title: Cellulase production from spent lignocellulose hydrolysates by recombinant Aspergillus niger.
abstract: A recombinant Aspergillus niger strain expressing the Hypocrea jecorina endoglucanase Cel7B was grown on spent hydrolysates (stillage) from sugarcane bagasse and spruce wood. The spent hydrolysates served as excellent growth media for the Cel7B-producing strain, A. niger D15[egI], which displayed higher endoglucanase activities in the spent hydrolysates than in standard medium with a comparable monosaccharide content (e.g., 2,100 nkat/ml in spent bagasse hydrolysate compared to 480 nkat/ml in standard glucose-based medium). In addition, A. niger D15[egI] was also able to consume or convert other lignocellulose-derived compounds, such as acetic acid, furan aldehydes, and phenolic compounds, which are recognized as inhibitors of yeast during ethanolic fermentation. The results indicate that enzymes can be produced from the stillage stream as a high-value coproduct in second-generation bioethanol plants in a way that also facilitates recirculation of process water.
authors.affiliation: Department of Chemistry and Biomedical Sciences, Karlstad University, Karlstad, Sweden.
authors.forename: Björn
authors.initials: B
authors.lastname: Alriksson
authors.forename: Shaunita H
authors.initials: SH
authors.lastname: Rose
authors.forename: Willem H
authors.initials: WH
authors.lastname: van Zyl
authors.forename: Anders
authors.initials: A
authors.lastname: Sjöde
authors.forename: Nils-Olof
authors.initials: NO
authors.lastname: Nilvebrant
authors.forename: Leif J
authors.initials: LJ
authors.lastname: Jönsson
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D001234:Aspergillus niger / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D002480:Cellulase / Q000235:genetics / Q000378:metabolism*; D005663:Furans / Q000378:metabolism; D035901:Hypocrea / Q000201:enzymology / Q000235:genetics; D008031:Lignin / Q000378:metabolism*; D010636:Phenols / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D005663:Furans; D010636:Phenols; D011994:Recombinant Proteins; C036909:lignocellulose; D008031:Lignin; D002480:Cellulase; D019342:Acetic Acid; C039281:furan