摘要:The present paper studies antibacterial activity (AA) and anti-enterotoxigenic activity (AEA) of three Iranian medicinal plant extracts, Origanum majorana, Areca, and Long pepper. In addition, the anti-enterotoxigenic interactive effects of these extracts as herbal extract blend (HEB) were studied. Kirby-Bauer, agar dilution, and Real-time PCR methods were used to study the AA and AEA of the extracts. The statistical method of mixture design was used to optimize and find out the best HEB with the highest AEA on A and B enterotoxins of S. aureus. In individual AA study of extracts, O. majorana extract had the highest AA. Among the extracts evaluated in this study, the extract of O. majorana had much AA on S. aureus and its enterotoxins production. As an interesting result, there is an inhibitory synergistic effect between the extracts studied in this paper on gene expression of sea and seb. The maximum AEA was observed by treat with HEB including 47% O. majorana, 26% Areca, and 27% long pepper.