Depression is a mental disorder with an increased prevalence. Other than conventional antidepressants, essential oils have been used in aromatherapy as a complementary and alternative medicine to reduce depression. In the current study, the antidepressant-like activity of the inhalation of essential oils from Michelia alba (MAEO) and Plumeria alba (PAEO) flowers was analyzed using the forced swim test. The immobility time of mice from tested groups was evaluated statistically by the non-parametric Kruskal Wallis test, followed by the Mann Whitney post hoc test. Also, the characterization of both essential oils was determined by refractive index, solubility, and Gas Chromatography-Mass Spectrophotometry (GC-MS) analysis. PAEO showed stronger antidepressant-like activity than MAEO (p<0.05) and it was equal to the positive control (essential oil of Lavandula angustifolia) (p>0.05). The GC-MS analysis revealed some calming agents in MAEO and PAEO such as linalool, linalyl acetate, phenylethyl alcohol, and methyl anthranilate.

Aromatherapy has been used for centuries to maintain body and mental health. In aromatherapy, the inhalation of essential oil provides physical and psychological benefit due to its volatile bioactive compounds. The current study was aimed to determine the effect of the inhalation of Alpinia galanga essential oil in mice using forced swim test. The refractive index, solubility, and Gas Chromatography-Mass Spectrophotometry (GC-MS) profile of AGEO were also investigated. The essential oil from Alpinia galanga showed an anti-depressive-like effect and it was as strong as the positive control (Lavandula angustifolia essential oil). The GC-MS analysis discovered some antidepressant compounds in the oil such as eucalyptol, fenchone, and α-terpineol.