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

Abstract

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 fish
from 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, lecithinase,
gelatinase and thermostable deoxyribonuclease
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 Gentamicin.
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.