title: Bicomponent lignocellulose thin films to study the role of surface lignin in cellulolytic reactions.
abstract: Ultrathin bicomponent films of cellulose and lignin derivatives were deposited on silica supports by spin coating, and after conversion into the respective polymer precursor, they were used as a model system to investigate interfacial phenomena relevant to lignocellulose biocatalysis. Film morphology, surface chemical composition, and wettability were determined by atomic force microscopy, X-ray photoelectron spectroscopy, and water contact angle, respectively. Phase separation of cellulose and lignin produced structures that resembled the cell wall of fibers and were used to monitor enzyme binding and cellulolytic reactions via quartz crystal microgravimetry. The rate and extent of hydrolysis was quantified by using kinetic models that indicated the role of the surface lignin domains in enzyme inhibition. Hydrophobic interactions between cellulases and the substrates and their critical role on irreversible adsorption were elucidated by using acetylated lignin films with different degrees of substitution. Overall, it is concluded that sensors based on the proposed ultrathin films of lignocellulose can facilitate a better understanding of the complex events that occur during bioconversion of cellulosic biomass.
authors.affiliation: Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695-8005, USA.
authors.forename: Ingrid C
authors.initials: IC
authors.lastname: Hoeger
authors.forename: Ilari
authors.initials: I
authors.lastname: Filpponen
authors.forename: Raquel
authors.initials: R
authors.lastname: Martin-Sampedro
authors.forename: Leena-Sisko
authors.initials: LS
authors.lastname: Johansson
authors.forename: Monika
authors.initials: M
authors.lastname: Osterberg
authors.forename: Janne
authors.initials: J
authors.lastname: Laine
authors.forename: Stephen
authors.initials: S
authors.lastname: Kelley
authors.forename: Orlando J
authors.initials: OJ
authors.lastname: Rojas
mesh_terms: D000327:Adsorption; D055162:Biocatalysis; D002473:Cell Wall / Q000737:chemistry / Q000378:metabolism; D002480:Cellulase / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D006868:Hydrolysis; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008031:Lignin / Q000737:chemistry / Q000494:pharmacology*; D011791:Quartz / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013329:Structure-Activity Relationship; D013499:Surface Properties
chemical_list: D020099:Coated Materials, Biocompatible; D004791:Enzyme Inhibitors; C036909:lignocellulose; D011791:Quartz; D012822:Silicon Dioxide; D008031:Lignin; D002480:Cellulase