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，利用适合采后阶段应用的激素剂量的非生物胁迫，增强新鲜水果和蔬菜中促进健康（营养）和保护植物（植物抗毒素）的次级代谢产物。鉴于植物产生次级代谢物作为对抗压力的武器，可以很好地调整反应，以在增强提供植物保护和健康益处的膳食植物化学物质与通过将其暴露于受控剂量的压力源来使产品可接受性之间实现平衡。这将需要更好地了解压力源和次级代谢物之间的联系，并了解压力诱导的次级代谢物和代谢途径的改变。因此，我们在短期到中期的努力将集中在获得激素剂量的非生物应激源，信号成分和次级代谢产物的生产之间的联系的理解。研究涉及：（1）确定所选作物中非生物胁迫的激素剂量;（2）选择能有效诱导或增强所需次级代谢物而不影响产品感官质量的激素胁迫;（3）表征所选作物中产生氧化还原和激素信号的所选非生物胁迫及其组合;（4）在暴露于所选胁迫及其组合的作物中产生所需植物化学物质的途径的次级代谢物的概况分析;以及（5）建立信号成分与次生代谢物之间的相关关系，这将有助于识别关键信号成分。影响所需植物化学物质的生产。将用胡萝卜根和番茄果实进行研究。富含植物化学物质的新鲜水果和蔬菜最近被确定为一类新的功能性食品。保存具有增强的健康促进和抗病属性的新鲜作物不仅有助于新鲜农产品行业减少收获后的损失，还有助于确保人口健康。

Our long-term goal is to develop post-harvest conditioning technologies to enhance health-promoting (nutraceutical) and plant-protecting (phytoalexin) secondary metabolites in fresh fruits and vegetables using hormetic 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 dietary phytochemicals that offer plant protection and health benefits and acceptability of the produce by exposing them to controlled doses of stressors. This would require a better understanding of the link between stressors and secondary metabolites, and an understanding of the stress-induced alterations in the secondary metabolites and metabolic pathways. Thus our efforts in the short- to medium-term will be focused on gaining an understanding of the connections between hormetic doses of abiotic stressors, signal components and secondary metabolite production. The research involves: (1) the determination of hormetic doses of abiotic stresses in selected crops; (2) the selection of hormetic stresses which are effective in inducing or enhancing desired secondary metabolites without affecting sensory quality of the produce; (3) the characterization of the selected abiotic stresses and their combinations for their generation of redox and hormonal signals in the selected crops; (4) the profiling of secondary metabolites of the pathways that produce the desired phytochemicals in the crops exposed to the selected stresses and their combinations; and (5) the establishment of correlative relationships between signal components and secondary metabolites which will help identify key signal component(s) that impact the production of desired phytochemicals. Studies will be performed with carrot root and tomato fruit. Phytochemical-enriched fresh fruits and vegetables have recently been identified as a new class of functional foods. Preservation of fresh crops with enhanced attributes of health-promotion and disease resistance will not only help the fresh produce industry to reduce postharvest losses, but also help them to ensure a healthier population.