Effects of Alpinia pricei on the Neuropharmacological Activities in Mice
Alpinia pricei Hayata (Zingiberaceae) is a spicy plant endemic to Taiwan. In this study, several behavioral analyses were used to evaluate the neuropharmacological activity of A. pricei in mice. Oral administration of 100, 300, and 500 mg/kg of A. pricei extract (APE) significantly prolonged pentobarbital-induced sleeping time in mice by 24.5%, 74.7%, and 79.0%, respectively. Also, the antidepressant effect of APE was evaluated using suspended tail and forced swimming tests. The immobility periods of mice in the suspended tail and forced swimming tests were reduced after the administration of APE. Further, an elevated plus-maze test was used to study the anxiolytic activity of APE. After treatment with 500 mg/kg of APE the time the mice spent in the open arms (31.55 ± 13.65 seconds) and the number of times they entered the open arms (51.75 ± 16.51 times) ( P < 0.05) of the plus-maze increased significantly compared to a saline-treated group. Our results also revealed that APE showed potent analgesic activity in the tail-flick test; all dosages of APE prolonged the tail-flick time for up to 90 minutes. In conclusion, APE had a potent effect on the neuropharmacological activities of mice. Finally, the main compounds of APE were separated, and spectral analysis was conducted. The major constituents of APE were characterized as 5,7-dimethoxyflavanone (1), desmethoxyyangonin (2), 2′,4′,6′-trimethoxychalcone (3), cardamonin (4), trans/ cis-3,5-dimethoxystilbene (5), and flavokawain B (6).