Occurrence and enterotoxin gene profiles of Staphylococcus aureus isolated from retail chicken meat

Abstract

The present study was conducted to evaluate the prevalence and enterotoxin gene profiles of Staphylococcus aureus isolated from 120 chicken meat marketed in retail outlets of Chennai, India. It was observed that total of 120 meat samples collected from different retail outlets, 66.67% (80/120) of the samples were positive for the presence of S. aureus based on biochemical characterization and species specific PCR based on thermonuclease gene ( nuc). Enterotoxin gene profiling of the isolates for 9 genes ( sea- sej) revealed that 52.50% (42/80) of the isolates in the present study were enterotoxigenic harboring either one or more gene. It was evident that majority of the isolates harbored seb, followed by seg, sei, sec, sed and sej either alone or in combination. None of the isolates harbored sea, see and seh either alone or in combination. The results of the study clearly indicated higher prevalence of enterotoxigenic S. aureus in retail meat marketed in Chennai, India indicating the potential of retail chicken meat to act as vehicle for food borne intoxication and a major public health threat.

Detection of microbial contamination in chicken meat from local markets in Surabaya, East Java, Indonesia

“…In addition, Kim et al [26] reported that out of 200 chicken meat samples collected in South Korea, 94 were found to be positive (47%) for S. aureus. This number was lower compared to the value reported in Savariraj et al [20], where around 66.67% of samples obtained from in retail outlets in Chennai, India, resulted positive for S. aureus.…”

“…The sample volume was then inoculated into Mannitol Salt Agar (MSA) (Merck 1.05404.0500) and was incubated at 35°C for 24 h. Yellow colonies growing on the MSA were described as positive S. aureus, while red colonies represented other species of Staphylococcus [19]. The suspected colonies were identified by mannitol fermentation, Gram staining, a catalase test, and a coagulase test as per standard protocol [20]. Gram staining was conducted aseptically on the identified colonies.…”

Prevalence, multiple antibiotic resistance and virulence profile of methicillin-resistant Staphylococcus aureus (MRSA) in retail poultry meat from Edo, Nigeria

“…The chain of distribution of the enterotoxin genes from our study was seg>sej>sea>sep>sec>seb>sed>see,she,ser> sei>sek,sel. This was different from those from other studies, such as seb>seg>sei>sec>sed>sej (Savariraj et al, 2020). Kitai et al (2005) reported the distribution of seb>sea>sec>sed.…”

“…Most MRSA isolates by Wu et al (2019) were MDR and harbored ≥1 SE gene, similar to our findings. Lower profiling of SEs (13 -83%) has been documented (Kitai et al, 2005;Li et al, 2018;Savariraj et al, 2020;Tegegne et al, 2021) compared to those of our study. The chain of distribution of the enterotoxin genes from our study was seg>sej>sea>sep>sec>seb>sed>see,she,ser> sei>sek,sel.…”

“…N = Number of expected samples; Z 1-a/2 = Standard normal variant at 5% type I error (P< 0.05); P = prevalence expected based on previous studies [1.3% (Bernier-Lachance et al, 2020), 9.89% (Baghbaderani et al, 2020), 13.9% (Abbasi et al, 2021), 20.5 (Li et al, 2019), 29.1% (Rortana et al, 2021), 35.4% (Tegegne et al, 2021), 66.67% (Savariraj et al, 2020), 89.5% (Lika et al, 2021)]; d = Complete precision or error (which is 5%). Thus, the expected size of the sample was ≥351.…”