Insights into profiling of glucosinolates and genes involved in its metabolic pathway accompanying post-harvest yellowing of broccoli

Abstract Postharvest yellowing is the main manifestation in the rapid deterioration of broccoli. Here, we monitored the composition and content changes of glucosinolates accompanying the yellowing process of broccoli to reveal the changes of characteristic bioactive substances along with the appearance changes process. Glucosinolates content was greatly reduced in parallel with the yellowing process. The most prominent reduction was among glucoraphanin and its hydrolysate sulforaphane that decreased by 37 % and 69 %, respectively, during slight yellowing, and up to 85 % and 93 %, respectively when severely yellowed. Among the genes involved in glucoraphanin metabolism pathway, the continuous down-regulation of BoCYP83A1, BoTGG1 and BoTGG2 genes had the most serious impact on the reduction of glucoraphanin and sulforaphane content. Postharvest yellowing influenced the appearance of broccoli commodity, while greatly reduced the nutritional value.