info:eu-repo/semantics/article
Harvesting at different time-points of day affects glucosinolate metabolism during postharvest storage of broccoli
Fecha
2020-10Registro en:
Casajús, Victoria; Demkura, Patricia Vérónica; Civello, Pedro Marcos; Gómez Lobato, María Eugenia; Martinez, Gustavo Adolfo; Harvesting at different time-points of day affects glucosinolate metabolism during postharvest storage of broccoli; Elsevier; Food Research International; 136; 10-2020; 1-10
0963-9969
CONICET Digital
CONICET
Autor
Casajús, Victoria
Demkura, Patricia Vérónica
Civello, Pedro Marcos
Gómez Lobato, María Eugenia
Martinez, Gustavo Adolfo
Resumen
The consumption of broccoli provides a large quantity of compounds with nutraceutical properties to the human diet. Broccoli has a high content of glucosinolates, compounds of the specialized metabolism with anticarcinogenic activity. In a previous work, we found that harvesting different time-points during the day affects the rate of senescence of broccoli heads during postharvest storage. In this work, we tested the same cultural practice to evaluate glucosinolate content and expression of genes involved in glucosinolate metabolism. Broccoli heads were harvested at 8:00, 13:00 and 18:00 h and stored for 5 d at 20 °C in darkness. We found that content and composition of the glucosinolate pool was affected by the time of harvest. Levels of indolic glucosinolates decreased with the time of harvest on the day whereas indolic glucosinolate showed only a moderate decrease. The expression of genes associated to the biosynthesis of aliphatic glucosinolates was variable during the day. In relation to indolic glucosinolates, an increase in the expression of the transcription factor BolMYB51 was detected around 13:00 h, which strongly correlated with the increase in expression of genes associated to their biosynthesis towards the end of the day. During postharvest, the storage in darkness affected differently the metabolisms of indolic and aliphatic glucosinolates. The content of aliphatics decreased during the postharvest period, as well as the expression of the genes associated with their biosynthesis. In contrast, in the case of indolics, their content remained constant or varied slightly, while the expression of the associated biosynthetic genes decreased only slightly. Finally, the genes related to the degradation of glucosinolates appeared to be strongly regulated by light conditions, since their expression increased during the course of the day and decreased markedly during postharvest storage in darkness. These results suggest that harvesting of broccolis close to noon would be convenient to maintain higher levels of glucosinolates during postharvest storage.