451
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Li C, Wang L, Chen Z, Li Y, Wang R, Luo X, Cai G, Li Y, Yu Q, Lu J. Ozonolysis pretreatment of maize stover: the interactive effect of sample particle size and moisture on ozonolysis process. BIORESOURCE TECHNOLOGY 2015; 183:240-247. [PMID: 25746300 DOI: 10.1016/j.biortech.2015.01.042] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/06/2015] [Accepted: 01/09/2015] [Indexed: 06/04/2023]
Abstract
Maize stover was ozonolyzed to improve the enzymatic digestibility. The interactive effect of sample particle size and moisture content on ozonolysis was studied. After ozonolysis, both lignin and xylan decreased while cellulose was only slightly affected in all experiments. It was also found that the smaller particle size is better for ozonolysis. The similar water activity of the different optimum moisture contents for ozonolysis reveals that the free and bound water ratio is a key factor of ozonolysis. The best result of ozonolysis was obtained at the mesh of -300 and the moisture of 60%, where up to 75% lignin was removed. The glucose yield after enzymatic hydrolysis increased from 18.5% to 80%. Water washing had low impact on glucose yield (less than 10% increases), but significantly reduced xylose yield (up to 42% decreases). The result indicates that ozonolysis leads to xylan solubilization.
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Affiliation(s)
- Cheng Li
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Li Wang
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China.
| | - Zhengxing Chen
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Yongfu Li
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Ren Wang
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Xiaohu Luo
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Guolin Cai
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Yanan Li
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Qiusheng Yu
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China
| | - Jian Lu
- State Key Laboratory of Food Science and Technology, National Engineering Laboratory for Cereal Fermentation Technology, and Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of Education, Jiangnan University, Wuxi 214122, People's Republic of China
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452
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Chen HZ, Liu ZH. Steam explosion and its combinatorial pretreatment refining technology of plant biomass to bio-based products. Biotechnol J 2015; 10:866-85. [DOI: 10.1002/biot.201400705] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 02/13/2015] [Accepted: 03/25/2015] [Indexed: 11/09/2022]
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453
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Molecular dynamics simulations of large macromolecular complexes. Curr Opin Struct Biol 2015; 31:64-74. [PMID: 25845770 DOI: 10.1016/j.sbi.2015.03.007] [Citation(s) in RCA: 264] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 03/13/2015] [Accepted: 03/16/2015] [Indexed: 12/11/2022]
Abstract
Connecting dynamics to structural data from diverse experimental sources, molecular dynamics simulations permit the exploration of biological phenomena in unparalleled detail. Advances in simulations are moving the atomic resolution descriptions of biological systems into the million-to-billion atom regime, in which numerous cell functions reside. In this opinion, we review the progress, driven by large-scale molecular dynamics simulations, in the study of viruses, ribosomes, bioenergetic systems, and other diverse applications. These examples highlight the utility of molecular dynamics simulations in the critical task of relating atomic detail to the function of supramolecular complexes, a task that cannot be achieved by smaller-scale simulations or existing experimental approaches alone.
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454
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Kinetics of enzymatic hydrolysis of rice straw by the pretreatment with a bio-based basic ionic liquid under ultrasound. Process Biochem 2015. [DOI: 10.1016/j.procbio.2015.01.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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455
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Identification of glycosyl hydrolases from a metagenomic library of microflora in sugarcane bagasse collection site and their cooperative action on cellulose degradation. J Biosci Bioeng 2015; 119:384-91. [DOI: 10.1016/j.jbiosc.2014.09.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 08/12/2014] [Accepted: 09/13/2014] [Indexed: 11/19/2022]
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456
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Cha YL, Yang J, Park Y, An GH, Ahn JW, Moon YH, Yoon YM, Yu GD, Choi IH. Continuous alkaline pretreatment of Miscanthus sacchariflorus using a bench-scale single screw reactor. BIORESOURCE TECHNOLOGY 2015; 181:338-344. [PMID: 25681689 DOI: 10.1016/j.biortech.2015.01.079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 01/17/2015] [Accepted: 01/19/2015] [Indexed: 06/04/2023]
Abstract
Miscanthus sacchariflorus 'Goedae-Uksae 1' (GU) was developed as an energy crop of high productivity in Korea. For the practical use of GU for bioethanol production, a bench-scale continuous pretreatment system was developed. The reactor performed screw extrusion, soaking and thermochemical pretreatment at the following operating conditions: 3 mm particle size, 22% moisture content, 140 °C reaction temperature, 8 min residence time, 15 g/min biomass feeding and 120 mL/min NaOH input. As a result of minimizing NaOH concentration and enzyme dosage, 90.8±0.49% glucose yield was obtained from 0.5 M NaOH-pretreated GU containing 3% glucan with 10 FPU cellulase/g cellulose at 50 °C for 72 h. The separate hydrolysis and fermentation of 0.5 M NaOH-pretreated GU containing 10% glucan with 10-30 FPU for 102 h produced 43.0-49.6 g/L bioethanol (theoretical yield, 75.8-87.6%). Thus, this study demonstrated that continuous pretreatment using a single screw reactor is effective for bioethanol production from Miscanthus biomass.
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Affiliation(s)
- Young-Lok Cha
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan-ro 199, Muan 534-833, Republic of Korea
| | - Jungwoo Yang
- School of Life Sciences and Biotechnology for BK21 PLUS, Korea University, Seoul 136-713, Republic of Korea.
| | - Yuri Park
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan-ro 199, Muan 534-833, Republic of Korea
| | - Gi Hong An
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan-ro 199, Muan 534-833, Republic of Korea
| | - Jong-Woong Ahn
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan-ro 199, Muan 534-833, Republic of Korea
| | - Youn-Ho Moon
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan-ro 199, Muan 534-833, Republic of Korea
| | - Young-Mi Yoon
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan-ro 199, Muan 534-833, Republic of Korea
| | - Gyeong-Dan Yu
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan-ro 199, Muan 534-833, Republic of Korea
| | - In-Hu Choi
- Bioenergy Crop Research Institute, National Institute of Crop Science, Rural Development Administration, Muan-ro 199, Muan 534-833, Republic of Korea
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457
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Surendra K, Sawatdeenarunat C, Shrestha S, Sung S, Khanal SK. Anaerobic Digestion-Based Biorefinery for Bioenergy and Biobased Products. Ind Biotechnol (New Rochelle N Y) 2015. [DOI: 10.1089/ind.2015.0001] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- K.C. Surendra
- Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, Honolulu, HI
| | - Chayanon Sawatdeenarunat
- Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, Honolulu, HI
| | - Shilva Shrestha
- Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, Honolulu, HI
| | - Shihwu Sung
- College of Agriculture, Forestry and Natural Resource Management, University of Hawai'i at Hilo, Hilo, HI
| | - Samir Kumar Khanal
- Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, Honolulu, HI
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458
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Challenges for the production of bioethanol from biomass using recombinant yeasts. ADVANCES IN APPLIED MICROBIOLOGY 2015; 92:89-125. [PMID: 26003934 DOI: 10.1016/bs.aambs.2015.02.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Lignocellulose biomass, one of the most abundant renewable resources on the planet, is an alternative sustainable energy source for the production of second-generation biofuels. Energy in the form of simple or complex carbohydrates can be extracted from lignocellulose biomass and fermented by microorganisms to produce bioethanol. Despite 40 years of active and cutting-edge research invested into the development of technologies to produce bioethanol from lignocellulosic biomass, the process remains commercially unviable. This review describes the achievements that have been made in generating microorganisms capable of utilizing both simple and complex sugars from lignocellulose biomass and the fermentation of these sugars into ethanol. We also provide a discussion on the current "roadblocks" standing in the way of making second-generation bioethanol a commercially viable alternative to fossil fuels.
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459
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Zhao X, Tang J, Wang X, Yang R, Zhang X, Gu Y, Li X, Ma M. YNL134C from Saccharomyces cerevisiae encodes a novel protein with aldehyde reductase activity for detoxification of furfural derived from lignocellulosic biomass. Yeast 2015; 32:409-22. [PMID: 25656244 DOI: 10.1002/yea.3068] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 12/28/2014] [Accepted: 01/28/2015] [Indexed: 02/03/2023] Open
Abstract
Furfural and 5-hydroxymethylfurfural (HMF) are the two main aldehyde compounds derived from pentoses and hexoses, respectively, during lignocellulosic biomass pretreatment. These two compounds inhibit microbial growth and interfere with subsequent alcohol fermentation. Saccharomyces cerevisiae has the in situ ability to detoxify furfural and HMF to the less toxic 2-furanmethanol (FM) and furan-2,5-dimethanol (FDM), respectively. Herein, we report that an uncharacterized gene, YNL134C, was highly up-regulated under furfural or HMF stress and Yap1p and Msn2/4p transcription factors likely controlled its up-regulated expression. Enzyme activity assays showed that YNL134C is an NADH-dependent aldehyde reductase, which plays a role in detoxification of furfural to FM. However, no NADH- or NADPH-dependent enzyme activity was observed for detoxification of HMF to FDM. This enzyme did not catalyse the reverse reaction of FM to furfural or FDM to HMF. Further studies showed that YNL134C is a broad-substrate aldehyde reductase, which can reduce multiple aldehydes to their corresponding alcohols. Although YNL134C is grouped into the quinone oxidoreductase family, no quinone reductase activity was observed using 1,2-naphthoquinone or 9,10-phenanthrenequinone as a substrate, and phylogenetic analysis indicates that it is genetically distant to quinone reductases. Proteins similar to YNL134C in sequence from S. cerevisiae and other microorganisms were phylogenetically analysed.
