Niziołek S
Department of Biochemistry, Warsaw Agricultural University, Poland.
Acta Microbiol Pol. 1997;46(4):357-62.
The production of extracellular beta-amylase by some Bacillus cereus, Bacillus megaterium and Bacillus polymyxa [corrected] strains was investigated, and the maximal yields of the enzyme were 3.6; 9.3 and 20.4 U/mL of the culture fluid, respectively (U, 1 mumol of maltose equivalent per min at 30 degrees C). Several cultivation media were used for beta-amylase production. Bacillus cereus and some strains of Bacillus megaterium gave good yields of beta-amylase only in medium with the addition of nutrient broth. However, beta-amylase produced during growth in protein rich medium (nutrient broth) was highly unstable, probably due to inactivation by proteolytic enzymes co-existing in the culture fluid. Bacillus polymyxa [corrected] strains can produce good yields of beta-amylase on a semi-synthetic medium consisting of inorganic salts, potato starch and inexpensive soybean extract instead of costly peptone and meat extract. The most potential beta-amylase producer was the strain Bacillus polymyxa [corrected] NCIB 8524. The tested Bacillus megaterium and Bacillus polymyxa [corrected] strains were apparently differentiated by temperature cultivation (30 and 37 degrees C) suitable for beta-amylase amylase yield.
研究了某些蜡样芽孢杆菌、巨大芽孢杆菌和多粘芽孢杆菌[已校正]菌株胞外β-淀粉酶的产生情况，该酶的最大产量分别为3.6、9.3和20.4 U/mL培养液（U，30℃下每分钟产生1 μmol麦芽糖当量）。使用了几种培养基来生产β-淀粉酶。蜡样芽孢杆菌和一些巨大芽孢杆菌菌株仅在添加了营养肉汤的培养基中能高产β-淀粉酶。然而，在富含蛋白质的培养基（营养肉汤）中生长期间产生的β-淀粉酶非常不稳定，这可能是由于培养液中同时存在的蛋白水解酶使其失活。多粘芽孢杆菌[已校正]菌株可以在由无机盐、马铃薯淀粉和廉价大豆提取物组成的半合成培养基上高产β-淀粉酶，而无需使用昂贵的蛋白胨和肉提取物。最具潜力的β-淀粉酶产生菌株是多粘芽孢杆菌[已校正]NCIB 8524。所测试的巨大芽孢杆菌和多粘芽孢杆菌[已校正]菌株在适合β-淀粉酶产量的温度培养（30℃和37℃）下表现出明显差异。
