Abstract: The β-D-galactosidase from K. fragilis LFS-8611 was purified by chromatography methods, and the purity ofenzyme was identified by sodium dodecyl sulphate polyacrylamide gel electrophoresis(SDS-PAGE). The enzyme was purified about 45.8 fold with a yield of 16% total activity by successive ammonium sulfate-fractionation, CM-Sepharose CL-6B, DEAE-Sepharose CL-6B, and Sephacryl S-200 column chromatography. When the purified enzyme samples were subjected to SDS-PAGE, one single band was observed, which suggested that the enzyme samples were almost pure. The molecular weightestimated for K. fragilis LFS-8611 β-D-galactosidase by PAGE was 60000.

Key words: D-galactosidase, purification