Molecular characterization of bacteria isolated from cooked food from restaurants and local eatries (buckas) in Samaru Zaria, Kaduna State, Nigeria

Abstract

Food contains the nutrients that humans and animals need to be healthy, it is eaten to provide energy and nutrition. The etiological factors contributing to foodborne illnesses are the consumption of microbial pathogens, biochemical substances, or biotoxins generated by the microorganisms. The study aimed to investigate the isolation and molecular characterization of bacteria isolates from cooked foods from restaurants and local eateries (Buckas) in Samaru Zaria, Kaduna State. A total of twenty samples (ten samples each for Buckas and Restaurants) were collected from various sites within Samaru Zaria for the analysis. The bacteriological analysis was carried out by isolation and then molecular characterization (using DNA extraction kit, PCR technique and 16SrRNA Sequence identity of the selected bacteria isolates). The growth of the microorganisms was observed and counted per mL. Four species of bacteria were isolated from all the samples which includes: Staphylococcus aureus, Bacillus spp, Proteus spp, and Klebsiella pneumoniae. The food analyzed revealed that Mesophilic count had the highest bacterial load as 7.8 × 10⁶ CFU/g and 8.8 × 10⁶ CFU/g, followed by staphylococcal count of 7.9 × 10⁶ CFU/g with Staphylococcus aureus having the highest frequency of occurrence as 11(55%), followed by Bacillus spp 7(35%) then Klebsiella pneumonia 1(5%), and Proteus ssp 1(5%). Molecular characterization showed the band sizes of the subjected isolated bacterial colonies and sequencing testified the specified bacteria species as S. saprophyticus and B. paramycoides. further studies with the sequencing of Proteus containing isolates obtained from cooked food should be performed to determine their sequence variation and relatedness and also its mechanism of action can be very significant and exploited for further research.