Abstract
The major carotenoid pigment obtained from an orange color mutant of C. michiganense is identical with canthaxanthin from the fungus Cantharellus cinnabarinus. The compound appears to be a ketonic carotenoid, showing a single absorption max. in the visible, with a probable formula C40H54O2 ([plus or minus] 2H) and a cross-conjugated carbonyl group. A tentative structure is suggested. Reduction of canthaxanthin yields canthaxanthin-diol, a new carotenoid alcohol.