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Yi Y, Jin X, Chen M, Coldea TE, Zhao H. Surfactant-mediated bio-manufacture: A unique strategy for promoting microbial biochemicals production. Biotechnol Adv 2024; 73:108373. [PMID: 38704106 DOI: 10.1016/j.biotechadv.2024.108373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 04/03/2024] [Accepted: 05/01/2024] [Indexed: 05/06/2024]
Abstract
Biochemicals are widely used in the medicine and food industries and are more efficient and safer than synthetic chemicals. The amphipathic surfactants can interact with the microorganisms and embed the extracellular metabolites, which induce microbial metabolites secretion and biosynthesis, performing an attractive prospect of promoting the biochemical production. However, the commonness and differences of surfactant-mediated bio-manufacture in various fields are largely unexplored. Accordingly, this review comprehensively summarized the properties of surfactants, different application scenarios of surfactant-meditated bio-manufacture, and the mechanism of surfactants increasing metabolites production. Various biochemical productions such as pigments, amino acids, and alcohols could be enhanced using the cloud point and the micelles of surfactants. Besides, the amphiphilicity of surfactants also promoted the utilization of fermentation substrates, especially lignocellulose and waste sludge, by microorganisms, indirectly increasing the metabolites production. The increase in target metabolites production was attributed to the surfactants changing the permeability and composition of the cell membrane, hence improving the secretion ability of microorganisms. Moreover, surfactants could regulate the energy metabolism, the redox state and metabolic flow in microorganisms, which induced target metabolites synthesis. This review aimed to broaden the application fields of surfactants and provide novel insights into the production of microbial biochemicals.
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Affiliation(s)
- Yunxin Yi
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Xiaofan Jin
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Moutong Chen
- Guangdong Provincial Key Laboratory of Microbial Safety and Health, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Teodora Emilia Coldea
- Faculty of Food Science and Technology, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Cluj-Napoca 400372, Romania
| | - Haifeng Zhao
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, China; Research Institute for Food Nutrition and Human Health, Guangzhou 510640, China.
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2
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Velvizhi G, Jacqueline PJ, Shetti NP, K L, Mohanakrishna G, Aminabhavi TM. Emerging trends and advances in valorization of lignocellulosic biomass to biofuels. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 345:118527. [PMID: 37429092 DOI: 10.1016/j.jenvman.2023.118527] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/25/2023] [Accepted: 06/25/2023] [Indexed: 07/12/2023]
Abstract
Sustainable technologies pave the way to address future energy demand by converting lignocellulosic biomass into fuels, carbon-neutral materials, and chemicals which might replace fossil fuels. Thermochemical and biochemical technologies are conventional methods that convert biomass into value-added products. To enhance biofuel production, the existing technologies should be upgraded using advanced processes. In this regard, the present review explores the advanced technologies of thermochemical processes such as plasma technology, hydrothermal treatment, microwave-based processing, microbial-catalyzed electrochemical systems, etc. Advanced biochemical technologies such as synthetic metabolic engineering and genomic engineering have led to the development of an effective strategy to produce biofuels. The microwave-plasma-based technique increases the biofuel conversion efficiency by 97% and the genetic engineering strains increase the sugar production by 40%, inferring that the advanced technologies enhances the efficiency. So understanding these processes leads to low-carbon technologies which can solve the global issues on energy security, the greenhouse gases emission, and global warming.
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Affiliation(s)
- G Velvizhi
- CO(2) Research and Green Technology Centre, Vellore Institute of Technology (VIT), Vellore, 632 014, Tamil Nadu, India.
| | - P Jennita Jacqueline
- CO(2) Research and Green Technology Centre, Vellore Institute of Technology (VIT), Vellore, 632 014, Tamil Nadu, India; School of Chemical Engineering, Vellore Institute of Technology (VIT), Vellore, 632 014, Tamil Nadu, India
| | - Nagaraj P Shetti
- Center for Energy and Environment, School of Advanced Sciences, KLE Technological University, Hubballi, 580 031, Karnataka, India
| | - Latha K
- Department of Mathematics, Easwari Engineering College, Chennai, 600 089, Tamil Nadu, India
| | - Gunda Mohanakrishna
- Center for Energy and Environment, School of Advanced Sciences, KLE Technological University, Hubballi, 580 031, Karnataka, India
| | - Tejraj M Aminabhavi
- Center for Energy and Environment, School of Advanced Sciences, KLE Technological University, Hubballi, 580 031, Karnataka, India; School of Engineering, UPES, Bidholi, Dehradun, Uttarakhand 248 007, India.
