Biobleaching of Pulp and Paper Mill Effluents by Phanerochaete chrysosporium

Abstract The potential of white rot fungi, namely, Polyporus versicolor FRI 165, Polyporus hirsutus FRI 534, Polyporus hirsutus FRI 2862, Phanerochaete chrysosporium BKMF 1767 and Sporotrichum pulverulentum for the reduction of colour of pretreated pulp and paper mill effluents under sterilised and unsterilised conditions has been evaluated. Of these, P. chrysosporium BKMF 1767 cultured under sterilised conditions supported maximum colour reduction after 7 days of growth. The optimisation of the process parameters showed that the addition of nutrient sails in selective combination marginally improved the colour reduction. The 7‐day‐old growth of culture at 20% (v/v) inoculum concentration resulted in maximum decolourisation (69.6%) of the effluent with pH adjusted to 4.5 at 40°C along with more than 50% reduction in biological oxygen demand (BOD) and chemical oxygen demand (COD). The irradiation of the effluent with UV light had apparently no effect on the colour, BOD and COD reduction by P. chrysosporium.