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Affiliation(s)
- Xianxian Zhao
- Institute of Ecological and Environmental Sciences, College of Resources and Environmental Sciences, Sichuan Agricultural University, Wenjiang, Sichuan, People's Republic of China
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460
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Gao F, Gao L, Zhang D, Ye N, Chen S, Li D. Enhanced hydrolysis of Macrocystis pyrifera by integrated hydroxyl radicals and hot water pretreatment. BIORESOURCE TECHNOLOGY 2015; 179:490-496. [PMID: 25575209 DOI: 10.1016/j.biortech.2014.12.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 12/11/2014] [Accepted: 12/12/2014] [Indexed: 05/23/2023]
Abstract
Integrated hydroxyl radicals and hot water pretreatment (IHRHW) was employed in the bioconversion of the brown macroalgae Macrocystis pyrifera (M. pyrifera) in this study. The optimum experimental pretreatment condition (100°C, 30 min, 11.9 mM FeSO4) and the predicted optimum pretreatment condition (113.95°C, 29.1 min, 12.75 mM FeSO4) were identified using a central composite design method. All glucan and xylan were recovered as monosaccharides or polysaccharides without a fermentation inhibitor (e.g., hydroxymethyl furfural and furfural). The IHRHW-treated macroalgae digestibility reached 88.1% under the optimum experimental condition, whereas that under the predicted optimum condition reached 92.1%. The value was approximately threefold higher than those obtained with untreated M. pyrifera. Carbohydrate recovery and enzymatic hydrolysis can be significantly enhanced by the new economic hydroxyl radicals and hot water pretreatment.
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Affiliation(s)
- Feng Gao
- Tianjin Key Laboratory for Industrial BioSystems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Le Gao
- Tianjin Key Laboratory for Industrial BioSystems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Dongyuan Zhang
- Tianjin Key Laboratory for Industrial BioSystems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Naihao Ye
- Key Laboratory for Sustainable Utilization of Marine Fishery Resources, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
| | - Shulin Chen
- Tianjin Key Laboratory for Industrial BioSystems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Demao Li
- Tianjin Key Laboratory for Industrial BioSystems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.
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461
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Yang M, Kuittinen S, Zhang J, Vepsäläinen J, Keinänen M, Pappinen A. Co-fermentation of hemicellulose and starch from barley straw and grain for efficient pentoses utilization in acetone-butanol-ethanol production. BIORESOURCE TECHNOLOGY 2015; 179:128-135. [PMID: 25536510 DOI: 10.1016/j.biortech.2014.12.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/01/2014] [Accepted: 12/03/2014] [Indexed: 06/04/2023]
Abstract
This study aims to efficiently use hemicellulose-based biomass for ABE (acetone-butanol-ethanol) production by co-fermentation with starch-based biomass. Two processes were investigated: (I) co-fermentation of sugars derived from hemicellulose and starch in a mixture of barley straw and grain that was pretreated with dilute acid; (II) co-fermentation of straw hemicellulosic hydrolysate and gelatinized grain slurry in which the straw was pretreated with dilute acid. The two processes produced 11.3 and 13.5 g/L ABE that contains 7.4 and 7.8 g/L butanol, respectively. In process I, pretreatment with 1.0% H2SO4 resulted in better ABE fermentability than with 1.5% H2SO4, but only 19% of pentoses were consumed. In process II, 95% of pentoses were utilized even in the hemicellulosic hydrolysate pretreated with more severe condition (1.5% H2SO4). The results suggest that process II is more favorable for hemicellulosic biomass utilization, and it is also attractive for sustainable biofuel production due to great biomass availability.
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Affiliation(s)
- Ming Yang
- School of Forest Sciences, University of Eastern Finland, P.O. Box 111, FI80101 Joensuu, Finland.
| | - Suvi Kuittinen
- School of Forest Sciences, University of Eastern Finland, P.O. Box 111, FI80101 Joensuu, Finland
| | - Junhua Zhang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, 712100 Yangling, China
| | - Jouko Vepsäläinen
- School of Pharmacy, University of Eastern Finland, P.O. Box 1627, FI70211 Kuopio, Finland
| | - Markku Keinänen
- Department of Biology, University of Eastern Finland, P.O. Box 111, FI80101 Joensuu, Finland
| | - Ari Pappinen
- School of Forest Sciences, University of Eastern Finland, P.O. Box 111, FI80101 Joensuu, Finland
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462
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Amore A, Parameswaran B, Kumar R, Birolo L, Vinciguerra R, Marcolongo L, Ionata E, La Cara F, Pandey A, Faraco V. Application of a new xylanase activity from Bacillus amyloliquefaciens XR44A in brewer's spent grain saccharification. JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY (OXFORD, OXFORDSHIRE : 1986) 2015; 90:573-581. [PMID: 25866429 PMCID: PMC4384805 DOI: 10.1002/jctb.4589] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 11/05/2014] [Accepted: 11/13/2014] [Indexed: 05/12/2023]
Abstract
BACKGROUND Cellulases and xylanases are the key enzymes involved in the conversion of lignocelluloses into fermentable sugars. Western Ghat region (India) has been recognized as an active hot spot for the isolation of new microorganisms. The aim of this work was to isolate new microorganisms producing cellulases and xylanases to be applied in brewer's spent grain saccharification. RESULTS 93 microorganisms were isolated from Western Ghat and screened for the production of cellulase and xylanase activities. Fourteen cellulolytic and seven xylanolytic microorganisms were further screened in liquid culture. Particular attention was focused on the new isolate Bacillus amyloliquefaciens XR44A, producing xylanase activity up to 10.5 U mL-1. A novel endo-1,4-beta xylanase was identified combining zymography and proteomics and recognized as the main enzyme responsible for B. amyloliquefaciens XR44A xylanase activity. The new xylanase activity was partially characterized and its application in saccharification of brewer's spent grain, pretreated by aqueous ammonia soaking, was investigated. CONCLUSION The culture supernatant of B. amyloliquefaciens XR44A with xylanase activity allowed a recovery of around 43% xylose during brewer's spent grain saccharification, similar to the value obtained with a commercial xylanase from Trichoderma viride, and a maximum arabinose yield of 92%, around 2-fold higher than that achieved with the commercial xylanase. © 2014 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Antonella Amore
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelovia Cintia, 4, 80126, Naples, Italy
| | - Binod Parameswaran
- CSIR-National Institute for Interdisciplinary Science and Technology (NIIST)Trivandrum, 695 019, India
| | - Ramesh Kumar
- CSIR-National Institute for Interdisciplinary Science and Technology (NIIST)Trivandrum, 695 019, India
| | - Leila Birolo
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelovia Cintia, 4, 80126, Naples, Italy
| | - Roberto Vinciguerra
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelovia Cintia, 4, 80126, Naples, Italy
| | - Loredana Marcolongo
- Institute of Biosciences and BioResources - National Research CouncilNapoli, Italy
| | - Elena Ionata
- Institute of Biosciences and BioResources - National Research CouncilNapoli, Italy
| | - Francesco La Cara
- Institute of Biosciences and BioResources - National Research CouncilNapoli, Italy
| | - Ashok Pandey
- CSIR-National Institute for Interdisciplinary Science and Technology (NIIST)Trivandrum, 695 019, India
| | - Vincenza Faraco
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelovia Cintia, 4, 80126, Naples, Italy
- * Correspondence to: V. Faraco, Department of Chemical Sciences, University of Naples “Federico II”, Complesso Universitario Monte S. Angelo, via Cintia, 4 80126 Napoli, Italy. E-mail:
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463
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Kim SK, Jin YS, Choi IG, Park YC, Seo JH. Enhanced tolerance of Saccharomyces cerevisiae to multiple lignocellulose-derived inhibitors through modulation of spermidine contents. Metab Eng 2015; 29:46-55. [PMID: 25724339 DOI: 10.1016/j.ymben.2015.02.004] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 01/06/2015] [Accepted: 02/17/2015] [Indexed: 01/13/2023]
Abstract
Fermentation inhibitors present in lignocellulose hydrolysates are inevitable obstacles for achieving economic production of biofuels and biochemicals by industrial microorganisms. Here we show that spermidine (SPD) functions as a chemical elicitor for enhanced tolerance of Saccharomyces cerevisiae against major fermentation inhibitors. In addition, the feasibility of constructing an engineered S. cerevisiae strain capable of tolerating toxic levels of the major inhibitors without exogenous addition of SPD was explored. Specifically, we altered expression levels of the genes in the SPD biosynthetic pathway. Also, OAZ1 coding for ornithine decarboxylase (ODC) antizyme and TPO1 coding for the polyamine transport protein were disrupted to increase intracellular SPD levels through alleviation of feedback inhibition on ODC and prevention of SPD excretion, respectively. Especially, the strain with combination of OAZ1 and TPO1 double disruption and overexpression of SPE3 not only contained spermidine content of 1.1mg SPD/g cell, which was 171% higher than that of the control strain, but also exhibited 60% and 33% shorter lag-phase period than that of the control strain under the medium containing furan derivatives and acetic acid, respectively. While we observed a positive correlation between intracellular SPD contents and tolerance phenotypes among the engineered strains accumulating different amounts of intracellular SPD, too much SPD accumulation is likely to cause metabolic burden. Therefore, genetic perturbations for intracellular SPD levels should be optimized in terms of metabolic burden and SPD contents to construct inhibitor tolerant yeast strains. We also found that the genes involved in purine biosynthesis and cell wall and chromatin stability were related to the enhanced tolerance phenotypes to furfural. The robust strains constructed in this study can be applied for producing chemicals and advanced biofuels from cellulosic hydrolysates.
