Abstract
The impact of oxidative modification and partial removal of lignin by
laccase–mediator treatments on the enzymatic hydrolysis of
steam‐pretreated softwood (SPS) was evaluated. Two mediators, N‐hydroxy‐N‐phenylacetamide (NHA) and its acetylated precursor, were oxidized by the laccase from Trametes hirsuta,
and their effects on the activity of cellulolytic enzymes and on the
hydrolysis yield of SPS were examined. Both simultaneous and sequential
combinations of laccase–mediator treatments with commercial cellulases
increased the sugar yield in the enzymatic hydrolysis of SPS. The
maximal increase was 21% when a sequential treatment was applied.
Laccase treatment alone was also shown to improve hydrolysis. NHA
oxidized by laccase inhibited significantly the cellulases of Trichoderma reesei,
but the presence of the solid substrate protected the activities
against oxidative inactivation. Surface analysis of the lignocellulosic
substrate before and after the laccase and cellulase treatments revealed
an enrichment of lignin and an increase of carboxylic groups on the
surface of the hydrolysis residue.
Original language | English |
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Pages (from-to) | 550-557 |
Journal | Biotechnology and Bioengineering |
Volume | 86 |
Issue number | 5 |
DOIs | |
Publication status | Published - 2004 |
MoE publication type | A1 Journal article-refereed |
Keywords
- cellulose hydrolysis
- role of lignin
- surface modification