Changes in Carotenoid Esterification during the Fruit Ripening of Capsicum annuum Cv. Bola

During fruit ripening of pepper (Capsicum annuum), de novo biosynthesis and esterification of carotenoids occur simultaneously. From the very first stages of ripening the totally esterified fraction of xanthophylls is the majority (around 50%). During the ripening process, free xanthophylls decrease in proportion to the rest and at the same time the partial esterified xanthophylls increase in proportion at the expense of the free fraction and simultaneously a portion of the partial esterified xanthophylls are transformed in totally esterified xanthophylls. In the fully ripe fruit the percentages of the free carotenoid pigments and the partially and totally esterified forms of these are 21.3 % ,35.6 % , and 43.1 % , respectively. The fatty acids esterifying yellow xanthophylls are chiefly linoleic ( 18:2A9J2)m, yristic (14:0),a nd palmitic (16:0), whereas in red xanthophylls they are lauric (12:0), myristic (14:0), and palmitic (16:O). This fact helps to explain the greater stability of the red xanthophylls compared to the yellow ones, because of the number of double bonds in the fatty acid chains.We express our sincere gratitude to CICYT (Spanish government) for supporting this research project, ALI 91- 1166-CO3-02.Peer reviewe