title: Inhibitory effects of ionic liquids on the lactic dehydrogenase activity.
abstract: Ionic liquids (ILs) were widely used in scientific and industrial application and have been reported to possess potential toxicity to the environment and human health. The effects of six typical N-methylimidazolium-based ILs ([Cnmim]X, n=4, 6, 8; X=Br(-), Cl(-), BF4(-), CF3SO3(-)) on the lactic dehydrogenase (LDH) activity and the molecular interaction mechanism of ILs and the LDH were investigated with the aid of spectroscopic techniques. Experimental results showed that the LDH activity was inhibited in the presence of ILs. For the ILs with the same anion but different cations, their inhibitory ability on the LDH activity increased with increasing the alkyl chain length on the IL cation. Thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS) were obtained by analyzing the fluorescence behavior of LDH with the addition of ILs. Both positive ΔH and ΔS suggested that hydrophobicity was the major driven force in the interaction process as expected.
authors.affiliation: College of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454003, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Dong
authors.affiliation: College of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454003, China. Electronic address: fanyunchang@hpu.edu.cn.
authors.forename: Yunchang
authors.initials: Y
authors.lastname: Fan
authors.affiliation: College of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454003, China.
authors.forename: Heng
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Technology Center of Ningbo Entry-Exit Inspection and Quarantine Bureau, Ningbo 315012, China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Zhong
authors.affiliation: College of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454003, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: College of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454003, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Miao
authors.affiliation: College of Physics and Chemistry, Henan Polytechnic University, Jiaozuo 454003, China.
authors.forename: Shaofeng
authors.initials: S
authors.lastname: Hua
mesh_terms: D004791:Enzyme Inhibitors / Q000494:pharmacology*; D057927:Hydrophobic and Hydrophilic Interactions; D052578:Ionic Liquids / Q000494:pharmacology*; D045022:Lactate Dehydrogenases / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation; D013816:Thermodynamics
chemical_list: D004791:Enzyme Inhibitors; D052578:Ionic Liquids; D045022:Lactate Dehydrogenases
keywords: Hydrophobicity; Ionic liquids (ILs); Lactic dehydrogenase