作　　者： ; ; ; ;

机构地区： 河南科技学院生命科技学院

出　　处： 《湖北农业科学》 2009年第10期2414-2417,共4页

摘　　要： 对筛选得到的一株黑曲霉菌株(Aspergillus niger inu-8)所产菊粉酶的酶学性质进行了研究。结果表明,菊粉酶的最适作用温度为45～55℃,在30～60℃范围内该酶能保持较高的活性,但超过60℃后其活性迅速下降;在80℃水浴下处理0.5 h,酶活性丧失80%;该酶的适宜pH值相对偏酸,在pH值4.0～6.0时有很好的稳定性,在pH值5.0时表现为一个活性高峰;Ca2+对该酶具有明显激活作用,Hg2+和EDTA(乙二胺四乙酸)是该酶的强烈抑制剂;菊粉酶可水解菊粉但不水解棉子糖,对蔗糖酶的活性较低,I/S为52,对菊粉的米氏常数Km为0.34 mol·L-1,最大反应速度vmax为0.53 mg·L-1·min-1。 The enzymatic characteristics of inulinase from Aspergillus niger inu-8 were studied in this paper.The main results were as follows： the suitable temperature for enzymatic activity was 30～60℃ and the optimum temperature was 45～55℃,the enzymatic activity declined sharply when the temperature exceeded 60℃;the activity of enzyme lost 80% under 80℃ hot water for 0.5h;the activity of enzyme remained high levels even in the condition of pH 4.0～6.0,and the best enzymatic activity was detected at pH 5.0;the Ca^2＋ had an activated effect on inulinase,Hg^2＋ and EDTA（ethylene diamine tetraacetic acid）was a strong inhibitor;the inulin was hydrolyzed and raffinose was not by the inulinase which had lower sugar activity,I/S was 52,the Michaelis constant Km for inulin was 0.34 mol·L^-1,the largest response rate vmax was 0.53mg·L^-1·min^-1.

关 键 词： 菊粉 菊粉酶 酶活性 酶学性质

领　　域： [生物学] [轻工技术与工程] [轻工技术与工程]