Chemical composition and antioxidant activity of essential oils and solvent extracts of Thymus capitatus (L.) Hoffmanns and link from Morocco

Abstract

Analysis of the chemical composition of Thymus capitatus essential oil from Morocco was carried out using gas chromatography (GC) and gas chromatography-mass spectral (GC-MS). The oil was dominated by p-cymene, carvacrol, geranyl acetate and borneol. The amounts of total phenolics and flavonoids in the solvent extracts were determined spectrometrically. The antioxidant activity of essential oil and extracts was evaluated using free radical scavenging. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity increased in the order ethyl acetate > diethyl ether > essential oil. A relationship was observed between the antioxidant activity potential and total phenolic and flavonoid levels of the extracts. Finally, extracts and essential oils of T. capitatus showed antioxidant activity, and therefore it could be used as a natural preservative ingredient in food and/or pharmaceutical industries.   Key words: Thymus capitatus, essential oil, solvent extract, antioxidant activities, phenolic compounds, gas chromatography-mass spectral, 1,1-diphenyl-2-picrylhydrazyl.