Antifungal activity of plant-derived essential oils onCandida tropicalisplanktonic and biofilms cells

Abstract

Dental prosthesis supports Candida species growth and may predispose the oral cavity to lesions. C. tropicalis has emerged as a colonizer of prosthesis and has shown resistance to clinically used antifungal agents, which has increased the search for new antifungals. This work describes the effectiveness of fifteen essential oils (EOs) against C. tropicalis The EOs were obtained by hydrodistillation and were chemically characterized by gas chromatography-mass spectrometry. The antifungal activities of the EOs were evaluated by the microdilution method and showed that Pelargonium graveolens (Geraniaceae) (PG-EO) was the most effective oil. Geraniol and linalool were the major constituents of PG-EO. The 2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide (XTT) assay showed that all the clinical C. tropicalis strains formed viable biofilms. Scanning electron microscopy examination of the biofilms revealed a complex architecture with basal layer of yeast cells and an upper layer of filamentous cells. Treatments with PG-EO, linalool, and geraniol significantly reduced the number of viable biofilm cells and inhibited biofilm formation after exposure for 48 h. PG-EO, geraniol, and linalool were not toxic to normal human lung fibroblasts (GM07492A) at the concentrations they were active against C. tropicalis Together, our results indicated that C. tropicalis is susceptible to treatment with PG-EO, geraniol, and linalool, which could become options to prevent or treat this infection.

Eugenol and linalool: Comparison of their antibacterial and antifungal activities

“…Previous studies confirmed the antifungal activity for clove oil and eugenol against yeasts and filamentous fungi, such as food-borne fungal species (López et al, 2005) and human pathogenic fungi (Chaieb et al, 2007). Antifungal and antibiofilm activity of linalool against C. tropicalis was previously reported (Souza et al, 2016). Researchers found that linalool compound and basil oil which contains high amounts of the monoterpene linalool had antimicrobial activity against S. aureus, B. subtilis, E. coli and Aspergillus niger (Hussain et al, 2008).…”

Antimicrobial Properties of Plant Essential Oils against Human Pathogens and Their Mode of Action: An Updated Review

“…The essential oil of Fortunella margarita exhibited activity against A. niger and C. albicans with a zone of inhibition of more than 30 mm [36]. In a recent study by Souza et al [89], the essential oil of Pelargonium graveolens showed effective inhibitory potential against C. tropicalis , a pathogen resistant to clinically used antifungal agents. The essential oil of P. graveolens was found to be rich in geraniol and linalool.…”

Assay and recommendations for the detection of vapour‐phase‐mediated antimicrobial activities

“…Volatiles are typically enriched in essential oils (EOs), several of which are known for their antimicrobial activity against a wide variety of microorganisms including multi‐resistant strains . Different assays are available to test the antimicrobial activity of the vapour‐phase of volatiles .…”