title: Immobilization of indigenous holocellulase on iron oxide (Fe2O3) nanoparticles enhanced hydrolysis of alkali pretreated paddy straw.
abstract: The holocellulase from Aspergillus niger SH3 was characterized and found to contain 125 proteins including cellulases (26), hemicellulases (21), chitinases (10), esterases (6), amylases (4) and hypothetical protein (32). The crude enzyme was immobilized on five different nanoparticles (NPs) via physical adsorption and covalent coupling methods. The enzyme-nanoparticle complexes (ENC) were screened for protein binding, enzymatic activities and immobilization efficiency. Magnetic enzyme-nanoparticle complexes (MENC) showed higher immobilization efficiency (60-80%) for most of the enzymes. MENC also showed better catalytic efficiencies in term of higher Vmaxand lower Kmthan free enzyme. Saccharification yields from alkali treated paddy straw were higher (375.39mg/gds) for covalently immobilized MENC than free enzyme (339.99mg/gds). The immobilized enzyme was used for two cycles of saccharification with 55% enzyme recovery. Hence, this study for the first time demonstrated the immobilization of indigenous enzyme and its utilization for saccharification of paddy straw.
authors.affiliation: Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110 012, India.
authors.forename: Ajay
authors.initials: A
authors.lastname: Kumar
authors.affiliation: Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110 012, India. Electronic address: ssriari@gmail.com.
authors.forename: Surender
authors.initials: S
authors.lastname: Singh
authors.affiliation: Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110 012, India.
authors.forename: Rameshwar
authors.initials: R
authors.lastname: Tiwari
authors.affiliation: Central Instrumentation facility, University of Delhi, South Campus, Benito Juarez Road, New Delhi 110 021, India.
authors.forename: Renu
authors.initials: R
authors.lastname: Goel
authors.affiliation: Division of Microbiology, ICAR-Indian Agricultural Research Institute, New Delhi 110 012, India.
authors.forename: Lata
authors.initials: L
authors.lastname: Nain
mesh_terms: D001234:Aspergillus niger / Q000166:cytology / Q000201:enzymology; D002241:Carbohydrates / Q000737:chemistry; D044602:Cellulases / Q000737:chemistry* / Q000378:metabolism*; D018556:Crops, Agricultural / Q000737:chemistry; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism*; D005110:Extracellular Space / Q000201:enzymology; D005290:Ferric Compounds / Q000737:chemistry*; D020035:Holoenzymes / Q000737:chemistry / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D053758:Nanoparticles / Q000737:chemistry*; D013696:Temperature
chemical_list: D002241:Carbohydrates; D004800:Enzymes, Immobilized; D005290:Ferric Compounds; D020035:Holoenzymes; C000499:ferric oxide; D044602:Cellulases
keywords: Aspergillus niger; Extracellular proteome; Glycoside hydrolase; LC MS/MS; Proteomics; Solid-state fermentation