Abstract:
Vibrio species account for a significant number of foodborne infections from
the consumption of raw or improperly cooked seafood and contaminated water with
human feaces or sewage. The study was conducted to determine beta-lactamases
production in ampicillin resistant Vibrio species isolated from seafoods collected from
Ondo State coastal area. A total of one hundred and six (106) samples comprising of
10 crabs, 54 fishes, and 42 shrimps were collected from local fishermen in Erun-
Amoh, Ilaje. All the samples were analyzed using standard microbiological methods.
Isolated Vibrio species on Thiosulfate Citrate Bile-Salt Sucrose (TCBS) agar were
subjected to antibiotic susceptibility testing by disc diffusion method. Double disc
synergy test was used to determine the beta-lactamase in ampicillin resistant isolates.
The genetic basis of the resistance was confirmed by plasmid profiling and plasmid
curing techniques. From the results, average bacterial counts was high in shrimp with
5.0×107 cfu/g and low with 2.0×105 cfu/g. Also, average bacterial counts was high in
crab with 19×107cfu/g and low with 2.0×105 cfu/g. Whereas, in fish average bacterial
counts was high with 25×107 cfu/g and low with 3.0×105 cfu/g. Bacteria of the genera
Bacillus, Enterobacter, Enterococcus, Escherichia, Proteus, Pseudomonas,
Salmonella, Staphylococcus, and Vibrio were identified including agents of diarrhoea
from seafoods. Beta-lactamases production was confirmed in two (2) V. cholerae
strains that were ampicillin resistant. However, the isolates showed high degree of
sensitivity to ofloxacin. Plasmids of molecular weight ranging from 3.8Kbp to 9Kbp
were isolated from the three (3) Vibrio cholerae. Though, plasmid curing was
successful in the third V. cholerae isolate but 9Kbp plasmids were not cured in first
and second V. cholerae isolates. Post-curing sensitivity revealed that the V. cholerae
strains were resistant to ampicillin and some antibiotics but, with high degree of
sensitivity to ofloxacin, levofloxacin, gentamycin cefexime, ciprofloxacin,
ceftriaxone-sulbactam, cefuroxime, and augmentin. Though, most of the identified
bacteria inhabit naturally in marine water environment, but contaminate seafood from
human waste from faecal or urine contamination. The diversity of potential pathogens
from the samples of seafoods; and the emergence of multiple antibiotic resistant
ESBLs-producers Vibrio species and other pathogens is of serious Public Health
concern posing a threat of poisoning when the contaminated water or seafood is
consumed in quest to get nutritious food.
