抄録
Melanoidin decolorizing enzymes (MDE) were extracted from mycelia of Coriolus versicolor Ps4a and purified by DEAE-Sephadex, DEAE-Sephacel and Sephadex G-200 column chromatographies. MDE of this strain consisted of a main fraction, P-fraction, and a minor fraction, E-fraction, and the P-fraction was composed of at least five enzymes. P-III and P-IV in the P-fraction were picked as typical enzymes of this strain, and their enzymatic properties were investigated. P-III had a molecular weight of 48, 400-50, 000, an optimum pH of 5.5 and an optimum temperature of 30-35°C. P-III required glucose and O2 for the appearance of the activity, and was inhibited by p-CMB, N-BSI, Ag+ and o-phenanthroline.
On the other hand, P-IV had a molecular weight of 43, 800-45, 000, an optimum pH of 4.0-4.5 and an optimum temperature of 30-35°C. P-IV could decolorize melanoidin in the absence of glucose and O2, and was inhibited weakly by Ag+, p-CME and N-BSI. P-IV is the enzyme that attacks the melanoidin directly in comparison with P-III which attacks melanoidin indirectly as in the sub-reaction of sugar oxidase.
Incidentally, a multiplicative effect between P-III and P-IV for decolorization was observed.
