Stability of Coumarins and Determination of the Net Iron Oxidation State of Iron-Coumarin Complexes: Implications for Examining Plant Iron Acquisition Mechanisms.

ABSTRACT: Coumarins are exuded into the soil environment by plant roots in response to iron (Fe) deficiency. Previous studies have shown that coumarins can increase the Fe solubility upon interaction with sparsely soluble Fe(III) (hydr)oxide. However, the chemical mechanisms of Fe(III) (hydr)oxide dissolution by coumarins remain unclear. The high redox instability of dissolved coumarins and the interference of coumarins in determining the Fe redox state hinder the quantitative and mechanistic investigation of coumarin-induced Fe mobilization. In this study, we investigated the oxidative stability of three coumarins that have been found in root exudates, esculetin, scopoletin, and fraxetin, over a broad pH range under oxic and anoxic conditions. Our results show that the oxidation of coumarins is irr

SUBMITTER: Kang K 

PROVIDER: S-EPMC10749481 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature