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Purification and Characterization of β-amylase from Bacillus polymyxa No. 26-1 |
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| Authors: | CHEON-BAE SOHN SANG-MI LEE MYUNG-HEE KIM JEONG HEON KO KYOUNG-SOOK KIM JI-EUN CHANG YONG-KEUN AHN CHEORL-HO KIM |
| Affiliation: | Authors Cheorl-Ho Kim, K-S. Kim, Chang, and Ko are with the Laboratory of Molecular &Cellular Biology, Korea Research Institute of Bioscience &Biotechnology, K.I.S.T, Taejon 305–600, South Korea.;Author Ahn's present address: Dept. of Food Nutrition, Chungchung Junior College, Chungbuk, South Korea.;Present address of authors Sohn, Lee, and M-H. Kim: Dept. of Food Nutrition, Chungnam National Univ., Taejon, South Korea. Ad-dress inquiries to Dr. Cheorl-Ho Kim. |
| Abstract: | An extracellular β-amylase, which was easily adsorbable onto raw corn starch, was purified 22.5-fold from a new isolate of Bacillus polymyxa No 26–1 with a Mr of 53 kDa and pI of 9.1. The optimum temperature was 45°C and pH 5.5 for raw corn starch. Thermal stability at 40°C and pH stability at 5.0–8.5 were shown. The degradation ofraw starch by β-amylase was greatly stimulated by pullulanase addition. Scanning electron micrographs revealed that starch granule degradation by the enzyme alone occured at the equatorial grooves of lecticular granules. Corn starch granules hydrolyzed by β-amylase had large holes on granule surfaces. |
| Keywords: | β-amylase raw starch saccharifying enzyme Bacillus polymyxa No 26–1 |