Comparative efficacy of Ocimum sanctum L. and Ocimum basilicum L. essential oils against amyloid beta (1–42)-induced anxiety and depression in laboratory rats

The present study analyzed the possible anxiolytic and antidepressant proprieties of inhaled basil essential oils extracted from Ocimum sanctum L. (Os) and Ocimum basilicum L. (Ob) in β-amyloid (1–42) rat model of Alzheimer’s disease. The anxiolytic- and antidepressant-like effects of inhaled basil essential oils were studied by means of in vivo (elevated plus-maze and forced swimming tests) approaches. The β-amyloid (1–42)-treated rats exhibited the following: decrease of the exploratory activity (number of crossing), the percentage of the time spent and the number of entries in the open arm within elevated plus-maze test and increase of the swimming time and decrease of the immobility time within forced swimming test. The chemical composition varied from one sample to another. The main compounds found in both samples were linalool (31 %–Ob, 19 %–Os), camphor, β-elemene, α-bergamotene and bornyl-acetate, estragole (15.57 and 7.59 %, respectively), eugenol (2.64 and 1.39 %, respectively) and 1,8-cineole (3.29 and 3.90 %, respectively). As a result, exposure to basil essential oils significantly improved the behavior of the animals, suggesting anxiolytic- and antidepressant-like effects. Our results suggest that multiple exposures to basil essential oils can be useful as a mean to counteract anxiety and depression in Alzheimer’s disease conditions.