Chlorophyll and carotenoid profile and enzymatic activities (chlorophyllase and lipoxygenase) in olive drupes from the fruit-setting period to harvest time

Abstract

The aim of this study was to monitor the pigment profile and chlorophyllase (Chlase) and lipoxygenase (Lox) activities of olive (Olea europaea L.) drupes during the development of the fruit from 'Arbequina' and 'Farga' in order to find better ways to characterize cultivars such as 'Arbequina' that produce virgin olive oils that are highly appreciated in international markets. 'Farga' was included as a comparative reference. The total pigment content in olive drupes from the two cultivars studied suffered a decrease when the maturation process began, the rate of chlorophyll degradation being more marked than that of the carotenoid pigment. Chlorophyllides a and b, cis-α-carotene, β-cryptoxanthin, and esterified xanthophylls were detected only in 'Arbequina' fruit. The behavior of the Chlase and Lox activities in both cultivars was different. Chlase activity in olives from 'Farga' was detected only at the end of the pit hardening period, but in the case of 'Arbequina' the presence of dephytilated chlorophyllic derivatives is directly related to a higher Chlase enzymatic activity than that of 'Farga' fruit. Although the level of these enzymatic activities decreased when ripening advanced in both cultivars, in 'Arbequina' both enzymes showed a slight increase of activity at the latest stages of ripening.