Centro de Biología Molecular Vegetal, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago 7800024, Chile.
Int J Mol Sci. 2022 May 13;23(10):5438. doi: 10.3390/ijms23105438.
Several metals belong to a group of non-biodegradable inorganic constituents that, at low concentrations, play fundamental roles as essential micronutrients for the growth and development of plants. However, in high concentrations they can have toxic and/or mutagenic effects, which can be counteracted by natural chemical compounds called chelators. Chelators have a diversity of chemical structures; many are organic acids, including carboxylic acids and cyclic phenolic acids. The exogenous application of such compounds is a non-genetic approach, which is proving to be a successful strategy to reduce damage caused by heavy metal toxicity. In this review, we will present the latest literature on the exogenous addition of both carboxylic acids, including the Kreb's Cycle intermediates citric and malic acid, as well as oxalic acid, lipoic acid, and phenolic acids (gallic and caffeic acid). The use of two non-traditional organic acids, the phytohormones jasmonic and salicylic acids, is also discussed. We place particular emphasis on physiological and molecular responses, and their impact in increasing heavy metal tolerance, especially in crop species.
几种金属属于一组不可生物降解的无机成分，这些金属在低浓度时，作为植物生长和发育所必需的微量营养素，起着至关重要的作用。然而，在高浓度时，它们可能具有毒性和/或致突变性，而这些影响可以通过被称为螯合剂的天然化学化合物来抵消。螯合剂具有多种化学结构；其中许多是有机酸，包括羧酸和环状酚酸。这些化合物的外源应用是非遗传方法，事实证明，这是一种减少重金属毒性造成的损害的成功策略。在这篇综述中，我们将介绍最新的关于外源添加羧酸（包括克雷布斯循环中间体柠檬酸和苹果酸，以及草酸、硫辛酸和酚酸（没食子酸和咖啡酸）的文献。我们还讨论了两种非传统有机酸，植物激素茉莉酸和水杨酸的应用。我们特别强调了生理和分子反应，以及它们在提高重金属耐受性方面的影响，特别是在作物物种中。
