Prevalence of Food Poisoning Microorganisms in Bluespot Mullet Meal

Abstract

Fish have a number of bacteria naturally, causing foodborne infections. The present work was conducted to determine the prevalence of Staphylococcus aureus, E. coli, Pseudomonas spp. and Aeromonas spp. in Bluespot mullet and the antibacterial effect of citric acid against the isolated pathogens. S. aureus was detected in 11 and 5 samples representing 44% and 20% of the total examined raw and cooked samples, respectively. Also, E. coli was detected in 6 and 2 samples representing 24% and 8% of the total examined raw and cooked samples, respectively. Pseudomonas spp. and Aermonas spp. were detected in 10 and 5 samples, representing 40% and 20% of the total examined raw bluespot mullet samples, respectively. While they weren’t detected in cooked bluespot mullet samples. The enterotoxigenic strains of S. aureus were detected in 27.27% and 20% of raw and cooked samples, respectively.  Enterotoxins A, A&C and D were 9.09% while enterotoxin A was identified in 20% cooked bluespot mullets. The serological identification of E. coli showed the presence of O156: H7, O127: H6, O125:H21, O15: H12 and O91: H21. P. aeruginosa strains were divided into 2 serotypes P. aeruginosa serotype (O11 group E and O2 group B). pslA, oprL and toxA virulence genes of P. aeruginosa were detected in all examined isolates. Citric acid has great antimicrobial effect against S. aureus, E. coli, P. aeruginosa and Aermonas spp as it causes complete inhibition for them. The findings suggest the application of citric acid during preparation of bluespot mullet is beneficial.