Characterisation of biologically pretreated raw materials for biopulping process.

Biopulping, the treatment of wood chips by white rot fungi and subsequent chip refining is envisioned as a method for saving energy and making a stronger paper product. The present study aims to find suitability of two fungal isolates Phellinus pectinatus and Daedaleopsis confragosa for the process of biopulping and the characteristion of the biologically pretreated raw materials for biopulping. Two combinations of raw samples, Bamboo: wood shavings and Bamboo: wood shavings: Sorghum halepense culm were prepared and subjected to four different pretreatment. Daedaleopsis confragosa was found to be effective in biopulping with a supplement of Potato dextrose broth medium to the raw material.

Novel application of fungal Phanerochaete sp. and xylanase for reduction in pollution load of paper mill effluent.

Four different strategies of pulping and bleaching were carried out to develop alternative mechanistic ecoenvironmental friendly approaches and generated effluent was characterised. Strategy-I included Phanerochaete sp. fungal pretreatment followed by conventional bleaching, whereas in strategy-II, fungal pretreatment was followed by enzyme xylanase aided bleaching. Strategy-III also included xylanase supplement but without prior fungal pretreatment. Chemically driven pulping and bleaching was the IV strategy. Conventional CDEOPD1D2 sequence of bleaching was used for strategy–I and IV whereas XCDEOPD1D2 sequence was applied to strategy–II and III. Strategy–II was responsible for 27.5% reduction in Kappa no. whereas the maximum (27.5%) reduction in refining energy was observed with strategy–II. Biobleaching strategies– II and III were helpful in saving 37.3 and 20.3% of elemental chlorine (Cl2) and 30.8 and 23.1% of chlorine dioxide (ClO2), respectively. In comparison to control (strategy-IV), strategy II resulted in maximum pollution load reduction of chemical oxygen demand (COD), biological oxygen demand (BOD), color and adsorbable organic halides (AOX) upto 57, 60, 30 and 43.6%, respectively.

Evaluation of White-rot Fungi for Biopulping of Wood

Ergosterol involves in fungal cell growth as a major component in fungal cell membranes. It can be an indicator that shows the fungal activity, and its content depends on the fungal strains, culture, growth conditions and so on. In this study, fungal activities and growth patterns of three white-rot fungi strains isolated in Korea were evaluated by determination of ergosterol contents during the incubation. Wood decay test and chemical analyses of wood were also performed to verify the relationship between fungal activity and wood degrading capacity of white-rot fungi for 60 days. In the results of experiments, it is considered that the test strains selectively degrade large amount of lignin in wood at the early stage of decay. Especially, Phanerochaete chrysosporium showed the best capability on selective degradation of lignin among the test fungi. It is suggested that the determination of ergosterol content in the fungal culture during the incubation is the simple and effective screening method of white-rot fungi for the application to biopulping of wood.