کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4979682 1453034 2017 40 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Kinetics of soil dehydrogenase in response to exogenous Cd toxicity
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بهداشت و امنیت شیمی
پیش نمایش صفحه اول مقاله
Kinetics of soil dehydrogenase in response to exogenous Cd toxicity
چکیده انگلیسی
Soil dehydrogenase plays a role in the biological oxidation of soil organic matter and can be considered a good measure of the change of microbial oxidative activity under environmental pollutions. However, the kinetic characteristic of soil dehydrogenase under heavy metal stresses has not been investigated thoroughly. In this study, we characterized the kinetic characteristic of soil dehydrogenase in 14 soil types, and investigated how kinetic parameters changed under spiked with different concentrations of cadmium (Cd). The results showed that the Km and Vmax values of soil dehydrogenase was among 1.4-7.3 mM and 15.9-235.2 μM h−1 in uncontaminated soils, respectively. In latosolic red soil and brown soil, the inhibitory kinetic mechanism of Cd to soil dehydrogenase was anticompetitive inhibition with inhibition constants (Ki) of 12 and 4.7 mM, respectively; in other soils belonged to linear mixed inhibition, the values of Ki were between 0.7-4.2 mM. Soil total organic carbon and Ki were the major factors affecting the toxicity of Cd to dehydrogenase activity. In addition, the velocity constant (k) was more sensitive to Cd contamination compared to Vmax and Km, which was established as an early indicator of gross changes in soil microbial oxidative activity caused by Cd contamination.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Hazardous Materials - Volume 329, 5 May 2017, Pages 299-309
نویسندگان
, , , , , , , ,