In Vitro Antifungal and Topical Anti-Inflammatory Properties of Essential Oil from Wild-Growing Thymus vulgaris (Lamiaceae) Used for Medicinal Purposes in Algeria: A New Source of Carvacrol
The Pharmaceutical Research Institute, Albany College of Pharmacy and Health Sciences, Rensselaer, New York, NY 12144, USA
Département de Biologie et Physiologie Cellulaire, Faculté des Sciences de la Nature et de la Vie, Université–Saad Dahlab–Blida 1, 270 BP, Blida 09000, Algeria
Clinical Pathology Department, Hematology Unit, Mansoura Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt
Laboratoire de Mycologie, Institut Pasteur d’Algérie, Route du petit Staouéli, Dely-Brahim, Alger 16047, Algeria
Service Pharmaco-Toxicologie, Laboratoire National de Contrôle des Produits Pharmaceutiques, Route du petit Staouéli, Dely-Brahim, Alger 16047, Algeria
Faculté de Médecine, Université Ben Youcef Ben Khedda, Alger I, Algiers 16000, Algeria
Laboratoire d’Anatomie et Cytologie Pathologiques Vétérinaires, Institut Pasteur d’Algérie, Alger 16047, Algeria
Authors to whom correspondence should be addressed.
Sci. Pharm. 2020, 88(3), 33; https://doi.org/10.3390/scipharm88030033
Received: 9 May 2020 / Revised: 28 May 2020 / Accepted: 2 June 2020 / Published: 3 August 2020
The aim of this study is to investigate the Thymus vulgaris essential oil (TVEO) as an antifungal agent in aromatherapy and/or as an active ingredient in the prevention or management of topical inflammatory diseases. The chemical composition of TVEO was determined with gas chromatography and revealed the presence of 25 compounds. Carvacrol was found to be the major component (56.8%). Antifungal action of TVEO was determined in vitro by using different methods. By the disc diffusion method, TVEO showed more potent antifungal activity against Candida strains than the positive control. The diameter of inhibition zone (DIZ) varied from 34 to 60 mm for Candida yeasts. Significantly higher antifungal activity was observed in the vapor phase at lower quantities. Candida albicans and C. parapsilosis were the most susceptible strains to the oil vapor with DIZ varying from 35 to 90 mm. The minimum inhibitory concentrations (MIC) of yeast were determined with an agar dilution method and revealed that MIC varied from 0.3 to 0.15 µL/mL for yeast species. The topical anti-inflammatory potential of TVEO was also explored in vivo with the croton oil-induced ear edema assay. TVEO exhibited a potent anti-inflammatory effect at all doses (100, 10 and 2 mg/kg), which were statistically similar (p > 0.05) to the positive control. This activity was also confirmed at the cellular level with histopathology analysis. Our results suggest the potential application of this carvacrol-rich TVEO in the prevention and management of fungal infections and topical inflammation and deserve further investigation for clinical applications. Furthermore, while the mode of action remains mainly undetermined and should be studied.