期刊论文

Study on the mutation breeding of raw-starch-hydrolysing amylase-producing strain and the enzyme properties

中文

食品与机械

1003-5788

2009

25

2

11-14,33

10.13652/j.issn.1003-5788.2009.02.007

国家科技支撑项目（编号:2007BAD41B03）；

本校为第一机构

以产生淀粉酶菌株Aspergillus niger AF-0为出发菌株，先后经紫外（UV）、亚硝基胍（NTG）诱变，选育得到了一株产酶活性较高的突变株，其所产马铃薯生淀粉酶的酶活力达43．8U／mL，比原初酶活力19．3U／mL提高了1．3倍。在此基础上，对该酶的部分酶学性质进行了研究。结果表明，该酶的最适反应温度为55℃，在60℃以下稳定；最适反应pH为4．0，在pH3．5—5．0范围内稳定；Mn^2＋，Fe^2＋，Zn^2＋，Mg^2＋，Ca^2＋，Ba^2＋对该酶有一定的激活作用，而Cu^2＋，K^＋，Na^＋则抑制酶的活性；该酶以形成孔洞的方式由外向内作用于马铃薯淀粉颗粒。

The raw-starch-hydrolysing amylase-producing strain Aspergillus niger AF-0 was used as original strain which was induced by UV and NTG for increasing the ability of enzyme production. One mutant with high yield of raw-starch-hydrolysing amylase was selected. The enzyme activity of this mutant increased from 19.3 U/mL to 43.8 U/mL, increased by 1.3 times. The enzyme produced by the mutant exhibited the maximun activity at pH 4.0 and 55 ℃. Furthermore, the enzyme performed stable over thepH range of 3.5 -5.0 and at 60 ℃. Mn^2＋ Fe^2＋, Zn^2＋, ...