The objective is to reveal the influence of the concentration of fragrances on salivary biomarkers , which reflect the human stress system, in 15 female young healthy adults. Lavandula officinalis and Citrus aurantium were used as the test samples.
Salivary biomarkers such as alpha-amylase activity (AMY), cortisol (CORT) and dehydroepiandrosterone (DHEA) were measured during baseline, inhalation and post-inhalation periods.
Our results indicated that (i) a significant difference was not observed for the control and the 3 wt% test samples, however, the alpha-amylase was decreased by inhalation of the 1 wt% test samples (P < 0.05); (ii) AMY levels changed more significantly than did the hormone levels; (iii) a tendency of negative correlation was not observed between DHEA and CORT. It was considered that the time-course change of alpha-amylase might be a useful index of the inhalation of fragrances, which reflects the acute psychosomatic reactivity of humans