Preliminary Investigation on the Prevalence and Antibiotics Susceptibility Pattern of Bacteria Associated with the Spoilage of Avocado Pear (Persea americana) Sold within Abakaliki, Ebonyi State, Nigeria

Abstract

The prevalence and antibiotic susceptibility pattern of bacteria associated with spoilage of avocado pear(Persea americana) were studied.A total of sixteen (16) avocado pear samples were collected from various markets in Abakaliki and these samples were bacteriologically examined.The five (5) bacterial isolates were characterized and identified on the basis of morphological, Gram staining and biochemical tests. The total aerobic plate count was 3.5 x 105 CFU/g. Out of sixteen samples of avocado pear examined, thirty two bacteria were identified which included Staphylococcus aureus 4 (12.5%), Escherichia coli 10(31.2%), Salmonella species 7(21.8%), Shigella species 5(15.6%) and Klebsiella species 6(18.7%). Escherichia coli 10(31.2%) showed the highest percentage prevalence while Staphylococcus aureus 4 (12.5%) showed the least percentage prevalence. Bacteria isolated from the avocado pear samples were highly resistant to more than 55% of the antibiotics tested in this study. E. coli, Salmonella, Shigella and Klebsiella species isolated were also found to be 100% resistant to ceftazidime and oxacillin. The Salmonella and E. coli were found to be highly resistant to over 50% of the tested antibiotics. However, some of the Salmonella and E. coli isolates were also found to be susceptible to gentanicin, ciprofloxacine and ofloxacin. Shigella, Klebsiella and S. aureus were also found to be susceptible to some of the tested antibiotics including ofloxacin, ciprofloxacin and gentamicin. However, the high rates of resistance found in this study showed that some fruits were heavily contaminated with pathogens that may cause infections in humans when ingested.