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Yang L, Zhou Q, Sheng X, Chen X, Hua Y, Lin S, Luo Q, Yu B, Shao T, Wu Y, Chang J, Li Y, Tu M. Harnessing the Genetic Basis of Sorghum Biomass-Related Traits to Facilitate Bioenergy Applications. Int J Mol Sci 2023; 24:14549. [PMID: 37833996 PMCID: PMC10573072 DOI: 10.3390/ijms241914549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/18/2023] [Accepted: 09/21/2023] [Indexed: 10/15/2023] Open
Abstract
The extensive use of fossil fuels and global climate change have raised ever-increasing attention to sustainable development, global food security and the replacement of fossil fuels by renewable energy. Several C4 monocot grasses have excellent photosynthetic ability, stress tolerance and may rapidly produce biomass in marginal lands with low agronomic inputs, thus representing an important source of bioenergy. Among these grasses, Sorghum bicolor has been recognized as not only a promising bioenergy crop but also a research model due to its diploidy, simple genome, genetic diversity and clear orthologous relationship with other grass genomes, allowing sorghum research to be easily translated to other grasses. Although sorghum molecular genetic studies have lagged far behind those of major crops (e.g., rice and maize), recent advances have been made in a number of biomass-related traits to dissect the genetic loci and candidate genes, and to discover the functions of key genes. However, molecular and/or targeted breeding toward biomass-related traits in sorghum have not fully benefited from these pieces of genetic knowledge. Thus, to facilitate the breeding and bioenergy applications of sorghum, this perspective summarizes the bioenergy applications of different types of sorghum and outlines the genetic control of the biomass-related traits, ranging from flowering/maturity, plant height, internode morphological traits and metabolic compositions. In particular, we describe the dynamic changes of carbohydrate metabolism in sorghum internodes and highlight the molecular regulators involved in the different stages of internode carbohydrate metabolism, which affects the bioenergy utilization of sorghum biomass. We argue the way forward is to further enhance our understanding of the genetic mechanisms of these biomass-related traits with new technologies, which will lead to future directions toward tailored designing sorghum biomass traits suitable for different bioenergy applications.
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Affiliation(s)
- Lin Yang
- School of Chemical and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China (Y.W.)
| | - Qin Zhou
- School of Chemical and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China (Y.W.)
| | - Xuan Sheng
- School of Life Science and Technology, Wuhan Polytechnic University, Wuhan 430023, China
| | - Xiangqian Chen
- School of Chemical and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China (Y.W.)
| | - Yuqing Hua
- School of Chemical and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China (Y.W.)
| | - Shuang Lin
- School of Chemical and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China (Y.W.)
| | - Qiyun Luo
- School of Chemical and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China (Y.W.)
| | - Boju Yu
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, The Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science & Technology, Wuhan 430074, China; (B.Y.); (T.S.); (J.C.)
| | - Ti Shao
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, The Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science & Technology, Wuhan 430074, China; (B.Y.); (T.S.); (J.C.)
| | - Yixiao Wu
- School of Chemical and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China (Y.W.)
| | - Junli Chang
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, The Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science & Technology, Wuhan 430074, China; (B.Y.); (T.S.); (J.C.)
| | - Yin Li
- The Genetic Engineering International Cooperation Base of Chinese Ministry of Science and Technology, The Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science & Technology, Wuhan 430074, China; (B.Y.); (T.S.); (J.C.)
| | - Min Tu
- School of Chemical and Environmental Engineering, Wuhan Polytechnic University, Wuhan 430023, China (Y.W.)
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Xiao MZ, Sun Q, Hong S, Chen WJ, Pang B, Du ZY, Yang WB, Sun Z, Yuan TQ. Sweet sorghum for phytoremediation and bioethanol production. JOURNAL OF LEATHER SCIENCE AND ENGINEERING 2021. [DOI: 10.1186/s42825-021-00074-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
AbstractAs an energy crop, sweet sorghum (Sorghum bicolor (L.) Moench) receives increasing attention for phytoremediation and biofuels production due to its good stress tolerance and high biomass with low input requirements. Sweet sorghum possesses wide adaptability, which also has high tolerances to poor soil conditions and drought. Its rapid growth with the large storage of fermentable saccharides in the stalks offers considerable scope for bioethanol production. Additionally, sweet sorghum has heavy metal tolerance and the ability to remove cadmium (Cd) in particular. Therefore, sweet sorghum has great potential to build a sustainable phytoremediation system for Cd-polluted soil remediation and simultaneous ethanol production. To implement this strategy, further efforts are in demand for sweet sorghum in terms of screening superior varieties, improving phytoremediation capacity, and efficient bioethanol production. In this review, current research advances of sweet sorghum including agronomic requirements, phytoremediation of Cd pollution, bioethanol production, and breeding are discussed. Furthermore, crucial problems for future utilization of sweet sorghum stalks after phytoremediation are combed.
