Biodeinking of Photocopier Waste Paper Effluent by Fungal Cellulase under Solid State Fermentation

Aims: In this study, the purified cellulase was examined for its ability to deink the photocopier waste paper effluent and the application of enzymatic deinking improved ink removal.

Study Design: OFAT (One Factor At a Time).

Place and Duration of Study: Medical Labs Department of Unayza Community College, Qassim University, KSA between October 2012 and April 2013.

Methodology: Four fungal isolates were isolated from rice husks and screened for their production of cellulase and the most potent ones were selected. The resultant extracts were identified and used for deinking of photocopier waste paper. One isolate that showed efficient deinking and maximum cellulase production was identified morphologically and microscopically.

Results: The enzyme was successively optimized for its maximum productivity and purified by precipitation with 80% ammonium sulfate followed by chromatography on G-100 Sephadex. The purification procedure provided 2.36 folds purification with 64.78% yield recovery of cellulase. The maximum production was achieved in flasks with shaking speed of 200 rpm at pH 5.0, 30°C and incubation time of 5 days. SDS-PAGE indicated that the molecular weight of the purified cellulase was 71.6 KDa. Results also revealed that, the ink color was removed gradually by increasing the reaction time between cellulase and the effluent and the maximum color removal was achieved after 9 hours.

Conclusion: This study suggested that toxic pollutants like waste paper effluents (concentrated in industrial wastes and contaminated sites) can potentially be eliminated by low cost bioremediation systems using microbial cultures. The knowledge about the optimum environmental factors or conditions could help to employ biological approaches efficiently to clean up the water discharged from waste paper recycling industry. Mucor hiemalis cellulase effectively deinked wastepaper effluents.