Unusual carotenogenesis in fruits with pronounced anthocyanic ripening (Olea europaea Var. Arbequina)

Fruits of the Olea europaea Arbequina variety showed a carotenogenic stage overlapping the biosynthesis of anthocyanins. At the start of ripening, the carotenoid concentration increases (20%) or is maintained (besides the esterification of xanthophylls found in this variety), compared with a decrease (30%) found in the same period in the Picual variety (used as a control that was representative of the rest of the varieties). Both the beta,beta and beta,epsilon carotenoid series were found to be implicated in this carotenogenic process. Differences in both varieties for the chlorophyll a/b ratio, chlorophylls/carotenoids ratio, and relative carotenoid composition may indicate the existence of a different metabolism of chloroplast pigments, but also indicates a different structure and function of the photosynthetic apparatus. This fact shows that the photosynthetic behavior in the Picual variety is similar to that of shaded leaves, and in the Arbequina variety is similar to that of sun leaves.