title: Lignocellulose conversion for biofuel: a new pretreatment greatly improves downstream biocatalytic hydrolysis of various lignocellulosic materials.
abstract: BACKGROUND
  Lignocellulosic biomass is an attractive renewable resource for future liquid transport fuel. Efficient and cost-effective production of bioethanol from lignocellulosic biomass depends on the development of a suitable pretreatment system. The aim of this study is to investigate a new pretreatment method that is highly efficient and effective for downstream biocatalytic hydrolysis of various lignocellulosic biomass materials, which can accelerate bioethanol commercialization.
  
  
  RESULTS
  The optimal conditions for the hydrogen peroxide-acetic acid (HPAC) pretreatment were 80 °C, 2 h, and an equal volume mixture of H2O2 and CH3COOH. Compared to organo-solvent pretreatment under the same conditions, the HPAC pretreatment was more effective at increasing enzymatic digestibility. After HPAC treatment, the composition of the recovered solid was 74.0 % cellulose, 20.0 % hemicelluloses, and 0.9 % lignin. Notably, 97.2 % of the lignin was removed with HPAC pretreatment. Fermentation of the hydrolyzates by S. cerevisiae resulted in 412 mL ethanol kg(-1) of biomass after 24 h, which was equivalent to 85.0 % of the maximum theoretical yield (based on the amount of glucose in the raw material).
  
  
  CONCLUSIONS
  The newly developed HPAC pretreatment was highly effective for removing lignin from lignocellulosic cell walls, resulting in enhanced enzymatic accessibility of the substrate and more efficient cellulose hydrolysis. This pretreatment produced less amounts of fermentative inhibitory compounds. In addition, HPAC pretreatment enables year-round operations, maximizing utilization of lignocellulosic biomass from various plant sources.
authors.affiliation: Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757 Republic of Korea.
authors.forename: Seung Gon
authors.initials: SG
authors.lastname: Wi
authors.affiliation: Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757 Republic of Korea.
authors.forename: Eun Jin
authors.initials: EJ
authors.lastname: Cho
authors.affiliation: Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757 Republic of Korea.
authors.forename: Dae-Seok
authors.initials: DS
authors.lastname: Lee
authors.affiliation: Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757 Republic of Korea.
authors.forename: Soo Jung
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Gwangju Center, Korea Basic Science Institute, Gwangju, 500-757 Republic of Korea.
authors.forename: Young Ju
authors.initials: YJ
authors.lastname: Lee
authors.affiliation: Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757 Republic of Korea.|Department of Bioenergy Science and Technology, Chonnam National University, Gwangju, 500-757 Republic of Korea.
authors.forename: Hyeun-Jong
authors.initials: HJ
authors.lastname: Bae
keywords: Bioethanol; Energy efficiency; Lignocellulosic biomass; Pretreatment