The roles of Salvia miltiorrhiza-derived carbon dots involving in maintaining quality by delaying senescence of postharvest flowering Chinese cabbage

Abstract

Salvia miltiorrhiza-derived carbon dots (SmCDs), as a new type of nanomaterial, play vital roles in plant growth, antioxidation and abiotic stress alleviation. Flowering Chinese cabbage is prone to wilt and yellowing after harvest. However, the roles of SmCDs in delaying senescence of postharvest flowering Chinese cabbage to maintain quality remain unclear. Herein, we found that SmCDs had effective impacts on anti-aging, enhancing maximal fluorescence ratio, procrastinating chlorophyll degradation, sustaining reactive oxygen species (ROS) metabolism homeostasis, and improving the contents of vitamin C, sucrose, soluble sugar, and flavonoid. Moreover, SmCDs suppressed the expressions of chlorophyll degradation genes (BrNYE1, BrNYC1, BrNOL, BrPPH, and BrPAO), senescence marker gene (BrSAG12), and respiratory burst oxidase homologs genes (BrRBohA, BrRBohB, BrRBohD, and BrRBohF), while SmCDs promoted the flavonoid biosynthesis genes (BrFLS3, BrFLS1, BrC4H, and BrCHI) expression. Interestingly, sucrose synthase, neutral invertase, and acid invertase might be the pivotal enzymes to restrict sugar accumulation under SmCDs treatment.

Keywords: Antioxidant metabolism; Flowering Chinese cabbage; Postharvest quality; Salvia miltiorrhiza-derived carbon dots; Sugar metabolism.