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3
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Kadhum HJ, Mahapatra DM, Murthy GS. A comparative account of glucose yields and bioethanol production from separate and simultaneous saccharification and fermentation processes at high solids loading with variable PEG concentration. BIORESOURCE TECHNOLOGY 2019; 283:67-75. [PMID: 30901590 DOI: 10.1016/j.biortech.2019.03.060] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/09/2019] [Accepted: 03/11/2019] [Indexed: 06/09/2023]
Abstract
A process strategy to aid in optimal enzymatic hydrolysis through the addition of polyethylene glycol (PEG6000) was tested for separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). Pretreated wheat straw at 30% solids (w/w) loading was enzymatically hydrolyzed with 0, 0.5, 1, 1.5, 2 and 2.5% of PEG6000 through SHF and SSF. During SHF, bioethanol concentration of 107.5 g/L (2.5% PEG6000) was achieved. SSF ethanol concentration were about 113 g/L at 1.5% PEG6000 addition. A technoeconomic feasibility showed a return on investment (ROI) of 8.13% using 0.5% PEG6000 for SHF (96 h) and 12.25% ROI for SSF control (72 h). Life cycle assessment for the various scenarios indicated higher environmental gains for best cases of SSF over SHF. The study shows the SSF approach (0% PEG6000; 72 h) facilitates higher process efficiencies; technoeconomic gains and high environmental sustainability for future scale-up and commercial realization.
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Affiliation(s)
- Haider Jawad Kadhum
- Department of Biological and Ecological Engineering, Oregon State University, Corvallis, OR 97331, United States; College of Agriculture, Al-Qasim Green University, Babylon, Iraq.
| | - Durga Madhab Mahapatra
- Department of Biological and Ecological Engineering, Oregon State University, Corvallis, OR 97331, United States.
| | - Ganti S Murthy
- Department of Biological and Ecological Engineering, Oregon State University, Corvallis, OR 97331, United States.
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4
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Obeng EM, Budiman C, Ongkudon CM. Identifying additives for cellulase enhancement—A systematic approach. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2017. [DOI: 10.1016/j.bcab.2017.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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5
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Li X, Zheng Y. Lignin-enzyme interaction: Mechanism, mitigation approach, modeling, and research prospects. Biotechnol Adv 2017; 35:466-489. [DOI: 10.1016/j.biotechadv.2017.03.010] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 02/19/2017] [Accepted: 03/23/2017] [Indexed: 01/23/2023]
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6
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Chen C, Zhu M, Li M, Fan Y, Sun RC. Epoxidation and etherification of alkaline lignin to prepare water-soluble derivatives and its performance in improvement of enzymatic hydrolysis efficiency. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:87. [PMID: 27087854 PMCID: PMC4832561 DOI: 10.1186/s13068-016-0499-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 04/01/2016] [Indexed: 05/29/2023]
Abstract
BACKGROUND Due to the depletion of fossil resources and their environmental impact, woody biomass has received much attention as an alternative resource. Lignin, as the third most abundant biopolymer from biomass, is now considered as an excellent alternative feedstock for chemicals and materials. The conversion of lignin to the value-added products is a key process to achieve an integrated biorefinery of woody biomass. Among these value-added products, lignin-based derivatives with good surface activity can be applied to enhance the conversion of cellulose into fermentable sugars, which not only decrease the cost of bioethanol production, but also reduce the environmental pollution and green house effect resulting from the burning of fossil resources. RESULTS Water-soluble alkaline lignin was synthesized by the reaction between polyethylene glycols (PEG600 and PEG1000) and epoxy lignin. FT-IR and NMR analyses indicated that PEGs were successively introduced into epoxy alkaline lignin using potassium persulfate as a catalyst. Emulsification and surface activity tests indicated that the surface tension of the prepared lignin derivative solution was 43.30 mN/m at the critical micelle concentration (1.03 %). A stable emulsions layer was formed with hexanes and the emulsion particle diameter in the emulsion phase for all products was observed at 10-50 μm. The results of enzymatic hydrolysis indicated that the products derived from PEG1000-grafted lignin resulted in the highest increasing rate of 18.6 % of glucose yield during the enzymatic hydrolysis of hardwood bleached pulp. The results of fermentation experiments suggested that the product had no toxicity for fermentation micro-organisms. CONCLUSION Water-soluble alkaline lignin derivatives were prepared through epoxidation and etherification, which are promising feedstocks for detergents, emulsifier, and additive to enhance enzymatic hydrolysis efficiency and ethanol fermentation.
