Abstract

Iru (fermented African locust bean, Parkia biglobosa) and Ogiri/Evbarie (fermented melon seed, Citrullus vulgaris) are popular Nigerian condiments, but data on their bacteriological quality are scarce. This study is aimed at determining the bacteriological quality and molecular characterisation of bacteria isolated from fermented African locust bean and melon seed condiments sold in Benin City, Nigeria. One sample of Iru and two samples of Ogiri/Evbarie (A and B) were purchased from different vendors at Oba Market, Benin City, Nigeria. Total viable bacterial counts (TVBC) and total coliform counts (TCC) were determined in triplicate by pour plating. Thirty isolates (ten per sample) were characterised phenotypically and screened for biofilm formation, haemolysis and protease, lipase and cellulase production, and four were identified by 16S rRNA gene sequencing. Results revealed that mean TVBC was highest in Ogiri/Evbarie A (2.58 × 10⁸ CFU/g), followed by Ogiri/Evbarie B (7.97 × 10⁶ CFU/g) and Iru (4.00 × 10⁶ CFU/g); mean TCC ranged from 2.43 × 10³ CFU/g (Iru) to 7.75 × 10⁶ CFU/g (Ogiri/Evbarie A), and both counts differed significantly among the samples (p < 0.001). Presumptive Bacillus (63.3%) and Enterobacter (30.0%) predominated. Biofilm formation and protease activity were each detected in ten isolates, lipase and cellulase activity in seven each, and β-haemolysis in seven presumptive Bacillus isolates, with no significant difference among samples (p > 0.05). Sequencing identified Enterobacter hormaechei and a Priestia megaterium-group isolate from Iru, Staphylococcus kloosii and Micrococcus luteus from Ogiri/Evbarie A and B, respectively (GenBank QB180977–QB180980). High coliform loads recorded in Ogiri/Evbarie and the recovery of E. hormaechei indicate a need for better hygiene in production and retail of these condiments, while the enzyme-producing isolates merit evaluation as starter cultures.