Isolation and molecular characterization of citrobacter species in fruits and vegetables sold for consumption in ILE-IFE, Nigeria

Abstract

This study investigated antibiotic susceptibility profile, resistance plasmid DNA as well as resistance and virulence genes of Citrobacter species isolated from fruits and vegetables sold in Ile-Ife, Nigeria. One hundred and fifty (150) fruits and 90 vegetables samples were purchased at Ile-Ife, Nigeria. In all, 25 Citrobacter species were recovered from the vegetables and fruits sampled. All the isolates were 100% resistant to ceftriaxone and amoxicillin, piperacillin (84%), gentamycin (72%), cefotaxime, (60%), and tetracycline (28%). However, isolates were susceptible to ofloxacin, ciprofloxacin, pefloxacin and imipenem. There was significant difference (p < 0.05) in the percentage resistance of the Citrobacter isolates. The selected multiple antibiotic resistant Citrobacter isolates harboured single plasmid of molecular weight of 1710 bp and ceftriaxone resistance was plasmid-borne based on the result of the sensitivity test after plasmid curing. Five of the selected isolates harboured resistance geneblaCTX (585 bp), 3 contained blaSHV(392 bp) each, and only 1 isolate had the virulence gene eae (1917 bp). The fruits and vegetables sold in the study area were contaminated with multiple antibiotic resistant potential Citrobacter species capable of causing food-borne disease in consumers. Keywords: Fruit and vegetables, Antibiotics, Plasmid, Resistance and virulence