Mechanistic insights into the delayed yellowing of broccoli by the combination of ectoine and lactide peptide

Preventing the postharvest yellowing of broccoli florets is a significant challenge. Our study investigated the effect of a combined treatment of ectoine and lactide peptide (ELP, soak treatment for 10 min) on the postharvest physiology and yellowing of broccoli. The treatment effectively reduced yellowing of the broccoli and inhibited the loss of nutrients. Transcriptomic and metabolomic analyses showed that the treatment with ectoine and lactide peptides reduced the accumulation of linoleic acid by downregulating the expression of LOX2 and EPHX2. Up-regulated the expression of HIS4 and down-regulated the expression of P4HA and PAO3, thereby synergistically promoting the accumulation of histidine and proline. Regarding flavonoid biosynthesis, CHS was upregulated and caffeoylquinic acid exhibited increased abundance. Results of the study enhance our understanding of the molecular mechanisms underlying the regulation of broccoli yellowing and demonstrate the potential use of a combined ectoine and lactide peptide treatment for the postharvest preservation of vegetables.