Detection of biofilm-related genes in Streptococcus pyogenes and the impact of Oregano extract on their expression

Objective: This study aimed to evaluate the antibacterial and antibiofilm activities of Oregano extract against clinical isolates of Streptococcus pyogenes, and to assess the presence of biofilm-associated virulence genes (emm, scl1) following treatment. Materials and Methods: Thirty clinical streptococcal isolates were obtained, and twelve were selected based on pathogenicity and multidrug resistance. Species identification and antimicrobial susceptibility testing were performed using the VITEK-2 compact system. Antibacterial activity of oregano extract (0.1 g/ml) was assessed by the agar diffusion method on Muller-Hinton agar. Biofilm formation inhibition was evaluated, and PCR was employed to detect the presence or absence of emm and scl1 genes. Results: Oregano extract at 0.1 g/ml inhibited S. pyogenes growth and prevented biofilm formation. Molecular analysis showed a reduction or absence of emm and scl1 genes in treated isolates, indicating suppression of biofilm-associated virulence factors. Conclusion: Oregano extract demonstrates potent antibacterial and antibiofilm properties against S. pyogenes, likely mediated through inhibition of key virulence genes, suggesting its potential as a natural therapeutic option for biofilm-associated infections.