Quantitative Bestimmung der hydrierten Pterine und des Xanthommatins in den Augen von Ceratitis capitata WIED (Dipt. Trypetidae)

Abstract

In the eyes of male and female flies a quantitative determination of the tetrahydropterin, the corresponding dihydro-compound (Sepiapterin) and of xanthommatin from 0-5 days after hatching was made. The increase of xanthommatin almost stops 24 hours after hatching; about 13[mu]g are present after that time. The tetrahydropterin, after a drastic increase during the first 24 hours, remains at a level of about 1,1-1,2 [mu]g. In contrast the dihydro compound which is nearly absent at the time of hatching is deposited on the eye-granules between the third and fifth day. At that time, especially in the male the dihydropterin/tetrahydropterin ratio is increased. Starvation during the first 24 hours has essentially no effect on the amount of xanthommation whereas the amount of pterins is markedly reduced.