Antibiotic sensitivity patterns and molecular detection of Enterotoxin genes in Staphylococcus aureus isolated from frozen muscle foods

Abstract

Stapylococcus aureus is considered to be the most common pathogen in commonly consumed and improperly stored frozen foods. Hence, this study investigated the antibiotic sensitivity patterns and the occurrence of enterotoxin genes (sea and seb) in S. aureus isolated from frozen poultry meat of chicken, turkey and fish, namely Trachurus trachurus, Scomber scrombus and Merluccious merluccious. A total of 500 samples of raw meat from chicken (n = 130), turkey (n =130), and different fish (n =240) were randomly purchased from various markets and shopping malls in Akure between September 2020 and December 2021. The antibiotic sensitivity of isolated S. aureus was determined by disk diffusion method. S. aureus was analyzed for enterotoxin genes by multiplex polymerase chain reaction (PCR). The highest staphylococcal count (7.70 ×105 CFU/g) was observed in T. trachurus. One hundred and twenty five S. aureus were isolated from meat and fish with the highest occurrence (40.80%) in turkey meat. S. aureus is highly resistant (33.3 to 100%) to the tested antibiotics. The PCR assay, respectively, showed sea and seb coded for staphylococcal enterotoxin A and B. The presence of staphylococcal enterotoxin A and B in frozen muscle foods could be attributed to unhygienic conditions during processing and storage. The occurrence of antibiotic resistant and enterotoxigenic S. aureus in muscle foods could pose a serious threat to people when consumed. Hence, urgent attention is required to avert the incidences of staphylococcal food poisoning after consuming frozen meat and fish.