Chemical Pulping process generates kraft black liquor which consists of highly alkaline solution. This study investigates the capability of three native fungi to decolorize kraft black liquor on solid and liquid medium under different concentrations. Qualitative assessment of fungal decolorization was observed by plate assay method. Out of the three fungi studied, Nigrospora sp. showed maximum growth (1.2 cm day-1 ) and decolorization halo (0.9 cm day-1 ) in malt extract agar medium containing 10 % black liquor. On the other hand, relatively slow fungal growth was observed in 20 % black liquor agar medium. In liquid medium, decolorization of black liquor was mostly influenced by the concentration of black liquor and fungal strain. The highest decolorization (61% ) and COD removal (58.7 %) was observed by Nigrospora sp. Furthermore, mixed fungal culture enhanced the efficiency of COD and color removal upto 71.5 % and 73 %, respectively. A positive correlation was observed between color and COD removal (r = 0.99). These results indicate that the fungal strain Nigrospora has huge potential for treatment of kraft black liquor.
