A Study of Characteristics of Pectinesterase, Polygalacturonase and Peroxidase in Kimchi Materials
The object of this study was to investigate the characteristics of pectinesterase(PE), polygalacturonase(PG) and Peroxidase(POD) in Kimchi materials. The results were as follows : 1. The specific activities of PEs in Korean cabbage, Korean raddish, garlic and ginger were 200 unit/mg protein, 23.1 unit/mg protein, 0.8 unit/mg protein and 32 unit/mg protein, respectively. The optimum pHs of PEs in all materials were between 7 to 8. The concentrations of NaCl, CaCl2 which showed the highest activities of PEs were 0.2~0.3M NaCl, 50 mM CaCl2 in Korean cabbage and raddish, 0.05 M NaCl, 20 mM CaCl2 in garlic and 0.2 M NaCl, 20 mM CaCl2 in ginger. 2. The specific activities and the optimum pHs of PGs were 1.5 unit/mg protein and pH 4.5 in Korean cabbage, 1.6 unit/mg protein and pH 4.5~5.5M in Korean raddish, 0.06 unit/mg protein and pH 3.0~3.5M in garlic, and 0.06 unit/mg protein and CaCl2 in ginger. The concentrations of NaCl, CaCl2 which showed the highest activities of PGs were 0.1~0.2M NaCl and 0.15~0.2mM mM CaCl2 in all materials. 3. The specific activities and the optimum pHs of PODs in Korean cabbage, Korean raddish, garlic and ginger were 71.3 unit/mg protein ; pH 6.0. 769 unit/mg protein ; pH 5.5, 1.09 unit/mg protein ; pH 4.5 and 12.7 unit/mg protein ; pH 5.0~5.5M, respectively. POD activities were not decreased in Korean cabbage, but decreased in Korean raddish by the increase of NaCl, CaCl2 concentrations. In garlic and ginger, POD activities were a little slightly affected by the increase of NaCl, CaCl2 concentrations.