The study was conducted to evaluate the efficacy of tiptop yogurt as a some of probiotics against enteric pathogens isolated at KIU-TH. It was conducted to isolate and identify any probiotics available in yogurt, obtain cell free supernatants (bacteriocins) and expose them to 0 selected enteric pathogens, evaluate the effect of bacteriocins from individual isolates and the combination of the bacteriocins on the pathogens. Ciprofloxacin 50mg/ml was used as a positive control. It was hypothesized that yo gmt contained isolable probiotics capable of inhibiting growth of enteric pathogens. The study was carried out at KIU-TH microbiology laboratory, isolates were obtained by culturing yoghurt using MRS/CLC and M17 agars, the munber of bacteria were enumerated by counting CFU's whereas the inhibition was established by exposing Salmonella typhi and Escherichia coli to bacteriocin extracts from probiotic isolates and measuring their optical density. It was found out that tiptop yogurt contained viable probiotics, the probiotics were capable of inhibiting enteric pathogens by producing bacteriocins and that combination of probiotics was more effective compared to single probiotic bacteria hence suggesting a mutual synergistic effect in their action on pathogenic bacteria. There is need for more research i.e. in characterization and isolation of the bacteriocins that were responsible for inhibiting the growth of E. coli and S.typhi in this research.
