Varying concentrations of ethephon induce antioxidant defences and cell wall degradation to regulate storage quality of fresh-cut lotus root

Abstract

This study examined the impact of varying concentrations of ethephon (ET) immersion on the storage quality of fresh-cut lotus root. Compared to the 0.1%, the 0.8% and 1.6% ET groups inhibited phenolic oxidation and showed stronger antioxidant and reactive oxygen species balancing capacity during early storage, which led to better browning inhibition. During the early storage period, varying concentrations of ET treatments were inversely associated with microbial growth, and Pseudomonas as the major microorganism was significantly inhibited. During the post-storage period, the ET group exacerbated cell wall metabolism, contributed to the softening of lotus root slices. Additionally, ET stimulated enhanced respiration and reduced total soluble solids content as ET concentration increased. The heightened expression of NnERF in the late storage stage suggested a potential link to the regulation of root quality deterioration. Both browning inhibition and quality deterioration promotion exhibited gradient shifts in accordance with ET concentration. Combined with DNA affinity purification sequencing technology to identify the presence of motifs that bind specifically to ERF1B in lotus root, and screening for the possible target genes NnPL18 and NnACO that may be regulated by NnERF1B-like (104610030), it further suggests that NnERF1B-like (104610030) may mediate the process of lotus root flake softening and ethylene biosynthesis.