Influence of Harvesting Time on Yield and Composition of the Essential Oil of a Thyme (Thymus pulegioides L.) Growing Wild in Campania (Southern Italy)

Essential oil of the Italian thyme Thymus pulegioides growing wild has been extracted by hydrodistillation from leaves and flowers collected at different growth times. The constituents of the essential oil have been characterized by gas chromatography (GC) and GC−mass spectrometry. Sixty-three compounds have been identified. Essential oils were characterized by a high content of γ-terpinene, p -cymene, thymol, and carvacrol which varied from 57.3 to 62.5% of the total oil content. Essential oil yield and composition vary throughout the vegetation time of the plant. The best time to harvest this species of thyme, for both essential oil yield and phenol content, is during or immediately after the full bloom. Keywords: Thymus pulegioides; essential oil; harvesting time; γ-terpinene; p -cymene; thymol