title: Combined alkali and hydrothermal pretreatments for oat straw valorization within a biorefinery concept.
abstract: The aim of this work was the evaluation of lime pretreatment combined or not with previous step of autohydrolysis for oat straw valorization. Under selected conditions of lime pretreatment, 96% of glucan and 77% of xylan were recovered and 42% of delignification was achieved. Xylose fermentation to ethanol by metabolic engineered Saccharomyces cerevisiae (MEC1133) strain improved the ethanol production by 22% achieving 41g/L. Alternatively, first step of autohydrolysis (S0=4.22) allowed a high oligosaccharides recovery (68%) and subsequent lime pretreatment attained a 57% of delignification and 99% of glucan to glucose conversion. Oat straw processed by autohydrolysis and lime pretreatment reached the maximal ethanol concentration (50g/L). Both strategies led to oat straw valorization into bioethanol, oligosaccharides and lignin indicating that these pretreatments are adequate as a first stage within an oat straw biorefinery.
authors: CEB-Centre of Biological Engineering, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; Department of Chemical Engineering, Faculty of Science, University of Vigo (Campus Ourense), As Lagoas, 32004 Ourense, Spain.
authors: Aloia
authors: A
authors: Romaní
authors: Department of Chemical Engineering, Faculty of Science, University of Vigo (Campus Ourense), As Lagoas, 32004 Ourense, Spain.
authors: Pablo D
authors: PD
authors: Tomaz
authors: Department of Chemical Engineering, Faculty of Science, University of Vigo (Campus Ourense), As Lagoas, 32004 Ourense, Spain; CITI-Tecnopole, San Ciprián das Viñas, 32901 Ourense, Spain.
authors: Gil
authors: G
authors: Garrote
authors: CEB-Centre of Biological Engineering, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal.
authors: José A
authors: JA
authors: Teixeira
authors: CEB-Centre of Biological Engineering, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal. Electronic address: luciliad@deb.uminho.pt.
authors: Lucília
authors: L
authors: Domingues
mesh_terms: D000468:Alkalies / Q000737:chemistry* / Q000378:metabolism; D018554:Avena / Q000737:chemistry* / Q000378:metabolism; D017610:Calcium Compounds / Q000737:chemistry; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D006868:Hydrolysis; D008031:Lignin / Q000378:metabolism; D060847:Metabolic Engineering; D009844:Oligosaccharides / Q000737:chemistry / Q000378:metabolism; D010087:Oxides / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D014994:Xylose / Q000378:metabolism
chemical_list: D000468:Alkalies; D017610:Calcium Compounds; D009844:Oligosaccharides; D010087:Oxides; D011134:Polysaccharides; D000431:Ethanol; C007916:hemicellulose; D008031:Lignin; D014994:Xylose; C016538:lime; D005947:Glucose
keywords: Autohydrolysis; Bioethanol; Biorefinery; Lime pretreatment; Oat straw