(Z)-11-eicosen-1-ol, a major component of Apis cerana venom

The unusual venom of Apis cerana contains large oily droplets within an otherwise aqueous secretion. Chemical analysis (CC-MS) revealed that the venom oil consists of (Z)-11-eicosen-1-ol (81.2%), other linear alcohols (7.7%), and linear hydrocarbons (11.1%). The eicosenol is present in extremely large quantities, averaging over 250 mu g per insect, and is absent, or present in small quantities, in other parts of the sting apparatus. An investigation of the site of eicosenol storage in A. mellifera showed it to be absent from the venom and to be associated with the setose area where the more volatile components of the alarm pheromone are stored, as previously shown by others. A third honeybee species, A. dorsata, does not to contain the alcohol. The function of eicosenol in A. cerana in not clear, but may serve to mark stung intruders with pheromone or to attract foragers to marked floral resources.