Evaluation of Antibacterial Activity of Zataria multiflora Against the Expression of icaADB and aap Gene and Biofilm Formation in Staphylococcus epidermidis

Abstract

Background:This study aimed at evaluating the effect of the extract and essential oil of Zataria multiflora on reducing phenotypes and genotypes of biofilm formation in clinical isolates of Staphylococcus epidermidis. Methods: The ability to produce biofilm was evaluated by microtiter plate (MtP) for phenotype and through the presence of icaADB and aap by PCR for genotype among the 153 clinical isolates of Staphylococcus epidermidis. The impact of ethanol extract and essential oil of Zataria multiflora were measured on biofilm formation in phenotypic evaluation based on MtP and on the expression of ica operon and aap by real time-PCR. Results: The results showed that 71.2% of isolates were able to produce biofilms. The PCR results showed that 52.2% and 88.9% of the isolates had icaABD and aap, respectively. In addition, the relative mRNA expression of icaA, icaD, and aap genes were significantly reduced compared to the negative control after treating the Staphylococcus epidermidis RP62A with subMIC concentration of essential oil and extract (P < 0.001). Conclusions: Given the significant inhibitory effect of the extract and essential oil of Zataria multiflora on biofilm formation, it seems that these substances are good options for studies related to controlling biofilm formation in Staphylococcus epidermidis

Evaluation of anti-biofilm activity of Lactobacillus rhamnosus GG and Nisin on the expression of aap, ica-A and ica-D as biofilm-associated genes of Staphylococcus epidermidis

“…The broth micro dilution method determined MIC and MBC concentrations according to the Mottaghiyan approach ( 20 ). MIC is considered the lowest concentration of an antimicrobial agent capable of inhibiting the visible growth of bacteria after overnight culture.…”

“…To evaluate the effects of Nisin and L. rhamnosus GG on the expression of some biofilm-associated genes ( aap, icaA , and icaD ), the Mottaghiyan approach ( 20 ) was used. S. epidermidis was treated with a sub-MIC amount of Nisin (128 μg/mL) and L. rhamnosus GG (1×10 6 CFU/mL) for 24 h. After that, RNA extraction was carried out using the CinnaPure kit (cat No: PR891620, Cinnagen Co., Tehran).…”