Optimization of culture medium composition for MnPeroxidase and tyrosinase production during Reactive Black 5 decolourization by yeast Trichosporon akiyoshidainum.

MARTORELL, MARIA M.; PAJOT, HIPOLITO F.; ROVATI, JOSE I.; CASTRO, GUILLERMO R.; FIGUEROA, LUCIA I. C.

Conferencia; New Horizons in Biotechnology; 2011

Biotech research society of India

Decolourization and degradation of diazo Reactive Black 5 dye was carried out by yeast Trichosporon akiyoshidainum. A nine-factor Plackett-Burman design was employed for study and optimization of decolourization process and production of MnPeroxidase and tyrosinase activities. In the present study, 26 individual experiments were conducted and three responses were evaluated. Raising yeast extract concentration significantly enhances decolourization and MnPeroxidase production. Carbon and nitrogen sources, glucose and (NH4)2SO4, showed no significant effect on any response over the tested concentration range. Other culture medium components such as CaCl2 or MgSO4 could be excluded from the medium formula as they had no effect on the evaluated responses. Metal ions (Fe, Cu and Mn), showed different effects on decolourization or enzymatic activities. Addition of cupper significantly enhanced MnP activity and decreased dye decolourization. On the contrary iron had a positive effect on decolourization and no effect on enzymes production. Oddly, increasing manganese concentration had a positive effect on tyrosinase production but without affecting decolourization or MnPeroxidase activity. These results strongly suggest that dye decolourization should be regarded as a complex multi-enzymatic process where optimal media composition should arise as a compromise between those optimal for each implied enzyme production.