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Affiliation(s)
- Sun-Ki Kim
- Department of Agricultural Biotechnology and Center for Food and Bioconvergence, Seoul National University, Seoul 151-921, Republic of Korea
| | - Yong-Su Jin
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - In-Geol Choi
- College of Life sciences and Biotechnology, Korea University, Seoul 136-713, Republic of Korea
| | - Yong-Cheol Park
- Department of Bio and Fermentation Convergence, Kookmin University, Seoul 136-702, Republic of Korea
| | - Jin-Ho Seo
- Department of Agricultural Biotechnology and Center for Food and Bioconvergence, Seoul National University, Seoul 151-921, Republic of Korea.
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464
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Jaeger V, Burney P, Pfaendtner J. Comparison of three ionic liquid-tolerant cellulases by molecular dynamics. Biophys J 2015; 108:880-892. [PMID: 25692593 PMCID: PMC4336362 DOI: 10.1016/j.bpj.2014.12.043] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 12/20/2014] [Accepted: 12/29/2014] [Indexed: 10/24/2022] Open
Abstract
We have employed molecular dynamics to investigate the differences in ionic liquid tolerance among three distinct family 5 cellulases from Trichoderma viride, Thermogata maritima, and Pyrococcus horikoshii. Simulations of the three cellulases were conducted at a range of temperatures in various binary mixtures of the ionic liquid 1-ethyl-3-methyl-imidazolium acetate with water. Our analysis demonstrates that the effects of ionic liquids on the enzymes vary in each individual case from local structural disturbances to loss of much of one of the enzyme's secondary structure. Enzymes with more negatively charged surfaces tend to resist destabilization by ionic liquids. Specific and unique structural changes in the enzymes are induced by the presence of ionic liquids. Disruption of the secondary structure, changes in dynamical motion, and local changes in the binding pocket are observed in less tolerant enzymes. Ionic-liquid-induced denaturation of one of the enzymes is indicated over the 500 ns timescale. In contrast, the most tolerant cellulase behaves similarly in water and in ionic-liquid-containing mixtures. Unlike the heuristic approaches that attempt to predict enzyme stability using macroscopic properties, molecular dynamics allows us to predict specific atomic-level structural and dynamical changes in an enzyme's behavior induced by ionic liquids and other mixed solvents. Using these insights, we propose specific experimentally testable hypotheses regarding the origin of activity loss for each of the systems investigated in this study.
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Affiliation(s)
- Vance Jaeger
- Department of Chemical Engineering, University of Washington, Seattle, Washington
| | - Patrick Burney
- Department of Chemical Engineering, University of Washington, Seattle, Washington
| | - Jim Pfaendtner
- Department of Chemical Engineering, University of Washington, Seattle, Washington.
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465
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de Cassia Pereira J, Paganini Marques N, Rodrigues A, Brito de Oliveira T, Boscolo M, da Silva R, Gomes E, Bocchini Martins D. Thermophilic fungi as new sources for production of cellulases and xylanases with potential use in sugarcane bagasse saccharification. J Appl Microbiol 2015; 118:928-39. [DOI: 10.1111/jam.12757] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 01/07/2015] [Accepted: 01/11/2015] [Indexed: 11/30/2022]
Affiliation(s)
- J. de Cassia Pereira
- Laboratory of Biochemistry and Applied Microbiology; São Paulo State University - UNESP/IBILCE; São José do Rio Preto São Paulo State Brazil
| | - N. Paganini Marques
- Laboratory of Microbial Enzymes; São Paulo State University - UNESP/IQ; Araraquara São Paulo State Brazil
| | - A. Rodrigues
- Laboratory of Ecology and Systematics of Fungi; São Paulo State University - IB/UNESP; Rio Claro São Paulo State Brazil
| | - T. Brito de Oliveira
- Laboratory of Ecology and Systematics of Fungi; São Paulo State University - IB/UNESP; Rio Claro São Paulo State Brazil
| | - M. Boscolo
- Laboratory of Sucrochemistry and Analytical Chemistry; São Paulo State University - IB/UNESP; Rio Claro São Paulo State Brazil
| | - R. da Silva
- Laboratory of Biochemistry and Applied Microbiology; São Paulo State University - UNESP/IBILCE; São José do Rio Preto São Paulo State Brazil
| | - E. Gomes
- Laboratory of Biochemistry and Applied Microbiology; São Paulo State University - UNESP/IBILCE; São José do Rio Preto São Paulo State Brazil
| | - D.A. Bocchini Martins
- Laboratory of Microbial Enzymes; São Paulo State University - UNESP/IQ; Araraquara São Paulo State Brazil
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466
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A dye-decolorizing peroxidase from Bacillus subtilis exhibiting substrate-dependent optimum temperature for dyes and β-ether lignin dimer. Sci Rep 2015; 5:8245. [PMID: 25650125 PMCID: PMC4316163 DOI: 10.1038/srep08245] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 12/19/2014] [Indexed: 11/17/2022] Open
Abstract
In the biorefinery using lignocellulosic biomass as feedstock, pretreatment to breakdown or loosen lignin is important step and various approaches have been conducted. For biological pretreatment, we screened Bacillus subtilis KCTC2023 as a potential lignin-degrading bacterium based on veratryl alcohol (VA) oxidation test and the putative heme-containing dye-decolorizing peroxidase was found in the genome of B. subtilis KCTC2023. The peroxidase from B. subtilis KCTC2023 (BsDyP) was capable of oxidizing various substrates and atypically exhibits substrate-dependent optimum temperature: 30°C for dyes (Reactive Blue19 and Reactive Black5) and 50°C for high redox potential substrates (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid [ABTS], VA, and veratryl glycerol-β-guaiacyl ether [VGE]) over +1.0 V vs. normal hydrogen electrode. At 50°C, optimum temperature for high redox potential substrates, BsDyP not only showed the highest VA oxidation activity (0.13 Umg−1) among the previously reported bacterial peroxidases but also successfully achieved VGE decomposition by cleaving Cα-Cβ bond in the absence of any oxidative mediator with a specific activity of 0.086 Umg−1 and a conversion rate of 53.5%. Based on our results, BsDyP was identified as the first bacterial peroxidase capable of oxidizing high redox potential lignin-related model compounds, especially VGE, revealing a previously unknown versatility of lignin degrading biocatalyst in nature.
