Essential oil molecules released from fresh leaves of sweet basil (Ocimum basilicum L.) were collected in
Tenax traps and analysed using a TD-GC/MS. During daytime from 09.00 to 17.00, there were no differences in the content
and composition of total essential oils, however the percentage of eugenol increased slightly. Significant differences
were found in both the total content and composition of essential oils between young and mature leaves. The total content
in young leaves was four times higher than in mature leaves, with fourfold, twofold and sixtyfold differences in the relative
contents of linalool, eugenol and methyl eugenol respectively. There was no difference observed in the relative content
of 1,8-cineole. The results therefore suggest that the defining sampling procedure is important when comparing the
essential oils between treatments.