Molecular identification and antifungal potentials of lactic acid bacteria isolated from soil

Abstract

Lactic acid bacteria (LAB) are a large group of bacteria that produce lactic acid as a major end product of fermentation and are found in various environments, including plant materials, gastrointestinal tract of humans and animals. The increasing prevalence of fungal infections and growing resistance of fungi to conventional antifungal therapies necessitate the urgent exploration of new and effective antifungal agents. In this study, LAB were isolated from soil samples from the Botanical Garden of Ahmadu Bello University in Zaria, Nigeria. The fungicidal potency of isolates were tested against some fungi, namely Aspergillus flavus, A. fumigatus A. Brasiliensis, Talaromyces purpureogenus, Penicillium notatum, and Fusarium oxysporum employing the overlay technique. All isolates exhibited potent antifungal activity, with inhibition diameters of 30.2±0.1 to 45.3±0.3 mm. The identity of isolates was confirmed by 16S rRNA sequencing and comparing the sequences with the biological sequences in the National Centre for Biotechnology Information (NCBI) database. The similarity of isolates obtained were 99.74% for Lactiplantibacillus plantarum (KR816154.1), 99.80% for Lactobacillus pentosus (AB362757.1), 99.10% Levilactobacillus brevis (CP031208.1), Lactiplantibacillus plantarum (OQ224994.1) 99.26%, Lactiplantibacillus plantarum (KY203913.1) 99.26% and Lantiplantibacillus plantarum OQ224994.1 99.85%. The phylogenetic relationship established close similarities between Lactobacillus species isolated and other species from NCIB GenBank.