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467
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Li X, Yu VY, Lin Y, Chomvong K, Estrela R, Park A, Liang JM, Znameroski EA, Feehan J, Kim SR, Jin YS, Glass NL, Cate JHD. Expanding xylose metabolism in yeast for plant cell wall conversion to biofuels. eLife 2015; 4. [PMID: 25647728 PMCID: PMC4338637 DOI: 10.7554/elife.05896] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 02/02/2015] [Indexed: 12/18/2022] Open
Abstract
Sustainable biofuel production from renewable biomass will require the efficient and complete use of all abundant sugars in the plant cell wall. Using the cellulolytic fungus Neurospora crassa as a model, we identified a xylodextrin transport and consumption pathway required for its growth on hemicellulose. Reconstitution of this xylodextrin utilization pathway in Saccharomyces cerevisiae revealed that fungal xylose reductases act as xylodextrin reductases, producing xylosyl-xylitol oligomers as metabolic intermediates. These xylosyl-xylitol intermediates are generated by diverse fungi and bacteria, indicating that xylodextrin reduction is widespread in nature. Xylodextrins and xylosyl-xylitol oligomers are then hydrolyzed by two hydrolases to generate intracellular xylose and xylitol. Xylodextrin consumption using a xylodextrin transporter, xylodextrin reductases and tandem intracellular hydrolases in cofermentations with sucrose and glucose greatly expands the capacity of yeast to use plant cell wall-derived sugars and has the potential to increase the efficiency of both first-generation and next-generation biofuel production. DOI:http://dx.doi.org/10.7554/eLife.05896.001 Plants can be used to make ‘biofuels’, which are more sustainable alternatives to traditional fuels made from petroleum. Unfortunately, most biofuels are currently made from simple sugars or starch extracted from parts of plants that we also use for food, such as the grains of cereal crops. Making biofuels from the parts of the plant that are not used for food—for example, the stems or leaves—would enable us to avoid a trade-off between food and fuel production. However, most of the sugars in these parts of the plant are locked away in the form of large, complex carbohydrates called cellulose and hemicellulose, which form the rigid cell wall surrounding each plant cell. Currently, the industrial processes that can be used to make biofuels from plant cell walls are expensive and use a lot of energy. They involve heating or chemically treating the plant material to release the cellulose and hemicellulose. Then, large quantities of enzymes are added to break these carbohydrates down into simple sugars that can then be converted into alcohol (a biofuel) by yeast. Fungi may be able to provide us with a better solution. Many species are able to grow on plants because they can break down cellulose and hemicellulose into simple sugars they can use for energy. If the genes involved in this process could be identified and inserted into yeast it may provide a new, cheaper method to make biofuels from plant cell walls. To address this challenge, Li et al. studied how the fungus Neurospora crassa breaks down hemicellulose. This study identified a protein that can transport molecules of xylodextrin—which is found in hemicellulose—into the cells of the fungus, and two enzymes that break down the xylodextrin to make simple sugars, using a previously unknown chemical intermediate. When Li et al. inserted the genes that make the transport protein and the enzymes into yeast, the yeast were able to use plant cell wall material to make simple sugars and convert these to alcohol. The yeast used more of the xylodextrin when they were grown with an additional source of energy, such as the sugars glucose or sucrose. Li et al.'s findings suggest that giving yeast the ability to break down hemicellulose has the potential to improve the efficiency of biofuel production. The next challenge will be to improve the process so that the yeast can convert the xylodextrin and simple sugars more rapidly. DOI:http://dx.doi.org/10.7554/eLife.05896.002
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Affiliation(s)
- Xin Li
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Vivian Yaci Yu
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Yuping Lin
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Kulika Chomvong
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, United States
| | - Raíssa Estrela
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Annsea Park
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Julie M Liang
- Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - Elizabeth A Znameroski
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Joanna Feehan
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Soo Rin Kim
- Institute for Genomic Biology, University of Illinois, Urbana, United States
| | - Yong-Su Jin
- Institute for Genomic Biology, University of Illinois, Urbana, United States
| | - N Louise Glass
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, United States
| | - Jamie H D Cate
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
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468
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Sawatdeenarunat C, Surendra KC, Takara D, Oechsner H, Khanal SK. Anaerobic digestion of lignocellulosic biomass: challenges and opportunities. BIORESOURCE TECHNOLOGY 2015; 178:178-186. [PMID: 25446783 DOI: 10.1016/j.biortech.2014.09.103] [Citation(s) in RCA: 238] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 09/19/2014] [Accepted: 09/20/2014] [Indexed: 05/19/2023]
Abstract
Anaerobic digestion (AD) of lignocellulosic biomass provides an excellent opportunity to convert abundant bioresources into renewable energy. Rumen microorganisms, in contrast to conventional microorganisms, are an effective inoculum for digesting lignocellulosic biomass due to their intrinsic ability to degrade substrate rich in cellulosic fiber. However, there are still several challenges that must be overcome for the efficient digestion of lignocellulosic biomass. Anaerobic biorefinery is an emerging concept that not only generates bioenergy, but also high-value biochemical/products from the same feedstock. This review paper highlights the current status of lignocellulosic biomass digestion and discusses its challenges. The paper also discusses the future research needs of lignocellulosic biomass digestion.
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Affiliation(s)
- Chayanon Sawatdeenarunat
- Department of Molecular Biosciences and Bioengineering (MBBE), University of Hawai'i at Mānoa, 1955 East-West Road, Agricultural Science Building 218, Honolulu, HI 96822, USA
| | - K C Surendra
- Department of Molecular Biosciences and Bioengineering (MBBE), University of Hawai'i at Mānoa, 1955 East-West Road, Agricultural Science Building 218, Honolulu, HI 96822, USA
| | - Devin Takara
- Department of Molecular Biosciences and Bioengineering (MBBE), University of Hawai'i at Mānoa, 1955 East-West Road, Agricultural Science Building 218, Honolulu, HI 96822, USA
| | - Hans Oechsner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstrasse 9, Stuttgart 70599, Germany
| | - Samir Kumar Khanal
- Department of Molecular Biosciences and Bioengineering (MBBE), University of Hawai'i at Mānoa, 1955 East-West Road, Agricultural Science Building 218, Honolulu, HI 96822, USA.
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469
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Ruile S, Schmitz S, Mönch-Tegeder M, Oechsner H. Degradation efficiency of agricultural biogas plants--a full-scale study. BIORESOURCE TECHNOLOGY 2015; 178:341-349. [PMID: 25453437 DOI: 10.1016/j.biortech.2014.10.053] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 10/09/2014] [Accepted: 10/10/2014] [Indexed: 06/04/2023]
Abstract
The degradation efficiency of 21 full-scale agricultural CSTR biogas plants was investigated. The residual methane potential of the digestion stages was determined in batch digestion tests (20.0 and 37.0 °C). The results of this study showed that the residual methane yield is significantly correlated to the HRT (r=-0.73). An almost complete degradation of the input substrates was achieved due to a HRT of more than 100 days (0.097±0.017 Nm(3)/kg VS). The feedstock characteristics have the largest impact to the degradation time. It was found that standard values of the methane yield are a helpful tool for evaluating the degradation efficiency. Adapting the HRT to the input materials is the key factor for an efficient degradation in biogas plants. No influence of digester series configuration to the VS degradation was found. The mean VS degradation rate in the total reactor systems was 78±7%.
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Affiliation(s)
- Stephan Ruile
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany.
| | - Sabine Schmitz
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Matthias Mönch-Tegeder
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Hans Oechsner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
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470
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Lindner J, Zielonka S, Oechsner H, Lemmer A. Effects of mechanical treatment of digestate after anaerobic digestion on the degree of degradation. BIORESOURCE TECHNOLOGY 2015; 178:194-200. [PMID: 25451773 DOI: 10.1016/j.biortech.2014.09.117] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 06/04/2023]
Abstract
The aim of this study was to increase the biogas production from different substrates by applying a mechanical treatment only to the non-degraded digestate after the fermentation process in order to feed it back into the process. To evaluate this approach, digestates were grounded with a ball mill for four different treatment time periods (0, 2, 5, 10 min) and then the effects on the particle size, volatile organic substances, methane yield and degradation kinetic were measured. A decrease of volatile fatty acids based on this treatment was not detected. The mechanical treatment caused in maximum to a triplication of the methane yield and to a quadruplicating of the daily methane production.
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Affiliation(s)
- Jonas Lindner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany.
| | - Simon Zielonka
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Hans Oechsner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
| | - Andreas Lemmer
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstraße 9, 70 599 Stuttgart, Germany
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471
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Enhanced ethanol production by fermentation of Gelidium amansii hydrolysate using a detoxification process and yeasts acclimated to high-salt concentration. Bioprocess Biosyst Eng 2015; 38:1201-7. [DOI: 10.1007/s00449-015-1362-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Accepted: 01/15/2015] [Indexed: 10/24/2022]
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472
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Ra CH, Kang CH, Jeong GT, Kim SK. Bioethanol production from the waste product of salted Undaria pinnatifida using laboratory and pilot development unit (PDU) scale fermenters. BIOTECHNOL BIOPROC E 2015. [DOI: 10.1007/s12257-014-0179-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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473
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Kim TY, Oh EJ, Jin YS, Oh MK. Improved resistance against oxidative stress of engineered cellobiose-fermenting Saccharomyces cerevisiae revealed by metabolite profiling. BIOTECHNOL BIOPROC E 2015. [DOI: 10.1007/s12257-014-0301-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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474
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Mohan M, Timung R, Deshavath NN, Banerjee T, Goud VV, Dasu VV. Optimization and hydrolysis of cellulose under subcritical water treatment for the production of total reducing sugars. RSC Adv 2015. [DOI: 10.1039/c5ra20319h] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Subcritical water (SCW) treatment has gained enormous attention as an environmentally friendly technique for organic matter and an attractive reaction medium for a variety of applications. In the current work the process parameters were optimized by RSM model.
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Affiliation(s)
- Mood Mohan
- Department of Chemical Engineering
- Indian Institute of Technology Guwahati
- Guwahati
- India
| | - Robinson Timung
- Department of Chemical Engineering
- Indian Institute of Technology Guwahati
- Guwahati
- India
| | | | - Tamal Banerjee
- Department of Chemical Engineering
- Indian Institute of Technology Guwahati
- Guwahati
- India
| | - Vaibhav V. Goud
- Department of Chemical Engineering
- Indian Institute of Technology Guwahati
- Guwahati
- India
- Centre for the Environment
| | - Venkata V. Dasu
- Centre for the Environment
- Indian Institute of Technology Guwahati
- Guwahati
- India
- Department of Biosciences and Bioengineering
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475
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Sharma AK, Kumar R, Mittal S, Hussain S, Arora M, Sharma RC, Babu JN. In situ reductive regeneration of zerovalent iron nanoparticles immobilized on cellulose for atom efficient Cr(vi) adsorption. RSC Adv 2015. [DOI: 10.1039/c5ra19917d] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
nZVI (11.8 ± 0.2% w/w) immobilized on microcrystalline cellulose (C-nZVI) shows unusual Cr(vi) adsorption (562.8 mg g−1 of nZVI) as a consequence of in situ regeneration of nZVI upon oxidation of cellulose to cellulose dialdehyde.