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Affiliation(s)
- Changzhou Chen
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
| | - Mingqiang Zhu
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
- />College of Forestry, Northwest A&F University, Yangling, 712100 China
| | - Mingfei Li
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
| | - Yongming Fan
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
| | - Run-Cang Sun
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
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Lin HN, Hu BB, Zhu MJ. Enhanced hydrogen production and sugar accumulation from spent mushroom compost by Clostridium thermocellum supplemented with PEG8000 and JFC-E. INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 2016; 41:2383-2390. [DOI: 10.1016/j.ijhydene.2015.11.078] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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8
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Fritz C, Ferrer A, Salas C, Jameel H, Rojas OJ. Interactions between Cellulolytic Enzymes with Native, Autohydrolysis, and Technical Lignins and the Effect of a Polysorbate Amphiphile in Reducing Nonproductive Binding. Biomacromolecules 2015; 16:3878-88. [DOI: 10.1021/acs.biomac.5b01203] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Consuelo Fritz
- Department
of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina 27695-8005, United States
| | - Ana Ferrer
- Department
of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina 27695-8005, United States
| | - Carlos Salas
- Department
of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina 27695-8005, United States
| | - Hasan Jameel
- Department
of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina 27695-8005, United States
| | - Orlando J. Rojas
- Department
of Forest Biomaterials, North Carolina State University, Raleigh, North Carolina 27695-8005, United States
- Bio-Based
Colloids and Materials, Department of Forest Products Technology and
Centre of Excellence on “Molecular Engineering of Biosynthetic
Hybrid Materials” (HYBER), Aalto University, FIN-00076 Aalto, Espoo, Finland
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9
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Lee KM, Kim KY, Choi O, Woo HM, Kim Y, Han SO, Sang BI, Um Y. In situ detoxification of lignocellulosic hydrolysate using a surfactant for butyric acid production by Clostridium tyrobutyricum ATCC 25755. Process Biochem 2015. [DOI: 10.1016/j.procbio.2015.01.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Hsieh CWC, Cannella D, Jørgensen H, Felby C, Thygesen LG. Cellobiohydrolase and endoglucanase respond differently to surfactants during the hydrolysis of cellulose. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:52. [PMID: 25829946 PMCID: PMC4379714 DOI: 10.1186/s13068-015-0242-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 03/19/2015] [Indexed: 05/29/2023]
Abstract
BACKGROUND Non-ionic surfactants such as polyethylene glycol (PEG) can increase the glucose yield obtained from enzymatic saccharification of lignocellulosic substrates. Various explanations behind this effect include the ability of PEG to increase the stability of the cellulases, decrease non-productive cellulase adsorption to the substrate, and increase the desorption of enzymes from the substrate. Here, using lignin-free model substrates, we propose that PEG also alters the solvent properties, for example, water, leading the cellulases to increase hydrolysis yields. RESULTS The effect of PEG differs for the individual cellulases. During hydrolysis of Avicel and PASC with a processive monocomponent exo-cellulase cellobiohydrolase (CBH) I, the presence of PEG leads to an increase in the final glucose concentration, while PEG caused no change in glucose production with a non-processive endoglucanase (EG). Also, no effect of PEG was seen on the activity of β-glucosidases. While PEG has a small effect on the thermostability of both cellulases, only the activity of CBH I increases with PEG. Using commercial enzyme mixtures, the hydrolysis yields increased with the addition of PEG. In parallel, we observed that the relaxation time of the hydrolysis liquid phase, as measured by LF-NMR, directly correlated with the final glucose yield. PEG was able to boost the glucose production even in highly concentrated solutions of up to 150 g/L of glucose. CONCLUSIONS The hydrolysis boosting effect of PEG appears to be specific for CBH I. The mechanism could be due to an increase in the apparent activity of the enzyme on the substrate surface. The addition of PEG increases the relaxation time of the liquid-phase water, which from the data presented points towards a mechanism related to PEG-water interactions rather than PEG-protein or PEG-substrate interactions.
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Affiliation(s)
- Chia-wen C Hsieh
- />Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, DK-1958 Frederiksberg C, Denmark
| | - David Cannella
- />Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, DK-1958 Frederiksberg C, Denmark
| | - Henning Jørgensen
- />Present address: Center for Bioprocess Engineering, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Building 229, DK-2800 Kgs. Lyngby, Denmark
| | - Claus Felby
- />Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, DK-1958 Frederiksberg C, Denmark
| | - Lisbeth G Thygesen
- />Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, DK-1958 Frederiksberg C, Denmark
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11
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Jiang H, Han B, Ge J. Enhancement in the enzymatic digestibility of hybrid poplar with poor residual hemicelluloses after Na2SO3 pretreatment. BIORESOURCE TECHNOLOGY 2015; 180:338-344. [PMID: 25621727 DOI: 10.1016/j.biortech.2014.12.103] [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: 11/13/2014] [Revised: 12/30/2014] [Accepted: 12/31/2014] [Indexed: 06/04/2023]
Abstract
The aim of this work was to illustrate the contributions of delignification and the introduced sulfonic groups on the enzymatic digestibility of the Na2SO3-pretreated hybrid poplar with poor residual hemicelluloses (HPPRH). The higher the content of the introduced sulfonic group in the pretreated HPPRH was, the higher its enzymatic digestibility could be achieved. Delignification was favorable to increasing the content of sulfonic group in the pretreated HPPRH. The introduced sulfonic group contributed much more to the total glucose yield at low level of residual lignin. The introduced sulfonic groups could contribute 17.30% of total glucose yield (92.70%) and delignification could do 38.43% of it. Meanwhile, the delignification rate and the sulfonic group content in the pretreated HPRH were 59.88% and 283.51mmolkg(-1) lignin, respectively. Therefore, the sulfonic group introduced on the pretreated lignocellulosics could improve the enzymatic digestibility and make the sulfite process effective.
