Phytochemical composition of essential oil from seeds of Zingiber roseum Rosc. and its antispasmodic activity in rat duodenum.

A combination of GC and GC-MS revealed the presence of 60 compounds out of which 47 compounds (96.2% of the oil) were identified in the essential oil of seeds of Zingiber roseum Rosc., the major compounds being alpha-pinene, beta-pinene, limonene, p-cymene, alpha-terpineol and verticiole. The unique feature is the dominant presence of mono- and sesquiterpene hydrocarbons which make about 82% of the oil. The oil showed myorelaxant activity on isolated rat duodenal smooth muscle. The Zingiber roseum seed essential oil (ZRSEO) relaxed both cabachol- and KCl-induced contractile responses with IC(50) of non-significant difference. The results confirm a common mechanism in both the types of action of ZRSEO and suggests a probable inhibitory effect of ZRSEO on influx of Ca(2+) through cell membrane of rat duodenal smooth muscle.