This study investigated if the use of the pesticides cyprodinil and fludioxonil produced an inhibitory effect on the bovine liver catalase (CAT) activity. It was documented that the activity of the enzyme decreased with increasing concentrations of cyprodinil and fludioxonil from 0 to 500 ppm. At pesticide concentrations of 250 and 500 ppm, the activity of CAT remained unchanged and passed to a steady state. The exposure to cyprodinil in concentrations of 10, 50, 100, 250 and 500 ppm, led to a decrease in the per cent of the CAT enzyme activity calculated as 45.4, 68.0, 73.0, 77.8 and 77.4, respectively. Similarly, the exposure to fludioxonil in concentrations of 10, 50, 100, 250 and 500 ppm, produced the following percentage decrease in the CAT enzyme activity: 20.0, 30.8, 42.8, 46.3 and 45.9, respectively. Cyprodinil inhibited CAT competitively, whereas the mechanism of fludioxonil inhibition over the enzyme was non-competitive.

中文翻译：

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嘧菌环胺和氟啶虫腈农药对牛肝过氧化氢酶活性的影响

本研究调查了杀虫剂嘧菌环胺和氟菌腈的使用是否对牛肝过氧化氢酶 (CAT) 活性产生抑制作用。据记载，随着嘧菌环胺和氟菌腈的浓度从 0 增加到 500 ppm，酶的活性降低。在 250 和 500 ppm 的农药浓度下，CAT 的活性保持不变并进入稳定状态。暴露于浓度为 10、50、100、250 和 500 ppm 的环丙嘧啶，导致 CAT 酶活性百分比下降，分别计算为 45.4、68.0、73.0、77.8 和 77.4。类似地，暴露于浓度为 10、50、100、250 和 500 ppm 的氟啶虫胺会导致 CAT 酶活性的降低百分比如下：分别为 20.0、30.8、42.8、46.3 和 45.9。Cyprodinil 竞争性抑制 CAT，