Degradation of pendimethalin by the yeast YC2 and determination of its two main metabolites

Abstract

In this study, we isolated a yeast strain, YC2, by enrichment culture from pendimethalin-contaminated soil. The analysis of its phenotypic features and 26S rRNA sequence confirmed that the strain YC2 is <i>Clavispora lusitaniae</i>. According to the kinetics of pendimethalin degradation, YC2 could degrade 74% of 200 mg L^-1 pendimethalin in CMB liquid culture over 8 days. LC-MS/MS was used to identify the metabolites of pendimethalin after degradation. This study confirmed that its metabolites consist of 1,2-dimethyl-3,5-dinitro-4-<i>N</i>(buta-1,3-dien-2-yl)-dinitrobenzenamine-<i>N</i>-oxide and 1,2-dimethyl-3,5-dinitro-4-<i>N</i>(prop-1-en-2-yl)-dinitrobenzenamine-<i>N</i>-oxide, which were broken down by a series of enzymatic reactions to produce CO₂ and H₂O. Thus, the study herein sheds light on the role of yeast in the degradation of pendimethalin.