Formation and purification of laccase by the white-rot fungus Trametes pubescens

【Objcetive】 The study was about laccase formation and purification by white-rot fungus Trametes pubescens MB 89.【Method】 The white-rot fungus Trametes pubescens MB 89 had been identified as an excellent producer of the industrially important enzyme laccase.Extracellular laccase formation could be considerably stimulated by the addition of Cu(Ⅱ) in the millimolar range to a simple,glucose-based culture medium.In this study,the final concentration of copper was 1 mmol/L in the medium,which was added CuSO4·5H2O after 10 d cultivation.When using a basal GP(glycerol-peptone) medium for cultures contained 40 g/L glycerol,15 g/L peptone from meat and 1 g/L MgSO4·7H2O,significant laccase formation by T.pubescens only started when glucose was completely consumed from the culture medium.DEAE-Sepharose was used for laccase purification.【Result】 Laccase activity increased slowly during the 10 d cultivation.Maximal laccase activiy obtained in shake-flask cultures was approx 57.10 U/mL on the 19th d.Purity of the laccase was above 53% by using DEAE-Sepharose.【Conclusion】 T.pubescens MB89 could be the productive strain of laccase in industry.Cu2+ was available for laccase formation.