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Affiliation(s)
- Hua Jiang
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China.
| | - Binbin Han
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Jianhong Ge
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
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12
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Dhiman SS, Haw JR, Kalyani D, Kalia VC, Kang YC, Lee JK. Simultaneous pretreatment and saccharification: green technology for enhanced sugar yields from biomass using a fungal consortium. BIORESOURCE TECHNOLOGY 2015; 179:50-57. [PMID: 25514402 DOI: 10.1016/j.biortech.2014.11.059] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 11/12/2014] [Accepted: 11/13/2014] [Indexed: 06/04/2023]
Abstract
Two different biomasses were subjected to simultaneous pretreatment and saccharification (SPS) using a cocktail of hydrolytic and oxidizing enzymes. Application of a novel laccase as a detoxifying agent caused the removal of 49.8% and 32.6% of phenolic contents from the soaked rice straw and willow, respectively. Hydrolysis of soaked substrates using a newly developed fungal consortium resulted in saccharification yield of up to 74.2% and 63.6% for rice straw and willow, respectively. A high saccharification yield was obtained with soaked rice straw and willow without using any hazardous chemicals. The efficiency of each step related to SPS was confirmed by atomic force microscopy. The suitability of the developed SPS process was further confirmed by converting the hydrolysate from the process into bioethanol with 72.4% sugar conversion efficiency. To the best of our knowledge, this is the first report on the development of a less tedious, single-pot, and eco-friendly SPS methodology.
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Affiliation(s)
- Saurabh Sudha Dhiman
- Department of Chemical Engineering, Konkuk University, 1 Hwayang-Dong, Gwangjin-Gu, Seoul 143-701, Republic of Korea; Institute of SK-KU Biomaterials, Konkuk University, 1 Hwayang-Dong, Gwangjin-Gu, Seoul 143-701, Republic of Korea
| | - Jung-Rim Haw
- Institute of SK-KU Biomaterials, Konkuk University, 1 Hwayang-Dong, Gwangjin-Gu, Seoul 143-701, Republic of Korea
| | - Dayanand Kalyani
- Department of Chemical Engineering, Konkuk University, 1 Hwayang-Dong, Gwangjin-Gu, Seoul 143-701, Republic of Korea
| | - Vipin C Kalia
- Microbial Biotechnology and Genomics, CSIR-Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India
| | - Yun Chan Kang
- Department of Materials Science and Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136-713, Republic of Korea
| | - Jung-Kul Lee
- Department of Chemical Engineering, Konkuk University, 1 Hwayang-Dong, Gwangjin-Gu, Seoul 143-701, Republic of Korea; Institute of SK-KU Biomaterials, Konkuk University, 1 Hwayang-Dong, Gwangjin-Gu, Seoul 143-701, Republic of Korea.
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13
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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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Hanly TJ, Henson MA. Dynamic model-based analysis of furfural and HMF detoxification by pure and mixed batch cultures of S. cerevisiae and S. stipitis. Biotechnol Bioeng 2013; 111:272-84. [PMID: 23983023 DOI: 10.1002/bit.25101] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 08/13/2013] [Accepted: 08/15/2013] [Indexed: 01/16/2023]
Abstract
Inhibitory compounds that result from biomass hydrolysis are an obstacle to the efficient production of second-generation biofuels. Fermentative microorganisms can reduce compounds such as furfural and 5-hydroxymethyl furfural (HMF), but detoxification is accompanied by reduced growth rates and ethanol yields. In this study, we assess the effects of these furan aldehydes on pure and mixed yeast cultures consisting of a respiratory deficient mutant of Saccharomyces cerevisiae and wild-type Scheffersomyces stipitis using dynamic flux balance analysis. Uptake kinetics and stoichiometric equations for the intracellular reduction reactions associated with each inhibitor were added to genome-scale metabolic reconstructions of the two yeasts. Further modification of the S. cerevisiae metabolic network was necessary to satisfactorily predict the amount of acetate synthesized during HMF reduction. Inhibitory terms that captured the adverse effects of the furan aldehydes and their corresponding alcohols on cell growth and ethanol production were added to attain qualitative agreement with batch experiments conducted for model development and validation. When the two yeasts were co-cultured in the presence of the furan aldehydes, inoculums that reduced the synthesis of highly toxic acetate produced by S. cerevisiae yielded the highest ethanol productivities. The model described here can be used to generate optimal fermentation strategies for the simultaneous detoxification and fermentation of lignocellulosic hydrolysates by S. cerevisiae and/or S. stipitis.
