Sedative effects of vapor inhalation of agarwood oil and spikenard extract and identification of their active components.

Agarwood oil and spikenard extract were examined for their sedative activity using a spontaneous vapor administration system. It was shown that inhalation of agarwood oil vapor sedated mice. The main volatile constituents of the oil were found to be benzylacetone [agarwood oil from a Hong Kong market (1)], or alpha-gurjunene and (+)-calarene [agarwood oil made in Vietnam (2)]. A hexane extract of spikenard contained a lot of calarene, and its vapor inhalation had a sedative effect on mice. Individual principles benzylacetone, calarene, and alpha-gurjunene were administered to mice, which reproduced the result of the corresponding oil or extract. However, the most effective dose of the compounds was lower than their original content in the oil and extract (benzylacetone 0.1%, calarene 0.17%, alpha-gurjunene 1.5%).