Abstract
Using primarily electron-capture gas chromatography, bombykol content in female silkworm moths was determined. In virgin females a circadian rhythmic change of bombykol content was demonstrated ranging from 0.4 μg to 1.5 μg per female. No such rhythmic change was detected in mated females and a lower level of bombykol (0.4 μg or less) was constantly observed throughout their lives. Ultraviolet absorbance at 230 mm was not affected by mating, suggesting that bombykol was transformed to other compound(s) still possessing a conjugated-diene chromophore. Relationship between bombykol content and body weight was demonstrated.