title: Dissecting the effect of chemical additives on the enzymatic hydrolysis of pretreated wheat straw.
abstract: Chemical additives were examined for ability to increase the enzymatic hydrolysis of thermo-acidically pretreated wheat straw by Trichoderma reesei cellulase at 50 °C. Semi-empirical descriptors derived from the hydrolysis time courses were applied to compare influence of these additives on lignocellulose bioconversion on a kinetic level, presenting a novel view on their mechanism of action. Focus was on rate retardation during hydrolysis, substrate conversion and enzyme adsorption. PEG 8000 enabled a reduction of enzyme loading by 50% while retaining the same conversion of 67% after 24h. For the first time, a beneficial effect of urea is reported, increasing the final substrate conversion after 48 h by 16%. The cationic surfactant cetyl-trimethylammonium bromide (CTAB) enhanced the hydrolysis rate at extended reaction time (rlim) by 34% and reduced reaction time by 28%. A combination of PEG 8000 and urea increased sugar release more than additives used individually.
authors.affiliation: Austrian Centre of Industrial Biotechnology (ACIB), Petersgasse 14, 8010 Graz, Austria.
authors.forename: Mareike
authors.initials: M
authors.lastname: Monschein
authors.affiliation: CLARIANT Produkte (Deutschland) GmbH, Group Biotechnology, Staffelseestraße 6, 81477 Munich, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Reisinger
authors.affiliation: Austrian Centre of Industrial Biotechnology (ACIB), Petersgasse 14, 8010 Graz, Austria; Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 12/I, 8010 Graz, Austria. Electronic address: bernd.nidetzky@tugraz.at.
authors.forename: Bernd
authors.initials: B
authors.lastname: Nidetzky
mesh_terms: D000327:Adsorption; D001709:Biotechnology / Q000379:methods*; D050260:Carbohydrate Metabolism / Q000187:drug effects; D002480:Cellulase / Q000378:metabolism*; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000494:pharmacology*; D006868:Hydrolysis / Q000187:drug effects; D007700:Kinetics; D011092:Polyethylene Glycols / Q000494:pharmacology*; D013997:Time Factors; D014242:Trichoderma / Q000201:enzymology; D014908:Triticum / Q000737:chemistry* / Q000187:drug effects; D014508:Urea / Q000494:pharmacology*; D014866:Waste Products
chemical_list: D002593:Cetrimonium Compounds; D014866:Waste Products; D011092:Polyethylene Glycols; D014508:Urea; D002480:Cellulase; D000077286:Cetrimonium
keywords: Cellulase; Chemical additives; Enzymatic hydrolysis; Protein adsorption; Urea