Occurrence of Bacillus cereus in Local Soybean Drinks Sold in Onitsha Metropolis, Nigeria

Abstract

Bacillus species, particularly Bacillus cereus, are significant pathogens in various environments, including food and clinical settings.This study aimed to isolate and characterize Bacillus species from environmental samples and determine their molecular identities. Samples were collected from different locations, and Bacillus species were isolated using standard microbiological techniques. The isolates were characterized using cultural, morphological, and biochemical tests. Molecular identification was performed using 16S rRNA gene sequencing. The study found that 57% of the samples were positive for Bacillus species, with significant variations in occurrence across different locations (p < 0.05). Two Bacillus cereus strains, FORC60 (BCFOR) and DQ01 (BCDQO), were identified, with BCFOR being more prevalent (66.07%). The isolates exhibited consistent cultural, morphological, and biochemical characteristics, including catalase, citrate, and oxidase positivity. Sugar utilization patterns showed significant variations, particularly with lactose, sorbitol, and inositol. Statistical analysis revealed a significant association between location and occurrence of Bacillus species (p < 0.05).  The study highlights the presence of Bacillus cereus in environmental samples, with varying levels of occurrence and characteristics. This study provides valuable data on the prevalence and characteristics of Bacillus cereus in environmental samples, emphasizing the need for monitoring and control measures.