Isolation and Identification of the Carotenoid Capsolutein from Capsicum annuum as Cucurbitaxanthin A

Abstract

Capsolutein, a carotenoid pigment mentioned to be present in Capsicum annuum but with an unknown structure, has been isolated. On the basis of spectroscopic (UV-visible, IR, and MS) and chromatographic (TLC and HPLC) behavior, as well as chemical derivatization, it has been identified to be identical with cucurbitaxanthin A (3¢,6¢-epoxy-5¢,6¢-dihydro-â,â-carotene-3,5¢-diol), a peculiar carotenoid containing an 3,6-oxabicycloheptane end group. Hereafter the name cucurbitaxanthin A will be adopted for referring to capsolutein.