Amongs three strains: H. annosus, T. versicolor and C. unicolor, tested for laccase production, C.unicolor was chosen as the best producer of the enzyme. The effective method of cultivation was developed that resulted in high laccase activity and low protease amount. The following scheme was suggested: slant – inoculum with silica gel as additive in broth – two successive cultivations with silica gel in broth. It was found that the culture should be stopped between 10 and 12 day. Filtrated enzyme fluid was used for immobilization on various carriers: wood shavings (pine, birch, oak) and commercial supports (Eupergit C, Dowex Marathon, Amberlite IRA 900, DEAE-Granocel-2000, BA/EGDMA). Physical adsorption and covalent attachment were applied as testing methods of immobilization. The best results were obtained when DEAE-Granocel-2000, activated with divinyl sulfone was used as the carrier (measured activity 22.1 U^.ml^-1). The optimization of immobilization conditions showed that the highest enzymatic activity of laccase was observed in pH 7.0 of coupling mixture without NaCl.

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