Change in the expression of anthocyanin pathway genes in developing inflorescences of sicilian landraces of pigmented broccoli and cauliflower

Plant-based foods contain significant amount of bioactive compounds which often provide both basic nutrition and desirable health benefits. In the last decades, special attention has been paid towards Brassicaceae edible plants due to their richness in secondary metabolites functioning as antioxidants. Among them, colored cauliflower and cabbage are very eye-catching, commercially available vegetables characterized by the presence of high levels of anthocyanin pigments fulfilling important protective role against biotic and abiotic stresses in plants, and, endowed of potent nutritional and healthy properties as component of the human diet. In this respect, the consumption of pigmented Brassica genotypes has been strictly related to the reduction of the risk of certain chronic diseases including cardiovascular diseases and cancer. The anthocyanin biosynthesis pathway has been elucidated in many herbaceous and tree plants and most of the structural gene encoding the enzymes responsible for each steps have been isolated from Brassica genus. In this study, we monitored the expression pattern of three structural genes involved in anthocyanin biosynthetic pathway: PAL (phenylalanine ammonia lyase), DFR (dihydroflavonol-4- reductase) and GST (glutathione S-transferase) during four weeks of field growth of different Brassica crops; the anthocyanin content was also measured in order to correlate gene expression with pigment accumulation. The results reveal that the induction of gene expression simultaneously occurs or slightly precedes the maximum levels of anthocyanin accumulation.