title: Fed-Batch Enzymatic Saccharification of High Solids Pretreated Lignocellulose for Obtaining High Titers and High Yields of Glucose.
abstract: To reduce the distillation costs of cellulosic ethanol, it is necessary to produce high sugar titers in the enzymatic saccharification step. To obtain high sugar titers, high biomass loadings of lignocellulose are necessary. In this study, to overcome the low saccharification yields and the low operability of high biomass loadings, a fed-batch saccharification process was developed using an enzyme reactor that was designed and built in-house. After optimizing the cellulase and biomass feeding profiles and the agitation speed, 132.6 g/L glucose and 76.0% theoretical maximum glucose were obtained from the 60 h saccharification of maleic acid-pretreated rice straw at a 30% (w/v) solids loading with 15 filter paper units (FPU) of Cellic CTec2/g glucan. This study demonstrated that through the proper optimization of fed-batch saccharification, both high sugar titers and high saccharification yields are possible, even with using the high solids loading (i.e., ≥30%) with the moderate enzyme loading (i.e., <15 FPU/g glucan). These results could be contributed to improving economic feasibility of the high solids saccharification process in cellulosic fuel and chemical production.
authors.affiliation: School of Food Science and Biotechnology, Kyungpook National University, Daegu, 41566, South Korea.
authors.forename: Young Hoon
authors.initials: YH
authors.lastname: Jung
authors.affiliation: Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea.
authors.forename: Hyun Min
authors.initials: HM
authors.lastname: Park
authors.affiliation: Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea.
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea.
authors.forename: Jungwoo
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea. khekim@korea.ac.kr.
authors.forename: Kyoung Heon
authors.initials: KH
authors.lastname: Kim
mesh_terms: D018533:Biomass; D002480:Cellulase / Q000737:chemistry*; D005947:Glucose / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008031:Lignin / Q000737:chemistry*; D008298:Maleates / Q000737:chemistry*; D012275:Oryza / Q000737:chemistry*
chemical_list: D008298:Maleates; C036909:lignocellulose; D008031:Lignin; C030272:maleic acid; D002480:Cellulase; D005947:Glucose
keywords: Cellulase; Fed-batch; High solids loading; Lignocellulose; Saccharification