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Affiliation(s)
- Timothy J Hanly
- Department of Chemical Engineering, University of Massachusetts, Goessmann Lab 159, 686 N. Pleasant St., Amherst, Massachusetts, 01003-3110
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15
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A Review of the Role of Amphiphiles in Biomass to Ethanol Conversion. APPLIED SCIENCES-BASEL 2013. [DOI: 10.3390/app3020396] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Eckard AD, Muthukumarappan K, Gibbons W. Enzyme recycling in a simultaneous and separate saccharification and fermentation of corn stover: a comparison between the effect of polymeric micelles of surfactants and polypeptides. BIORESOURCE TECHNOLOGY 2013; 132:202-209. [PMID: 23411449 DOI: 10.1016/j.biortech.2013.01.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 12/30/2012] [Accepted: 01/04/2013] [Indexed: 06/01/2023]
Abstract
The efficacy of enzyme recycling in simultaneous (SSF) and separate (SHF) saccharification and fermentation of corn stover was evaluated with the use of novel enzyme stabilizers of casein, Tween20 and polymeric micelles (PMs) of polyethylene glycol (PEG)-casein and PEG-Tween20. Amphiphiles were added to maximize the percentage of enzyme remaining in fermented liquor that could be recycled twice back into the process. With no additive, in SHF the ethanol yield was declined by 64.0% and 80.0% after the first and second recycling, respectively. Application of PMs of PEG-casein in one cycle of SHF significantly improved the theoretical ethanol yield from 0.49 ± 0.00 to 0.91 ± 0.00 g/g compared to when only casein (0.66 ± 0.00 g/g), Tween 20 (0.53 ± 0.00 g/g) and Tween 20-PEG (0.77 ± 0.08 g/g) were used. PMs of PEG-Tween and PEG-casein also improved enzyme recycling, such that the ethanol yield was improved by 50% and 108% beyond that obtained with Tween and casein, respectively.
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Affiliation(s)
- Anahita Dehkhoda Eckard
- Department of Agricultural and Biosystems Engineering, 1400 North Campus Drive, South Dakota State University, Brookings, SD 57007, USA.
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17
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Wang ZJ, Lan TQ, Zhu JY. Lignosulfonate and elevated pH can enhance enzymatic saccharification of lignocelluloses. BIOTECHNOLOGY FOR BIOFUELS 2013; 6:9. [PMID: 24188090 PMCID: PMC3563490 DOI: 10.1186/1754-6834-6-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 09/13/2012] [Indexed: 05/02/2023]
Abstract
BACKGROUND Nonspecific (nonproductive) binding (adsorption) of cellulase by lignin has been identified as a key barrier to reduce cellulase loading for economical sugar and biofuel production from lignocellulosic biomass. Sulfite Pretreatment to Overcome Recalcitrance of Lignocelluloses (SPORL) is a relatively new process, but demonstrated robust performance for sugar and biofuel production from woody biomass especially softwoods in terms of yields and energy efficiencies. This study demonstrated the role of lignin sulfonation in enhancing enzymatic saccharification of lignocelluloses - lignosulfonate from SPORL can improve enzymatic hydrolysis of lignocelluloses, contrary to the conventional belief that lignin inhibits enzymatic hydrolysis due to nonspecific binding of cellulase. RESULTS The study found that lignosulfonate from SPORL pretreatment and from a commercial source inhibits enzymatic hydrolysis of pure cellulosic substrates at low concentrations due to nonspecific binding of cellulase. Surprisingly, the reduction in enzymatic saccharification efficiency of a lignocellulosic substrate was fully recovered as the concentrations of these two lignosulfonates increased. We hypothesize that lignosulfonate serves as a surfactant to enhance enzymatic hydrolysis at higher concentrations and that this enhancement offsets its inhibitive effect from nonspecific binding of cellulase, when lignosulfonate is applied to lignocellulosic solid substrates. Lignosulfonate can block nonspecific binding of cellulase by bound lignin on the solid substrates, in the same manner as a nonionic surfactant, to significantly enhance enzymatic saccharification. This enhancement is linearly proportional to the amount of lignosulfonate applied which is very important to practical applications. For a SPORL-pretreated lodgepole pine solid, 90% cellulose saccharification was achieved at cellulase loading of 13 FPU/g glucan with the application of its corresponding pretreatment hydrolysate coupled with increasing hydrolysis pH to above 5.5 compared with only 51% for the control run without lignosulfonate at pH 5.0. The pH-induced lignin surface modification at pH 5.5 further reduced nonspecific binding of cellulase by lignosulfonate. CONCLUSIONS The results reported in this study suggest significant advantages for SPORL-pretreatment in terms of reducing water usage and enzyme dosage, and simplifying process integration, i.e., it should eliminate washing of SPORL solid fraction for direct simultaneous enzymatic saccharification and combined fermentation of enzymatic and pretreatment hydrolysates (SSCombF). Elevated pH 5.5 or higher, rather than the commonly believed optimal and widely practiced pH 4.8-5.0, should be used in conducting enzymatic saccharification of lignocelluloses.