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Affiliation(s)
- Archana Kumari Sharma
- Centre for Environmental Science & Technology
- School of Environment and Earth Sciences
- Central University of Punjab
- Bathinda-151 001
- India
| | - Rabindra Kumar
- Centre for Environmental Science & Technology
- School of Environment and Earth Sciences
- Central University of Punjab
- Bathinda-151 001
- India
| | - Sunil Mittal
- Centre for Environmental Science & Technology
- School of Environment and Earth Sciences
- Central University of Punjab
- Bathinda-151 001
- India
| | - Shamima Hussain
- UGC-DAE Consortium for Scientific Research
- Kokilamedu-603 104
- India
| | - Meenu Arora
- Department of Chemistry
- Multani Mal Modi College
- Patiala
- India
| | - Ramesh Chand Sharma
- Centre for Environmental Science & Technology
- School of Environment and Earth Sciences
- Central University of Punjab
- Bathinda-151 001
- India
| | - J. Nagendra Babu
- Centre for Chemical Sciences
- School of Basic and Applied Sciences
- Central University of Punjab
- Bathinda-151 001
- India
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476
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477
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Isikgor FH, Becer CR. Lignocellulosic biomass: a sustainable platform for the production of bio-based chemicals and polymers. Polym Chem 2015. [DOI: 10.1039/c5py00263j] [Citation(s) in RCA: 1492] [Impact Index Per Article: 165.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The ongoing research activities in the field of lignocellulosic biomass for production of value-added chemicals and polymers that can be utilized to replace petroleum-based materials are reviewed.
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Affiliation(s)
| | - C. Remzi Becer
- School of Engineering and Materials Science
- Queen Mary University of London
- E1 4NS London
- UK
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478
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Liu R, Gao M, Zhang J, Li Z, Chen J, Liu P, Wu D. An ionic liquid promoted microwave-hydrothermal route towards highly photoluminescent carbon dots for sensitive and selective detection of iron(iii). RSC Adv 2015. [DOI: 10.1039/c5ra00089k] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Carbon dots with a high photoluminescence efficiency of ∼22.58% are obtained by a facile microwave-hydrothermal treatment of rice straw with the presence of ionic liquid.
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Affiliation(s)
- Ruili Liu
- Department of Chemical Engineering
- School of Environment and Chemical Engineering
- Shanghai University
- Shanghai 200444
- China
| | - Mengping Gao
- Department of Chemical Engineering
- School of Environment and Chemical Engineering
- Shanghai University
- Shanghai 200444
- China
| | - Jing Zhang
- Department of Chemical Engineering
- School of Environment and Chemical Engineering
- Shanghai University
- Shanghai 200444
- China
| | - Zhilian Li
- Department of Chemical Engineering
- School of Environment and Chemical Engineering
- Shanghai University
- Shanghai 200444
- China
| | - Jinyang Chen
- Department of Chemical Engineering
- School of Environment and Chemical Engineering
- Shanghai University
- Shanghai 200444
- China
| | - Ping Liu
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- China
| | - Dongqing Wu
- School of Chemistry and Chemical Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- China
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479
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Sharma S, Kumar R, Gaur R, Agrawal R, Gupta RP, Tuli DK, Das B. Pilot scale study on steam explosion and mass balance for higher sugar recovery from rice straw. BIORESOURCE TECHNOLOGY 2015; 175:350-7. [PMID: 25459842 DOI: 10.1016/j.biortech.2014.10.112] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 10/20/2014] [Accepted: 10/21/2014] [Indexed: 05/15/2023]
Abstract
Pretreatment of rice straw on pilot scale steam explosion has been attempted to achieve maximum sugar recovery. Three different reaction media viz. water, sulfuric acid and phosphoric acid (0.5%, w/w) were explored for pretreatment by varying operating temperature (160, 180 and 200°C) and reaction time (5 and 10min). Using water and 0.5% SA showed almost similar sugar recovery (∼87%) at 200 and 180°C respectively. However, detailed studies showed that the former caused higher production of oligomeric sugars (13.56g/L) than the later (3.34g/L). Monomeric sugar, followed the reverse trend (7.83 and 11.62g/L respectively). Higher oligomers have a pronounced effect in reducing enzymatic sugar yield as observed in case of water. Mass balance studies for water and SA assisted SE gave total saccharification yield as 81.8% and 77.1% respectively. However, techno-economical viability will have a trade-off between these advantages and disadvantages offered by the pretreatment medium.
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Affiliation(s)
- Sandeep Sharma
- DBT-IOC Centre for Advanced Bioenergy Research, Indian Oil Corporation Ltd., Research and Development Centre, Sector-13, Faridabad 121007, India
| | - Ravindra Kumar
- DBT-IOC Centre for Advanced Bioenergy Research, Indian Oil Corporation Ltd., Research and Development Centre, Sector-13, Faridabad 121007, India
| | - Ruchi Gaur
- DBT-IOC Centre for Advanced Bioenergy Research, Indian Oil Corporation Ltd., Research and Development Centre, Sector-13, Faridabad 121007, India
| | - Ruchi Agrawal
- DBT-IOC Centre for Advanced Bioenergy Research, Indian Oil Corporation Ltd., Research and Development Centre, Sector-13, Faridabad 121007, India
| | - Ravi P Gupta
- DBT-IOC Centre for Advanced Bioenergy Research, Indian Oil Corporation Ltd., Research and Development Centre, Sector-13, Faridabad 121007, India
| | - Deepak K Tuli
- DBT-IOC Centre for Advanced Bioenergy Research, Indian Oil Corporation Ltd., Research and Development Centre, Sector-13, Faridabad 121007, India.
| | - Biswapriya Das
- Indian Oil Corporation Ltd., Research and Development Centre, Sector-13, Faridabad 121007, India
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480
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Wi SG, Cho EJ, Lee DS, Lee SJ, Lee YJ, Bae HJ. Lignocellulose conversion for biofuel: a new pretreatment greatly improves downstream biocatalytic hydrolysis of various lignocellulosic materials. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:228. [PMID: 26705422 PMCID: PMC4690250 DOI: 10.1186/s13068-015-0419-4] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 12/15/2015] [Indexed: 05/11/2023]
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). CONCLUSION 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.
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Affiliation(s)
- Seung Gon Wi
- />Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757 Republic of Korea
| | - Eun Jin Cho
- />Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757 Republic of Korea
| | - Dae-Seok Lee
- />Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757 Republic of Korea
| | - Soo Jung Lee
- />Bio-Energy Research Center, Chonnam National University, Gwangju, 500-757 Republic of Korea
| | - Young Ju Lee
- />Gwangju Center, Korea Basic Science Institute, Gwangju, 500-757 Republic of Korea
| | - Hyeun-Jong Bae
- />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
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481
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Michelin M, Ruiz HA, Silva DP, Ruzene DS, Teixeira JA, Polizeli MLTM. Cellulose from Lignocellulosic Waste. POLYSACCHARIDES 2015. [DOI: 10.1007/978-3-319-16298-0_52] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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482
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Reactors for High Solid Loading Pretreatment of Lignocellulosic Biomass. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2015; 152:75-90. [PMID: 25757450 DOI: 10.1007/10_2015_307] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The review summarized the types, the geometry, and the design principle of pretreatment reactors at high solid loading of lignocellulose material. Among the reactors used, the explosion reactors and the helical stirring reactors are to be considered as the practical form for high solids loading pretreatment operation; the comminution reactors and the extruder reactors are difficult to be used as an independent unit, but possible to be used in the combined form with other types of reactors. The principles of the pretreatment reactor design at high solid loading were discussed and several basic principles for the design were proposed. This review provided useful information for choosing the reactor types and designing the geometry of pretreatment operation at the high solids loading.
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483
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Peng X, Qiao W, Mi S, Jia X, Su H, Han Y. Characterization of hemicellulase and cellulase from the extremely thermophilic bacterium Caldicellulosiruptor owensensis and their potential application for bioconversion of lignocellulosic biomass without pretreatment. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:131. [PMID: 26322125 PMCID: PMC4552416 DOI: 10.1186/s13068-015-0313-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 08/13/2015] [Indexed: 05/08/2023]
Abstract
BACKGROUND Pretreatment is currently the common approach for improving the efficiency of enzymatic hydrolysis on lignocellulose. However, the pretreatment process is expensive and will produce inhibitors such as furan derivatives and phenol derivatives. If the lignocellulosic biomass can efficiently be saccharified by enzymolysis without pretreatment, the bioconversion process would be simplified. The genus Caldicellulosiruptor, an obligatory anaerobic and extreme thermophile can produce a diverse set of glycoside hydrolases (GHs) for deconstruction of lignocellulosic biomass. It gives potential opportunities for improving the efficiency of converting native lignocellulosic biomass to fermentable sugars. RESULTS Both of the extracellular (extra-) and intracellular (intra-) enzymes of C. owensensis cultivated on corncob xylan or xylose had cellulase (including endoglucanase, cellobiohydrolase and β-glucosidase) and hemicellulase (including xylanase, xylosidase, arabinofuranosidase and acetyl xylan esterase) activities. The enzymes of C. owensensis had high ability for degrading hemicellulose of native corn stover and corncob with the conversion rates of xylan 16.7 % and araban 60.0 %. Moreover, they had remarkable synergetic function with the commercial enzyme cocktail Cellic CTec2 (Novoyzmes). When the native corn stover and corncob were respectively, sequentially hydrolyzed by the extra-enzymes of C. owensensis and CTec2, the glucan conversion rates were 31.2 and 37.9 %,which were 1.7- and 1.9-fold of each control (hydrolyzed by CTec2 alone), whereas the glucan conversion rates of the steam-exploded corn stover and corncob hydrolyzed by CTec2 alone on the same loading rate were 38.2 and 39.6 %, respectively. These results show that hydrolysis by the extra-enzyme of C. owensensis made almost the same contribution as steam-exploded pretreatment on degradation of native lignocellulosic biomass. A new process for saccharification of lignocellulosic biomass by sequential hydrolysis is demonstrated in the present research, namely hyperthermal enzymolysis (70-80 °C) by enzymes of C. owensensis followed with mesothermal enzymolysis (50-55 °C) by commercial cellulase. This process has the advantages of no sugar loss, few inhibitors generation and consolidated with sterilization. CONCLUSIONS The enzymes of C. owensensis demonstrated an enhanced ability to degrade the hemicellulose of native lignocellulose. The pretreatment and detoxification steps may be removed from the bioconversion process of the lignocellulosic biomass by using the enzymes from C. owensensis.
