Evaluation of Lignin-Based Black Liquor Decolorization by Trametes versicolor U 80

Bioethanol second generation (G-2) production process generated black liquor that need to treat before the disposal to prevent environmental pollution. Usually, coagulation technology using polyaluminium chloride was employed to precipitate dissolved lignin and intended to decolorize black liquor. However, this single work is not effective to treat black liquor, so that it requires another work to treat remain brownish liquor. Isolated fungal strain from Japan Trametes versicolor U 80 and Phanerochaete chrysosporium are white rot fungi that are known in ligninolytic enzymes secretion to biodegrade soluble lignin. Decolorization of black and brownish liquor is an indicator of fungi works since lignin is known as the colour agent in liquor colouration. This work evaluated black and brownish liquor decolorization using both fungi that correspond to fungal growth. Liquor toxicity was observed based on mycelial dry weight after 30 days incubation as the presumption of the connection of fungal growth and decolorization. The biosorption from the dead cell was also evaluated for fungal adsorption capability in black and brownish decolorization. As the result, T. versicolor U 80 was able to decolorize brownish liquor 51.5% after 21 days incubation and 68.6% black liquor at 15 days incubation. MnP and Laccase enzymes activity in 15 and 21 days are correlated to those decolorized results. The dead cell was also able to decolorize 67.3% brownish liquor and 25.1% black liquor after 15 days incubation as biosorption mechanism. This research described fungal potential in decolorization as the simple black liquor treatment technology and gave valuable information related to environmental friendly decolorization process.