title: Hemp hurds biorefining: A path to green L-(+)-lactic acid production.
abstract: Sugars streams generated by organosolv pretreatment of hemp hurds, cellulose (C6) and hemicellulose (C5) fractions, were fermented to lactic acid (LA) by Bacillus coagulans strains XZL4 and DSM1. Pretreatment conditions and enzymatic hydrolysis were optimized and B. coagulans aptness to use lignocellulosic-derived sugars as a carbon source was evaluated. Methanolic organosolv pretreatment with 2.5% (w/w) H2SO4 gave the best results in terms of glucan recovery (98%), enzymatic hydrolysis of pretreated biomass (70%) and hemicellulosic sugars recovery (61%). C6 and C5 sugars fermentation by strain XZL4 gave, high LA yields (0.90 and 0.84 g/g), high titers (141 and 109 g/L), and high enantiomeric excess (>99%). Overall, 42 g of l-LA were obtained from 100 g of raw hemp hurds. These results can be considered promising for lignocellulosic feedstock valorization toward the production of polymer-grade LA.
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare (ICRM), Consiglio Nazioneale delle Ricerche (CNR), Via Mario Bianco 9, 20131 Milano, Italy; The Protein Factory, Centro Interuniversitario di Biotecnologie Proteiche, Università degli Studi dell'Insubria, Politecnico di Milano, ICRM CNR, Milano, Italy. Electronic address: stefano.gandolfi@icrm.cnr.it.
authors.forename: Stefano
authors.initials: S
authors.lastname: Gandolfi
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare (ICRM), Consiglio Nazioneale delle Ricerche (CNR), Via Mario Bianco 9, 20131 Milano, Italy; The Protein Factory, Centro Interuniversitario di Biotecnologie Proteiche, Università degli Studi dell'Insubria, Politecnico di Milano, ICRM CNR, Milano, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Pistone
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare (ICRM), Consiglio Nazioneale delle Ricerche (CNR), Via Mario Bianco 9, 20131 Milano, Italy; The Protein Factory, Centro Interuniversitario di Biotecnologie Proteiche, Università degli Studi dell'Insubria, Politecnico di Milano, ICRM CNR, Milano, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Ottolina
authors.affiliation: Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
authors.forename: Ping
authors.initials: P
authors.lastname: Xu
authors.affiliation: Istituto di Chimica del Riconoscimento Molecolare (ICRM), Consiglio Nazioneale delle Ricerche (CNR), Via Mario Bianco 9, 20131 Milano, Italy; The Protein Factory, Centro Interuniversitario di Biotecnologie Proteiche, Università degli Studi dell'Insubria, Politecnico di Milano, ICRM CNR, Milano, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Riva
mesh_terms: D001407:Bacillus / Q000378:metabolism; D018533:Biomass; D002188:Cannabis / Q000378:metabolism*; D002241:Carbohydrates; D002482:Cellulose / Q000378:metabolism; D005285:Fermentation / Q000502:physiology; D006868:Hydrolysis; D019344:Lactic Acid / Q000378:metabolism*; D008031:Lignin / Q000378:metabolism; D011108:Polymers / Q000378:metabolism; D011134:Polysaccharides / Q000378:metabolism
chemical_list: D002241:Carbohydrates; D011108:Polymers; D011134:Polysaccharides; C036909:lignocellulose; D019344:Lactic Acid; C007916:hemicellulose; D002482:Cellulose; D008031:Lignin
keywords: Biomass conversion; Biorefineries; Hemp hurds; Lactic acid; Organosolv