6.5–18% NaCl), alkaline pH (9.6), and heat stress (45 °C and 60 °C for 30 min). Antimicrobial assays against eight indicator pathogens confirmed a broad inhibition spectrum attributed to bacteriocin-like substances, while antioxidant assays indicated significant antioxidant activity (27–65%), with strain L10 showing the highest radical scavenging potential (p < 0.05). API 20 STREP profiling revealed three dominant taxa: Leuconostoc, Lactococcus lactis, and Enterococcus faecium. These findings highlight LAB as stress-tolerant, multifunctional strains with promising applications as natural biopreservatives and probiotic candidates for developing functional, low-sodium fermented foods.