Synergistic removal of dyes by Myrothecium verrucaria immobilization on a chitosan–Fe membrane

A green efficient strategy for the combination of biodegradation and adsorption methods is urgently desired nowadays to degrade dyes in an economical and effective way. In this study, a kind of novel, environmentally friendly and efficient hybrid for the fungus and chitosan–Fe membrane has been fabricated by the alginate approach. Myrothecium verrucaria I-5 and C-1, deuteromycete fungi capable of producing laccase to degrade dyes, have been used. It is found that the chitosan–Fe membrane can excellently immobilize the fungi mycelia and enzyme, and after the immobilization, the fungi and enzyme still maintain a high activity after the dye decolorization. Also, the immobilized fungi membranes have been proved to have a high efficiency for dye decolorization. Simultaneously, the decolorization ability of the crude enzymes, which are extracted from I-5 and C-1 medium, and the decolorization ability of chitosan–Fe membrane are also investigated, respectively. The results demonstrate that the dyes can be removed by the fungi and the membrane synergistically. In addition, different kinds of dyes are successfully removed with chitosan–Fe immobilized fungi membranes. These results demonstrate that dyes are first adsorbed on the chitosan–Fe membrane, decreasing the toxicity to the fungus, and then bio-degraded by the laccase produced from the fungi on the membrane.