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Affiliation(s)
- ZJ Wang
- Key Lab of Paper Science & Technology, Shandong Polytechnic University, Jinan, China
- US Forest Service, Forest Products Laboratory, Madison, WI, USA
| | - TQ Lan
- US Forest Service, Forest Products Laboratory, Madison, WI, USA
- College of Light Industry and Food Sciences, South China University of Technology, Guangzhou, China
| | - JY Zhu
- US Forest Service, Forest Products Laboratory, Madison, WI, USA
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Li M, Tu M, Cao D, Bass P, Adhikari S. Distinct roles of residual xylan and lignin in limiting enzymatic hydrolysis of organosolv pretreated loblolly pine and sweetgum. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:646-54. [PMID: 23270516 DOI: 10.1021/jf304517w] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The interactions between xylan/lignin and cellulase enzymes play a key role in the effective hydrolysis of lignocellulosic biomass. Organosolv pretreated loblolly pine (OPLP) and sweetgum (OPSG) were used to quantitatively elucidate the distinct roles of residual xylan and lignin on enzymatic hydrolysis, based on the initial hydrolysis rates and the final hydrolysis yields. The initial hydrolysis rates of OPLP and OPSG were 1.45 (glucose) and 1.19 g/L/h (glucose), respectively, under the enzyme loading of 20 FPU/g glucan. The final glucan hydrolysis yields of OPLP and OPSG at 72 h were 76.4 and 98.9%, respectively. By correlating the amount of residual lignin and xylan to the initial hydrolysis rate and the final hydrolysis yield in OPLP and OPSG, a more accurate fundamental understanding of the roles of xylan and lignin in limiting the enzymatic hydrolysis has been developed. The higher amount of residual xylan (9.7%) in OPSG resulted in lower initial hydrolysis rate (1.19 g/L/h). The higher amount of residual lignin in OPLP (18.6%) resulted in lower final hydrolysis yield of glucan (76.4%). In addition, we observed in the simultaneous saccharification and fermentation (SSF) that ethyl xyloside was produced by the enzymatic catalysis of xylose/xylan and ethanol.
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Affiliation(s)
- Mi Li
- Forest Products Laboratory and Center for Bioenergy and Bioproducts, Auburn University, Auburn, Alabama 36849, United States
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19
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Analysis of casein biopolymers adsorption to lignocellulosic biomass as a potential cellulase stabilizer. J Biomed Biotechnol 2012; 2012:745181. [PMID: 23118515 PMCID: PMC3481958 DOI: 10.1155/2012/745181] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 07/03/2012] [Indexed: 11/17/2022] Open
Abstract
Although lignocellulosic materials have a good potential to substitute current feedstocks used for ethanol production, conversion of these materials to fermentable sugars is still not economical through enzymatic hydrolysis. High cost of cellulase has prompted research to explore techniques that can prevent from enzyme deactivation. Colloidal proteins of casein can form monolayers on hydrophobic surfaces that alleviate the de-activation of protein of interest. Scanning electron microscope (SEM), fourier transform infrared spectroscopy (FT-IR), capillary electrophoresis (CE), and Kjeldahl and BSA protein assays were used to investigate the unknown mechanism of action of induced cellulase activity during hydrolysis of casein-treated biomass. Adsorption of casein to biomass was observed with all of the analytical techniques used and varied depending on the pretreatment techniques of biomass. FT-IR analysis of amides I and II suggested that the substructure of protein from casein or skim milk were deformed at the time of contact with biomass. With no additive, the majority of one of the cellulase mono-component, 97.1 ± 1.1, was adsorbed to CS within 24 h, this adsorption was irreversible and increased by 2% after 72 h. However, biomass treatment with skim-milk and casein reduced the adsorption to 32.9% ± 6.0 and 82.8% ± 6.0, respectively.
