木质素降解酶在不同堆肥基质中的吸附传输特性研究

Research on Sorption and Transport Characteristics of Ligninolytic Enzymes in Different Compost Substances

为了深入探究木质素降解酶在不同堆肥基质中的吸附传输特性,通过批量实验对比了土壤、菜叶、稻草和米糠对木质素降解酶的吸附性能,并进行了动力学分析和等温吸附模型拟合,同时通过柱淋洗实验考察了木质素降解酶在4种堆肥基质中的迁移传输特性.结果表明,堆肥基质对木质素降解酶的吸附与基质种类有关,土壤、菜叶、稻草和米糠对木素过氧化物酶(LiP)和锰过氧化物酶(MnP)的吸附量分别为1.22、1.27、1.13、1.22U·g-1和5.09、4.88、4.43、3.95U·g-1.比较LiP和MnP吸附的动力学模型,准二级动力学方程为表征木质素降解酶吸附的最佳模型,其R2值为0.9732～0.9997,Elovich方程拟合较差,准一级动力学方程拟合最差;Langmuir模型对等温吸附数据进行拟合效果最好,而实验数据不适合用Freundlich方程表征.土壤、菜叶、稻草和米糠对LiP和MnP饱和吸附容量分别为1.23、1.30、1.17、1.14U·g-1和5.70、5.19、4.73、4.14U·g-1.LiP和MnP在稻草和米糠基质中传输效果较好,可传输到最深层10mL处,而在土壤和菜叶基质中则被滞留在浅层.

To understand the characteristics of ligninolytic enzymes sorption and transport in different compost substances,ligninolytic enzymes adsorption on soil,vegetable leaf,rice straw and chaff was comparatively studied through batch jar tests and relevant kinetics and isotherm equilibrium were discussed as well as a column experiment was performed to study the process of transport.The results showed that the sorption efficiency was depended on the sorts of substances.The adsorptive capacities of soil,vegetable leaf,rice straw and chaff to lignin peroxidase（LiP） were 1.22 U·g-1,1.27 U·g-1,1.13 U·g-1,1.22 U·g-1 and to manganese peroxidase（MnP） were 5.09 U·g-1,4.88 U·g-1,4.43 U·g-1,3.95 U·g-1,respectively.Comparing the kinetic models of LiP and MnP adsorption,the pseudo-second-order reaction model（R2 0.973-0.999 7） was the best of the models.Elovich equation was a bit better than pseudo-first-order kinetic which was the worst.The equilibrium data could be fitted well with Langmuir model while it could not satisfied with Freundlich model.The adsorptive saturation of soil,vegetable leaf,rice straw and chaff to LiP were 1.23 U·g-1,1.30 U·g-1,1.17 U·g-1,1.14 U·g-1 and to MnP were 5.70 U·g-1,5.19 U·g-1,4.73 U·g-1,4.14 U·g-1.LiP and MnP had good transport capability in straw and chaff to move to the deepest layer of 10 mL while remained in the superficial layers in soil and vegetable leaf.