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Li X, Chen J, Liu Y, Fu S, Zhang P, Zhang N, Li W, Zhang H. Traditional Chinese medicine residue enzymatic hydrolysates for production of polyhydroxyalkanoate by newly isolated Bacillus altitudinis. BIORESOURCE TECHNOLOGY 2024; 394:130277. [PMID: 38176596 DOI: 10.1016/j.biortech.2023.130277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 12/28/2023] [Accepted: 12/28/2023] [Indexed: 01/06/2024]
Abstract
Traditional Chinese medicine residue (TCMR) was utilized as an inexpensive carbon source for the production of poly(3-hydroxybutyrate) (PHB) using the newly isolated Bacillus altitudinis HBU-SI7. The results showed that Yu Ping Feng TCMR could be directly hydrolysed by cellulase to obtain a high proportion of glucose (99 % of total sugar) without pretreatment, achieving an enzymatic hydrolysis rate of up to 89.2 %. B. altitudinis could grow and produce PHB when using enzymatically hydrolysed TCMR in a 5-L fermenter. After 20 h of fermentation, the maximum concentration of PHB was 11.2 g/L, and the highest cell dry weight (CDW) was 15.4 g/L, with 72.7 % of the PHB fraction in CDW. Moreover, this strain could utilize enzymatic hydrolysates from various herbal formulas to produce high levels of PHB. This novel approach aims to accumulate PHB from TCMR hydrolysates, offering an effective and environmentally friendly method to reduce production costs and achieve mass production.
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Affiliation(s)
- Xinyue Li
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Jing Chen
- Baoding Jizhong Pharmaceutical Co. Ltd. Hebei Baoding 071000, China
| | - Yahui Liu
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Shuangqing Fu
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China
| | - Peixun Zhang
- Baoding Jizhong Pharmaceutical Co. Ltd. Hebei Baoding 071000, China
| | - Na Zhang
- Baoding Jizhong Pharmaceutical Co. Ltd. Hebei Baoding 071000, China
| | - Wei Li
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China.
| | - Honglei Zhang
- College of Chemistry and Materials Science, Key Laboratory of Chemical Biology of Hebei Province, Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Institute of Life Science and Green Development, Hebei University, Baoding 071002, China.
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Mierke F, Brink DP, Norbeck J, Siewers V, Andlid T. Functional genome annotation and transcriptome analysis of Pseudozyma hubeiensis BOT-O, an oleaginous yeast that utilizes glucose and xylose at equal rates. Fungal Genet Biol 2023; 166:103783. [PMID: 36870442 DOI: 10.1016/j.fgb.2023.103783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 02/10/2023] [Accepted: 02/27/2023] [Indexed: 03/06/2023]
Abstract
Pseudozyma hubeiensis is a basidiomycete yeast that has the highly desirable traits for lignocellulose valorisation of being equally efficient at utilization of glucose and xylose, and capable of their co-utilization. The species has previously mainly been studied for its capacity to produce secreted biosurfactants in the form of mannosylerythritol lipids, but it is also an oleaginous species capable of accumulating high levels of triacylglycerol storage lipids during nutrient starvation. In this study, we aimed to further characterize the oleaginous nature of P. hubeiensis by evaluating metabolism and gene expression responses during storage lipid formation conditions with glucose or xylose as a carbon source. The genome of the recently isolated P. hubeiensis BOT-O strain was sequenced using MinION long-read sequencing and resulted in the most contiguous P. hubeiensis assembly to date with 18.95 Mb in 31 contigs. Using transcriptome data as experimental support, we generated the first mRNA-supported P. hubeiensis genome annotation and identified 6540 genes. 80% of the predicted genes were assigned functional annotations based on protein homology to other yeasts. Based on the annotation, key metabolic pathways in BOT-O were reconstructed, including pathways for storage lipids, mannosylerythritol lipids and xylose assimilation. BOT-O was confirmed to consume glucose and xylose at equal rates, but during mixed glucose-xylose cultivation glucose was found to be taken up faster. Differential expression analysis revealed that only a total of 122 genes were significantly differentially expressed at a cut-off of |log2 fold change| ≥ 2 when comparing cultivation on xylose with glucose, during exponential growth and during nitrogen-starvation. Of these 122 genes, a core-set of 24 genes was identified that were differentially expressed at all time points. Nitrogen-starvation resulted in a larger transcriptional effect, with a total of 1179 genes with significant expression changes at the designated fold change cut-off compared with exponential growth on either glucose or xylose.
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Affiliation(s)
- Friederike Mierke
- Food and Nutrition Science, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden; Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Daniel P Brink
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden; Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | - Joakim Norbeck
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Verena Siewers
- Systems and Synthetic Biology, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden.
| | - Thomas Andlid
- Food and Nutrition Science, Department of Life Sciences, Chalmers University of Technology, Gothenburg, Sweden
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Silva VTF, Ruschoni UCM, Ferraz A, Milagres AMF. Xylan, Xylooligosaccharides, and Aromatic Structures With Antioxidant Activity Released by Xylanase Treatment of Alkaline-Sulfite–Pretreated Sugarcane Bagasse. Front Bioeng Biotechnol 2022; 10:940712. [PMID: 35898646 PMCID: PMC9313595 DOI: 10.3389/fbioe.2022.940712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 06/09/2022] [Indexed: 11/29/2022] Open
Abstract
Xylanase enzymes are useful to fractionate plant biomass, producing xylan, xylooligosaccharides (XOS), and antioxidant-derived XOS. In a biorefinery, pretreated biomass can be digested with xylanase prior to cellulose saccharification, enhancing the product portfolio in the process. With this vision, this study highlighted a wide range of new products attainable from alkaline-sulfite–pretreated sugarcane bagasse by treatments with endo-xylanase under controlled conditions. The developed process provided a crude extract corresponding to 29.7% (w/w) of pretreated sugarcane bagasse. The crude extract included a relatively polymeric glucuronoarabinoxylan fraction, DP2-DP6 xylooligosaccharides, and aromatic compounds. The enzymatically produced extract was fractionated with increasing ethanol concentrations [up to 90% (v/v)], providing precipitation of varied polymeric xylan fractions (48% (w/w) of the crude extract) with average molar masses ranging from 28 kDa to 3.6 kDa. The fraction soluble in 90% ethanol was subjected to adsorption on 4% (w/v) activated charcoal and eluted with an ethanol gradient from 10% to 70% (v/v), thus providing xylooligosaccharides and aromatic fractions. Most of the xylooligosaccharides (74% of the eluted sugars) were washed out in 10%–30% ethanol. DP2 and DP3 structures predominated in the 10% ethanol fraction, while DP5 structures were significantly enriched in the 30% ethanol fraction. Higher ethanol concentrations desorbed xylooligosaccharides associated with higher amounts of aromatic compounds. Total aromatics, phenolic structures, and p-hydroxycinnamates predominated in the fractions desorbed with 60% and 70% ethanol. The antioxidant activity of produced fractions correlated with their phenolic contents. Compiled results indicate that a wide variety of products can be prepared from pretreated biomass using xylanase-aided extraction procedures. Recovered fractions presented different features and specific application prospects. Beyond polymeric xylan with low lignin contamination, xylooligosaccharides or even lignin-carbohydrate complexes with antioxidant activity can be included in the biorefinery portfolio based on the currently developed fractionation studies.
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Karnitski A, Choi JW, Suh DJ, Yoo CJ, Lee H, Kim KH, Kim CS, Kim K, Ha JM. Roles of metal and acid sites in the reductive depolymerization of concentrated lignin over supported Pd catalysts. Catal Today 2022. [DOI: 10.1016/j.cattod.2022.07.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Chen X, He D, Hou T, Lu M, Mosier NS, Han L, Xiao W. Structure-property-degradability relationships of varisized lignocellulosic biomass induced by ball milling on enzymatic hydrolysis and alcoholysis. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:36. [PMID: 35379297 PMCID: PMC8981931 DOI: 10.1186/s13068-022-02133-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 03/22/2022] [Indexed: 11/29/2022]
Abstract
Background Valorization of lignocellulosic biomass to obtain clean fuels and high-value chemicals is attractive and essential for sustainable energy and chemical production, but the complex structure of biomass is recalcitrant to catalytic processing. This recalcitrance can be overcome by pretreating biomass into deconstructable components, which involves altering the structural complexities and physicochemical properties. However, the impact of these alterations on biomass deconstruction varies considerably, depending on the pretreatment and subsequent conversion type. Here, we systematically describe the changes in structure and properties of corn stover after ball milling as well as their influence on the following enzymatic saccharification and acid-catalyzed alcoholysis, with the aim of elucidating the relationships between structures, properties and deconstructable potential of lignocellulosic biomass. Results Ball milling causes dramatic structural changes, since the resistant plant cell walls are destroyed with size reduction to a cellular scale, leading to the increase in surface area and reducing ends, and decrease in crystallinity and thermal stability. As a result, ball-milled corn stover is more susceptible to enzymatic saccharification to fermentable sugars and provides more industrially viable processing approaches, as it is effective at high solids loading and minor enzyme loading, without any other pretreatment. Acid-catalyzed alcoholysis of corn stover to biofuels, on the other hand, is also enhanced by ball milling, but additional processing parameters should be tailored to the needs of efficient conversion. Further, a detailed examination of process variables coupled with a kinetic study indicates that acid-catalyzed alcoholysis is limited by the process variables rather than by the substrate parameters, whereas ball milling facilitates this reaction to some extent, especially under mild conditions, by lowering the activation energy of corn stover decomposition. Conclusions The efficient catalytic conversion of biomass is closely related to its structure and properties, an understanding of which offers prospects for the rational improvement of methods aimed at more economic commercial biorefineries. Supplementary Information The online version contains supplementary material available at 10.1186/s13068-022-02133-x.
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Affiliation(s)
- Xueli Chen
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Haidian district, P.O. Box 191, Beijing, 100083, China.,Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN, 47907, USA.,Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Dingping He
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Haidian district, P.O. Box 191, Beijing, 100083, China
| | - Tao Hou
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Haidian district, P.O. Box 191, Beijing, 100083, China
| | - Minsheng Lu
- School of Light Industry and Food Engineering, Guangxi Key Laboratory of Clean Pulp and Papermaking and Pollution Control, Guangxi University, Nanning, 530004, China
| | - Nathan S Mosier
- Laboratory of Renewable Resources Engineering (LORRE), Purdue University, West Lafayette, IN, 47907, USA.,Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Lujia Han
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Haidian district, P.O. Box 191, Beijing, 100083, China
| | - Weihua Xiao
- Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University (East Campus), 17 Qing-Hua-Dong-Lu, Haidian district, P.O. Box 191, Beijing, 100083, China.
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Chen P, Dai K, Wang Z, Zhuang W, Yang P, Ying H, Wu J. Separation and recovery of alkali lignin and NaOH based on size exclusion methodology. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.117852] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Hailu AM, Asfaw SL, Tegaye TA. Effect of carbon-rich-waste addition as co-substrate on the performance and stability of anaerobic digestion of abattoir wastewater without agitation. BIORESOUR BIOPROCESS 2020. [DOI: 10.1186/s40643-020-00333-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractMultiple wastes’ co-digestion is one of the alternatives for improved anaerobic digestion (AD) process of industrial and municipal wastes. The present work investigated the influence of fruit–vegetable solid waste (FVW) addition as a co-substrate on the performance of AD of abattoir wastewater (AWW). The co-digestion was done at a lab-scale-based experiment under mesophilic condition using a two-phase anaerobic sequencing batch reactor without agitation. It was tested at different mixing ratios (100%AWW; 75%AWW:25%FVW; 50%AWW:50%FVW; 25%AWW:75%FVW; 100%FVW) with the intention of looking for the best mixing ratio with the best performance. It was fed on a semi-continuous basis and operated for 18 days (d) total retention time (HRT): 3 days for the acidogenesis reactor and 15 days for methanogenesis reactor. The addition of FVW enhanced biogas yield and VS removal by 70.26% and 57.11%, respectively, at optimum mixing ratio. Moreover, to some extent improvement of AD process stability verified by the decreased TVFA:TAlk ratio and free ammonia nitrogen was observed upon progressive addition of FVW. Finally, this co-digestion process should further be studied for its performance at different HRTs with agitation.
