生淀粉糖化菌NL-3的发酵条件  

Fermentation conditions of rawstarch glucoamylase producing strain

作　　者：李俊刚[1,2] 方善康[1,2] 

机构地区：[1]绵阳师范高等专科学校生物系 [2]山东大学微生物系

出　　处：《西南师范大学学报（自然科学版）》1998年第1期92-96,共5页Journal of Southwest China Normal University(Natural Science Edition)

基　　金：四川省教委青年科研基金

摘　　要：以黑曲霉（Ａｓｐｅｒｇｉｌｕｓｎｉｇｅｒ）５２３原生质体为对象，经激光、紫外线和亚硝基胍复合诱变，选育出高产生淀粉糖化酶突变株黑曲霉ＮＬ３，其生淀粉酶活力为１５６Ｕ／ｍｌ．产酶最适培养条件为：起始ｐＨ４５，３０℃，９６ｈ产酶量达最高．Ｋ＋，Ｍｇ２＋对ＮＬ３产生淀粉糖化酶有促进作用；Ｚｎ２＋对产酶有抑制作用．酶的最适作用条件为：以玉米淀粉为底物的最适温度５０℃，最适ｐＨ４５；以甘薯淀粉、马铃薯淀粉为底物时最适温度６０℃，最适ｐＨ４０～４５．酶在６０℃保温１５ｍｉｎ，玉米淀粉为底物时酶剩余活力为８０％；甘薯淀粉、马铃薯淀粉为底物时酶剩余活力为９８％． mutant strain NL3 with high yield of rawstarch digesting glucoamylase was obtained from protoplast of asperillus niger 523 treated with chemical mutation agent NmethyN′nitrosoguanidine(MNNG) and laser & UN radiation.The enzyme activity was 156U/ml.The optimal culture conditions were found:inital pH45 at 30℃ for 96h.K+,Mg2+ ions enhanced the enzyme activity,Whereas Zn2+ inhibited it.The optimal conditions for enzyme catalysis were pH45 at 50℃ for corn starch and pH40～45 for sweat potato starch and potato starch respectively.After incubation at 60℃ for 15min,enzyme kept 80% activity for corn starch,and 98% activity for sweat potato starch and potato starch.

关 键 词：黑曲霉 生淀粉糖化酶 原生质体 诱变 发酵 

分 类 号：TQ925.1[轻工技术与工程—发酵工程] TS201.3