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Three trials were conducted to analyze a multi-enzyme compound produced by Aspergillus sulphureus in solid-state fermentation (SSF) as a potential feed additive. The results of the first trial showed that there were at least 5 non-starch polysaccharide enzymes: xylanase, β-glucanase, pectinase,mannase and carboxy methyl cellulase (CMCase)contained in the compound. Xylanase and β-glucanase showed good activities at pH 2.5-7.0, which were in the range of 649-1046 U/g and 444-648 U/g,respectively. Pectinase showed good activity in acidic solution (pH 2.5-3.0),which ranged from 195 to 917 U/g.Mannase showed high activity of 235-298 U/g at pH3.5-4.5 and the activity of CMCase was relatively constant at pH 2.5-7.0, which was in the range of 38.2-78.6 U/g. The second trial was aimed to test the stability of the enzymes in gastric liquor (pH 2.6) of finishing pigs and Na2 HPO4-gastric liquor ( pH 5.5 ).After 6 h incubation at 40℃ in gastric liquor, the retained activity of xylanase, β-glucanase, pectinase,mannase and CMCase was 26.3% ,65.0% ,71.0%,74.8% and 85.6%, respectively. While after 6 h incubation at 40℃ in Na2HPO4-gastric liquor, the retained activity of xylanase, β-glucanase, pectinase,mannase and CMCase was 87.9% ,91.1% ,92.3%,95.0%, and 97.5%, respectvely. The third trial was carried out in a jejunum liquor ( pH 5.8,200 mL),which contained 0.2 g of the multi-enzyme compound and 10 g of soybean hull or wheat bran, respectively.After 8 h incubation at 40℃,18.7% of soybean hull and 20.1% of wheat bran could be degraded to soluble saccharide, respectively. Compared with the traditional methods for feed enzyme testing which involve feeding animals for 1-3 months, enzyme assay in this way was relatively convenient.