Antimicrobial Activity of Lactic Acid Bacteria Starters against Acid Tolerant, Antibiotic Resistant, and Potentially Virulent E. coli Isolated from a Fermented Sorghum-Millet Beverage
2019
Byakika, Stellah | Muzira Mukisa, Ivan | Mugabi, Robert | Muyanja, Charles
Bacterial contamination of fermented foods is a serious global food safety challenge that requires effective control strategies. -is study characterized presumptive E. coli isolated from Obushera, a traditional fermented cereal beverage from Uganda. -ereafter, the antimicrobial effect of lactic acid bacteria (LAB) previously isolated from Obushera, against the E. coli, was examined. -e presumptive E. coli was incubated in brain heart infusion broth (pH � 3.6) at 25°C for 48 h. -e most acid-stable strains were clustered using (GTG)5 rep-PCR fingerprinting and identified using 16S rRNA sequencing. E. coli was screened for Shiga toxins (Stx 1 and Stx 2) and Intimin (eae) virulence genes as well as antibiotic resistance. -e spot-on-the-lawn method was used to evaluate antimicrobial activity. Eighteen isolates were acid stable and are identified as E. coli, Shigella, and Lysinibacillus. -e Stx 2 gene and antibiotic resistance were detected in some E. coli isolates. -e LAB were antagonistic against the E. coli. Lactic acid bacteria from traditional fermented foods can be applied in food processing to inhibit pathogens. Obushera lactic acid bacteria could be used to improve the safety of fermented foods.
显示更多 [+] 显示较少 [-]