State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China.
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China.
Chemosphere. 2019 May;223:628-635. doi: 10.1016/j.chemosphere.2019.02.080. Epub 2019 Feb 15.
Quinones are components of electron transport chains in photosynthesis and respiration. Acetylacetone (AA), structurally similar to benzoquinone (BQ) for the presence of two identical carbonyl groups, has been reported as a quinone-like electron shuttle. Both BQ and AA are important chemicals in the aquatic environment. However, little information is known about their interactions if co-existed. We found here that AA significantly enhanced the conversion of BQ. By analyzing the evolution of chemical concentration, solution pH, dissolved oxygen, and the final products, the interactions between AA and BQ were elucidated. The reactions between BQ and AA generated oxygen but ultimately led to the reduction of solution pH and dissolved oxygen. The reactions proceeded faster under indoor lighting condition than in the dark. The formation of semiquinone radicals is believed as the primary step. The secondary AA-derived radicals might be strongly oxidative or reductive, depending on the concentration of dissolved oxygen. Insoluble humus was generated in the mixture of BQ and AA. These results suggest that the presence of AA might interfere with photosynthesis and respiration through the interactions with quinones.
醌类化合物是光合作用和呼吸作用中电子传递链的组成部分。乙酰丙酮（AA），由于存在两个相同的羰基基团，其结构与苯醌（BQ）相似，已被报道为一种类醌电子穿梭体。BQ 和 AA 都是水生环境中的重要化学物质。然而，如果它们共存，关于它们相互作用的信息知之甚少。我们在这里发现 AA 显著增强了 BQ 的转化。通过分析化学浓度、溶液 pH 值、溶解氧和最终产物的演变，阐明了 AA 和 BQ 之间的相互作用。BQ 和 AA 之间的反应会产生氧气，但最终会导致溶液 pH 值和溶解氧的降低。在室内光照条件下，反应速度比在黑暗中更快。半醌自由基的形成被认为是主要步骤。二次 AA 衍生的自由基可能具有很强的氧化性或还原性，具体取决于溶解氧的浓度。在 BQ 和 AA 的混合物中形成了不溶性腐殖质。这些结果表明，AA 的存在可能通过与醌类化合物的相互作用干扰光合作用和呼吸作用。
