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A raw starch saccharifying enzyme from Aspergillus sp. SN-871 was purified by ammonium sulfate precipitation, DEAE-cellulose column chromatography, CM-Sephadex C-50 column chromatography and Sephadex G-75 gel filtration. The specific activity of purified enzyme was 18 fold and the yeild was 13.40%. The molecular weight of the purified enzyme was estimated as approximately 40,000 dalton by the method of Andrews gel filtration. The optimum pH and temperature for this enzyme were found to be 4 and 40℃, respectively and the stable range of pH was 2 to 5. The enzyme was themostable at below 60℃ and inactivated at 70℃. It showed a tendency to increase the enzyme activity under the presence of 0.01 M BaCl₂, but under 0.01 MPb (NO₃)₂, AgSO₄, and K₃Fe(CN)_6 and citric acid etc. inhibited it completely. The substrate specifity of enzyme showed a tendency to increase the enzyme activity under addition of dextrin and glycogen, but under saccharose inhibited it. COD removal rate of Aspergillus sp. SN-871 was approximately 67 to 68%.
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