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Althuri A, Venkata Mohan S. Sequential and consolidated bioprocessing of biogenic municipal solid waste: A strategic pairing of thermophilic anaerobe and mesophilic microaerobe for ethanol production. BIORESOURCE TECHNOLOGY 2020; 308:123260. [PMID: 32251860 DOI: 10.1016/j.biortech.2020.123260] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 03/23/2020] [Accepted: 03/24/2020] [Indexed: 06/11/2023]
Abstract
Feedstock availability and its pretreatment, high process economics and insufficient ethanol (HEt) titres necessitated the bioprocesses that are sustainable. The advanced consolidated bioprocessing (CBPSeq) strategy presently considered for improved HEt production involves, sequential coupling of CBP thermophile, Clostridium thermocellum ATCC-27405 with mesophilic microaerobe, Pichia stipitis NCIM-3498. Biogenic municipal solid waste (BMSW) pretreated with 0.5% NaOH (CSPBMSW) served as the sole carbon source. CBPSeq (23.99 g/L) fared better than CBP standalone (18.10 g/L) wherein 1.32-folds improvement in HEt titre was recorded. Considering insufficient xylanase titre in cellulosome complex of C. thermocellum, CBPSeq was performed employing exogenous xylanases (CBPSeqE) to improve xylan digestibility and HEt yield. CBPSeqE-II biosystem at pH 5 showed maximum HEt titre of 36.90 g/L which corresponds to yield of 0.26 g HEt/ g CSPBMSW. This study substantiates efficacy of CBPSeqE-II biosystem in sustainable bioethanol production from BMSW in a single reactor without laborious steps.
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Affiliation(s)
- Avanthi Althuri
- Bioengineering and Environmental Sciences Lab, Energy and Environmental Engineering, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500007, Telangana, India.
| | - S Venkata Mohan
- Bioengineering and Environmental Sciences Lab, Energy and Environmental Engineering, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500007, Telangana, India
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10
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Quantifying reductions in soaking in aqueous ammonia pretreatment severity and enzymatic hydrolysis conditions for corn stover pellets. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biteb.2019.100187] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Althuri A, Venkata Mohan S. Single pot bioprocessing for ethanol production from biogenic municipal solid waste. BIORESOURCE TECHNOLOGY 2019; 283:159-167. [PMID: 30903822 DOI: 10.1016/j.biortech.2019.03.055] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 03/07/2019] [Accepted: 03/09/2019] [Indexed: 06/09/2023]
Abstract
Burgeoning global energy demand and rapid diminution of fossil fuel reserves urged to seek for a sustainable energy source like bioethanol. Single pot bioprocessing (SPB) strategy employing in-house laccase, cellulase plus xylanase and amylase along with hexose and pentose sugar fermenting yeasts (Saccharomyces cerevisiae and Pichia stipitis) is designed in this study for ethanol production from biogenic municipal solid waste (BMSW). BMSW when subjected to simultaneous pretreatment and saccharification (SPS) resulted in 79.69% enzymatic digestibility and fared better compared to alkali pretreated counterparts (14.03%-51.10%). The maximum total sugar release in case of SPS was 146.9 g/L in 24 h. The maximum ethanol concentration of 5.24% (v/v) in 30 h was obtained from SPB of BMSW at 25% (w/v) solid loading. SPB for ethanol production from BMSW is an interesting and effective alternative to MSW going to landfill or incineration with an added perk of waste to wealth conversion.
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Affiliation(s)
- Avanthi Althuri
- Bioengineering and Environmental Sciences Lab, CEEFF, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500007, Telangana, India
| | - S Venkata Mohan
- Bioengineering and Environmental Sciences Lab, CEEFF, CSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500007, Telangana, India.
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Assaying Sorghum for Fuel Production. Methods Mol Biol 2019. [PMID: 30652296 DOI: 10.1007/978-1-4939-9039-9_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The publicly available NREL suite of laboratory analytical procedures (LAPs) provides researchers with the analytical tools to determine the composition of woody and herbaceous feedstocks. Feedstock characterization includes several steps: sample preparation, starch determination, moisture analysis, ashing, extraction, and hydrolysis. These steps provide information on specific compounds and classes of compounds such as ash, protein, moisture, extractives, sucrose, starch, glucan, xylan, galactan, arabinan, acetate and lignin. Here, we describe the use of these procedures to characterize sorghum [Sorghum bicolor (L.) Moench] with specific consideration of four main sorghum types: grain, forage, sweet, and biomass, which can vary significantly in composition. Special attention is paid to the extraction and the differentiation of glucose from starch and glucan from cellulose in the hybrids with significant amounts of nonstructural carbohydrates.
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Ona JI, Halling PJ, Ballesteros M. Enzyme hydrolysis of cassava peels: treatment by amylolytic and cellulolytic enzymes. BIOCATAL BIOTRANSFOR 2019. [DOI: 10.1080/10242422.2018.1551376] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- John Ikuba Ona
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK
- Department of Chemistry, University of Agriculture, Makurdi, Nigeria
| | - Peter J. Halling
- WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow, UK
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Son D, Gu S, Choi JW, Suh DJ, Jae J, Choi J, Ha JM. Production of phenolic hydrocarbons from organosolv lignin and lignocellulose feedstocks of hardwood, softwood, grass and agricultural waste. J IND ENG CHEM 2019. [DOI: 10.1016/j.jiec.2018.09.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Dos Santos AC, Ximenes E, Kim Y, Ladisch MR. Lignin-Enzyme Interactions in the Hydrolysis of Lignocellulosic Biomass. Trends Biotechnol 2018; 37:518-531. [PMID: 30477739 DOI: 10.1016/j.tibtech.2018.10.010] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/22/2018] [Accepted: 10/25/2018] [Indexed: 12/20/2022]
Abstract
Lignin is central to overcoming recalcitrance in the enzyme hydrolysis of lignocellulose. While the term implies a physical barrier in the cell wall structure, there are also important biochemical components that direct interactions between lignin and the hydrolytic enzymes that attack cellulose in plant cell walls. Progress toward a deeper understanding of the lignin synthesis pathway - and the consistency between a range of observations over the past 40 years in the very extensive literature on cellulose hydrolysis - is resulting in advances in reducing a major impediment to cellulose conversion: the cost of enzymes. This review addresses lignin and its role in the hydrolysis of hardwood and other lignocellulosic residues.
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Affiliation(s)
- Antonio Carlos Dos Santos
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907, USA; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Eduardo Ximenes
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907, USA; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Youngmi Kim
- Department of Agricultural Engineering Technology, University of Wisconsin, River Falls, WI 54022, USA
| | - Michael R Ladisch
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, IN 47907, USA; Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, USA; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA; www.purdue.edu/LORRE.
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Choong FX, Bäck M, Schulz A, Nilsson KPR, Edlund U, Richter-Dahlfors A. Stereochemical identification of glucans by oligothiophenes enables cellulose anatomical mapping in plant tissues. Sci Rep 2018; 8:3108. [PMID: 29449697 PMCID: PMC5814555 DOI: 10.1038/s41598-018-21466-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 02/01/2018] [Indexed: 02/03/2023] Open
Abstract
Efficient use of plant-derived materials requires enabling technologies for non-disruptive composition analysis. The ability to identify and spatially locate polysaccharides in native plant tissues is difficult but essential. Here, we develop an optical method for cellulose identification using the structure-responsive, heptameric oligothiophene h-FTAA as molecular fluorophore. Spectrophotometric analysis of h-FTAA interacting with closely related glucans revealed an exceptional specificity for β-linked glucans. This optical, non-disruptive method for stereochemical differentiation of glycosidic linkages was next used for in situ composition analysis in plants. Multi-laser/multi-detector analysis developed herein revealed spatial localization of cellulose and structural cell wall features such as plasmodesmata and perforated sieve plates of the phloem. Simultaneous imaging of intrinsically fluorescent components revealed the spatial relationship between cell walls and other organelles, such as chloroplasts and lignified annular thickenings of the trachea, with precision at the sub-cellular scale. Our non-destructive method for cellulose identification lays the foundation for the emergence of anatomical maps of the chemical constituents in plant tissues. This rapid and versatile method will likely benefit the plant science research fields and may serve the biorefinery industry as reporter for feedstock optimization as well as in-line monitoring of cellulose reactions during standard operations.
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Affiliation(s)
- Ferdinand X Choong
- Swedish Medical Nanoscience Center, Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Marcus Bäck
- Department of Chemistry, IFM, Linköping University, Linköping, SE-581 83, Sweden
| | - Anette Schulz
- Swedish Medical Nanoscience Center, Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - K Peter R Nilsson
- Department of Chemistry, IFM, Linköping University, Linköping, SE-581 83, Sweden
| | - Ulrica Edlund
- Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Agneta Richter-Dahlfors
- Swedish Medical Nanoscience Center, Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77, Sweden.
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Physico-Chemical Conversion of Lignocellulose: Inhibitor Effects and Detoxification Strategies: A Mini Review. Molecules 2018; 23:molecules23020309. [PMID: 29389875 PMCID: PMC6017906 DOI: 10.3390/molecules23020309] [Citation(s) in RCA: 157] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 01/18/2018] [Accepted: 01/30/2018] [Indexed: 11/20/2022] Open
Abstract
A pretreatment of lignocellulosic biomass to produce biofuels, polymers, and other chemicals plays a vital role in the biochemical conversion process toward disrupting the closely associated structures of the cellulose-hemicellulose-lignin molecules. Various pretreatment steps alter the chemical/physical structure of lignocellulosic materials by solubilizing hemicellulose and/or lignin, decreasing the particle sizes of substrate and the crystalline portions of cellulose, and increasing the surface area of biomass. These modifications enhance the hydrolysis of cellulose by increasing accessibilities of acids or enzymes onto the surface of cellulose. However, lignocellulose-derived byproducts, which can inhibit and/or deactivate enzyme and microbial biocatalysts, are formed, including furan derivatives, lignin-derived phenolics, and carboxylic acids. These generation of compounds during pretreatment with inhibitory effects can lead to negative effects on subsequent steps in sugar flat-form processes. A number of physico-chemical pretreatment methods such as steam explosion, ammonia fiber explosion (AFEX), and liquid hot water (LHW) have been suggested and developed for minimizing formation of inhibitory compounds and alleviating their effects on ethanol production processes. This work reviews the physico-chemical pretreatment methods used for various biomass sources, formation of lignocellulose-derived inhibitors, and their contributions to enzymatic hydrolysis and microbial activities. Furthermore, we provide an overview of the current strategies to alleviate inhibitory compounds present in the hydrolysates or slurries.
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Althuri A, Gujjala LKS, Banerjee R. Partially consolidated bioprocessing of mixed lignocellulosic feedstocks for ethanol production. BIORESOURCE TECHNOLOGY 2017; 245:530-539. [PMID: 28898853 DOI: 10.1016/j.biortech.2017.08.140] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 08/21/2017] [Accepted: 08/22/2017] [Indexed: 06/07/2023]
Abstract
Rapid urbanization and industrialization have accelerated the energy demand which cannot be met by decreasing fossil fuels thereby substantiate the need for lignocellulosic ethanol. The present study is one such attempt towards bioethanol production in an eco-friendly manner using enzymes in which a mixture of lignocellulosic biomass namely, Ricinus communis, Saccharum officinarum (tops) and Saccharum spontaneum were taken as a substrate. The mixed biomass was processed through partially consolidated bioprocessing (PCBP) approach which involves a non-isothermal simultaneous pretreatment and saccharification step where a concoction of laccase (Pleurotus djamor) and holocellulase (Trichoderma reseei RUT C30) was used followed by co-fermentation within the same reactor. The process parameters influencing PCBP were optimized using feed-forward ANN model which resulted in a maximum ethanol concentration of 7.86% (v/v) (62.01g/L) at pentose to hexose strain ratio of 0.696 (v/v), substrate loading of 27.54% (w/v) and incubation time of 21.96h.
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Affiliation(s)
- Avanthi Althuri
- Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur 721 302, India
| | | | - Rintu Banerjee
- Agricultural & Food Engineering Department, Indian Institute of Technology, Kharagpur 721 302, India; Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur 721 302, India.
