journal article·2025-10-31Open access

Antimycotic Activity of Essential Oil of Origanum heracleoticum L. from Bulgaria Against Clinical Isolates of Candida spp.

Yana Hristova, Ivan Iliev, Meri Hristamyan, Miroslava Gocheva, Lena Ilieva, Velizar Gochev

Applied Sciences· Volume 15· Issue 21

Abstract

The component composition of Bulgarian essential oil from Origanum heracleoticum L. was determined by gas chromatography and mass spectrometry analysis. Fifty-three different compounds were identified in the essential oil, with carvacrol (70.31–70.52%) and p-cymene (10.86–11.03%) determined to be the main components. The antimicrobial activity of the essential oil was determined against 138 clinical isolates of four species of Candida spp., and it was found to exhibit high antimycotic activity (minimal inhibitory concentration (MIC) between 64 μg mL−1 and 128 μg mL−1) against both fluconazole-sensitive and fluconazole-resistant strains. It was found that Bulgarian essential oil from O. heracleoticum L. disrupts the normal permeability of the cell membrane and inhibits some of the main virulence factors of medically important fungi in the genus Candida by preventing germination, transition to the filamentous stage of growth and the production of hydrolytic enzymes.
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Research context

OpenAlex topics: Essential Oils and Antimicrobial Activity · Antifungal resistance and susceptibility · Sesquiterpenes and Asteraceae Studies

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Department of Biochemistry and Microbiology, Faculty of Biology, “Paisii Hilendarski” University of Plovdiv, 4000 Plovdiv, Bulgaria

Department of Epidemiology and Disaster Medicine, Faculty of Public Health, Medical University of Plovdiv, 4000 Plovdiv, Bulgaria

Scientific and Research Laboratory, Centre for Research Projects and Technological Transfer, University of Food Technologies, 4000 Plovdiv, Bulgaria

Agricultural Academy, Sofia, Institute of Food Preservation and Quality-Plovdiv, 154 Vasil Aprilov Blvd., 4000 Plovdiv, Bulgaria

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