AUTHOR=Sen Pooja , Gupta Lovely , Vijay Mukund , Vermani Sarin Maansi , Shankar Jata , Hameed Saif , Vijayaraghavan Pooja 

TITLE=4-Allyl-2-methoxyphenol modulates the expression of genes involved in efflux pump, biofilm formation and sterol biosynthesis in azole resistant Aspergillus fumigatus

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2023.1103957

DOI=10.3389/fcimb.2023.1103957

ISSN=2235-2988

ABSTRACT=<sec><title>Introduction</title><p>Antifungal therapy for aspergillosis is becoming problematic because of the toxicity of currently available drugs, biofilm formation on host surface, and increasing prevalence of azole resistance in <italic>Aspergillus fumigatus</italic>. Plants are rich source of bioactive molecules and antimicrobial activity of aromatic bioactive compounds draws attention because of its promising biological properties. The present study elucidated the antibiofilm activity of 4-allyl-2-methoxyphenol (eugenol) against azole-resistant environmental <italic>A. fumigatus</italic> isolates.</p></sec><sec><title>Methods</title><p>Soil samples were collected from agricultural fields across India; azole-resistant <italic>A. fumigatus</italic> (ARAF) were isolated followed by their molecular identification. Antibiofilm activity of eugenol was calculated via tetrazolium based-MTT assay. The expression of the multidrug efflux pumps genes <italic>MDR1, MDR4</italic>, transporters of the <italic>MFS</italic> gene, <italic>erg11A</italic> gene encoding 14α demethylase, and transcription regulatory genes, <italic>MedA</italic>, <italic>SomA</italic> and <italic>SrbA</italic>, involved in biofilm formation of <italic>A. fumigatus</italic> were calculated by quantitative real time PCR.</p></sec><sec><title>Results</title><p>Out of 89 <italic>A. fumigatus</italic> isolates, 10 were identified as azole resistant. Eugenol exhibited antibiofilm activity against ARAF isolates, ranging from 312 to 500 µg/mL. Confocal laser scanning microscopy analysis revealed absence of extracellular matrix of ARAF biofilm after eugenol treatment. The gene expression indicated significantly low expression of efflux pumps genes <italic>MDR1</italic>, <italic>MDR4</italic>, <italic>erg11A</italic> and <italic>MedA</italic> in eugenol treated ARAF isolates when compared with untreated isolates.</p></sec><sec><title>Conclusions</title><p>Our results demonstrate that eugenol effects the expression of efflux pump and biofilm associated genes as well as inhibits biofilm formation in azole resistant isolates of <italic>A. fumigatus</italic>.</p></sec>