Abstract: In order to study the enzyme activity and bacteriostasis of Penicillium thomii PT95 and Q1 strains,folin phenol method,carboxymethyl cellulose sodium (CMC-Na) saccharifying power method,dinitrosalicylic acid (DNS) colorimetric method and p-nitrophenol method were used to determine the activities of protease,cellulase,amylase and lipase.The inhibition of fermentation filtrate on Staphyloccocus aureus,Bacillus subtilis and Escherichia coli were determined by oxford cup method.And the minimum inhibitory concentration of fermentation filtrate of Penicillium thomii PT95 and Q1 strains were determined.The results showed that the protease activity of PT95 strain was 230.473 U,cellulase activity was 3.463 U,amylase activity was 1.679 MMU and lipase activity was 10.793 U,while that of Q1 strain was 167.247 U,cellulase activity was 2.147 U,amylase activity was 1.402 MMU and lipase activity was 6.350 U.The bacteriostasis rates of PT95 strain to Bacillus subtilis and Escherichia coli were 53.73%and 19.47% respectively.Q1 strain had bacteriostasis effects on all three tested bacteria.The bacteriostatic rate to Bacillus subtilis,Staphylococcus aureus and Escherichia coli was 56.37%,26.87% and 19.47%respectively.There were bacteriostasis in the fermentation broth of both strains.The bacteriostasis rate of the two strains to Bacillus subtilis was the highest.The minimum inhibitory concentration of the fermentation broth of the two strains to Bacillus subtilis was 0.64 and 0.32 mg/mL,respectively.

Key words: Penicillium thomii, digestive enzyme, folin phenol method, carboxymethyl cellulose sodium (CMC-Na) saccharifying power method, dinitrosalicylic acid (DNS) colorimetric method, p-nitrophenol method