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19
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Das L, Liu E, Saeed A, Williams DW, Hu H, Li C, Ray AE, Shi J. Industrial hemp as a potential bioenergy crop in comparison with kenaf, switchgrass and biomass sorghum. BIORESOURCE TECHNOLOGY 2017; 244:641-649. [PMID: 28810219 DOI: 10.1016/j.biortech.2017.08.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 08/02/2017] [Accepted: 08/03/2017] [Indexed: 05/17/2023]
Abstract
This study takes combined field trial, lab experiment, and economic analysis approaches to evaluate the potential of industrial hemp in comparison with kenaf, switchgrass and biomass sorghum. Agronomy data suggest that the per hectare yield (5437kg) of industrial hemp stem alone was at a similar level with switchgrass and sorghum; while the hemp plants require reduced inputs. Field trial also showed that ∼1230kg/ha hemp grain can be harvested in addition to stems. Results show a predicted ethanol yield of ∼82gallons/dry ton hemp stems, which is comparable to the other three tested feedstocks. A comparative cost analysis indicates that industrial hemp could generate higher per hectare gross profit than the other crops if both hemp grains and biofuels from hemp stem were counted. These combined evaluation results demonstrate that industrial hemp has great potential to become a promising regional commodity crop for producing both biofuels and value-added products.
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Affiliation(s)
- Lalitendu Das
- Biosystems and Agricultural Engineering Department, University of Kentucky, Lexington, KY 40546, United States
| | - Enshi Liu
- Biosystems and Agricultural Engineering Department, University of Kentucky, Lexington, KY 40546, United States
| | - Areej Saeed
- Biosystems and Agricultural Engineering Department, University of Kentucky, Lexington, KY 40546, United States
| | - David W Williams
- Plant and Soils Science Department, University of Kentucky, Lexington, KY 40546, United States; Robinson Center for Appalachian Resource Sustainability (RCARS), Jackson, KY 41339, United States
| | - Hongqiang Hu
- Energy and Environment Science and Technology, Idaho National Laboratory, Idaho Falls, ID 83415, United States
| | - Chenlin Li
- Energy and Environment Science and Technology, Idaho National Laboratory, Idaho Falls, ID 83415, United States
| | - Allison E Ray
- Energy and Environment Science and Technology, Idaho National Laboratory, Idaho Falls, ID 83415, United States
| | - Jian Shi
- Biosystems and Agricultural Engineering Department, University of Kentucky, Lexington, KY 40546, United States.
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20
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Verma SK, Fenila F, Shastri Y. Sensitivity analysis and stochastic modelling of lignocellulosic feedstock pretreatment and hydrolysis. Comput Chem Eng 2017. [DOI: 10.1016/j.compchemeng.2017.05.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Krasznai DJ, Champagne Hartley R, Roy HM, Champagne P, Cunningham MF. Compositional analysis of lignocellulosic biomass: conventional methodologies and future outlook. Crit Rev Biotechnol 2017; 38:199-217. [PMID: 28595468 DOI: 10.1080/07388551.2017.1331336] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The composition and structural properties of lignocellulosic biomass have significant effects on its downstream conversion to fuels, biomaterials, and building-block chemicals. Specifically, the recalcitrance to modification and compositional variability of lignocellulose make it challenging to optimize and control the conditions under which the conversion takes place. Various characterization protocols have been developed over the past 150 years to elucidate the structural properties and compositional patterns that affect the processing of lignocellulose. Early characterization techniques were developed to estimate the relative digestibility and nutritional value of plant material after ingestion by ruminants and humans alike (e.g. dietary fiber). Over the years, these empirical techniques have evolved into statistical approaches that give a broader and more informative analysis of lignocellulose for conversion processes, to the point where an entire compositional and structural analysis of lignocellulosic biomass can be completed in minutes, rather than weeks. The use of modern spectroscopy and chemometric techniques has shown promise as a rapid and cost effective alternative to traditional empirical techniques. This review serves as an overview of the compositional analysis techniques that have been developed for lignocellulosic biomass in an effort to highlight the motivation and migration towards rapid, accurate, and cost-effective data-driven chemometric methods. These rapid analysis techniques can potentially be used to optimize future biorefinery unit operations, where large quantities of lignocellulose are continually processed into products of high value.
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Affiliation(s)
- Daniel J Krasznai
- a Department of Chemical Engineering , Queen's University , Kingston , Ontario , Canada
| | | | - Hannah M Roy
- b Department of Civil Engineering & Department of Chemical Engineering , Queen's University , Kingston , Ontario , Canada
| | - Pascale Champagne
- a Department of Chemical Engineering , Queen's University , Kingston , Ontario , Canada
| | - Michael F Cunningham
- a Department of Chemical Engineering , Queen's University , Kingston , Ontario , Canada
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22
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Zafra G, Absalón ÁE, Anducho-Reyes MÁ, Fernandez FJ, Cortés-Espinosa DV. Construction of PAH-degrading mixed microbial consortia by induced selection in soil. CHEMOSPHERE 2017; 172:120-126. [PMID: 28063314 DOI: 10.1016/j.chemosphere.2016.12.038] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 12/06/2016] [Accepted: 12/08/2016] [Indexed: 05/22/2023]
Abstract
Bioremediation of polycyclic aromatic hydrocarbons (PAHs)-contaminated soils through the biostimulation and bioaugmentation processes can be a strategy for the clean-up of oil spills and environmental accidents. In this work, an induced microbial selection method using PAH-polluted soils was successfully used to construct two microbial consortia exhibiting high degradation levels of low and high molecular weight PAHs. Six fungal and seven bacterial native strains were used to construct mixed consortia with the ability to tolerate high amounts of phenanthrene (Phe), pyrene (Pyr) and benzo(a)pyrene (BaP) and utilize these compounds as a sole carbon source. In addition, we used two engineered PAH-degrading fungal strains producing heterologous ligninolytic enzymes. After a previous selection using microbial antagonism tests, the selection was performed in microcosm systems and monitored using PCR-DGGE, CO2 evolution and PAH quantitation. The resulting consortia (i.e., C1 and C2) were able to degrade up to 92% of Phe, 64% of Pyr and 65% of BaP out of 1000 mg kg-1 of a mixture of Phe, Pyr and BaP (1:1:1) after a two-week incubation. The results indicate that constructed microbial consortia have high potential for soil bioremediation by bioaugmentation and biostimulation and may be effective for the treatment of sites polluted with PAHs due to their elevated tolerance to aromatic compounds, their capacity to utilize them as energy source.
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Affiliation(s)
- German Zafra
- Instituto Politécnico Nacional, Centro de Investigación en Biotecnología Aplicada, Carretera Estatal San Inés Tecuexcomac-Tepetitla Km 1.5, C.P. 90700, Tepetitla de Lardizabal, Tlaxcala, Mexico
| | - Ángel E Absalón
- Instituto Politécnico Nacional, Centro de Investigación en Biotecnología Aplicada, Carretera Estatal San Inés Tecuexcomac-Tepetitla Km 1.5, C.P. 90700, Tepetitla de Lardizabal, Tlaxcala, Mexico
| | - Miguel Ángel Anducho-Reyes
- Universidad Politécnica de Pachuca, Laboratorio de Microbiología Molecular, Carretera Pachuca-Cd, Sahagún, Km 20, Ex-Hacienda de Santa Bárbara, Zempoala, Hidalgo, Mexico
| | - Francisco J Fernandez
- Departamento de Biotecnología, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Vicentina, C.P. 09340, México, D.F., Mexico
| | - Diana V Cortés-Espinosa
- Instituto Politécnico Nacional, Centro de Investigación en Biotecnología Aplicada, Carretera Estatal San Inés Tecuexcomac-Tepetitla Km 1.5, C.P. 90700, Tepetitla de Lardizabal, Tlaxcala, Mexico.
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23
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Galkin M, Di Francesco D, Edlund U, Samec JSM. Sustainable sources need reliable standards. Faraday Discuss 2017; 202:281-301. [DOI: 10.1039/c7fd00046d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review discusses the challenges within the research area of modern biomass fractionation and valorization. The current pulping industry focuses on pulp production and the resulting cellulose fiber. Hemicellulose and lignin are handled as low value streams for process heat and the regeneration of process chemicals. The paper and pulp industry have therefore developed analytical techniques to evaluate the cellulose fiber, while the other fractions are given a low priority. In a strive to also use the hemicellulose and lignin fractions of lignocellulosic biomass, moving towards a biorefining concept, there are severe shortcomings with the current pulping techniques and also in the analysis of the biomass. Lately, new fractionation techniques have emerged which valorize a larger extent of the lignocellulosic biomass. This progress has disclosed the shortcomings in the analysis of mainly the hemicellulose and lignin structure and properties. To move the research field forward, analytical tools for both the raw material, targeting all the wood components, and the generated fractions, as well as standardized methods for evaluating and reporting yields are desired. At the end of this review, a discourse on how such standardizations can be implemented is given.
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Affiliation(s)
- Maxim V. Galkin
- Department of Organic Chemistry
- Stockholm University
- Stockholm
- Sweden
| | | | - Ulrica Edlund
- Fiber and Polymer Technology
- Royal Institute of Technology (KTH)
- SE-100 44 Stockholm
- Sweden
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24
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Mello BL, Alessi AM, Riaño-Pachón DM, deAzevedo ER, Guimarães FEG, Espirito Santo MC, McQueen-Mason S, Bruce NC, Polikarpov I. Targeted metatranscriptomics of compost-derived consortia reveals a GH11 exerting an unusual exo-1,4-β-xylanase activity. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:254. [PMID: 29118851 PMCID: PMC5667448 DOI: 10.1186/s13068-017-0944-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 10/24/2017] [Indexed: 05/09/2023]
Abstract
BACKGROUND Using globally abundant crop residues as a carbon source for energy generation and renewable chemicals production stand out as a promising solution to reduce current dependency on fossil fuels. In nature, such as in compost habitats, microbial communities efficiently degrade the available plant biomass using a diverse set of synergistic enzymes. However, deconstruction of lignocellulose remains a challenge for industry due to recalcitrant nature of the substrate and the inefficiency of the enzyme systems available, making the economic production of lignocellulosic biofuels difficult. Metatranscriptomic studies of microbial communities can unveil the metabolic functions employed by lignocellulolytic consortia and identify novel biocatalysts that could improve industrial lignocellulose conversion. RESULTS In this study, a microbial community from compost was grown in minimal medium with sugarcane bagasse sugarcane bagasse as the sole carbon source. Solid-state nuclear magnetic resonance was used to monitor lignocellulose degradation; analysis of metatranscriptomic data led to the selection and functional characterization of several target genes, revealing the first glycoside hydrolase from Carbohydrate Active Enzyme family 11 with exo-1,4-β-xylanase activity. The xylanase crystal structure was resolved at 1.76 Å revealing the structural basis of exo-xylanase activity. Supplementation of a commercial cellulolytic enzyme cocktail with the xylanase showed improvement in Avicel hydrolysis in the presence of inhibitory xylooligomers. CONCLUSIONS This study demonstrated that composting microbiomes continue to be an excellent source of biotechnologically important enzymes by unveiling the diversity of enzymes involved in in situ lignocellulose degradation.
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Affiliation(s)
- Bruno L. Mello
- Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense 400, São Carlos, SP 13560-970 Brazil
| | - Anna M. Alessi
- Department of Biology, University of York, Wentworth Way, York, YO10 5DD UK
| | - Diego M. Riaño-Pachón
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol, Centro Nacional de Pesquisa em Energia e Materiais, Rua Giuseppe Máximo Scalfaro 10000, Campinas, SP 13083-100 Brazil
- Laboratório de Biologia de Sistemas Regulatórios, Departamento de Química, Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes 748, São Paulo, SP 05508-000 Brazil
| | - Eduardo R. deAzevedo
- Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense 400, São Carlos, SP 13560-970 Brazil
| | - Francisco E. G. Guimarães
- Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense 400, São Carlos, SP 13560-970 Brazil
| | - Melissa C. Espirito Santo
- Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense 400, São Carlos, SP 13560-970 Brazil
| | | | - Neil C. Bruce
- Department of Biology, University of York, Wentworth Way, York, YO10 5DD UK
| | - Igor Polikarpov
- Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense 400, São Carlos, SP 13560-970 Brazil
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25
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Ferrini P, Rezende CA, Rinaldi R. Catalytic Upstream Biorefining through Hydrogen Transfer Reactions: Understanding the Process from the Pulp Perspective. CHEMSUSCHEM 2016; 9:3171-3180. [PMID: 27767259 DOI: 10.1002/cssc.201601121] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Indexed: 05/14/2023]
Abstract
Catalytic upstream biorefining (CUB) encompasses processes for plant biomass deconstruction through the early-stage conversion of lignin by the action of a hydrogenation catalyst. CUB processes produce lignin as an extensively depolymerised product (i.e., a viscous lignin oil) and render highly delignified pulps. In this report, we examine CUB from the pulp perspective. Notably, Raney Ni plays an indirect role in the processes that occur within the lignocellulose matrix. As there are negligible points of contact between the poplar wood chips and Raney Ni, the catalyst action is limited to the species leached from the matrix into the liquor. Nevertheless, the substantial changes in the liquor composition (through the decomposition of carboxylic acids and H-transfer reductive processes on the lignin fragments) have significant implications for the pulp composition, degree of polymerisation and morphology. Compared with organosolv pulps, CUB pulps show higher xylan retention, higher delignification, and higher polymerisation degree. Moreover, the correlation between these properties and the performance of the enzymatic hydrolyses of CUB and organosolv pulps reveals that the high susceptibility of CUB pulps is mostly caused by their lower residual lignin contents.
