MOLECULAR CHARACTERIZATION OF PATHOGENIC MICROORGANISMS ISOLATED FROM SELECTED SEAFOODS IN IGBOKODA, ONDO STATE, NIGERIA

Abstract

Seafood is part of a healthful diet, but its consumption is not risk-free because of sea contaminations by anthropogenic activities and environmental factors, hence the need for proper assessment of the microbial quality. This study characterizes pathogenic microorganisms isolated from sea snail and shrimp in Ugbo nla, Igbokoda, Ondo State. During this study, snail i.e. Achatina achatina (97) and shrimp i.e. Penaeus notialis (106) samples were collected once a week for six weeks from Atlantic line at Ugbo nla, Igbokoda in a clean sterile container and transported in ice pack to the laboratory for microbiological analysis. Weights and lengths of the seafood samples were measured with analytical balance and meter rule respectively, isolation and identification of microorganisms from snail and shrimp were carried out, using standard microbiological method, disc and agar well diffusion method were used for antibacterial and antifungal susceptibility test respectively. Effects of salt concentration and temperature on isolated microorganisms and 16sRNA and 18sRNA gene sequence on bacteria and fungi respectively were carried out. The mean standard length and weight of shrimp used in this study were 97.20 mm and 25.86 g respectively while snails were 97.00 mm and 78.04 g respectively. Total bacterial and coliform counts of shrimp ranged from 2.77 to 2.10 106 cfu/g and 7.67 to 5.00 104 cfu/g respectively while snail ranged from 4.63 to 3.97 106 cfu/g and 16.33 to 11.33 104 cfu/g respectively. Fungal counts ranged from 5.00 to 3.00 102 sfu/g and 2.67 to 2.00102 sfu/g in shrimp and snail respectively. Klebsiella oxytoca (16.09%) and Aspergillus flavus (55.0 %) were the most occurred bacteria and fungi respectively in selected sea foods. The bacterial isolates were mostly resistant to Augmentin, Ceftriaxon, Nitrofuratoin, Cotrimoxazole, Amoxicillin and Tetracycline while itraconazole was most effective against fungi. Molecular identification revealed the presence of Proteus mirabilis LZPM-03, Pantoea agglomerans BJCP2, Pseudomonas aeruginosa R8-589, Klebsiella pneumoniae 2N3, Serratia marcescens, Alcaligenes faecalis ACBC1, Yersinia. pseudotubercules YPIII, Escherichia coli 2A, Lysinibacillus sphaericus C3-41, Listeria monocytogen J1776, Staphylococcus aureus and Proteus mirabilis LCX20 while the fungi are Fusarium proliferatum FproStRINI, Aspergillus flavus NRRL3357, Aspergillus oryzae RIB40 and Aspergillus peniciliodes. Post plasmid curing resistance patterns of the bacteria isolates reveled that some resistance are plasmid mediated. 4% salt concentration at 450C after 18 hours inhibited bacterial growth on the seafood. The presence of pathogenic bacteria in the sea foods and occurrence of antibiotic resistance bacteria could make them a potential health-risk when consumed without proper cooking.