Molecular evaluation of sea enterotoxin gene expression in Staphylococcus aures treated with Ginkgo biloba and Zingiber officinale plant extracts

In this study, the antimicrobial effect of extracts of Ginkgo biloba and Zingiber officinale plants against Staphylococcus aureus and their effect on the expression of sea enterotoxin gene were investigated. Two standard and pathogenic strains of S. aureus with enterotoxin sea gene and G. biloba and Z. officinale extracts were used as ready-made tablets with a specified concentration. Antimicrobial test of the extracts was performed by disk impregnation and then the minimum inhibitory and bacteriocidal concentrations of these extracts were evaluated by MIC and MBC tests and SubMIC concentration of these extracts was used to evaluate the effect of extract treatment on the expression of sea enterotoxin gene. Then RNA extraction and cDNA synthesis and finally Real time PCR were performed and the results were interpreted. The results of disk diffusion and MIC showed that Z. officinale extract has antimicrobial effect. Interpretation of Real time PCR results also showed that Z. officinale extract reduced and completely inhibited the expression of sea enterotoxin gene in standard strain ATCC 25923. This extract also significantly reduced the expression of the target gene in the pathogenic strain, and its expression was reduced to 4% compared to the untreated sample. On the contrary, G. biloba extract significantly increased sea gene expression. This extract increased the expression of the target gene in the standard strain and the pathogen by approximately 55 and 9 fold, respectively. According to the results of this study, ginger can be a good candidate to fight S. aureus infections.