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Affiliation(s)
- Paola Ferrini
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Camila A Rezende
- Institute of Chemistry, State University of Campinas, P.O. Box 6154, 13083-970, Campinas, SP, Brazil
| | - Roberto Rinaldi
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, SW7 2AZ, London, United Kingdom
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26
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Song HT, Gao Y, Yang YM, Xiao WJ, Liu SH, Xia WC, Liu ZL, Yi L, Jiang ZB. Synergistic effect of cellulase and xylanase during hydrolysis of natural lignocellulosic substrates. BIORESOURCE TECHNOLOGY 2016; 219:710-715. [PMID: 27560367 DOI: 10.1016/j.biortech.2016.08.035] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 08/10/2016] [Accepted: 08/11/2016] [Indexed: 05/22/2023]
Abstract
Synergistic combination of cellulase and xylanase has been performed on pre-treated substrates in many previous studies, while few on natural substrates. In this study, three unpretreated lignocellulosic substrates were studied, including corncob, corn stover, and rice straw. The results indicated that when the mixed cellulase and xylanase were applied, reducing sugar concentrations were calculated as 19.53, 15.56, and 17.35mg/ml, respectively, based on the 3,5 dinitrosalicylic acid (DNS) method. Compared to the treatment with only cellulose, the hydrolysis yields caused by mixed cellulase and xylanase were improved by 133%, 164%, and 545%, respectively. In addition, the conversion yield of corncob, corn stover, and rice straw by cellulase-xylanase co-treatment reached 43.9%, 48.5%, and 40.2%, respectively, based on HPLC analysis, which confirmed the synergistic effect of cellulase-xylanase that was much higher than either of the single enzyme treatment. The substrate morphology was also evaluated to explore the synergistic mechanism of cellulase-xylanase.
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Affiliation(s)
- Hui-Ting Song
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, PR China; College of Resources and Environmental Science, Hubei University, Wuhan 430062, PR China.
| | - Yuan Gao
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, PR China.
| | - Yi-Min Yang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, PR China.
| | - Wen-Jing Xiao
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, PR China.
| | - Shi-Hui Liu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, PR China.
| | - Wu-Cheng Xia
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, PR China.
| | - Zi-Lu Liu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, PR China.
| | - Li Yi
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, PR China.
| | - Zheng-Bing Jiang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-Resources, Hubei University, Wuhan 430062, PR China; Hubei Key Laboratory of Industrial Biotechnology, College of Life Science, Hubei University, Wuhan 430062, PR China.
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27
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Lin CY, Jakes JE, Donohoe BS, Ciesielski PN, Yang H, Gleber SC, Vogt S, Ding SY, Peer WA, Murphy AS, McCann MC, Himmel ME, Tucker MP, Wei H. Directed plant cell-wall accumulation of iron: embedding co-catalyst for efficient biomass conversion. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:225. [PMID: 27777626 PMCID: PMC5073452 DOI: 10.1186/s13068-016-0639-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 10/08/2016] [Indexed: 05/14/2023]
Abstract
BACKGROUND Plant lignocellulosic biomass is an abundant, renewable feedstock for the production of biobased fuels and chemicals. Previously, we showed that iron can act as a co-catalyst to improve the deconstruction of lignocellulosic biomass. However, directly adding iron catalysts into biomass prior to pretreatment is diffusion limited, and increases the cost of biorefinery operations. Recently, we developed a new strategy for expressing iron-storage protein ferritin intracellularly to accumulate iron as a catalyst for the downstream deconstruction of lignocellulosic biomass. In this study, we extend this approach by fusing the heterologous ferritin gene with a signal peptide for secretion into Arabidopsis cell walls (referred to here as FerEX). RESULTS The transgenic Arabidopsis plants. FerEX. accumulated iron under both normal and iron-fertilized growth conditions; under the latter (iron-fertilized) condition, FerEX transgenic plants showed an increase in plant height and dry weight by 12 and 18 %, respectively, compared with the empty vector control plants. The SDS- and native-PAGE separation of cell-wall protein extracts followed by Western blot analyses confirmed the extracellular expression of ferritin in FerEX plants. Meanwhile, Perls' Prussian blue staining and X-ray fluorescence microscopy (XFM) maps revealed iron depositions in both the secondary and compound middle lamellae cell-wall layers, as well as in some of the corner compound middle lamella in FerEX. Remarkably, their harvested biomasses showed enhanced pretreatability and digestibility, releasing, respectively, 21 % more glucose and 34 % more xylose than the empty vector control plants. These values are significantly higher than those of our recently obtained ferritin intracellularly expressed plants. CONCLUSIONS This study demonstrated that extracellular expression of ferritin in Arabidopsis can produce plants with increased growth and iron accumulation, and reduced thermal and enzymatic recalcitrance. The results are attributed to the intimate colocation of the iron co-catalyst and the cellulose and hemicellulose within the plant cell-wall region, supporting the genetic modification strategy for incorporating conversion catalysts into energy crops prior to harvesting or processing at the biorefinery.
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Affiliation(s)
- Chien-Yuan Lin
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Joseph E. Jakes
- Forest Biopolymer Science and Engineering, USDA Forest Service, Forest Products Laboratory, Madison, WI 53726 USA
| | - Bryon S. Donohoe
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Peter N. Ciesielski
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Haibing Yang
- Department of Biological Science, Purdue University, West Lafayette, IN 47907 USA
| | - Sophie-Charlotte Gleber
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 USA
| | - Stefan Vogt
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 USA
| | - Shi-You Ding
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
- Department of Plant Biology, Michigan State University, East Lansing, MI 48824 USA
| | - Wendy A. Peer
- Department of Environmental Science and Technology, University of Maryland, College Park, MD 20742 USA
| | - Angus S. Murphy
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD 20742 USA
| | - Maureen C. McCann
- Department of Biological Science, Purdue University, West Lafayette, IN 47907 USA
| | - Michael E. Himmel
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Melvin P. Tucker
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
| | - Hui Wei
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA
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28
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Choong FX, Bäck M, Steiner SE, Melican K, Nilsson KPR, Edlund U, Richter-Dahlfors A. Nondestructive, real-time determination and visualization of cellulose, hemicellulose and lignin by luminescent oligothiophenes. Sci Rep 2016; 6:35578. [PMID: 27759105 PMCID: PMC5069672 DOI: 10.1038/srep35578] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/30/2016] [Indexed: 11/17/2022] Open
Abstract
Enabling technologies for efficient use of the bio-based feedstock are crucial to the replacement of oil-based products. We investigated the feasibility of luminescent conjugated oligothiophenes (LCOs) for non-destructive, rapid detection and quality assessment of lignocellulosic components in complex biomass matrices. A cationic pentameric oligothiophene denoted p-HTEA (pentamer hydrogen thiophene ethyl amine) showed unique binding affinities to cellulose, lignin, hemicelluloses, and cellulose nanofibrils in crystal, liquid and paper form. We exploited this finding using spectrofluorometric methods and fluorescence confocal laser scanning microscopy, for sensitive, simultaneous determination of the structural and compositional complexities of native lignocellulosic biomass. With exceptional photostability, p-HTEA is also demonstrated as a dynamic sensor for real-time monitoring of enzymatic cellulose degradation in cellulolysis. These results demonstrate the use of p-HTEA as a non-destructive tool for the determination of cellulose, hemicellulose and lignin in complex biomass matrices, thereby aiding in the optimization of biomass-converting technologies.
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Affiliation(s)
- Ferdinand X Choong
- Swedish Medical Nanoscience Center, Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Marcus Bäck
- Division of Chemistry, Department of Physics, Chemistry and Biology, Linköping University, Linköping, SE-581 83, Sweden
| | - Svava E Steiner
- Swedish Medical Nanoscience Center, Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - Keira Melican
- Swedish Medical Nanoscience Center, Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77, Sweden
| | - K Peter R Nilsson
- Division of Chemistry, Department of Physics, Chemistry and Biology, Linköping University, Linköping, SE-581 83, Sweden
| | - Ulrica Edlund
- Fiber and Polymer Technology, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Agneta Richter-Dahlfors
- Swedish Medical Nanoscience Center, Department of Neuroscience, Karolinska Institutet, Stockholm, SE-171 77, Sweden
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29
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Templeton DW, Sluiter JB, Sluiter A, Payne C, Crocker DP, Tao L, Wolfrum E. Long-term variability in sugarcane bagasse feedstock compositional methods: sources and magnitude of analytical variability. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:223. [PMID: 27777625 PMCID: PMC5069941 DOI: 10.1186/s13068-016-0621-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Accepted: 09/22/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND In an effort to find economical, carbon-neutral transportation fuels, biomass feedstock compositional analysis methods are used to monitor, compare, and improve biofuel conversion processes. These methods are empirical, and the analytical variability seen in the feedstock compositional data propagates into variability in the conversion yields, component balances, mass balances, and ultimately the minimum ethanol selling price (MESP). We report the average composition and standard deviations of 119 individually extracted National Institute of Standards and Technology (NIST) bagasse [Reference Material (RM) 8491] run by seven analysts over 7 years. Two additional datasets, using bulk-extracted bagasse (containing 58 and 291 replicates each), were examined to separate out the effects of batch, analyst, sugar recovery standard calculation method, and extractions from the total analytical variability seen in the individually extracted dataset. We believe this is the world's largest NIST bagasse compositional analysis dataset and it provides unique insight into the long-term analytical variability. Understanding the long-term variability of the feedstock analysis will help determine the minimum difference that can be detected in yield, mass balance, and efficiency calculations. RESULTS The long-term data show consistent bagasse component values through time and by different analysts. This suggests that the standard compositional analysis methods were performed consistently and that the bagasse RM itself remained unchanged during this time period. The long-term variability seen here is generally higher than short-term variabilities. It is worth noting that the effect of short-term or long-term feedstock compositional variability on MESP is small, about $0.03 per gallon. CONCLUSIONS The long-term analysis variabilities reported here are plausible minimum values for these methods, though not necessarily average or expected variabilities. We must emphasize the importance of training and good analytical procedures needed to generate this data. When combined with a robust QA/QC oversight protocol, these empirical methods can be relied upon to generate high-quality data over a long period of time.
