Dorado-Martínez Adriana, Ruiz-Ordaz Nora, Galíndez-Mayer Juvencio, Santoyo-Tepole Fortunata, Ramos-Monroy Oswaldo
Instituto Politécnico Nacional Escuela Nacional de Ciencias Biológicas Mexico City Mexico.
Eng Life Sci. 2017 Jul 26;17(10):1088-1096. doi: 10.1002/elsc.201700060. eCollection 2017 Oct.
The successive application of distinct pesticides, or mixtures of them, is a frequent practice that could adversely affect the microbial species inhabiting soil and aquatic ecosystems. The ability of soil or aquatic microbiota to degrade a pesticide could be affected by the presence of another. If the degradation rate of the first compound is inhibited, its dissipation half-life in the environment could be hazardously enlarged. Few studies have been made to quantify the impact on the biodegradation rate of pesticides in soils or water by the presence of other pesticides. In this work, a method for assessing the effect of a pesticide on the biodegradation rate of another, measuring its effect on the biodegradation kinetics of a single bacterial strain is presented. The mathematical analysis is a powerful tool to study the stoichiometry and kinetics of microbial processes, which was used to evaluate independently, in detail, the effect of three pesticides (propanil, linuron, and dicamba) on the biodegradation kinetics of 2,4-dichlorophenoxyacetic acid by a strain of sp. It was evidenced that linuron and dicamba caused a decay of more than 40% in the top instantaneous degradation rate of 2,4-dichlorophenoxyacetic acid, while propanil showed a minimal effect.
连续施用不同的农药或其混合物是一种常见做法，这可能会对栖息在土壤和水生生态系统中的微生物物种产生不利影响。土壤或水生微生物群降解一种农药的能力可能会受到另一种农药存在的影响。如果第一种化合物的降解速率受到抑制，那么它在环境中的消散半衰期可能会危险地延长。很少有研究对其他农药的存在对土壤或水中农药生物降解速率的影响进行量化。在这项工作中，提出了一种评估一种农药对另一种农药生物降解速率的影响的方法，即测量其对单一细菌菌株生物降解动力学的影响。数学分析是研究微生物过程化学计量学和动力学的有力工具，该工具被用于详细独立评估三种农药（敌稗、利谷隆和麦草畏）对一株 sp. 菌株降解 2,4-二氯苯氧乙酸生物降解动力学的影响。结果表明，利谷隆和麦草畏使 2,4-二氯苯氧乙酸的最高瞬时降解速率下降了 40% 以上，而敌稗的影响最小。
