The Effect of Z ataria multiflora Boiss. Essential Oil on Gene Expression of Enterotoxin C in S taphylococcus aureus ATCC 6538

Abstract

This study was designed to evaluate the chemical constituents of Zataria multiflora Boiss. essential oil (EO) and its inhibitory effect on enterotoxin type C production by Staphylococcus aureus ATCC 6538. Moreover, the effect of this EO on gene expression of staphylococcal enterotoxin type C (SEC) was assessed. The effect of different concentrations of EO on enterotoxin C production was evaluated using 3-enzyme-linked immunosorbent assay. The reducing effect of EO subinhibitory concentrations on gene expression of enterotoxin was assayed using real-time polymerase chain reaction as well. EO at the level of 0.005% had no inhibitory effect on enterotoxin C production, and by increasing the subinhibitory concentration of the EO to 0.015%, an inhibitory effect was observed. Comparing the relative gene expression of SEC in control and treatment groups showed that the EO concentrations of 0.0075 and 0.015% had a significant downregulation (10.7 and 23.8 times, respectively) of sec gene. Practical Applications This research raises important implications for the potential use of Zataria multiflora Boiss. essential oil as a natural preservative and a new approach for biocontrol of Staphylococcus aureus. Besides, it can provide additional knowledge of the mechanisms involved in EO against S. aureus intoxication based on gene expression and open new avenues for the biocontrol of this microorganism in food industry and/or the extension of the shelf life of processed foods.