Comparative transcriptome and metabolome analyses reveal the mechanism of slightly acidic electrolyzed water in delaying browning and senescence in rambutan fruit

Postharvest pericarp browning and rapid senescence pose major challenges for the commercialization of rambutan fruit. In this study, the efficacy of slightly acidic electrolyzed water (SAEW), a non-residual and non-toxic preservation agent, in delaying rambutan fruit senescence and maintaining quality, was examined through integrated physiological, transcriptomic and metabolomic analyses. Physiological results demonstrated that SAEW delayed the degradation of pericarp browning and redness while mitigating oxidative stress-induced membrane system damage. Integrated transcriptomic–metabolomic profiling revealed that SAEW upregulated genes linked to transcriptional–translational processes, antioxidant system and biosynthetic pathways of anthocyanins, arginine and proline, maintaining cellular redox homeostasis and increasing the accumulation of anti-senescence metabolites (ascorbic acid, anthocyanins, proline, ornithine, arginine, GABA and spermidine). Through systematic analysis of transcription factor binding sites and cis-regulatory elements, we established a comprehensive regulatory network of transcription factors governing the anti-senescence in response to SAEW. The results suggest that application of SAEW could be a potential strategy to preserve the postharvest quality in rambutan fruit.