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Affiliation(s)
- David W. Templeton
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401-3393 USA
| | - Justin B. Sluiter
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401-3393 USA
| | - Amie Sluiter
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401-3393 USA
| | - Courtney Payne
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401-3393 USA
| | - David P. Crocker
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401-3393 USA
| | - Ling Tao
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401-3393 USA
| | - Ed. Wolfrum
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401-3393 USA
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Lischeske JJ, Crawford NC, Kuhn E, Nagle NJ, Schell DJ, Tucker MP, McMillan JD, Wolfrum EJ. Assessing pretreatment reactor scaling through empirical analysis. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:213. [PMID: 27766117 PMCID: PMC5057393 DOI: 10.1186/s13068-016-0620-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 09/22/2016] [Indexed: 05/24/2023]
Abstract
BACKGROUND Pretreatment is a critical step in the biochemical conversion of lignocellulosic biomass to fuels and chemicals. Due to the complexity of the physicochemical transformations involved, predictively scaling up technology from bench- to pilot-scale is difficult. This study examines how pretreatment effectiveness under nominally similar reaction conditions is influenced by pretreatment reactor design and scale using four different pretreatment reaction systems ranging from a 3 g batch reactor to a 10 dry-ton/days continuous reactor. The reactor systems examined were an automated solvent extractor (ASE), steam explosion reactor (SER), ZipperClave®Reactor (ZCR), and large continuous horizontal screw reactor (LHR). To our knowledge, this is the first such study performed on pretreatment reactors across a range of reaction conditions and at different reactor scales. RESULTS The comparative pretreatment performance results obtained for each reactor system were used to develop response surface models for total xylose yield after pretreatment and total sugar yield after pretreatment followed by enzymatic hydrolysis. Near- and very-near-optimal regions were defined as the set of conditions that the model identified as producing yields within one and two standard deviations of the optimum yield. Optimal conditions identified in the smallest scale system (the ASE) were within the near-optimal region of the largest scale reactor system evaluated. The maximum total sugar yields for the ASE and LHR were [Formula: see text], while [Formula: see text] was the optimum observed in the ZipperClave. CONCLUSIONS The optimum condition identified using the automated and less costly to operate ASE system was within the very-near-optimal space for the total xylose yield of both the ZCR and the LHR, and was within the near-optimal space for total sugar yield for the LHR. This indicates that the ASE is a good tool for cost effectively finding near-optimal conditions for operating pilot-scale systems. Additionally, using a severity factor approach to optimization was found to be inadequate compared to a multivariate optimization method. Finally, the ASE and the LHR were able to enable significantly higher total sugar yields after enzymatic hydrolysis relative to the ZCR, despite having similar optimal conditions and total xylose yields. This underscores the importance of mechanical disruption during pretreatment to improvement of enzymatic digestibility.
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Affiliation(s)
- James J. Lischeske
- National Renewable Energy Laboratory, National Bioenergy Center, 15013 Denver West Parkway, Golden, CO USA
| | - Nathan C. Crawford
- National Renewable Energy Laboratory, National Bioenergy Center, 15013 Denver West Parkway, Golden, CO USA
| | - Erik Kuhn
- National Renewable Energy Laboratory, National Bioenergy Center, 15013 Denver West Parkway, Golden, CO USA
| | - Nicholas J. Nagle
- National Renewable Energy Laboratory, National Bioenergy Center, 15013 Denver West Parkway, Golden, CO USA
| | - Daniel J. Schell
- National Renewable Energy Laboratory, National Bioenergy Center, 15013 Denver West Parkway, Golden, CO USA
| | - Melvin P. Tucker
- National Renewable Energy Laboratory, National Bioenergy Center, 15013 Denver West Parkway, Golden, CO USA
| | - James D. McMillan
- National Renewable Energy Laboratory, National Bioenergy Center, 15013 Denver West Parkway, Golden, CO USA
| | - Edward J. Wolfrum
- National Renewable Energy Laboratory, National Bioenergy Center, 15013 Denver West Parkway, Golden, CO USA
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Bhagia S, Nunez A, Wyman CE, Kumar R. Robustness of two-step acid hydrolysis procedure for composition analysis of poplar. BIORESOURCE TECHNOLOGY 2016; 216:1077-1082. [PMID: 27282557 DOI: 10.1016/j.biortech.2016.04.138] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 04/27/2016] [Accepted: 04/28/2016] [Indexed: 06/06/2023]
Abstract
The NREL standard procedure for lignocellulosic biomass composition has two steps: primary hydrolysis in 72% wt sulfuric acid at 30°C for 1h followed by secondary hydrolysis of the slurry in 4wt% acid at 121°C for 1h. Although pointed out in the NREL procedure, the impact of particle size on composition has never been shown. In addition, the effects of primary hydrolysis time and separation of solids prior to secondary hydrolysis on composition have never been shown. Using poplar, it was found that particle sizes less than 0.250mm significantly lowered the glucan content and increased the Klason lignin but did not affect xylan, acetate, or acid soluble lignin contents. Composition was unaffected for primary hydrolysis time between 30 and 90min. Moreover, separating solids prior to secondary hydrolysis had negligible effect on composition suggesting that lignin and polysaccharides are completely separated in the primary hydrolysis stage.
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Affiliation(s)
- Samarthya Bhagia
- Department of Chemical and Environmental Engineering, Bourns College of Engineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; Center for Environmental Research and Technology, Bourns College of Engineering, University of California Riverside, 1084 Columbia Avenue, Riverside, CA 92507, USA; BioEnergy Science Center (BESC), Oak Ridge National Laboratory (ORNL), PO Box 2008 MS6341, Oak Ridge, TN 37831, USA
| | - Angelica Nunez
- Department of Chemical and Environmental Engineering, Bourns College of Engineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; Center for Environmental Research and Technology, Bourns College of Engineering, University of California Riverside, 1084 Columbia Avenue, Riverside, CA 92507, USA
| | - Charles E Wyman
- Department of Chemical and Environmental Engineering, Bourns College of Engineering, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; Center for Environmental Research and Technology, Bourns College of Engineering, University of California Riverside, 1084 Columbia Avenue, Riverside, CA 92507, USA; BioEnergy Science Center (BESC), Oak Ridge National Laboratory (ORNL), PO Box 2008 MS6341, Oak Ridge, TN 37831, USA.
| | - Rajeev Kumar
- Center for Environmental Research and Technology, Bourns College of Engineering, University of California Riverside, 1084 Columbia Avenue, Riverside, CA 92507, USA; BioEnergy Science Center (BESC), Oak Ridge National Laboratory (ORNL), PO Box 2008 MS6341, Oak Ridge, TN 37831, USA
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Gujjala LKS, Bandyopadhyay TK, Banerjee R. Kinetic modelling of laccase mediated delignification of Lantana camara. BIORESOURCE TECHNOLOGY 2016; 212:47-54. [PMID: 27082268 DOI: 10.1016/j.biortech.2016.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/01/2016] [Accepted: 04/02/2016] [Indexed: 06/05/2023]
Abstract
Enzymatic delignification is seen as a green step in biofuels production owing to its specificity towards lignin and its proper understanding requires a kinetic study to decipher intricate details of the process such as thermodynamic parameters viz., activation energy, entropy change and enthalpy change. A system of two coupled kinetic models has been constructed to model laccase mediated delignification of Lantana camara. From the simulated output, activation energy was predicted to be 45.56 and 56.06 kJ/mol, entropy change was observed to be 1.08 × 10(2) and 1.05 × 10(2)cal/mol-K and enthalpy change was determined to be 3.33 × 10(4) and 3.20 × 10(4)cal/mol, respectively from Tessier's and Michaelis Menten model. While comparing the prediction efficiency, it was noticed that Tessier's model gave better performance. Sensitivity analysis was also conducted and it was observed that the model was most sensitive towards temperature dependent kinetic constants.
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Affiliation(s)
- Lohit K S Gujjala
- Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur 721 302, India
| | - Tapas K Bandyopadhyay
- Metallurgical & Materials Engineering Department, Indian Institute of Technology, Kharagpur 721 302, India
| | - Rintu Banerjee
- Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur 721 302, India; Agricultural & Food Engineering Department, Indian Institute of Technology, Kharagpur 721 302, India.
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Padmanabhan S, Schwyter P, Liu Z, Poon G, Bell AT, Prausnitz JM. Delignification of miscanthus using ethylenediamine (EDA) with or without ammonia and subsequent enzymatic hydrolysis to sugars. 3 Biotech 2016; 6:23. [PMID: 28330098 PMCID: PMC4711287 DOI: 10.1007/s13205-015-0344-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 08/03/2015] [Indexed: 12/01/2022] Open
Abstract
Pretreatment of miscanthus is essential for efficient enzymatic
production of cellulosic ethanol. This study reports a possible pretreatment method
for miscanthus using aqueous ethylenediamine (EDA) for 30 min at 180 °C with or
without ammonia. The mass ratio of miscanthus to EDA was varied from 1:3, 1:1, and
1:0.5, keeping the mass ratio of miscanthus to liquid (EDA + Water) constant at 1:8.
The ammonia-to-miscanthus ratio was 1:0.25. After pretreatment with a ratio of 1:3
miscanthus to EDA, about 75 % of the lignin was removed from the raw miscanthus with
90 % retention of cellulose and 50 % of hemicellulose in the recovered solid.
Enzymatic hydrolysis of the recovered solid miscanthus gave 63 % glucose and 62 %
xylose conversion after 72 h. EDA provides an effective pretreatment for miscanthus,
achieving good delignification and enhanced sugar yield by enzyme hydrolysis.
Results using aqueous EDA with or without ammonia are much better than those using
hot water and compare favorably with those using aqueous ammonia. The
delignification efficiency of EDA pretreatment is high compared to that for
hot-water pretreatment and is nearly as efficient as that obtained for
aqueous-ammonia pretreatment.
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Affiliation(s)
- Sasisanker Padmanabhan
- Energy Biosciences Institute, University of California, Berkeley, CA, 94720-1462, USA.
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720-1462, USA.
- Praj Matrix R & D Center, Division of Praj Industries Ltd, Pune, 412115, India.
| | - Philippe Schwyter
- Energy Biosciences Institute, University of California, Berkeley, CA, 94720-1462, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720-1462, USA
| | - Zhongguo Liu
- Energy Biosciences Institute, University of California, Berkeley, CA, 94720-1462, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720-1462, USA
| | - Geoffrey Poon
- Energy Biosciences Institute, University of California, Berkeley, CA, 94720-1462, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720-1462, USA
| | - Alexis T Bell
- Energy Biosciences Institute, University of California, Berkeley, CA, 94720-1462, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720-1462, USA
| | - John M Prausnitz
- Energy Biosciences Institute, University of California, Berkeley, CA, 94720-1462, USA.
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720-1462, USA.
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Templeton DW, Wolfrum EJ, Yen JH, Sharpless KE. Compositional Analysis of Biomass Reference Materials: Results from an Interlaboratory Study. BIOENERGY RESEARCH 2016; 9:303-314. [PMID: 27019676 PMCID: PMC4807399 DOI: 10.1007/s12155-015-9675-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Biomass compositional methods are used to compare different lignocellulosic feedstocks, to measure component balances around unit operations and to determine process yields and therefore the economic viability of biomass-to-biofuel processes. Four biomass reference materials (RMs NIST 8491-8494) were prepared and characterized, via an interlaboratory comparison exercise in the early 1990s to evaluate biomass summative compositional methods, analysts, and laboratories. Having common, uniform, and stable biomass reference materials gives the opportunity to assess compositional data compared to other analysts, to other labs, and to a known compositional value. The expiration date for the original characterization of these RMs was reached and an effort to assess their stability and recharacterize the reference values for the remaining material using more current methods of analysis was initiated. We sent samples of the four biomass RMs to 11 academic, industrial, and government laboratories, familiar with sulfuric acid compositional methods, for recharacterization of the component reference values. In this work, we have used an expanded suite of analytical methods that are more appropriate for herbaceous feedstocks, to recharacterize the RMs' compositions. We report the median values and the expanded uncertainty values for the four RMs on a dry-mass, whole-biomass basis. The original characterization data has been recalculated using median statistics to facilitate comparisons with this data. We found improved total component closures for three out of the four RMs compared to the original characterization, and the total component closures were near 100 %, which suggests that most components were accurately measured and little double counting occurred. The major components were not statistically different in the recharacterization which suggests that the biomass materials are stable during storage and that additional components, not seen in the original characterization, were quantified here.
