Figure 1.

A. aestivalis in Flower, Chemical Structure of the Pigment Responsible for the Resplendent Red Color of the Flower Petals, and Structures of Carotenoid Rings Relevant to This Work.

(A) Mature flower of A. aestivalis.

(B) Structure of astaxanthin and of the carotenoid from which it is presumed to be derived, β-carotene. Colors of the structures approximate the colors of the carotenoids they represent. Semisystematic names for the carotenoids (Weedon and Moss, 1995) are in parentheses. Numbering of the carbon atoms is indicated for two positions of interest in the two β-rings of β-carotene.

(C) Structures of carotenoid rings relevant to this work. Carbon numbering for two positions of interest is indicated for the unmodified β-ring (top left). Features of interest are highlighted in red.