Novel carotenoids produced on the interaction of the foreign carotenoid ketolase CrtW and endogenous epoxycarotenoids unique to sweetpotato tubers

摘要

Bacterial genes that include the crtW gene encoding carotenoid 4,4'-ketolase were expressed in the tubers (tuberous roots) of sweetpotato, Ipomoea batatas (L) Lam. Consequently, three novel carotenoids with epoxy and keto groups 1, 2, and 3 were found to be produced there. The structures of 1, 2, and 3 were determined as 5',8'-epoxy-5',8'-dihydro-beta,beta-caroten-4-one (named echinenone 5',8'-epoxide), 5',6'-epoxy-5',6'-dihydro-beta,beta-caroten-4-one (named echinenone 5',6'-epoxide), and 3'-hydroxy-5', 6'-epoxy-5',6'-dihydro-beta,beta-caroten-4-one (named 3'-hydroxyechinenone 5',6'-epoxide), respectively, based on spectral data. (C) 2016 Elsevier Ltd. All rights reserved.