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20
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Jeya M, Kalyani D, Dhiman SS, Kim H, Woo S, Kim D, Lee JK. Saccharification of woody biomass using glycoside hydrolases from Stereum hirsutum. BIORESOURCE TECHNOLOGY 2012; 117:310-316. [PMID: 22617039 DOI: 10.1016/j.biortech.2012.03.047] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 03/14/2012] [Accepted: 03/14/2012] [Indexed: 06/01/2023]
Abstract
Enzymatic saccharification of woody biomasses was performed using glycoside hydrolases from Stereum hirsutum, a newly isolated fungal strain found to secrete efficient glycoside hydrolases. The strain showed the highest β-glucosidase, cellobiohydrolase, endoglucanase, endoxylanase, laccase, and filter paper activity of 10.3, 1.7, 10.3, 29.9, 0.12, and 0.58 U/ml, respectively. Among the various biomasses tested for saccharification, pine biomass produced maximum reducing sugar. Response surface methodology was used to optimize the hydrolysis of pine biomass to achieve the highest level of sugars. The parameters including enzyme, substrate concentration, temperature and pH were found to be critical for the conversion of pine biomass into sugars. Maximum saccharification of 49.7% (435 mg/g-substrate) was obtained after 96 h of hydrolysis. A close agreement between the experimental results and the model predictions was achieved. S. hirsutum could be a good choice for the production of reducing sugars from cellulosic biomasses.
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Affiliation(s)
- Marimuthu Jeya
- Institute of SK-KU Biomaterials, Konkuk University, Seoul 143-701, Republic of Korea
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21
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Huang F, Ragauskas AJ. Dilute H2SO4 and SO2 pretreatments of Loblolly pine wood residue for bioethanol production. Ind Biotechnol (New Rochelle N Y) 2012. [DOI: 10.1089/ind.2011.0018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Fang Huang
- School of Chemistry and Biochemistry, Institute of Paper Science and Technology, Georgia Institute of Technology, Atlanta, GA
| | - Arthur J. Ragauskas
- School of Chemistry and Biochemistry, Institute of Paper Science and Technology, Georgia Institute of Technology, Atlanta, GA
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22
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Sipos B, Szilágyi M, Sebestyén Z, Perazzini R, Dienes D, Jakab E, Crestini C, Réczey K. Mechanism of the positive effect of poly(ethylene glycol) addition in enzymatic hydrolysis of steam pretreated lignocelluloses. C R Biol 2011; 334:812-23. [PMID: 22078738 DOI: 10.1016/j.crvi.2011.06.005] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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23
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Wei L, Shrestha A, Tu M, Adhikari S. Effects of surfactant on biochemical and hydrothermal conversion of softwood hemicellulose to ethanol and furan derivatives. Process Biochem 2011. [DOI: 10.1016/j.procbio.2011.06.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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24
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25
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Geddes CC, Nieves IU, Ingram LO. Advances in ethanol production. Curr Opin Biotechnol 2011; 22:312-9. [DOI: 10.1016/j.copbio.2011.04.012] [Citation(s) in RCA: 184] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Accepted: 04/18/2011] [Indexed: 12/23/2022]
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26
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Karki B, Maurer D, Jung S. Efficiency of pretreatments for optimal enzymatic saccharification of soybean fiber. BIORESOURCE TECHNOLOGY 2011; 102:6522-8. [PMID: 21470853 DOI: 10.1016/j.biortech.2011.03.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Revised: 03/05/2011] [Accepted: 03/05/2011] [Indexed: 05/30/2023]
Abstract
The effectiveness of several pretreatments [high-power ultrasound, sulfuric acid (H(2)SO(4)), sodium hydroxide (NaOH), and ammonium hydroxide (NH(3)OH)] to enhance glucose production from insoluble fractions recovered from enzyme-assisted aqueous extraction processing of extruded full-fat soybean flakes (FFSF) was investigated. Sonication of the insoluble fraction at 144 μm(pp (peak-to-peak)) for 30 and 60s did not improve the saccharification yield. The solid fractions recovered after pretreatment with H(2)SO(4) [1% (w/w), 90°C, 1.5h], NaOH [15% (w/w), 65°C, 17 h], and NH(3)OH [15% (w/w), 65°C, 17 h] showed significant lignin degradation, i.e., 81.9%, 71.2%, and 75.4%, respectively, when compared to the control (7.4%). NH(3)OH pretreatment resulted in the highest saccharification yield (63%) after 48 h of enzymatic saccharification. A treatment combining the extraction and saccharification steps and applied directly to the extruded FFSF, where oil extraction yield and saccharification yield reached 98% and 43%, respectively, was identified.
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Affiliation(s)
- Bishnu Karki
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011-1061, USA
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27
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The Effect of Gleditsia Saponin on Simultaneous Saccharification and Fermentation of Furfural Residue for Ethanol Production. ACTA ACUST UNITED AC 2011. [DOI: 10.4028/www.scientific.net/amr.236-238.108] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Simultaneous saccharification and fermentation is an attractive process configuration for bioethanol. However, the process cost in SSF is still high. Further reductions in cost are expected with reduction of enzyme addition and the use of waste agricultural or industrial materials as feedstock. Surfactant addition is a simple method to reduce the amount of enzyme loading. In the present work we explore the effect of Gleditsia Saponin, an inexpensive and natural surfactant, on SSF of furfural residue, a main waste of furfural industry in China, for ethanol production. Gleditsia Saponin addition even at low concentration, 0.04 g/l, increased the ethanol yield by 9.9%. Meanwhile, when Gleditsia Saponin addition was 0.16 g/l, the yield was increased by 22.8% and the enzyme activity significantly increased in the liquid fraction at the end of SSF, which would contribute to recover and recycle enzyme. Gleditsia Saponin addition at 1.25 g/l had a better performance in improving SSF efficiency than that of 2.5 g/l Tween-20 addition. The positive effects of Gleditsia Saponin addition on SSF, such as less enzyme loading and shorter residence time could also been observed.