Graphical Abstract
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Does Acid Addition Improve Liquid Hot Water Pretreatment of Lignocellulosic Biomass towards Biohydrogen and Biogas Production? SUSTAINABILITY 2020. [DOI: 10.3390/su12218935] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effect of liquid hot water (LHW) pretreatment with or without acid addition (A-LHW) on the production of hydrogen—through dark fermentation (DF)—and methane—through anaerobic digestion (AD)—using three different lignocellulosic biomass types (sunflower straw (SS), grass lawn (GL), and poplar sawdust (PS)) was investigated. Both pretreatment methods led to hemicellulose degradation, but A-LHW resulted in the release of more potential inhibitors (furans and acids) than the LHW pretreatment. Biological hydrogen production (BHP) of the cellulose-rich solid fractions obtained after LHW and A-LHW pretreatment was enhanced compared to the untreated substrates. Due to the release of inhibitory compounds, LHW pretreatment led to higher biochemical methane potential (BMP) than A-LHW pretreatment when both separated fractions (liquid and solid) obtained after pretreatments were used for AD. The recovered energy in the form of methane with LHW pretreatment was 8.4, 12.5, and 7.5 MJ/kg total solids (TS) for SS, GL, and PS, respectively.
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Structural and Thermal Characterization of Novel Organosolv Lignins from Wood and Herbaceous Sources. Processes (Basel) 2020. [DOI: 10.3390/pr8070860] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
This study demonstrates the effects of structural variations of lignins isolated via an organosolv process from different woody and herbaceous feedstocks on their thermal stability profiles. The organosolv lignins were first analysed for impurities, and structural features were determined using the default set of gel permeation chromatography, FT-IR spectroscopy, quantitative 31 P NMR spectroscopy and semi-quantitative 1 H- 13 C HSQC analysis. Pyrolysis-, O 2 - and CO 2 -reactivity of the organosolv lignins were investigated by thermogravimetric analysis (TGA), and volatile formation in various heating cycles was mapped by head-space GC-MS analysis. Revealed reactivities were correlated to the presence of identified impurities and structural features typical for the organosolv lignins. Data suggest that thermogravimetric analysis can eventually be used to delineate a lignin character when basic information regarding its isolation method is available.
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Matsakas L, Raghavendran V, Yakimenko O, Persson G, Olsson E, Rova U, Olsson L, Christakopoulos P. Lignin-first biomass fractionation using a hybrid organosolv - Steam explosion pretreatment technology improves the saccharification and fermentability of spruce biomass. BIORESOURCE TECHNOLOGY 2019; 273:521-528. [PMID: 30471644 DOI: 10.1016/j.biortech.2018.11.055] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 11/13/2018] [Accepted: 11/14/2018] [Indexed: 05/05/2023]
Abstract
For a transition to a sustainable society, fuels, chemicals, and materials should be produced from renewable resources. Lignocellulosic biomass constitutes an abundant and renewable feedstock; however, its successful application in a biorefinery requires efficient fractionation into its components; cellulose, hemicellulose and lignin. Here, we demonstrate that a newly established hybrid organosolv - steam explosion pretreatment can effectively fractionate spruce biomass to yield pretreated solids with high cellulose (72% w/w) and low lignin (delignification up to 79.4% w/w) content. The cellulose-rich pretreated solids present high saccharification yields (up to 61% w/w) making them ideal for subsequent bioconversion processes. Moreover, under high-gravity conditions (22% w/w) we obtained an ethanol titer of 61.7 g/L, the highest so far reported for spruce biomass. Finally, the obtained high-purity lignin is suitable for various advanced applications. In conclusion, hybrid organosolv pretreatment could offer a closed-loop biorefinery while simultaneously adding value to all biomass components.
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Affiliation(s)
- Leonidas Matsakas
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Vijayendran Raghavendran
- Chalmers University of Technology, Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Kemivägen 10, SE-412 96 Göteborg, Sweden
| | - Olga Yakimenko
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Gustav Persson
- Chalmers University of Technology, Department of Physics, Fysikgränd 3, Göteborg SE-412 96, Sweden
| | - Eva Olsson
- Chalmers University of Technology, Department of Physics, Fysikgränd 3, Göteborg SE-412 96, Sweden
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Lisbeth Olsson
- Chalmers University of Technology, Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Kemivägen 10, SE-412 96 Göteborg, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden.
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Katsimpouras C, Dedes G, Bistis P, Kekos D, Kalogiannis KG, Topakas E. Acetone/water oxidation of corn stover for the production of bioethanol and prebiotic oligosaccharides. BIORESOURCE TECHNOLOGY 2018; 270:208-215. [PMID: 30218937 DOI: 10.1016/j.biortech.2018.09.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 09/01/2018] [Accepted: 09/03/2018] [Indexed: 06/08/2023]
Abstract
Ethanol production at high-gravity promise to achieve concentrations over the threshold for an economical distillation process and concurrently reduce water consumption. However, a persisting limitation is the poor mass transfer conditions resulting in low ethanol yields and concentrations. