Characterisation and application of glycanases secreted by Aspergillus terreus CCMI 498 and Trichoderma viride CCMI 84 for enzymatic deinking of mixed office wastepaper

Abstract

Two enzymatic extracts obtained from xylan-grown Aspergillus terreus CCMI 498 and cellulose-grown Trichoderma viride CCMI 84 were characterised for different glycanase activities. Both strains produce extracellular endoxylanase and endoglucanase enzymes. The enzymes optimal activity was found in the temperature range of 45-60 degrees C. Endoglucanase systems show identical activity profiles towards temperature, regardless of the strain and inducing substrate. Conversely, the endoxylanases produced by both strains showed maximal activity at different pH values (from 4.5 to 5.5), being the more acidic xylanase produced by T. viride grown on cellulose. The endoglucanase activities have an optimum pH at 4.5-5.0. The endoxylanase and endoglucanase activities exhibited high stability at 50 degrees C and pH 5.0. Mannanase, beta-xylosidase, and amylase activities were also found, being the first two activities only present for T. viride extract. These two enzymatic extracts were used for mixed office wastepaper (MOW) deinking. When the enzymatic extract from T. viride was used, a further increase of 24% in ink removal was obtained by comparison with the control. Both enzymes contributed to the improvement of the paper strength properties and the obtained results clearly indicate that the effective use of enzymes for deinking can also contribute to the pulp and paper properties improvement.

Engineering a Chimeric Lipase-cutinase (Lip-Cut) for Efficient Enzymatic Deinking of Waste Paper

“…All of the enzymes contributed to the improvement of the strength properties, with the exception of the tear index for the Lip deinked newspaper, which was marginally decreased. These results supported previous investigations by other authors concerning the occurrence of enhanced, decreased, or unchanged strength properties (Heise et al 1996;Marques et al 2003;Pala et al 2004;Pathak et al 2015). The chimeric Lip-Cut increased the strength properties of both pulp samples compared with the Lip, Cut, and Lip/Cut mixture.…”

“…In fact, the control (no enzyme action present) had an average ink removal efficiency of approximately 71% for both pulp samples (laser-printed paper and newspaper). This was probably the result of environmental factors, such as the pH, temperature, and washing, which enabled a partial release of ink particles from the fibers due to the breakdown of physical and chemical bonds (Marques et al 2003).…”

Biological deinking of inkjet-printed paper using Vibrio alginolyticus and its enzymes

“…The enzymatic treatment contributed to the improvement of the strength properties of the treated pulp compared to the untreated control. Similar improvement in physical and mechanical properties of enzyme-treated pulp has been reported [6,7]. The decreased drainage rates in enzyme-treated pulp results in faster machine speed resulting in significant savings in energy and cost [1].…”

The Enzymatic Deinking of Waste Papers by Engineered Bifunctional Chimeric Neutral Lipase – Endoglucanase

“…Because endoglucanase and lipase have shown high deinking efficiency (Gübitz et al 1998;Morkbak et al 1999;Marques et al 2003;Pelach et al 2003;Vyas and Lachke 2003), the authors assumed that the combined use of two enzymes could promote better deinking efficiency. With such assumption, a chimeric enzyme with endoglucanase and lipase activities was constructed in this study by an end-to-end fusion technique, in which the Lip catalytic domain at N-terminus was fused with the EG1 catalytic domain at C-terminus (Khandeparker and Numan 2008).…”