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28
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Liu H, Zhu JY. Eliminating inhibition of enzymatic hydrolysis by lignosulfonate in unwashed sulfite-pretreated aspen using metal salts. BIORESOURCE TECHNOLOGY 2010; 101:9120-7. [PMID: 20674338 DOI: 10.1016/j.biortech.2010.07.035] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2010] [Revised: 07/07/2010] [Accepted: 07/10/2010] [Indexed: 05/08/2023]
Abstract
This study demonstrated the efficiency of Ca(II) and Mg(II) in removing inhibition of enzymatic hydrolysis by lignosulfonate through non-productive adsorption of enzymes. Adding 1 mmol/g cellulose of either metal salt restores approximately 65% of the activity lost when a pure cellulose/cellulase solution is spiked with lignosulfonate. Addition of either Ca(II) or Mg(II) is also effective in counteracting soluble inhibitors of cellulase present in unwashed aspen solid substrate produced by SPORL (sulfite pretreatment to overcome recalcitrance of lignocelluloses). Soluble inhibitors are often removed by thoroughly washing the lignocellulosic solid substrate following pretreatment. It was determined that adding 1 mmol of MgSO(4)/g substrate (oven dry) to the unwashed aspen substrate gave enzymatic substrate digestibility (SED) equivalent to that of washing for a range of enzyme loadings. These results demonstrate that applying divalent metal salts eliminates the need for washing, thereby saving considerable process water and cost for production of chemicals and biofuels from lignocellulose.
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Affiliation(s)
- Hao Liu
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China
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29
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Liu H, Zhu JY, Fu SY. Effects of lignin-metal complexation on enzymatic hydrolysis of cellulose. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:7233-8. [PMID: 20509690 DOI: 10.1021/jf1001588] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
This study investigated the inhibition of enzymatic hydrolysis by unbound lignin (soluble and insoluble) with or without the addition of metal compounds. Sulfonated, Organosolv, and Kraft lignin were added in aqueous enzyme-cellulose systems at different concentrations before hydrolysis. The measured substrate enzymatic digestibility (SED) of cellulose was decreased by 15% when SL was added to a concentration of 0.1 g/L due to nonproductive adsorption of enzymes onto lignin. Cu(II) and Fe(III) were found to inhibit enzymatic cellulose hydrolysis in the presence of lignin. Ca(II) and Mg(II) were found to reduce or eliminate nonproductive enzyme adsorption by the formation of lignin-metal complex. The addition of Ca(II) or Mg(II) to a concentration of 10 mM can almost completely eliminate the reduction in SED caused by the nonproductive enzyme adsorption onto the lignins studied (SL, OL, or KL at concentration of 0.1 g/L). Ca(II) was also found to reduce the inhibitive effect of bound lignin in pretreated wood substrate, suggesting that Ca(II) can also form complex with bound lignin on pretreated solid lignocelluloses. Significant improvement in SED of about over 27% of a eucalyptus substrate produced by sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) was achieved with the application of Ca(II).
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Affiliation(s)
- H Liu
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China
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30
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Zhu JY, Pan X, Zalesny RS. Pretreatment of woody biomass for biofuel production: energy efficiency, technologies, and recalcitrance. Appl Microbiol Biotechnol 2010; 87:847-57. [PMID: 20473606 DOI: 10.1007/s00253-010-2654-8] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 04/27/2010] [Accepted: 04/27/2010] [Indexed: 10/19/2022]
Abstract
This mini review discusses several key technical issues associated with cellulosic ethanol production from woody biomass: energy consumption for woody biomass pretreatment, pretreatment energy efficiency, woody biomass pretreatment technologies, and quantification of woody biomass recalcitrance. Both total sugar yield and pretreatment energy efficiency, defined as the total sugar recovery divided by total energy consumption for pretreatment, should be used to evaluate the performance of a pretreatment process. A post-chemical pretreatment wood size-reduction approach was proposed to significantly reduce energy consumption. The review also emphasizes using a low liquid-to-wood ratio (L/W) to reduce thermal energy consumption for any thermochemical/physical pretreatment in addition to reducing pretreatment temperature.
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Affiliation(s)
- J Y Zhu
- USDA Forest Service, Forest Products Laboratory, One Gifford Pinchot Drive, Madison, WI 53726-2398, USA.
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