Yellow pigments in the wings of Papilio xuthus (papilionid butterfly)

The yellow pigment (Papiliochrome II) of the wings of Papilio xuthus (papilionid butterfly) were extracted, purified with column chromatographies, and examined for chemical and physical properties. Furthermore, the decomposition-products of the pigment were isolated with columm chromatographies and identified. It was found that the pigment readily decomposed on heating to a DOPAmine derivative (SN-1) and kynurenine and that the SN-1 substance was broken down into a DOPAmine derivative (SN-1a) and beta-alanine by hydrolysis in 1 N HCl. These results were confirmed by the injection-experiments of 14C-tryptophan, 14C-DOPAmine, and 14C-beta-alanine. It has been concluded that Papilio-chrome II contains a beta-alanyl DOPAmine derivative and kynurenine as constituents.