Polynuclear aromatic compounds and other constituents of the herb essential oil of Salvia coccinea juss. ex murr.

The essential oils from herb samples of Salvia coccinea Juss. ex Murr. were analysed by GLC, LSC and GC‐MS. The plant material was collected from the same location in Ile‐Ife, Nigeria, in three consecutive years. About 40 components including polynuclear aromatic compounds and their alkyl derivatives were identified in some oil samples. Their major components were acenaphthene (18%), trans‐hex‐2‐enal (11%) and globulol (11%) in 1987, globulol (65%) and aromadendrene (11%) in 1988, and 2,5‐dimethoxy‐p‐cymene (29%) and globulol (16.5 %) in 1989. The polynuclear aromatic compounds detected most likely originate in the plants.