Probiotics potential and antimicrobial properties of Lactobacillus plantarum strains isolated from traditionally fermented maize and cassava and development of antibacterial therapy

Abstract

This study investigated the probiotic potential of Lactobacillus plantarum strains isolated from traditional fermented foods, specifically ogi and corn flour from maize, fufu and tapioca from cassava. Two strains, Lactobacillus plantarum 1 (LP1) (isolated from ogi) and Lactobacillus plantarum 2 (LP2) (isolated from fufu), were characterized for key probiotic attributes. Both strains demonstrated remarkable acid tolerance at pH levels of 3.0 (77.1 and 77.0% survival for LP1 and LP2, respectively) and 4.0 (100% survival for both strains), along with significant bile salt resistance at concentrations of 0.2% (81.0 and 80.9% survival) and 0.3% (85.5 and 83.7% survival) over six hours. The isolates showed strong adhesion capabilities to cancer colorectal-2 (Caco-2) intestinal cells (63.16% for LP1; 60.63% for LP2), exhibited considerable cell surface hydrophobicity (80- and 75-%), auto-aggregation exceeding 50%, and detectable biofilm formation. In antimicrobial assessments, both strains inhibited the growth of Staphylococcus aureus (30- and 26-mm inhibition zones) and Salmonella typhi (30- and 28-mm inhibition zones). Antibiotic sensitivity testing revealed susceptibility to amoxicillin (22- and 21-mm zones), azithromycin (23- and 22-mm zones), and erythromycin (24- and 21-mm zones). These results indicate that L. plantarum strains from indigenous fermented foods possess promising probiotic and antimicrobial characteristics, suggesting their potential application in functional foods and therapeutic formulations.