Enhancement of health-promoting and plant-protecting secondary metabolites by postharvest conditioning with hormetic doses of abiotic stresses

我们的长期目标是开发采后调理技术，通过提高促进健康和保护植物的次生代谢物来保持新鲜水果和蔬菜的质量，使用适合于采后阶段应用的刺激或有益剂量的非生物胁迫。考虑到植物产生次生代谢物作为对抗逆境的武器，通过将它们暴露在受控剂量的应激源中，可以很好地调整这种反应，以在增强所需的植物化学物质和产品的可接受性之间实现平衡。我们在短期和中期的努力将集中在了解激素应激源和新鲜农产品中次生代谢物产生之间的联系，以及了解应激诱导的代谢途径的变化。展望未来，这项研究将涉及：(1)在所选择的新鲜农产品中有效地诱导或增强靶向(或所需)次生代谢物的非生物逆境的鉴定；(2)所选的霍尔蒙逆境在胁迫组织中产生信号成分和随后的合成能力的特征；(3)在暴露于逆境及其组合的作物中产生所需植物化学物质的初级代谢物和次生代谢物的特征；(4)阐明信号成分、合成能力状态和应激组织中次生代谢物之间的关系；以及(5)评价初级和次级代谢途径的改变。研究将对胡萝卜根、西兰花和西红柿水果进行。从这项研究中获得的知识将提供工具，通过知情选择应激或联合应激来开发采后调节方案，以实现所需次生代谢物的增强产生。富含植物化学物质的新鲜水果和蔬菜被认为是一类新的功能食品。保存具有增强的健康益处和抗病属性的新鲜作物，不仅有助于生鲜农产品行业减少收获后的损失，还有助于确保更健康的人口。********

Our long-term goal is to develop post-harvest conditioning technologies to preserve the quality of fresh fruits and vegetables with enhancement in health-promoting and plant-protecting secondary metabolites using hormetic or beneficial doses of abiotic stresses that are suitable for application in the postharvest phase. Given that plants produce secondary metabolites as weapons to combat stresses, it is possible that the response can well be tuned to achieve a balance between enhancement of desirable phytochemicals and acceptability of the produce by exposing them to controlled doses of the stressors. Our efforts in the short- to medium-term will be focused on gaining an understanding of the connections between hormetic stressors and secondary metabolite production in fresh produce, and an understanding of the stress-induced alterations in the metabolic pathways. Going forward, the research would involve: (1) the identification of hormetic abiotic stresses that are effective in inducing or enhancing targeted (or desired) secondary metabolites in selected fresh produce; (2) the characterization of the selected hormetic stresses for their generation of signal components and the consequent synthetic capacity in the stressed tissues; (3) the profiling of primary metabolites, and secondary metabolites of the pathways that produce the desired phytochemicals in the crops exposed to the stresses and their combinations; (4) the elucidation of the relationships between signal components, synthetic capacity status, and secondary metabolites in the stressed tissues; and (5) the evaluation of alterations in the primary, and the secondary metabolic pathways. Studies will be performed with carrot root, broccoli and tomato fruit. The knowledge gained from this research will provide the tools to develop postharvest conditioning protocols by informed selection of hormetic stresses or a combination of stresses to achieve enhanced production of desired secondary metabolites. Phytochemical-enriched fresh fruits and vegetables are considered as a new class of functional foods. Preservation of fresh crops with enhanced attributes of health benefits and disease resistance will not only help the fresh produce industry to reduce postharvest losses, but also help them to ensure a healthier population. ********