Insights on diverse roles of glutathione metabolism in regulating the browning of fresh-cut produce

The postharvest preservation of fresh-cut produce remains a major challenge, largely due to wound-induced enzymatic browning. Historically, research in this area has focused primarily on oxidase-mediated pathways. Glutathione (GSH), a non-protein tripeptide thiol widely distributed across the plant kingdom, has traditionally been viewed merely as a sacrificial chemical antioxidant that mitigates browning. In this mini-review, we discuss the multi-tiered defense system governed by GSH metabolism in regulating the browning of fresh-cut produce. Based on existing evidence, we propose that GSH is not merely a passive reactive oxygen species scavenger. Instead, it may serve as a homeostatic orchestrator through multiple layers of regulation, including PPO inhibition, redox signaling, energy metabolism, and secondary metabolite allocation. Due to limited literature regarding GSH metabolism in fresh-cut produce, some of these intricate mechanisms are currently inferred from model plant systems, such as Arabidopsis thaliana . More direct evidence is required in diverse fresh-cut horticultural products. In all, a deeper understanding of these multifaceted roles of GSH metabolism in enzymatic browning will provide fresh insights into the development of targeted anti-browning strategies in the fresh-cut industry.