Microbial profile, antibiotic sensitivity and heat resistance of bacterial isolates from commercial roasted beef (suya) in Abuja, Nigeria

Abstract

Aim: This study was aimed at determining the prevalence, antibiotic resistance and heat resistance profile of bacterial isolates obtained from ready to eat roasted beef (suya) sold in Abuja, Nigeria.

Methods and Results: Fifty samples of suya were purchased from different vendors within the Federal Capital Territory and assessed for total viable bacterial counts. The sensitivity of the identified bacterial isolates to conventional antibiotics was evaluated using the disc diffusion method. Isolates resistant to at least three antibiotics were assessed for resistance to heat at 55 ^oC, 60 ^oC, 65 ^oC and 70 ^oC for 5 mins, 10 mins and 15 mins. The isolates identified were Staphylococcus aureus (54%), Escherichia coli (4%), Salmonella species (26%), Bacillus species (16%). The total viable bacterial counts ranged from 4.0x 108 - 2.2 x 109cfu/g. Bacillus spp. was found to be most resistant to heat and thrived at 70 ^oC. The other organisms isolated showed varied sensitivity to heat.

Conclusion: Significance and Impact of study: Organisms capable of endangering human lives were isolated from the suya samples and in numbers that could likely cause health problems in healthy and immuno-compromised individuals. The presence of resistant pathogenic bacterial strains in ready to eat roasted beef could be a cause of serious concern which needs to be treated with urgency.

Keywords: Suya, heat resistance, total viable bacterial count