Enzyme activities regulating ROS metabolism in olive (Olea europaea L.) seeds

Abstract

Enzyme activities regulating ROS metabolism in the olive seeds are relatively unknown, in spite of the economical importance of this tree and the increasing interest of these seeds for multiple purposes. The aim of this work was to provide a comprehensive analysis of the genes encoding major antioxidant enzymes in mature seed. For this purpose, we have used transcriptomic sequence information available through our own experiments and in specific databases (Olea EST). Numerous sequences have been retrieved and analysed by using basic descriptive tools. Expression of transcripts encoding several of these enzymes has been carried out. These include catalases, superoxide dismutase, dehydroascorbate reductase, GSNO reductase, NADPH oxidase, lipoxygenase and thioredoxins. Cellular localization of several of these enzymes and histochemical detection of enzyme activities have been also carried out. We discuss how these enzyme activities may be involved in the olive seed metabolism through germination, and how they may contribute to the antioxidant capacity, stability and organoleptic properties of olive oils.