Antibiotics Susceptibility Profile of Biofilm-Forming Bacteria Isolated from Soybean Milk Drinks Sold in Abakaliki Metropolis, Nigeria

This study was carried out to determine the antibiotic susceptibility profile of biofilm-forming bacteria isolated from locally produced soybean milk drinks sold within the Abakaliki metropolis. A total of 150 soybean milk samples comprising 15 samples from each location were collected using random sampling techniques from 10 different locations namely Nkaliki, Presco Junction, Azugwu, Kpirikpiri, Ahiaofu, Mile 50, Rice mill, Mechanic site, international market and Abofia area of Abakaliki town in Ebonyi State metropolis. The collected soybean milk samples were analyzed for the presence of bacteria using standard microbiology techniques which include; culturing, Gram staining and biochemical tests. The screening for biofilm formation on isolated bacteria species was done using the tube method. The antibiotic susceptibility profile of the isolated biofilm-forming bacteria was determined using the disc diffusion method. The result showed that a total of 100 (66.6%) bacteria were isolated from the locally produced soybean milk comprising of 5 bacteria genera namely: Staphylococcus aureus 25 (25%), Escherichia coli, 27 (27%), Pseudomonas aeruginosa 10 (10%), Klebsiella species 15 (15%) and Salmonella species 23 (23%). The biofilm production screening test revealed that Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa are biofilm-forming bacteria (are all the isolated bacteria of S. aureus, K. pneumoniae and P. aeruginosa all biofilm producers. The antibiotic susceptibility profile of biofilm-forming bacteria varies between antibiotics. The result showed that all Staphylococcus aureus isolates were (100%) susceptible to ceftazidime, 80% resistant to imipenem and 72% resistant to ciprofloxacin, Pseudomonas aeruginosa, isolates were 100% and 80% resistant to cefoxitin and ofloxacin while E. coli isolates were 70.3% and 63% resistant to ofloxacin and cefotaxime respectively. The study showed the poor hygienic quality of locally produced soybean milk marketed within the Abakaliki metropolis and this call for public awareness as it could be the source of disease outbreak/spread within this community.