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Advisor(s)
Abstract(s)
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 8C.
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 8C and
pH 5.0. Mannanase, b-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.
Description
Keywords
Hemicellulase Endoglucanase Amylase Enzymatic deinking Aspergillus terreus Trichoderma viride
Pedagogical Context
Citation
MARQUES, S. e outros - Characterization and application of glycanases secreted by Aspergillus terreus CCMI 498 and Trichoderma viride CCMI 84 for enzymatic deinking of mixed office wastepaper. Journal of Biotechnology. Vol. 100, n.º 3 (2003), p. 209-219.