Occurrence and Characterization of Staphylococcus aureus (Rosenbach, 1884) in Seafood from Landing Centres and Retail Markets of Thoothukudi, South-east coast of India

摘要

The prevalence of Staphylococcus aureus (Rosenbach, 1884) in 88 samples of seafood from fish landing centres and retail markets of Thoothukudi were analysed. Two hundred and twenty nine isolates were confirmed as Staphylococcus by biochemical tests and these isolates were tested for the production of extracellular enzymes, antibiotic resistance profile and enterotoxin gene profile. There was not much difference in aerobic plate count from freshly landed fish (5.80 x 105 - 5.20 x 106 cfu g"1) and fishfrom market (7.80 x 105 - 1.10 x 107 cfu g"1). Coagulase positive and negative staphylococci were confirmed in 9.09 and 31.82% of the freshly landed seafoods and in 11.36 and 54.55% of the market samples, respectively. Haemolysin, lipase, lecithi-nase,gelatinase and thermostable deoxyribonu-clease enzyme were produced by 73.36, 66.81, 77.29, 79.22 and 46.28% of the isolates, respectively. Five groups of staphylococci classified based on their ability to produce coagulase and other extracellular enzymes were tested for antibiotic susceptibility. Results of antibiotic sensitivity test showed that most isolates were resistant to Penicillin-G and Nalidixic acid, while none was resistant to Gentami-cin. Three genes, sea, sec and seg were detected in S. aureus by PCR. The presence of enterotoxigenic S. aureus in fishes raises concern and calls for proper implementation of better hygienic and sanitary practices both in landing centre and market.