有机溶剂中尼龙布固定化木瓜蛋白酶动力学性能研究

Kinetic Characteristics of Immobilized Papain from Neilon Cloth in Organic Solvents

利用尼龙布固定化木瓜蛋白酶,在14种有机溶剂的不同浓度(10%,20%)中,以酪蛋白为底物,于温水浴中反应,在275nm中测定其OD值变化,通过一定的数量关系转化成MichaeLis-Menten公式,求出K m与v max参数。结果表明,酶活性在有机介质中有一定的变化,其中20%乙酸乙酯、10%和20%的丁醇、20%的戊醇对酶与底物的结合有促进作用,而其他的有机溶剂环境则表现削弱作用。在乙醇、甲醇、1,4-二氧六环、四氢呋喃、二甲基亚砜、环己环的反应环境中,酶与底物的亲和力随着有机溶剂浓度的升高而下降,最大反应速度上升;在正丙醇、乙腈、乙酸乙酯、丁醇、戊醇、己醇、苯、正十二醇的反应环境中,酶与底物的亲和力随着有机溶剂浓度的升高而升高,最大反应速度下降。

In this experiment,papain was immobilized with nylon cloth.In 14 kinds of organic solvents(10%,20%),casein was used as the substrate to react in a warm water bath.The change of OD value was determined in 275nm.The parameters of Km and vmax were obtained through a certain quantitative relationship into MichaeLis-Menten.The results showed that the enzyme activity had some changes in the organic medium,in which 20%ethyl acetate,10%and 20%butanol,20%pentyl alcohol promoted the binding of the enzyme to the substrate,while the other organic solvent environment weakened.In the reaction environment of hexanol,methanol,1,4-dioxane,tetrahydrofuran,dimethyl sulfoxide,and cyclohexane,the affinity of enzyme and substrate decreased with the increase of organic solvent concentration,the maximum reaction rate increased,and the reaction in n-propanol,acetonitrile,ethyl acetate,butanol,pentanol,hexanol,benzene,and positive twelve alcohol In the environment,the affinity of enzyme and substrate increased with the increase of organic solvent concentration,and the maximum reaction rate decreased.