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Affiliation(s)
- David W. Templeton
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, MS 3512, Golden, CO 80401-3305, USA
| | - Edward J. Wolfrum
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, MS 3512, Golden, CO 80401-3305, USA
| | - James H. Yen
- Statistical Engineering Division, National Institute of Standards and Technology, 100 Bureau Drive, Stop 8980, Gaithersburg, MD 20899-8980, USA
| | - Katherine E. Sharpless
- Chemical Sciences Division, National Institute of Standards and Technology, 100 Bureau Drive, Stop 8390, Gaithersburg, MD 20899-8390, USA
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Montella S, Balan V, da Costa Sousa L, Gunawan C, Giacobbe S, Pepe O, Faraco V. Saccharification of newspaper waste after ammonia fiber expansion or extractive ammonia. AMB Express 2016; 6:18. [PMID: 26936848 PMCID: PMC4775715 DOI: 10.1186/s13568-016-0189-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Accepted: 02/23/2016] [Indexed: 11/10/2022] Open
Abstract
The lignocellulosic fractions of municipal solid waste (MSW) can be used as renewable resources due to the widespread availability, predictable and low pricing and suitability for most conversion technologies. In particular, after the typical paper recycling loop, the newspaper waste (NW) could be further valorized as feedstock in biorefinering industry since it still contains up to 70 % polysaccharides. In this study, two different physicochemical methods-ammonia fiber expansion (AFEX) and extractive ammonia (EA) were tested for the pretraetment of NW. Furthermore, based on the previously demonstrated ability of the recombinant enzymes endocellulase rCelStrep, α-L-arabinofuranosidase rPoAbf and its evolved variant rPoAbf F435Y/Y446F to improve the saccharification of different lignocellulosic pretreated biomasses (such as corn stover and Arundo donax), in this study these enzymes were tested for the hydrolysis of pretreated NW, with the aim of valorizing the lignocellulosic fractions of the MSW. In particular, a mixture of purified enzymes containing cellulases, xylanases and accessory hemicellulases, was chosen as reference mix and rCelStrep and rPoAbf or its variant were replaced to EGI and Larb. The results showed that these enzymatic mixes are not suitable for the hydrolysis of NW after AFEX or EA pretreatment. On the other hand, when the enzymes rCelStrep, rPoAbf and rPoAbf F435Y/Y446F were tested for their effect in hydrolysis of pretreated NW by addition to a commercial enzyme mixture, it was shown that the total polysaccharides conversion yield reached 37.32 % for AFEX pretreated NW by adding rPoAbf to the mix whilst the maximum sugars conversion yield for EA pretreated NW was achieved 40.80 % by adding rCelStrep. The maximum glucan conversion yield obtained (45.61 % for EA pretreated NW by adding rCelStrep to the commercial mix) is higher than or comparable to those reported in recent manuscripts adopting hydrolysis conditions similar to those used in this study.
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Godin B, Nagle N, Sattler S, Agneessens R, Delcarte J, Wolfrum E. Improved sugar yields from biomass sorghum feedstocks: comparing low-lignin mutants and pretreatment chemistries. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:251. [PMID: 27895705 PMCID: PMC5117605 DOI: 10.1186/s13068-016-0667-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 11/11/2016] [Indexed: 05/07/2023]
Abstract
BACKGROUND For biofuel production processes to be economically efficient, it is essential to maximize the production of monomeric carbohydrates from the structural carbohydrates of feedstocks. One strategy for maximizing carbohydrate production is to identify less recalcitrant feedstock cultivars by performing some type of experimental screening on a large and diverse set of candidate materials, or by identifying genetic modifications (random or directed mutations or transgenic plants) that provide decreased recalcitrance. Economic efficiency can also be increased using additional pretreatment processes such as deacetylation, which uses dilute NaOH to remove the acetyl groups of hemicellulose prior to dilute acid pretreatment. In this work, we used a laboratory-scale screening tool that mimics relevant thermochemical pretreatment conditions to compare the total sugar yield of three near-isogenic brown midrib (bmr) mutant lines and the wild-type (WT) sorghum cultivar. We then compared results obtained from the laboratory-scale screening pretreatment assay to a large-scale pretreatment system. RESULTS After pretreatment and enzymatic hydrolysis, the bmr mutants had higher total sugar yields than the WT sorghum cultivar. Increased pretreatment temperatures increased reactivity for all sorghum samples reducing the differences observed at lower reaction temperatures. Deacetylation prior to dilute acid pretreatment increased the total sugar yield for all four sorghum samples, and reduced the differences in total sugar yields among them, but solubilized a sizable fraction of the non-structural carbohydrates. The general trends of increased total sugar yield in the bmr mutant compared to the WT seen at the laboratory scale were observed at the large-scale system. However, in the larger reactor system, the measured total sugar yields were lower and the difference in total sugar yield between the WT and bmr sorghum was larger. CONCLUSIONS Sorghum bmr mutants, which have a reduced lignin content showed higher total sugar yields than the WT cultivar after dilute acid pretreatment and enzymatic hydrolysis. Deacetylation prior to dilute acid pretreatment increased the total sugar yield for all four sorghum samples. However, since deacetylation also solubilizes a large fraction of the non-structural carbohydrates, the ability to derive value from these solubilized sugars will depend greatly on the proposed conversion process.
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Affiliation(s)
- Bruno Godin
- National Bioenergy Center, National Renewable Energy Laboratory (NREL), 15013 Denver West Parkway, Golden, CO 80401 USA
- Valorization of Agricultural Products Department-Biomass, Bioproducts and Energy Unit, Walloon Agricultural Research Center (CRA-W), Chaussée de Namur, 146, 5030 Gembloux, Belgium
| | - Nick Nagle
- National Bioenergy Center, National Renewable Energy Laboratory (NREL), 15013 Denver West Parkway, Golden, CO 80401 USA
| | - Scott Sattler
- Agricultural Research Service (ARS)-Grain, Forage, and Bioenergy Research Unit, United States Department of Agriculture (USDA), University of Nebraska, 251 Filley Hall/Food Industries Complex, East Campus, Lincoln, NE 68583-0937 USA
| | - Richard Agneessens
- Valorization of Agricultural Products Department-Biomass, Bioproducts and Energy Unit, Walloon Agricultural Research Center (CRA-W), Chaussée de Namur, 146, 5030 Gembloux, Belgium
| | - Jérôme Delcarte
- Valorization of Agricultural Products Department-Biomass, Bioproducts and Energy Unit, Walloon Agricultural Research Center (CRA-W), Chaussée de Namur, 146, 5030 Gembloux, Belgium
| | - Edward Wolfrum
- National Bioenergy Center, National Renewable Energy Laboratory (NREL), 15013 Denver West Parkway, Golden, CO 80401 USA
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Turner MF, Heuberger AL, Kirkwood JS, Collins CC, Wolfrum EJ, Broeckling CD, Prenni JE, Jahn CE. Non-targeted Metabolomics in Diverse Sorghum Breeding Lines Indicates Primary and Secondary Metabolite Profiles Are Associated with Plant Biomass Accumulation and Photosynthesis. FRONTIERS IN PLANT SCIENCE 2016; 7:953. [PMID: 27462319 PMCID: PMC4939745 DOI: 10.3389/fpls.2016.00953] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 06/15/2016] [Indexed: 05/02/2023]
Abstract
Metabolomics is an emerging method to improve our understanding of how genetic diversity affects phenotypic variation in plants. Recent studies have demonstrated that genotype has a major influence on biochemical variation in several types of plant tissues, however, the association between metabolic variation and variation in morphological and physiological traits is largely unknown. Sorghum bicolor (L.) is an important food and fuel crop with extensive genetic and phenotypic variation. Sorghum lines have been bred for differing phenotypes beneficial for production of grain (food), stem sugar (food, fuel), and cellulosic biomass (forage, fuel), and these varying phenotypes are the end products of innate metabolic programming which determines how carbon is allocated during plant growth and development. Further, sorghum has been adapted among highly diverse environments. Because of this geographic and phenotypic variation, the sorghum metabolome is expected to be highly divergent; however, metabolite variation in sorghum has not been characterized. Here, we utilize a phenotypically diverse panel of sorghum breeding lines to identify associations between leaf metabolites and morpho-physiological traits. The panel (11 lines) exhibited significant variation for 21 morpho-physiological traits, as well as broader trends in variation by sorghum type (grain vs. biomass types). Variation was also observed for cell wall constituents (glucan, xylan, lignin, ash). Non-targeted metabolomics analysis of leaf tissue showed that 956 of 1181 metabolites varied among the lines (81%, ANOVA, FDR adjusted p < 0.05). Both univariate and multivariate analyses determined relationships between metabolites and morpho-physiological traits, and 384 metabolites correlated with at least one trait (32%, p < 0.05), including many secondary metabolites such as glycosylated flavonoids and chlorogenic acids. The use of metabolomics to explain relationships between two or more morpho-physiological traits was explored and showed chlorogenic and shikimic acid to be associated with photosynthesis, early plant growth and final biomass measures in sorghum. Taken together, this study demonstrates the integration of metabolomics with morpho-physiological datasets to elucidate links between plant metabolism, growth, and architecture.
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Affiliation(s)
- Marie F. Turner
- Department of Bioagricultural Sciences and Pest Management, Colorado State UniversityFort Collins, CO, USA
| | - Adam L. Heuberger
- Department of Horticulture and Landscape Architecture, Colorado State UniversityFort Collins, CO, USA
| | - Jay S. Kirkwood
- Department of Bioagricultural Sciences and Pest Management, Colorado State UniversityFort Collins, CO, USA
- Proteomics and Metabolomics Facility, Colorado State UniversityFort Collins, CO, USA
| | - Carl C. Collins
- Department of Bioagricultural Sciences and Pest Management, Colorado State UniversityFort Collins, CO, USA
| | - Edward J. Wolfrum
- National Renewable Energy Laboratory, National Bioenergy CenterGolden, CO, USA
| | - Corey D. Broeckling
- Proteomics and Metabolomics Facility, Colorado State UniversityFort Collins, CO, USA
| | - Jessica E. Prenni
- Proteomics and Metabolomics Facility, Colorado State UniversityFort Collins, CO, USA
| | - Courtney E. Jahn
- Department of Bioagricultural Sciences and Pest Management, Colorado State UniversityFort Collins, CO, USA
- *Correspondence: Courtney E. Jahn
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Karimi K, Taherzadeh MJ. A critical review of analytical methods in pretreatment of lignocelluloses: Composition, imaging, and crystallinity. BIORESOURCE TECHNOLOGY 2016; 200:1008-18. [PMID: 26614225 DOI: 10.1016/j.biortech.2015.11.022] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 11/07/2015] [Accepted: 11/09/2015] [Indexed: 05/02/2023]
Abstract
Lignocelluloses are widely investigated as renewable substrates to produce biofuels, e.g., ethanol, methane, hydrogen, and butanol, as well as chemicals such as citric acid, lactic acid, and xanthan gum. However, lignocelluloses have a recalcitrance structure to resist microbial and enzymatic attacks; therefore, many physical, thermal, chemical, and biological pretreatment methods have been developed to open up their structure. The efficiency of these pretreatments was studied using a variety of analytical methods that address their image, composition, crystallinity, degree of polymerization, enzyme adsorption/desorption, and accessibility. This paper presents a critical review of the first three categories of these methods as well as their constraints in various applications. The advantages, drawbacks, approaches, practical details, and some points that should be considered in the experimental methods to reach reliable and promising conclusions are also discussed.
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Affiliation(s)
- Keikhosro Karimi
- Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran; Industrial Biotechnology Group, Institute of Biotechnology and Bioengineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
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Westereng B, Cannella D, Wittrup Agger J, Jørgensen H, Larsen Andersen M, Eijsink VG, Felby C. Enzymatic cellulose oxidation is linked to lignin by long-range electron transfer. Sci Rep 2015; 5:18561. [PMID: 26686263 PMCID: PMC4685257 DOI: 10.1038/srep18561] [Citation(s) in RCA: 135] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 11/20/2015] [Indexed: 12/25/2022] Open
Abstract
Enzymatic oxidation of cell wall polysaccharides by lytic polysaccharide monooxygenases (LPMOs) plays a pivotal role in the degradation of plant biomass. While experiments have shown that LPMOs are copper dependent enzymes requiring an electron donor, the mechanism and origin of the electron supply in biological systems are only partly understood. We show here that insoluble high molecular weight lignin functions as a reservoir of electrons facilitating LPMO activity. The electrons are donated to the enzyme by long-range electron transfer involving soluble low molecular weight lignins present in plant cell walls. Electron transfer was confirmed by electron paramagnetic resonance spectroscopy showing that LPMO activity on cellulose changes the level of unpaired electrons in the lignin. The discovery of a long-range electron transfer mechanism links the biodegradation of cellulose and lignin and sheds new light on how oxidative enzymes present in plant degraders may act in concert.