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Affiliation(s)
- Xiaowei Peng
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
| | - Weibo Qiao
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
| | - Shuofu Mi
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
| | - Xiaojing Jia
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
| | - Hong Su
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
| | - Yejun Han
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
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484
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Pereira SC, Maehara L, Machado CMM, Farinas CS. 2G ethanol from the whole sugarcane lignocellulosic biomass. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:44. [PMID: 25774217 PMCID: PMC4359543 DOI: 10.1186/s13068-015-0224-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 02/09/2015] [Indexed: 05/07/2023]
Abstract
BACKGROUND In the sugarcane industry, large amounts of lignocellulosic residues are generated, which includes bagasse, straw, and tops. The use of the whole sugarcane lignocellulosic biomass for the production of second-generation (2G) ethanol can be a potential alternative to contribute to the economic viability of this process. Here, we conducted a systematic comparative study of the use of the lignocellulosic residues from the whole sugarcane lignocellulosic biomass (bagasse, straw, and tops) from commercial sugarcane varieties for the production of 2G ethanol. In addition, the feasibility of using a mixture of these residues from a selected variety was also investigated. RESULTS The materials were pretreated with dilute acid and hydrolyzed with a commercial enzymatic preparation, after which the hydrolysates were fermented using an industrial strain of Saccharomyces cerevisiae. The susceptibility to enzymatic saccharification was higher for the tops, followed by straw and bagasse. Interestingly, the fermentability of the hydrolysates showed a different profile, with straw achieving the highest ethanol yields, followed by tops and bagasse. Using a mixture of the different sugarcane parts (bagasse-straw-tops, 1:1:1, in a dry-weight basis), it was possible to achieve a 55% higher enzymatic conversion and a 25% higher ethanol yield, compared to use of the bagasse alone. For the four commercial sugarcane varieties evaluated using the same experimental set of conditions, it was found that the variety of sugarcane was not a significant factor in the 2G ethanol production process. CONCLUSIONS Assessment of use of the whole lignocellulosic sugarcane biomass clearly showed that 2G ethanol production could be significantly improved by the combined use of bagasse, straw, and tops, when compared to the use of bagasse alone. The lower susceptibility to saccharification of sugarcane bagasse, as well as the lower fermentability of its hydrolysates, can be compensated by using it in combination with straw and tops (sugarcane trash). Furthermore, given that the variety was not a significant factor for the 2G ethanol production process within the four commercial sugarcane varieties evaluated here, agronomic features such as higher productivity and tolerance of soil and climate variations can be used as the criteria for variety selection.
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Affiliation(s)
| | - Larissa Maehara
- />Embrapa Instrumentation, Rua XV de Novembro 1452, 13560-970 São Carlos, SP Brazil
- />Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luiz, km 235, 13565-905 São Carlos, SP Brazil
| | | | - Cristiane Sanchez Farinas
- />Embrapa Instrumentation, Rua XV de Novembro 1452, 13560-970 São Carlos, SP Brazil
- />Graduate Program of Chemical Engineering, Federal University of São Carlos, Rodovia Washington Luiz, km 235, 13565-905 São Carlos, SP Brazil
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485
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van Kuijk S, Sonnenberg A, Baars J, Hendriks W, Cone J. Fungal treated lignocellulosic biomass as ruminant feed ingredient: A review. Biotechnol Adv 2015; 33:191-202. [DOI: 10.1016/j.biotechadv.2014.10.014] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 09/23/2014] [Accepted: 10/31/2014] [Indexed: 10/24/2022]
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486
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Neumüller KG, de Souza AC, van Rijn JHJ, Streekstra H, Gruppen H, Schols HA. Positional preferences of acetyl esterases from different CE families towards acetylated 4-O-methyl glucuronic acid-substituted xylo-oligosaccharides. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:7. [PMID: 25642285 PMCID: PMC4311478 DOI: 10.1186/s13068-014-0187-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 12/15/2014] [Indexed: 05/17/2023]
Abstract
BACKGROUND Acetylation of the xylan backbone restricts the hydrolysis of plant poly- and oligosaccharides by hemicellulolytic enzyme preparations to constituent monosaccharides. The positional preferences and deacetylation efficiencies of acetyl esterases from seven different carbohydrate esterase (CE) families towards different acetylated xylopyranosyl units (Xylp) - as present in 4-O-methyl-glucuronic acid (MeGlcA)-substituted xylo-oligosaccharides (AcUXOS) derived from Eucalyptus globulus - were monitored by (1)H NMR, using common conditions for biofuel production (pH 5.0, 50°C). RESULTS Differences were observed regarding the hydrolysis of 2-O, 3-O, and 2,3-di-O acetylated Xylp and 3-O acetylated Xylp 2-O substituted with MeGlcA. The acetyl esterases tested could be categorized in three groups having activities towards (i) 2-O and 3-O acetylated Xylp, (ii) 2-O, 3-O, and 2,3-di-O acetylated Xylp, and (iii) 2-O, 3-O, and 2,3-di-O acetylated Xylp, as well as 3-O acetylated Xylp 2-O substituted with MeGlcA at the non-reducing end. A high deacetylation efficiency of up to 83% was observed for CE5 and CE1 acetyl esterases. Positional preferences were observed towards 2,3-di-O acetylated Xylp (TeCE1, AnCE5, and OsCE6) or 3-O acetylated Xylp (CtCE4). CONCLUSIONS Different positional preferences, deacetylation efficiencies, and initial deacetylation rates towards 2-O, 3-O, and 2,3-di-O acetylated Xylp and 3-O acetylated Xylp 2-O substituted with MeGlcA were demonstrated for acetyl esterases from different CE families at pH 5.0 and 50°C. The data allow the design of optimal, deacetylating hemicellulolytic enzyme mixtures for the hydrolysis of non-alkaline-pretreated bioenergy feedstocks.
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Affiliation(s)
- Klaus G Neumüller
- />DSM Biotechnology Center, PO Box 1, 2600 MA Delft, The Netherlands
- />Laboratory of Food Chemistry, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands
| | | | - Jozef HJ van Rijn
- />DSM Biotechnology Center, PO Box 1, 2600 MA Delft, The Netherlands
| | - Hugo Streekstra
- />DSM Biotechnology Center, PO Box 1, 2600 MA Delft, The Netherlands
| | - Harry Gruppen
- />Laboratory of Food Chemistry, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands
| | - Henk A Schols
- />Laboratory of Food Chemistry, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands
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487
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Vermerris W, Abril A. Enhancing cellulose utilization for fuels and chemicals by genetic modification of plant cell wall architecture. Curr Opin Biotechnol 2014; 32:104-112. [PMID: 25531269 DOI: 10.1016/j.copbio.2014.11.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 11/24/2014] [Accepted: 11/28/2014] [Indexed: 01/10/2023]
Abstract
Cellulose from plant biomass can serve as a sustainable feedstock for fuels, chemicals and polymers that are currently produced from petroleum. In order to enhance economic feasibility, the efficiency of cell wall deconstruction needs to be enhanced. With the use of genetic and biotechnological approaches cell wall composition can be modified in such a way that interactions between the major cell wall polymers—cellulose, hemicellulosic polysaccharides and lignin—are altered. Some of the resulting plants are compromised in their growth and development, but this may be caused in part by the plant's overcompensation for metabolic perturbances. In other cases novel structures have been introduced in the cell wall without negative effects. The first field studies with engineered bioenergy crops look promising, while detailed structural analyses of cellulose synthase offer new opportunities to modify cellulose itself.
