Isolation and Characterization of Probiotics (Lactobacillus) From Andhra Pickles (Bapatla)

Fermented foods are recognised as natural reservoirs of beneficial microorganisms, particularly lactic acid bacteria (LAB) with probiotic potential. The present study focused on the isolation and preliminary characterization of Lactobacillus species from traditionally prepared Andhra pickles collected in Bapatla, Andhra Pradesh, India. Five homemade pickle samples were analyzed, with fresh curd used as a positive control. Samples were processed using serial dilution and enrichment in de Man, Rogosa, and Sharpe (MRS) broth under anaerobic conditions to promote selective growth of LAB. Preliminary identification was carried out using Gram staining, catalase testing, and carbohydrate fermentation assays. Microscopic examination revealed Gram-positive, rod-shaped, catalase-negative bacteria capable of fermenting glucose with acid production, confirming characteristics typical of Lactobacillus spp. Semi-quantitative estimation based on serial dilution turbidity indicated the presence of LAB in all pickle samples, although in lower abundance compared to curd. Pickle samples showed detectable growth up to 10⁻³–10⁻⁴ dilutions, whereas curd demonstrated growth up to 10⁻⁷ dilutions, suggesting a richer LAB population in dairy fermentation. The findings demonstrate that traditional Andhra pickles serve as a source of viable lactic acid bacteria, though at comparatively lower densities than dairy products. This highlights the potential of regionally fermented vegetable products as alternative probiotic sources. Further molecular identification and functional probiotic assays are recommended to confirm strain-level identity and evaluate health-promoting properties. This study provides baseline data supporting the microbiological value of indigenous fermented foods and encourages future exploration of non-dairy probiotic resources.