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Affiliation(s)
- Bjørge Westereng
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, 1432 Ås, Norway
- University of Copenhagen, Faculty of Science, Department of Geoscience and Natural Resources Rolighedsvej 23, 1958 Frederiksberg C, Denmark
| | - David Cannella
- University of Copenhagen, Faculty of Science, Department of Geoscience and Natural Resources Rolighedsvej 23, 1958 Frederiksberg C, Denmark
| | - Jane Wittrup Agger
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, 1432 Ås, Norway
| | - Henning Jørgensen
- University of Copenhagen, Faculty of Science, Department of Geoscience and Natural Resources Rolighedsvej 23, 1958 Frederiksberg C, Denmark
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, 2800 Lyngby, Denmark
| | - Mogens Larsen Andersen
- University of Copenhagen, Faculty of Science, Department of Food Science Rolighedsvej 30, 1958 Frederiksberg C, Denmark
| | - Vincent G.H. Eijsink
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, 1432 Ås, Norway
| | - Claus Felby
- University of Copenhagen, Faculty of Science, Department of Geoscience and Natural Resources Rolighedsvej 23, 1958 Frederiksberg C, Denmark
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Prunescu RM, Blanke M, Jakobsen JG, Sin G. Dynamic modeling and validation of a biomass hydrothermal pretreatment process-a demonstration scale study. AIChE J 2015. [DOI: 10.1002/aic.14954] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Remus Mihail Prunescu
- Dept. of Electrical Engineering, Automation and Control Group; Technical University of Denmark; Elektrovej 2800 Kgs. Lyngby Denmark
| | - Mogens Blanke
- Dept. of Electrical Engineering, Automation and Control Group; Technical University of Denmark; Elektrovej 2800 Kgs. Lyngby Denmark
| | - Jon Geest Jakobsen
- Dept. of Process Control and Optimization; DONG Energy Thermal Power A/S; Nesa Allé, 1 2820 Gentofte Denmark
| | - Gürkan Sin
- Dept. of Chemical and Biochemical Engineering; CAPEC-PROCESS, Technical University of Denmark; Søltofts Plads 2800 Kgs. Lyngby Denmark
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Nguyen TY, Cai CM, Kumar R, Wyman CE. Co-solvent pretreatment reduces costly enzyme requirements for high sugar and ethanol yields from lignocellulosic biomass. CHEMSUSCHEM 2015; 8:1716-25. [PMID: 25677100 DOI: 10.1002/cssc.201403045] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 12/07/2014] [Indexed: 05/11/2023]
Abstract
We introduce a new pretreatment called co-solvent-enhanced lignocellulosic fractionation (CELF) to reduce enzyme costs dramatically for high sugar yields from hemicellulose and cellulose, which is essential for the low-cost conversion of biomass to fuels. CELF employs THF miscible with aqueous dilute acid to obtain up to 95 % theoretical yield of glucose, xylose, and arabinose from corn stover even if coupled with enzymatic hydrolysis at only 2 mgenzyme gglucan (-1) . The unusually high saccharification with such low enzyme loadings can be attributed to a very high lignin removal, which is supported by compositional analysis, fractal kinetic modeling, and SEM imaging. Subsequently, nearly pure lignin product can be precipitated by the evaporation of volatile THF for recovery and recycling. Simultaneous saccharification and fermentation of CELF-pretreated solids with low enzyme loadings and Saccharomyces cerevisiae produced twice as much ethanol as that from dilute-acid-pretreated solids if both were optimized for corn stover.
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Affiliation(s)
- Thanh Yen Nguyen
- Center for Environmental Research and Technology (CE-CERT), Bourns College of Engineering, University of California, Riverside, 1084 Columbia Avenue, Riverside, California 92507 (USA), Fax: (+1) 951-781-5790
- Department of Bioengineering, Bourns College of Engineering, University of California, Riverside, 217 Materials Science & Engineering, 900 University Ave., Riverside, CA 92507 (USA)
| | - Charles M Cai
- Center for Environmental Research and Technology (CE-CERT), Bourns College of Engineering, University of California, Riverside, 1084 Columbia Avenue, Riverside, California 92507 (USA), Fax: (+1) 951-781-5790
- Department of Chemical and Environmental Engineering, Bourns College of Engineering, University of California, Riverside, 446 Winston Chung Hall, 900 University Ave., Riverside, CA 92507 (United States)
- BioEnergy Science Center (BESC), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA)
| | - Rajeev Kumar
- Center for Environmental Research and Technology (CE-CERT), Bourns College of Engineering, University of California, Riverside, 1084 Columbia Avenue, Riverside, California 92507 (USA), Fax: (+1) 951-781-5790
- BioEnergy Science Center (BESC), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA)
| | - Charles E Wyman
- Center for Environmental Research and Technology (CE-CERT), Bourns College of Engineering, University of California, Riverside, 1084 Columbia Avenue, Riverside, California 92507 (USA), Fax: (+1) 951-781-5790.
- Department of Bioengineering, Bourns College of Engineering, University of California, Riverside, 217 Materials Science & Engineering, 900 University Ave., Riverside, CA 92507 (USA).
- Department of Chemical and Environmental Engineering, Bourns College of Engineering, University of California, Riverside, 446 Winston Chung Hall, 900 University Ave., Riverside, CA 92507 (United States).
- BioEnergy Science Center (BESC), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (USA).
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Bernardinelli OD, Lima MA, Rezende CA, Polikarpov I, deAzevedo ER. Quantitative (13)C MultiCP solid-state NMR as a tool for evaluation of cellulose crystallinity index measured directly inside sugarcane biomass. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:110. [PMID: 26244055 PMCID: PMC4524013 DOI: 10.1186/s13068-015-0292-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 07/22/2015] [Indexed: 05/03/2023]
Abstract
BACKGROUND The crystallinity index (CI) is often associated with changes in cellulose structure after biological and physicochemical pretreatments. While some results obtained with lignocellulosic biomass demonstrate a progressive increase in the CI as a function of pretreatments, it is also shown that the CI can significantly vary depending on the choice of the measurement method. Besides, the influence of the CI on the recalcitrance of biomass has been controversial for a long time, but the most recent results tend to point out that the efficiency of pretreatments in reducing the recalcitrance is not clearly correlated with the decrease of the CI. Much of this controversy is somewhat associated with the inability to distinguish between the CI of the cellulose inside the biomass and the CI of the full biomass, which contains other amorphous components such as lignin and hemicellulose. RESULTS Cross polarization by multiple contact periods (Multi-CP) method was used to obtain quantitative (13)C solid-state nuclear magnetic resonance (ssNMR) spectra of sugarcane bagasse biomass submitted to two-step pretreatments and/or enzymatic hydrolysis. By comparing the dipolar filtered Multi-CP (13)C NMR spectra of untreated bagasse samples with those of samples submitted to acid pretreatment, we show that a 1% H2SO4-assisted pretreatment was very effective in removing practically all the hemicellulose signals. This led us to propose a spectral editing procedure based on the subtraction of MultiCP spectra of acid-treated biomass from that of the extracted lignin, to obtain a virtually pure cellulose spectrum. Based on this idea, we were able to evaluate the CI of the native cellulose inside the sugarcane bagasse biomass. CONCLUSIONS The results show the validity of the proposed method as a tool for evaluating the variations in the CI of the cellulose inside biomasses of similar kinds. Despite a clear increase in the CI of biomass as measured by X-ray diffraction, no significant variations were observed in the CI of the cellulose inside the biomass after a particular 1% H2SO4/0.25-4% NaOH chemical-assisted pretreatments. The CI of cellulose inside the biomass solid fraction that remained after the enzymatic hydrolysis was also evaluated. The results show a slight increase in crystallinity.
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Affiliation(s)
- Oigres Daniel Bernardinelli
- />Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos, SP 13660-970 Brazil
| | - Marisa Aparecida Lima
- />Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos, SP 13660-970 Brazil
| | - Camila Alves Rezende
- />Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos, SP 13660-970 Brazil
- />Instituto de Química, Universidade de Campinas-UNICAMP, Caixa Postal 6154, Campinas, SP 13084-971 Brazil
| | - Igor Polikarpov
- />Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos, SP 13660-970 Brazil
| | - Eduardo Ribeiro deAzevedo
- />Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos, SP 13660-970 Brazil
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Chen X, Shekiro J, Pschorn T, Sabourin M, Tucker MP, Tao L. Techno-economic analysis of the deacetylation and disk refining process: characterizing the effect of refining energy and enzyme usage on minimum sugar selling price and minimum ethanol selling price. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:173. [PMID: 26516346 PMCID: PMC4625976 DOI: 10.1186/s13068-015-0358-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 10/14/2015] [Indexed: 05/20/2023]
Abstract
BACKGROUND A novel, highly efficient deacetylation and disk refining (DDR) process to liberate fermentable sugars from biomass was recently developed at the National Renewable Energy Laboratory (NREL). The DDR process consists of a mild, dilute alkaline deacetylation step followed by low-energy-consumption disk refining. The DDR corn stover substrates achieved high process sugar conversion yields, at low to modest enzyme loadings, and also produced high sugar concentration syrups at high initial insoluble solid loadings. The sugar syrups derived from corn stover are highly fermentable due to low concentrations of fermentation inhibitors. The objective of this work is to evaluate the economic feasibility of the DDR process through a techno-economic analysis (TEA). RESULTS A large array of experiments designed using a response surface methodology was carried out to investigate the two major cost-driven operational parameters of the novel DDR process: refining energy and enzyme loadings. The boundary conditions for refining energy (128-468 kWh/ODMT), cellulase (Novozyme's CTec3) loading (11.6-28.4 mg total protein/g of cellulose), and hemicellulase (Novozyme's HTec3) loading (0-5 mg total protein/g of cellulose) were chosen to cover the most commercially practical operating conditions. The sugar and ethanol yields were modeled with good adequacy, showing a positive linear correlation between those yields and refining energy and enzyme loadings. The ethanol yields ranged from 77 to 89 gallons/ODMT of corn stover. The minimum sugar selling price (MSSP) ranged from $0.191 to $0.212 per lb of 50 % concentrated monomeric sugars, while the minimum ethanol selling price (MESP) ranged from $2.24 to $2.54 per gallon of ethanol. CONCLUSIONS The DDR process concept is evaluated for economic feasibility through TEA. The MSSP and MESP of the DDR process falls within a range similar to that found with the deacetylation/dilute acid pretreatment process modeled in NREL's 2011 design report. The DDR process is a much simpler process that requires less capital and maintenance costs when compared to conventional chemical pretreatments with pressure vessels. As a result, we feel the DDR process should be considered as an option for future biorefineries with great potential to be more cost-effective.
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Affiliation(s)
- Xiaowen Chen
- />National Bioenergy Center, National Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80127 USA
| | - Joseph Shekiro
- />National Bioenergy Center, National Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80127 USA
| | - Thomas Pschorn
- />Andritz Inc., 3200 Upper Valley Pike, Springfield, OH USA
| | - Marc Sabourin
- />Andritz Inc., 3200 Upper Valley Pike, Springfield, OH USA
| | - Melvin P. Tucker
- />National Bioenergy Center, National Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80127 USA
| | - Ling Tao
- />National Bioenergy Center, National Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80127 USA
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M. Kline L, Labbé N, Boyer C, Edward Yu T, C. English B, A. Larson J. Investigating the impact of biomass quality on near-infrared models for switchgrass feedstocks. AIMS BIOENGINEERING 2015. [DOI: 10.3934/bioeng.2016.1.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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45
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Cantero DA, Dolores Bermejo M, José Cocero M. Reaction engineering for process intensification of supercritical water biomass refining. J Supercrit Fluids 2015. [DOI: 10.1016/j.supflu.2014.07.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Payne CE, Wolfrum EJ. Rapid analysis of composition and reactivity in cellulosic biomass feedstocks with near-infrared spectroscopy. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:43. [PMID: 25834638 PMCID: PMC4381445 DOI: 10.1186/s13068-015-0222-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Accepted: 02/04/2015] [Indexed: 05/02/2023]
Abstract
BACKGROUND Obtaining accurate chemical composition and reactivity (measures of carbohydrate release and yield) information for biomass feedstocks in a timely manner is necessary for the commercialization of biofuels. Our objective was to use near-infrared (NIR) spectroscopy and partial least squares (PLS) multivariate analysis to develop calibration models to predict the feedstock composition and the release and yield of soluble carbohydrates generated by a bench-scale dilute acid pretreatment and enzymatic hydrolysis assay. Major feedstocks included in the calibration models are corn stover, sorghum, switchgrass, perennial cool season grasses, rice straw, and miscanthus. RESULTS We present individual model statistics to demonstrate model performance and validation samples to more accurately measure predictive quality of the models. The PLS-2 model for composition predicts glucan, xylan, lignin, and ash (wt%) with uncertainties similar to primary measurement methods. A PLS-2 model was developed to predict glucose and xylose release following pretreatment and enzymatic hydrolysis. An additional PLS-2 model was developed to predict glucan and xylan yield. PLS-1 models were developed to predict the sum of glucose/glucan and xylose/xylan for release and yield (grams per gram). The release and yield models have higher uncertainties than the primary methods used to develop the models. CONCLUSION It is possible to build effective multispecies feedstock models for composition, as well as carbohydrate release and yield. The model for composition is useful for predicting glucan, xylan, lignin, and ash with good uncertainties. The release and yield models have higher uncertainties; however, these models are useful for rapidly screening sample populations to identify unusual samples.