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Affiliation(s)
- Wilfred Vermerris
- Department of Microbiology & Cell Science, University of Florida, Gainesville, FL 32611, United States; University of Florida Genetics Institute, University of Florida, Gainesville, FL 32611, United States; Graduate Program in Plant Molecular & Cellular Biology, University of Florida, Gainesville, FL 32611, United States.
| | - Alejandra Abril
- University of Florida Genetics Institute, University of Florida, Gainesville, FL 32611, United States; Graduate Program in Plant Molecular & Cellular Biology, University of Florida, Gainesville, FL 32611, United States
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488
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Zhao L, Cao GL, Wang AJ, Ren HY, Zhang K, Ren NQ. Consolidated bioprocessing performance of Thermoanaerobacterium thermosaccharolyticum M18 on fungal pretreated cornstalk for enhanced hydrogen production. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:178. [PMID: 25648837 PMCID: PMC4296546 DOI: 10.1186/s13068-014-0178-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 12/03/2014] [Indexed: 06/01/2023]
Abstract
BACKGROUND Biological hydrogen production from lignocellulosic biomass shows great potential as a promising alternative to conventional hydrogen production methods, such as electrolysis of water and coal gasification. Currently, most researches on biohydrogen production from lignocellulose concentrate on consolidated bioprocessing, which has the advantages of simpler operation and lower cost over processes featuring dedicated cellulase production. However, the recalcitrance of the lignin structure induces a low cellulase activity, making the carbohydrates in the hetero-matrix more unapproachable. Pretreatment of lignocellulosic biomass is consequently an extremely important step in the commercialization of biohydrogen, and for massive realization of lignocellulosic biomass as alternative fuel feedstock. Thus, development of a pretreatment method which is cost efficient, environmentally benign, and highly efficient for enhanced consolidated bioprocessing of lignocellulosic biomass to hydrogen is essential. RESULTS In this research, fungal pretreatment was adopted for enhanced hydrogen production by consolidated bioprocessing performance. To confirm the fungal pretreatment efficiency, two typical thermochemical pretreatments were also compared side by side. Results showed that the fungal pretreatment was superior to the other pretreatments in terms of high lignin reduction of up to 35.3% with least holocellulose loss (the value was only 9.5%). Microscopic structure observation combined with Fourier transform infrared spectroscopy (FTIR) analysis further demonstrated that the lignin and crystallinity of lignocellulose were decreased with better holocellulose reservation. Upon fungal pretreatment, the hydrogen yield and hydrogen production rate were 6.8 mmol H2 g(-1) pretreated substrate and 0.89 mmol L(-1) h(-1), respectively, which were 2.9 and 4 times higher than the values obtained for the untreated sample. CONCLUSIONS Results revealed that although all pretreatments could contribute to the enhancement of hydrogen production from cornstalk, fungal pretreatment proved to be the optimal method. It is apparent that besides high hydrogen production efficiency, fungal pretreatment also offered several advantages over other pretreatments such as being environmentally benign and energy efficient. This pretreatment method thus has great potential for application in consolidated bioprocessing performance of hydrogen production.
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Affiliation(s)
- Lei Zhao
- />State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090 China
| | - Guang-Li Cao
- />State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090 China
- />School of Life Science and Technology, Harbin Institute of Technology, Harbin, 150090 China
| | - Ai-Jie Wang
- />State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090 China
| | - Hong-Yu Ren
- />State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090 China
| | - Kun Zhang
- />College of Power and Energy Engineering, Harbin Engineering University, Harbin, 150001 China
| | - Nan-Qi Ren
- />State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090 China
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489
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Nagoor Gunny AA, Arbain D, Mohamed Daud MZ, Jamal P. Synergistic action of deep eutectic solvents and cellulases for lignocellulosic biomass hydrolysis. ACTA ACUST UNITED AC 2014. [DOI: 10.1179/1432891714z.000000000933] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Affiliation(s)
- A. A. Nagoor Gunny
- School of Bioprocess EngineeringUniversiti Malaysia Perlis, Kompleks Pusat Pengajian Jejawi 3, 02600 Arau, Perlis, Malaysia
| | - D. Arbain
- School of Bioprocess EngineeringUniversiti Malaysia Perlis, Kompleks Pusat Pengajian Jejawi 3, 02600 Arau, Perlis, Malaysia
| | - M. Z. Mohamed Daud
- School of Bioprocess EngineeringUniversiti Malaysia Perlis, Kompleks Pusat Pengajian Jejawi 3, 02600 Arau, Perlis, Malaysia
| | - P. Jamal
- Bioenvironmental Engineering Research Unit (BERU)Department of Biotechnology Engineering, Faculty of Engineering, International Islamic University Malaysia, 50728 Gombak, Kuala Lumpur, Malaysia
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490
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Poovaiah CR, Nageswara-Rao M, Soneji JR, Baxter HL, Stewart CN. Altered lignin biosynthesis using biotechnology to improve lignocellulosic biofuel feedstocks. PLANT BIOTECHNOLOGY JOURNAL 2014; 12:1163-73. [PMID: 25051990 DOI: 10.1111/pbi.12225] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 05/30/2014] [Indexed: 05/19/2023]
Abstract
Lignocellulosic feedstocks can be converted to biofuels, which can conceivably replace a large fraction of fossil fuels currently used for transformation. However, lignin, a prominent constituent of secondary cell walls, is an impediment to the conversion of cell walls to fuel: the recalcitrance problem. Biomass pretreatment for removing lignin is the most expensive step in the production of lignocellulosic biofuels. Even though we have learned a great deal about the biosynthesis of lignin, we do not fully understand its role in plant biology, which is needed for the rational design of engineered cell walls for lignocellulosic feedstocks. This review will recapitulate our knowledge of lignin biosynthesis and discuss how lignin has been modified and the consequences for the host plant.
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Affiliation(s)
- Charleson R Poovaiah
- Department of Plant Sciences, University of Tennessee, Knoxville, TN, USA; Oak Ridge National Laboratory, BioEnergy Science Center, Oak Ridge, TN, USA
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491
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Al-Kaidy H, Duwe A, Huster M, Muffler K, Schlegel C, Sieker T, Stadtmüller R, Tippkötter N, Ulber R. Biotechnologie und Bioverfahrenstechnik - Vom ersten Ullmanns Artikel bis hin zu aktuellen Forschungsthemen. CHEM-ING-TECH 2014. [DOI: 10.1002/cite.201400083] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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492
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Isolation and identification of a cellulolytic bacterium from the Tibetan pig's intestine and investigation of its cellulase production. ELECTRON J BIOTECHN 2014. [DOI: 10.1016/j.ejbt.2014.08.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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493
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Naegele HJ, Mönch-Tegeder M, Haag NL, Oechsner H. Effect of substrate pretreatment on particle size distribution in a full-scale research biogas plant. BIORESOURCE TECHNOLOGY 2014; 172:396-402. [PMID: 25308908 DOI: 10.1016/j.biortech.2014.09.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 09/03/2014] [Accepted: 09/06/2014] [Indexed: 06/04/2023]
Abstract
The objective of this study was to investigate the pretreatment effects of high-fibre substrate on particle size distribution in a full-scale agricultural biogas plant (BGP). Two digesters, one fed with pretreated material and one with untreated material, were investigated for a period of 90days. Samples from different positions and heights were taken with a special probe sampling system and put through a wet sieve. The results show that on average 58.0±8.6% of the particles in both digesters are fine fraction (<0.063mm). A higher amount of particles (13.1%) with a length >4mm was measured in the untreated digester. However, the volume distribution over all positions and heights did not show a clear and uniform distribution of particles. These results reveal that substrate pretreatment has an effect on particle size in the fermenting substrate, but due to the uneven distribution mixing, is not homogeneous within the digester.
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Affiliation(s)
- Hans-Joachim Naegele
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstrasse 9, Stuttgart 70599, Germany.
| | - Matthias Mönch-Tegeder
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstrasse 9, Stuttgart 70599, Germany.
| | - Nicola Leonard Haag
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstrasse 9, Stuttgart 70599, Germany.
| | - Hans Oechsner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstrasse 9, Stuttgart 70599, Germany.
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494
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Purification and characterization of a hemocyanin (Hemo1) with potential lignin-modification activities from the wood-feeding termite, Coptotermes formosanus Shiraki. Appl Biochem Biotechnol 2014; 175:687-97. [PMID: 25342267 DOI: 10.1007/s12010-014-1326-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Accepted: 10/15/2014] [Indexed: 10/24/2022]
Abstract
Coptotermes formosanus Shiraki is a well-known wood-feeding termite, which can degrade not only cellulose and hemicellulose polysaccharides, but also some aromatic lignin polymers with its enzyme complex to the woody biomass. In this study, a very abundant protein was discovered and purified, using a three-step column chromatography procedure, from the tissue homogenate of the salivary glands and the gut of C. formosanus. Mass spectrometric analysis and the following peptide searching against the mRNA database toward this termite species indicated that the novel protein was a hemocyanin enzyme, termed as Hemo1, which further exhibited a strong oxidase activity in the substrate bioassays toward ABTS [2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)], as well as other aromatic analogues, such as catechol and veratryl alcohols. This oxidative protein was an acid-favored enzyme with a molecular weight at 82 kDa, and highly active at 80 °C. These findings indicated that the novel protein, hemocyanin, discovered from the gut system of C. formosanus, might be an important ligninolytic enzyme involved in the biomass pretreatment processing, which will potentially enhance the digestibility and utilization of biomass polysaccharides in termite digestive systems.
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495
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Singh J, Suhag M, Dhaka A. Augmented digestion of lignocellulose by steam explosion, acid and alkaline pretreatment methods: a review. Carbohydr Polym 2014; 117:624-631. [PMID: 25498680 DOI: 10.1016/j.carbpol.2014.10.012] [Citation(s) in RCA: 167] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 10/02/2014] [Accepted: 10/05/2014] [Indexed: 10/24/2022]
Abstract
Lignocellulosic materials can be explored as one of the sustainable substrates for bioethanol production through microbial intervention as they are abundant, cheap and renewable. But at the same time, their recalcitrant structure makes the conversion process more cumbersome owing to their chemical composition which adversely affects the efficiency of bioethanol production. Therefore, the technical approaches to overcome recalcitrance of biomass feedstock has been developed to remove the barriers with the help of pretreatment methods which make cellulose more accessible to the hydrolytic enzymes, secreted by the microorganisms, for its conversion to glucose. Pretreatment of lignocellulosic biomass in cost effective manner is a major challenge to bioethanol technology research and development. Hence, in this review, we have discussed various aspects of three commonly used pretreatment methods, viz., steam explosion, acid and alkaline, applied on various lignocellulosic biomasses to augment their digestibility alongwith the challenges associated with their processing.
