Please use this identifier to cite or link to this item:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/75553
Title: | Bacillus Iicheniformis 7 的細胞外耐熱性澱粉液化酵素 |
Authors: | 譚建安 |
Publication Year : | 1984 |
Degree: | 碩士 |
Abstract: | 中文摘要 由土壤分離出一株能產生對熱穩定之澱粉液化?的細菌,經鑑定並命名為Bacillus licheniformis 7。此一菌株生產澱粉液化?所需條件為50℃培養七天。此菌株在以Starch 2.5%,FeCl3-6H2O 0.05%, peptone 0.35%, yeast extract 0.6%,Na-citrate 0.2%,CaCl2.2H2O 0.008% 作培養基時,可獲得最佳酵素產量,產生之澱粉液化?經四個步驟純化,可純化26倍,回收率為21% ,純化酵素最適作用PH為9.0,最適作用溫度為90℃, PH6~9時很穩定。Hg+, Zn++,Mg++, Ni++, Mn++ 等金屬離子對酵素作用有抑制作用,而Na十,Fe+++, Cu++,Ba++ 則有促進作用,化學藥品K2MnO4之添加有抑制酵素活性之作用,2-Mercaptoethanol則可以促進酵素活性。 ABSTRACT A thermostable alpha-amylase producing bacteria has been isolated from soil and identified as Bacillus licheniformis. 7.Cultural conditions of this strain for alpha-amylase production were studied. The optimum temperature and incubation period for enzyme production were 50°C and 7 days respectively. Starch with a concentration of 2.5% was the best carbon source for enzyme production. Beside the above components, the addition of FeCl3.6H2O 0.05%, yeast extract 0.6%, peptone 0.35%, Na-citrate 0.2% and CaCl2.2HO 0.008% to the incubation medium could produce maximum enzyme activity. The enzyme was purified 26-fold with 21% recovery by a series of four steps. The purified enzyme showed maximal activity at 90℃ and pH9.0.91% of this activity remained at 97℃, even at 110℃, there was still 45% activity remained. The enzyme showed 100% stability at 40°C-70°C. Of the cations, Ba2+ Cu2+ Fe3+ Na+ showed stimulatory effect; whereas Hg2+, Mg2+, Mn2+, Ni2+, Zn2+ were inhibitory. K2MnO4 addition resulted in the complete loss of enzyme activity; whereas 2-Mercaptoethanol afforded protection of the enzyme activity. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/75553 |
Fulltext Rights: | 未授權 |
Appears in Collections: | 植物科學研究所 |
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.