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Affiliation(s)
- Courtney E Payne
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401 USA
| | - Edward J Wolfrum
- National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401 USA
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Xiao L, Wei H, Himmel ME, Jameel H, Kelley SS. NIR and Py-mbms coupled with multivariate data analysis as a high-throughput biomass characterization technique: a review. FRONTIERS IN PLANT SCIENCE 2014; 5:388. [PMID: 25147552 PMCID: PMC4124520 DOI: 10.3389/fpls.2014.00388] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 07/22/2014] [Indexed: 05/10/2023]
Abstract
Optimizing the use of lignocellulosic biomass as the feedstock for renewable energy production is currently being developed globally. Biomass is a complex mixture of cellulose, hemicelluloses, lignins, extractives, and proteins; as well as inorganic salts. Cell wall compositional analysis for biomass characterization is laborious and time consuming. In order to characterize biomass fast and efficiently, several high through-put technologies have been successfully developed. Among them, near infrared spectroscopy (NIR) and pyrolysis-molecular beam mass spectrometry (Py-mbms) are complementary tools and capable of evaluating a large number of raw or modified biomass in a short period of time. NIR shows vibrations associated with specific chemical structures whereas Py-mbms depicts the full range of fragments from the decomposition of biomass. Both NIR vibrations and Py-mbms peaks are assigned to possible chemical functional groups and molecular structures. They provide complementary information of chemical insight of biomaterials. However, it is challenging to interpret the informative results because of the large amount of overlapping bands or decomposition fragments contained in the spectra. In order to improve the efficiency of data analysis, multivariate analysis tools have been adapted to define the significant correlations among data variables, so that the large number of bands/peaks could be replaced by a small number of reconstructed variables representing original variation. Reconstructed data variables are used for sample comparison (principal component analysis) and for building regression models (partial least square regression) between biomass chemical structures and properties of interests. In this review, the important biomass chemical structures measured by NIR and Py-mbms are summarized. The advantages and disadvantages of conventional data analysis methods and multivariate data analysis methods are introduced, compared and evaluated. This review aims to serve as a guide for choosing the most effective data analysis methods for NIR and Py-mbms characterization of biomass.
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Affiliation(s)
- Li Xiao
- Department of Forest Biomaterials, North Carolina State UniversityRaleigh, NC, USA
| | - Hui Wei
- National Renewable Energy Laboratory, Biosciences CenterGolden, CO, USA
| | - Michael E. Himmel
- National Renewable Energy Laboratory, Biosciences CenterGolden, CO, USA
| | - Hasan Jameel
- Department of Forest Biomaterials, North Carolina State UniversityRaleigh, NC, USA
| | - Stephen S. Kelley
- Department of Forest Biomaterials, North Carolina State UniversityRaleigh, NC, USA
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Wijaya YP, Putra RDD, Widyaya VT, Ha JM, Suh DJ, Kim CS. Comparative study on two-step concentrated acid hydrolysis for the extraction of sugars from lignocellulosic biomass. BIORESOURCE TECHNOLOGY 2014; 164:221-231. [PMID: 24859214 DOI: 10.1016/j.biortech.2014.04.084] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 04/22/2014] [Accepted: 04/23/2014] [Indexed: 06/03/2023]
Abstract
Among all the feasible thermochemical conversion processes, concentrated acid hydrolysis has been applied to break the crystalline structure of cellulose efficiently and scale up for mass production as lignocellulosic biomass fractionation process. Process conditions are optimized by investigating the effect of decrystallization sulfuric acid concentration (65-80 wt%), hydrolysis temperature (80°C and 100°C), hydrolysis reaction time (during two hours), and biomass species (oak wood, pine wood, and empty fruit bunch (EFB) of palm oil) toward sugar recovery. At the optimum process condition, 78-96% sugars out of theoretically extractable sugars have been fractionated by concentrated sulfuric acid hydrolysis of the three different biomass species with 87-90 g/L sugar concentration in the hydrolyzate and highest recalcitrance of pine (softwood) was determined by the correlation of crystallinity index and sugar yield considering reaction severity.
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Affiliation(s)
- Yanuar Philip Wijaya
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Department of Clean Energy and Chemical Engineering, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea
| | - Robertus Dhimas Dhewangga Putra
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Department of Clean Energy and Chemical Engineering, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea
| | - Vania Tanda Widyaya
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Department of Clean Energy and Chemical Engineering, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea
| | - Jeong-Myeong Ha
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Department of Clean Energy and Chemical Engineering, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea
| | - Dong Jin Suh
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Department of Clean Energy and Chemical Engineering, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea
| | - Chang Soo Kim
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Department of Clean Energy and Chemical Engineering, Korea University of Science and Technology, Daejeon 305-350, Republic of Korea.
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Wei H, Fu Y, Magnusson L, Baker JO, Maness PC, Xu Q, Yang S, Bowersox A, Bogorad I, Wang W, Tucker MP, Himmel ME, Ding SY. Comparison of transcriptional profiles of Clostridium thermocellum grown on cellobiose and pretreated yellow poplar using RNA-Seq. Front Microbiol 2014; 5:142. [PMID: 24782837 PMCID: PMC3990059 DOI: 10.3389/fmicb.2014.00142] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 03/19/2014] [Indexed: 01/01/2023] Open
Abstract
The anaerobic, thermophilic bacterium, Clostridium thermocellum, secretes multi-protein enzyme complexes, termed cellulosomes, which synergistically interact with the microbial cell surface and efficiently disassemble plant cell wall biomass. C. thermocellum has also been considered a potential consolidated bioprocessing (CBP) organism due to its ability to produce the biofuel products, hydrogen, and ethanol. We found that C. thermocellum fermentation of pretreated yellow poplar (PYP) produced 30 and 39% of ethanol and hydrogen product concentrations, respectively, compared to fermentation of cellobiose. RNA-seq was used to analyze the transcriptional profiles of these cells. The PYP-grown cells taken for analysis at the late stationary phase showed 1211 genes up-regulated and 314 down-regulated by more than two-fold compared to the cellobiose-grown cells. These affected genes cover a broad spectrum of specific functional categories. The transcriptional analysis was further validated by sub-proteomics data taken from the literature; as well as by quantitative reverse transcription-PCR (qRT-PCR) analyses of selected genes. Specifically, 47 cellulosomal protein-encoding genes, genes for 4 pairs of SigI-RsgI for polysaccharide sensing, 7 cellodextrin ABC transporter genes, and a set of NAD(P)H hydogenase and alcohol dehydrogenase genes were up-regulated for cells growing on PYP compared to cellobiose. These genes could be potential candidates for future studies aimed at gaining insight into the regulatory mechanism of this organism as well as for improvement of C. thermocellum in its role as a CBP organism.
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Affiliation(s)
- Hui Wei
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Yan Fu
- Center for Plant Genomics, Iowa State University Ames, IA, USA
| | - Lauren Magnusson
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA
| | - John O Baker
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Pin-Ching Maness
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Qi Xu
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Shihui Yang
- National Bioenergy Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Andrew Bowersox
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA ; National Bioenergy Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Igor Bogorad
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Wei Wang
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Melvin P Tucker
- National Bioenergy Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Michael E Himmel
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA
| | - Shi-You Ding
- Biosciences Center, National Renewable Energy Laboratory Golden, CO, USA
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50
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Lima MA, Gomez LD, Steele-King CG, Simister R, Bernardinelli OD, Carvalho MA, Rezende CA, Labate CA, deAzevedo ER, McQueen-Mason SJ, Polikarpov I. Evaluating the composition and processing potential of novel sources of Brazilian biomass for sustainable biorenewables production. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:10. [PMID: 24438499 PMCID: PMC4028816 DOI: 10.1186/1754-6834-7-10] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 12/06/2013] [Indexed: 05/04/2023]
Abstract
BACKGROUND The search for promising and renewable sources of carbohydrates for the production of biofuels and other biorenewables has been stimulated by an increase in global energy demand in the face of growing concern over greenhouse gas emissions and fuel security. In particular, interest has focused on non-food lignocellulosic biomass as a potential source of abundant and sustainable feedstock for biorefineries. Here we investigate the potential of three Brazilian grasses (Panicum maximum, Pennisetum purpureum and Brachiaria brizantha), as well as bark residues from the harvesting of two commercial Eucalyptus clones (E. grandis and E. grandis x urophylla) for biofuel production, and compare these to sugarcane bagasse. The effects of hot water, acid, alkaline and sulfite pretreatments (at increasing temperatures) on the chemical composition, morphology and saccharification yields of these different biomass types were evaluated. RESULTS The average yield (per hectare), availability and general composition of all five biomasses were compared. Compositional analyses indicate a high level of hemicellulose and lignin removal in all grass varieties (including sugarcane bagasse) after acid and alkaline pretreatment with increasing temperatures, whilst the biomasses pretreated with hot water or sulfite showed little variation from the control. For all biomasses, higher cellulose enrichment resulted from treatment with sodium hydroxide at 130°C. At 180°C, a decrease in cellulose content was observed, which is associated with high amorphous cellulose removal and 5-hydroxymethyl-furaldehyde production. Morphological analysis showed the effects of different pretreatments on the biomass surface, revealing a high production of microfibrillated cellulose on grass surfaces, after treatment with 1% sodium hydroxide at 130°C for 30 minutes. This may explain the higher hydrolysis yields resulting from these pretreatments, since these cellulosic nanoparticles can be easily accessed and cleaved by cellulases. CONCLUSION Our results show the potential of three Brazilian grasses with high productivity yields as valuable sources of carbohydrates for ethanol production and other biomaterials. Sodium hydroxide at 130°C was found to be the most effective pretreatment for enhanced saccharification yields. It was also efficient in the production of microfibrillated cellulose on grass surfaces, thereby revealing their potential as a source of natural fillers used for bionanocomposites production.
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Affiliation(s)
- Marisa A Lima
- Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos SP 13560-970, Brazil
| | - Leonardo D Gomez
- CNAP, Department of Biology, University of York, York, Heslington YO10 5DD, UK
| | - Clare G Steele-King
- CNAP, Department of Biology, University of York, York, Heslington YO10 5DD, UK
| | - Rachael Simister
- CNAP, Department of Biology, University of York, York, Heslington YO10 5DD, UK
| | - Oigres D Bernardinelli
- Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos SP 13560-970, Brazil
| | - Marcelo A Carvalho
- Embrapa Cerrados, Genética e Melhoramento de Forrageiras, Br 020, Km 18 – Cx. P. 08223, Planaltina DF 73301-970, Brazil
| | - Camila A Rezende
- Instituto de Química, Universidade de Campinas, Caixa Postal 6154, Campinas SP 13083-970, Brazil
| | - Carlos A Labate
- Laboratório Max Feffer de Genética de Plantas, Departamento de Genética -ESALQ, Universidade de São Paulo, Caixa Postal 83, Piracicaba SP 13418-900, Brazil
- Centro Nacional de Pesquisa em Energia e Materiais, Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Campinas, SP, Brazil
| | - Eduardo R deAzevedo
- Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos SP 13560-970, Brazil
| | | | - Igor Polikarpov
- Instituto de Física de São Carlos, Universidade de São Paulo, Caixa Postal 369, São Carlos SP 13560-970, Brazil
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