Isolation of 24-methylenecholesterol-derived oxidation products from queen honeybee ovaries (Apis mellifica L.).

The bioecological situation of 24-methylenecholesterol, the main sterol of many pollens and previously isolated from larvae, workers, and queens of the honeybeeApis mellifica L., is reviewed. A search for steroids in queen honeybee ovaries has led to the isolation of three compounds occurring in minute amounts: 24-methylenecholest-4-en-3-one (1), 24-oxochoiesterol (2), and 24-oxocholest-4-en-3-one (3), which were identified by direct comparison with authentic samples prepared from 24-methyienechoiesterol. These three substances have not been detected in lipids from other parts of queen or from worker honeybees, and their presence may reflect a particular oxidizing capability of the ovaries. The results so far observed are discussed in relationship with previous observations reported on honeybees.