title: Mechanism of the positive effect of poly(ethylene glycol) addition in enzymatic hydrolysis of steam pretreated lignocelluloses.
abstract: The efficiency of enzymatic hydrolysis of lignocellulses can be increased by addition of surfactants and polymers, such as poly(ethylene glycol) (PEG). The effect of PEG addition on the cellulase adsorption was tested on various steam pretreated lignocellulose substrates (spruce, willow, hemp, corn stover, wheat straw, sweet sorghum bagasse). A positive effect of PEG addition was observed, as protein adsorption has decreased and free enzyme activities (FP, β-glucosidase) have increased due to the additive. However, the degree of enhancement differed among the substrates, being highest on steam pretreated spruce. Results of lignin analysis (pyrolysis-GC/MS, (31)P NMR) suggest that the effect of PEG addition is in connection with the amount of unsubstituted phenolic hydroxyl groups of lignin in the substrate. Adsorption experiments using two commercial enzyme preparations, Celluclast 1.5L (Trichoderma reesei cellulase) and Novozym 188 (Aspergillus niger β-glucosidase) suggested that enzyme origins affected on the adsorptivity of β-glucosidases.
authors.affiliation: Budapest University of Technology and Economics, Department of Applied Biotechnology and Food Science, Budapest, Hungary. balint_sipos@mkt.bme.hu
authors.forename: Bálint
authors.initials: B
authors.lastname: Sipos
authors.forename: Mátyás
authors.initials: M
authors.lastname: Szilágyi
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Sebestyén
authors.forename: Raffaella
authors.initials: R
authors.lastname: Perazzini
authors.forename: Dóra
authors.initials: D
authors.lastname: Dienes
authors.forename: Emma
authors.initials: E
authors.lastname: Jakab
authors.forename: Claudia
authors.initials: C
authors.lastname: Crestini
authors.forename: Kati
authors.initials: K
authors.lastname: Réczey
mesh_terms: D000327:Adsorption; D002264:Carboxylic Acids / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D004798:Enzymes / Q000737:chemistry*; D005374:Filtration; D008401:Gas Chromatography-Mass Spectrometry; D006358:Hot Temperature; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010940:Plant Proteins / Q000032:analysis; D010944:Plants / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D013227:Steam; D001617:beta-Glucosidase / Q000737:chemistry
chemical_list: D002264:Carboxylic Acids; D004798:Enzymes; D010940:Plant Proteins; D013227:Steam; C036909:lignocellulose; D011092:Polyethylene Glycols; D008031:Lignin; D001617:beta-Glucosidase