Antifungal effects of the essential oil from Thymus vulgaris L. and comparison with synthetic thymol on Aspergillus niger

The antifungal effects of the essential oil from Thymus vulgaris L. and comparison with synthetic thymol on Aspergillus niger growth was studied. The chemical composition of the essential oil of T. vulgaris, the aerial parts of this plant which is grown in a village in Kerman Province at full flowering stage in June 2012 were collected. The sample was cleaned, dried in the shade and hydro distillation method was performed for the extraction of essential oil. The main oil content from the plant of T. vulgaris was 2.25% (v/w). Essential oil was analyzed by capillary gas chromatography (GC) using flame ionization (FID) and capillary gas chromatography coupled mass spectrometry (GC/MS) for detection. Thirty-two compounds were identified in the essential oil of T. vulgaris that concluded 99.56% of the total oil. The major components were Thymol (32.67%), P-cymene (16.68%), γ-terpinene (12.65%) and Carvacrol (8.32%). The study of antifungal effects of the oil sample was tested against strain ofA. niger (PTCC=5223) fungi by disc diffusion method via average inhibition zone. The results show that essential oil from Thymus plant at 1, 1/2 and 1/4 oil dilutions exhibits strong antifungal activity than Streptomycin sulphate (72% SP) and gentamycin (8 mg/ml) antibiotics on A. niger and that exhibited on strong synthetic thymol was at 10% dilution. The high percentage antifungal activities of Thymus oil are related with thymol is a natural monoterpenephenol as the main compound.   Key words: Thymus vulgaris L., Aspergillus niger, essential oil, antifungal activity, fungal growth, thymol.