Azacytidine shows potential in controlling the chilling injury of banana peel during cold storage

Abstract

Banana suffers from chilling injury at low temperatures, which significantly challenges industrial banana quality control worldwide without a widely-accepted solution, to date. In this study, 5-azacytidine (5-azaC), a common DNA methylation inhibitor (DNA methylation is a conserved modification that regulates physiological processes), was used to treat banana fingers with subsequent storage at 7 °C for 9 days, which can be a novel strategy for controlling banana peel chilling injury and quality deterioration. In most sampling days, 5-azaC treatment significantly increased lightness value (L*), hue angle, and firmness while significantly decreased the browning index. Surprisingly, the chilling injury index was persistently declined by 5-azaC up to 26.8 % (p < 0.05). 5-azaC also reduced electrolyte leakage and levels of malondialdehyde and reactive oxygen species, indicating the control of chilling injury development. Further results showed that 5-azaC-inhibited DNA methylation contributed to banana chilling injury control by modulating the redox system and energy homeostasis. Collectively, this study offered new insights into fruit chilling injury development and control, as well as inspired potential strategies for postharvest quality control.