The essential oil of Apium graveolens var. secalinum and its cercaricidal activity.

The composition of the essential oil of the fresh aerial parts of Apium graveolens var. secalinum at its flowering stage, obtained from three different locations in Egypt, was investigated. The identification of the components of this oil was carried out by means of analytical GC and GC-MS. The main components in the oil are: alpha- and beta-pinene, myrcene, limonene, cis-beta-ocimene, gamma-terpinene, cis-allo-ocimene, trans-farnesene, humulene, apiol, beta-selinene, senkyunolide and neocnidilide. Data concerning the relative concentrations of the main components of the different celery oil samples are given. The cercaricidal effect of the essential oil has been examined on cercariae, being one of the stages in the life cycles of Schistosoma mansoni, which causes schistosomiasis. The essential oil showed in addition to a cercaricidal effect also a chemotactic effect.