Transcriptomic and physiological analysis reveal the effects and potential mechanisms of low-voltage electrostatic field treatment on the quality retention of goji berries during storage

The lack of effective quality maintenance technology is the main issue in the storage and preservation of goji berry. This study was conducted on the physiological indicators, metabolism of reactive oxygen species and mitochondrial redox processes of goji berry over a 15-day storage period to evaluate the impact of a low-voltage electrostatic field (LVEF) on their postharvest quality. Analysis of the transcriptome showed that LVEF resulted in higher expression of genes linked to reactive oxygen species and mitochondrial redox metabolism, while inhibiting the transcription of genes linked to cell wall metabolism and the ethylene biosynthesis and signaling pathway in goji berry. Moreover, LVEF prevented an increase in conductivity and the peroxidation of membrane lipids, while reducing the production rate of superoxide anion O₂^•- (126.7 mmol min⁻¹ g⁻¹) and H₂O₂ (0.75 μmol g⁻¹) levels. LVEF treatment significantly enhanced superoxide dismutase (SOD) (1.12-fold), catalase (CAT) (1.37-fold), peroxidase (POD) (1.58-fold), ascorbate peroxidase (APX) (1.02-fold), and glutathione reductase (GR) activity. In addition, LVEF increased the mitochondrial NAD(P)⁺ levels, decreased the NAD(P)H levels, and increased the NAD(P)⁺/NAD(P)H ratio. The study suggested that the post-harvest storage quality of goji berries can be improved via LVEF, which achieves this by regulating ROS metabolism and mitochondrial redox metabolism.