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A moderately thermophilic, alkalophlic and powerful crystalline cellulose-digesting bacterium, Bacillus K-12, was isolated from filter paper wastes and found to be similar to Bacillus circulans or Bacillus pumilis, except for its ability to grow at a moderately high pH and temperature. The isolate grew at a pH ranging from 6 to 10 and at a temperature ranging from 35 to 65℃ and produced a large amount of cellulase components containing avicelase, xylanase, CMCase, and FPase when grown in avicel medium for 5 to 7 days at 50℃. The crude enzyme preparation from the culture broth hydrolyzed xylan, raw starch, pullulan and β-1,3 glucan such as laminarin. Furthermore, the enzyme hydrolyzed crystalline cellulose to celloblose and glucose and had a broad pH activity curve (pH 6∼9). The enzyme was stable up to 70℃.
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