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Affiliation(s)
- Joginder Singh
- Laboratory of Environmental Biotechnology, Department of Botany, A. I. Jat H. M. College, Rohtak 124001, Haryana, India.
| | - Meenakshi Suhag
- Institute of Environmental Studies, Kurukshetra University, Kurukshetra 136119, Haryana, India.
| | - Anil Dhaka
- PNRS Government College, Rohtak 124001, Haryana, India.
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496
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Monschein M, Reisinger C, Nidetzky B. Dissecting the effect of chemical additives on the enzymatic hydrolysis of pretreated wheat straw. BIORESOURCE TECHNOLOGY 2014; 169:713-722. [PMID: 25108473 DOI: 10.1016/j.biortech.2014.07.054] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Revised: 07/13/2014] [Accepted: 07/14/2014] [Indexed: 05/24/2023]
Abstract
Chemical additives were examined for ability to increase the enzymatic hydrolysis of thermo-acidically pretreated wheat straw by Trichoderma reesei cellulase at 50 °C. Semi-empirical descriptors derived from the hydrolysis time courses were applied to compare influence of these additives on lignocellulose bioconversion on a kinetic level, presenting a novel view on their mechanism of action. Focus was on rate retardation during hydrolysis, substrate conversion and enzyme adsorption. PEG 8000 enabled a reduction of enzyme loading by 50% while retaining the same conversion of 67% after 24h. For the first time, a beneficial effect of urea is reported, increasing the final substrate conversion after 48 h by 16%. The cationic surfactant cetyl-trimethylammonium bromide (CTAB) enhanced the hydrolysis rate at extended reaction time (rlim) by 34% and reduced reaction time by 28%. A combination of PEG 8000 and urea increased sugar release more than additives used individually.
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Affiliation(s)
- Mareike Monschein
- Austrian Centre of Industrial Biotechnology (ACIB), Petersgasse 14, 8010 Graz, Austria
| | - Christoph Reisinger
- CLARIANT Produkte (Deutschland) GmbH, Group Biotechnology, Staffelseestraße 6, 81477 Munich, Germany
| | - Bernd Nidetzky
- Austrian Centre of Industrial Biotechnology (ACIB), Petersgasse 14, 8010 Graz, Austria; Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 12/I, 8010 Graz, Austria.
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497
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Reduced power consumption compared to a traditional stirred tank reactor (STR) for enzymatic saccharification of alpha-cellulose using oscillatory baffled reactor (OBR) technology. Chem Eng Res Des 2014. [DOI: 10.1016/j.cherd.2014.01.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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498
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Xu H, Li B, Mu X, Yu G, Liu C, Zhang Y, Wang H. Quantitative characterization of the impact of pulp refining on enzymatic saccharification of the alkaline pretreated corn stover. BIORESOURCE TECHNOLOGY 2014; 169:19-26. [PMID: 25016462 DOI: 10.1016/j.biortech.2014.06.068] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 06/17/2014] [Accepted: 06/18/2014] [Indexed: 06/03/2023]
Abstract
In this work, corn stover was refined by a pulp refining instrument (PFI refiner) after NaOH pretreatment under varied conditions. The quantitative characterization of the influence of PFI refining on enzymatic hydrolysis was studied, and it was proved that the enhancement of enzymatic saccharification by PFI refining of the pretreated corn stover was largely due to the significant increment of porosity of substrates and the reduction of cellulose crystallinity. Furthermore, a linear relationship between beating degree and final total sugar yields was found, and a simple way to predict the final total sugar yields by easily testing the beating degree of PFI refined corn stover was established. Therefore, this paper provided the possibility and feasibility for easily monitoring the fermentable sugar production by the simple test of beating degree, and this will be of significant importance for the monitoring and controlling of industrial production in the future.
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Affiliation(s)
- Huanfei Xu
- CAS Key Laboratory of Bio-Based Material, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Bin Li
- CAS Key Laboratory of Bio-Based Material, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, People's Republic of China
| | - Xindong Mu
- CAS Key Laboratory of Bio-Based Material, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, People's Republic of China
| | - Guang Yu
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, People's Republic of China
| | - Chao Liu
- CAS Key Laboratory of Bio-Based Material, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, People's Republic of China
| | - Yuedong Zhang
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, People's Republic of China
| | - Haisong Wang
- CAS Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong 266101, People's Republic of China.
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499
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Electron beam irradiation and dilute alkali pretreatment for improving saccharification of rice straw. ACTA ACUST UNITED AC 2014. [DOI: 10.1007/s13765-014-4191-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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500
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Heins RA, Cheng X, Nath S, Deng K, Bowen BP, Chivian DC, Datta S, Friedland GD, D’Haeseleer P, Wu D, Tran-Gyamfi M, Scullin CS, Singh S, Shi W, Hamilton MG, Bendall ML, Sczyrba A, Thompson J, Feldman T, Guenther JM, Gladden JM, Cheng JF, Adams PD, Rubin EM, Simmons BA, Sale KL, Northen TR, Deutsch S. Phylogenomically guided identification of industrially relevant GH1 β-glucosidases through DNA synthesis and nanostructure-initiator mass spectrometry. ACS Chem Biol 2014; 9:2082-91. [PMID: 24984213 PMCID: PMC4168791 DOI: 10.1021/cb500244v] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Harnessing the biotechnological potential of the large number of proteins available in sequence databases requires scalable methods for functional characterization. Here we propose a workflow to address this challenge by combining phylogenomic guided DNA synthesis with high-throughput mass spectrometry and apply it to the systematic characterization of GH1 β-glucosidases, a family of enzymes necessary for biomass hydrolysis, an important step in the conversion of lignocellulosic feedstocks to fuels and chemicals. We synthesized and expressed 175 GH1s, selected from over 2000 candidate sequences to cover maximum sequence diversity. These enzymes were functionally characterized over a range of temperatures and pHs using nanostructure-initiator mass spectrometry (NIMS), generating over 10,000 data points. When combined with HPLC-based sugar profiling, we observed GH1 enzymes active over a broad temperature range and toward many different β-linked disaccharides. For some GH1s we also observed activity toward laminarin, a more complex oligosaccharide present as a major component of macroalgae. An area of particular interest was the identification of GH1 enzymes compatible with the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), a next-generation biomass pretreatment technology. We thus searched for GH1 enzymes active at 70 °C and 20% (v/v) [C2mim][OAc] over the course of a 24-h saccharification reaction. Using our unbiased approach, we identified multiple enzymes of different phylogentic origin with such activities. Our approach of characterizing sequence diversity through targeted gene synthesis coupled to high-throughput screening technologies is a broadly applicable paradigm for a wide range of biological problems.
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Affiliation(s)
- Richard A. Heins
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
- Sandia National
Laboratories, 7011 East Avenue, Livermore, California 94551, United States
| | - Xiaoliang Cheng
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Sangeeta Nath
- Joint Genome Institute, 2800 Mitchell Drive, Walnut
Creek, California 94598, United States
| | - Kai Deng
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Benjamin P. Bowen
- Lawrence Berkeley
National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
| | - Dylan C. Chivian
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Supratim Datta
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Gregory D. Friedland
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Patrik D’Haeseleer
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Dongying Wu
- Joint Genome Institute, 2800 Mitchell Drive, Walnut
Creek, California 94598, United States
| | - Mary Tran-Gyamfi
- Sandia National
Laboratories, 7011 East Avenue, Livermore, California 94551, United States
| | - Chessa S. Scullin
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Seema Singh
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
- Sandia National
Laboratories, 7011 East Avenue, Livermore, California 94551, United States
| | - Weibing Shi
- Joint Genome Institute, 2800 Mitchell Drive, Walnut
Creek, California 94598, United States
| | - Matthew G. Hamilton
- Joint Genome Institute, 2800 Mitchell Drive, Walnut
Creek, California 94598, United States
| | - Matthew L. Bendall
- Joint Genome Institute, 2800 Mitchell Drive, Walnut
Creek, California 94598, United States
| | - Alexander Sczyrba
- Joint Genome Institute, 2800 Mitchell Drive, Walnut
Creek, California 94598, United States
| | - John Thompson
- NIDCR, NIH, Oral
Infection and Immunity Branch, 30 Convent
Drive, Bethesda, Maryland 20892, United States
| | - Taya Feldman
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Joel M. Guenther
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - John M. Gladden
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
| | - Jan-Fang Cheng
- Joint Genome Institute, 2800 Mitchell Drive, Walnut
Creek, California 94598, United States
| | - Paul D. Adams
- Lawrence Berkeley
National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
| | - Edward M. Rubin
- Joint Genome Institute, 2800 Mitchell Drive, Walnut
Creek, California 94598, United States
- Lawrence Berkeley
National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
| | - Blake A. Simmons
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
- Sandia National
Laboratories, 7011 East Avenue, Livermore, California 94551, United States
| | - Kenneth L. Sale
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
- Sandia National
Laboratories, 7011 East Avenue, Livermore, California 94551, United States
| | - Trent R. Northen
- Joint Bioenergy
Institute, 5885 Hollis Street, Emeryville, California 94608, United States
- Lawrence Berkeley
National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
| | - Samuel Deutsch
- Joint Genome Institute, 2800 Mitchell Drive, Walnut
Creek, California 94598, United States
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