Department for Sustainable Food Process, Università Cattolica del Sacro Cuore, 29122, Piacenza, Italy.
Department of Biology, Faculty of Science, Selcuk University, Selcuklu, 42130, Konya, Turkey.
Plant Physiol Biochem. 2024 Jun;211:108713. doi: 10.1016/j.plaphy.2024.108713. Epub 2024 May 8.
The spinach (S. oleracea L.) was used as a model plant to investigate As toxicity on physio-biochemical processes, exploring the potential mitigation effect of curcumin (Cur) applied exogenously at three concentrations (1, 10, and 20 μM Cur). The employment of Cur significantly mitigated As-induced stress in spinach photosynthetic performance (F/F, F/F, and F/F). Moreover, the co-incubation of Cur with As improved physiological processes mainly associated with plant water systems affected by As stress by recovering the leaf's relative water content (RWC) and osmotic potential (ψπ) nearly to the control level and increasing the transpiration rate (E; 39-59%), stomatal conductivity (g; 86-116%), and carbon assimilation rate (A; 84-121%) compared to As stressed plants. The beneficial effect of Cur in coping with As-induced stress was also assessed at the plant's oxidative level by reducing oxidative stress biomarkers (HO and MDA) and increasing non-enzymatic antioxidant capacity. Untargeted metabolomics analysis was adopted to investigate the main processes affected by As and Cur application. A multifactorial ANOVA discrimination model (AMOPLS-DA) and canonical correlation analysis (rCCA) were employed to identify relevant metabolic changes and biomarkers associated with Cur and As treatments. The results highlighted that Cur significantly determined the accumulation of glucosinolates, phenolic compounds, and an increase in glutathione redox cycle activities, suggesting an overall elicitation of plant secondary metabolisms. Specifically, the correlation analysis reported a strong and positive correlation between (+)-dihydrokaempferol, L-phenylalanine (precursor of phenolic compounds), and serotonin-related metabolites with antioxidant activities (ABTS and DPPH), suggesting the involvement of Cur application in promoting a cross-talk between ROS signaling and phytohormones, especially melatonin and serotonin, working coordinately to alleviate As-induced oxidative stress. The modulation of plant metabolism was also observed at the level of amino acids, fatty acids, and secondary metabolites synthesis, including N-containing compounds, terpenes, and phenylpropanoids to cooperate with As-induced stress response.
以菠菜（S. oleracea L.）为模式植物，研究砷毒性对生理生化过程的影响，探索外源姜黄素（Cur）在三个浓度（1、10 和 20 μM Cur）下的潜在缓解作用。Cur 的应用显著减轻了砷对菠菜光合作用性能（F/F、F/F 和 F/F）的胁迫。此外，Cur 与 As 共孵育通过恢复叶片相对含水量（RWC）和渗透势（ψπ）接近对照水平，以及增加蒸腾速率（E；39-59%）、气孔导度（g；86-116%）和碳同化率（A；84-121%），从而改善了主要与植物水分系统相关的生理过程，这些过程受到 As 胁迫的影响。与受 As 胁迫的植物相比，Cur 在应对 As 诱导的胁迫方面对植物的氧化水平也具有有益的影响，降低了氧化应激生物标志物（HO 和 MDA）并增加了非酶抗氧化能力。采用非靶向代谢组学分析来研究受 As 和 Cur 应用影响的主要过程。采用多因素方差分析判别模型（AMOPLS-DA）和典型相关分析（rCCA）来识别与 Cur 和 As 处理相关的相关代谢变化和生物标志物。结果表明，Cur 显著决定了硫代葡萄糖苷、酚类化合物的积累和谷胱甘肽氧化还原循环活性的增加，表明植物次生代谢物的整体诱导。具体而言，相关性分析报告了 (+)-山奈酚、L-苯丙氨酸（酚类化合物的前体）和与抗氧化活性（ABTS 和 DPPH）相关的血清素相关代谢物之间具有很强的正相关，表明 Cur 应用参与促进 ROS 信号转导和植物激素之间的交叉对话，特别是褪黑素和血清素，协同作用以减轻 As 诱导的氧化应激。还观察到植物代谢在氨基酸、脂肪酸和次生代谢物合成水平上的调节，包括含氮化合物、萜类化合物和苯丙烷类化合物，以与 As 诱导的应激反应协同作用。
