Biochemical characterization and synergism of cellulolytic enzyme system from Chaetomium globosum on rice straw saccharification. Issue 1 (December 2016)

• Record Type: Journal Article
• Authors: Wanmolee, Wanwitoo; Sornlake, Warasirin; Rattanaphan, Nakul; Suwannarangsee, Surisa; Laosiripojana, Navadol; Champreda, Verawat
• Is Part Of: BMC biotechnology. Volume 16:Issue 1(2016)
• Page Start: 1
• Page End: 12
• Publication Date: 2016-12
• Subjects: Cellulase -- Chaetomium globosum -- Lignocellulose -- Saccharification -- Synergistic action; Biotechnology -- Periodicals; 660.605
• DOI: 10.1186/s12896-016-0312-7
• Languages: English
• ISSNs: 1472-6750

Abstract

Abstract Background Efficient hydrolysis of lignocellulosic materials to sugars for conversion to biofuels and chemicals is a key step in biorefinery. Designing an active saccharifying enzyme system with synergy among their components is considered a promising approach. Results In this study, a lignocellulose-degrading enzyme system ofChaetomium globosum BCC5776 (CG-Cel) was characterized for its activity and proteomic profiles, and synergism with accessory enzymes. The highest cellulase productivity of 0.40 FPU/mL was found for CG-Cel under the optimized submerged fermentation conditions on 1% (w/v) EPFB (empty palm fruit bunch), 2% microcrystalline cellulose (Avicel®) and 1% soybean meal (SBM) at 30 °C, pH 5.8 for 6 d. CG-Cel worked optimally at 50–60 °C in an acidic pH range. Proteomics analysis by LC/MS/MS revealed a complex enzyme system composed of core cellulases and accessory hydrolytic/non-hydrolytic enzymes attacking plant biopolymers. A synergistic enzyme system comprising the CG-Cel, a β-glucosidase (Novozyme® 188) and a hemicellulase Accellerase® XY was optimized on saccharification of alkaline-pretreated rice straw by a mixture design approach. Applying a full cubic model, the optimal ratio of ternary enzyme mixture containing CG-Cel: Novozyme® 188: Accellerase® XY of 44.4:20.6:35.0 showed synergistic enhancement on reducing sugar yield with a glucose releasing efficiency of 256.4 mg/FPU, equivalent to a 2.9 times compared with that from CG-Cel alone. Conclusions The work showed an approach for developing an active synergistic enzyme system based on the newly characterizedC. globosum for lignocellulose saccharification and modification in bio-industries.