The Stress Effects of Difenoconazole and Chiral Difenoconazole-alcohol on Selenastrum capricornutum
This study evaluated the biological toxicity of difenoconazole and its degradation product difenocon-azole-alcohol to Selenastrum capricornutum by measuring median effective concentration(EC50),photosynthetic pigment levels,malondialdehyde(MDA)content,and antioxidant enzyme activity,with a focus on analyzing the stereoselective differences in chiral difenoconazole-alcohol's biological toxicity to algae.The EC50 values of difeno-conazole and difenoconazole-alcohol after 96 hours exposure were 0.67 mg·L-1 and 1.74 mg·L-1,respectively.The EC50 values of R-(+)-difenoconazole-alcohol and S-(-)-difenoconazole-alcohol after 96 hours exposure were 2.74 mg·L-1 and 1.68 mg·L-1,respectively.At the same time,based on the evaluation of changing the trend of oxida-tive damage-related parameters the levels of chlorophyll content of photosynthesis carriers as the algae was subjec-ted to exposure stress by difenoconazole,difenoconazole-alcohol,and difenoconazole-alcohol enantiomer,it was concluded that difenoconazole was more toxic to Selenastrum capricornutum than difenoconazole-alcohol,and the toxicity of chiral difenoconazole-alcohol was regarded as S-(-)-enantiomer＞racemate＞R-(+)-enantiomer.
万方数据
维普
