Ecdysteroids in the ovary and the egg of the greater wax moth

Galleria mellonella eggs exhibit a remarkably high molting hormone activity, equivalent to 74 μg/g fresh wt of ecdysone or ecdysterone. The activity in the ovary was also substantial, averaging 0.4 and 0.58 μg/female, respectively, in the pharate adults and in the 1-day-old adults. Seven ecdysteroids were isolated from the eggs. Ecdysone and ecdysterone were the principal components, comprising 80% of the total biological activity, followed by their 3-epimers and three unidentified ecdysteroids with less biological activity. Five of the seven ecdysteroids were found in the ovaries of the pharate adults and six in the 1-day-old adults. In both the ovary and the egg, 80–85% of these ecdysteroids existed in the conjugated form, mainly as sulphates, and were partitioned in both the n-butanol and the water phases. The ratio of these ecdysteroids changed significantly from the ovary to the egg, with ecdysone decreasing, ecdysterone increasing, and the others increasing slightly. The results suggest that these ecdysteroids exist in a dynamic state and are not merely inactivation products or storage forms.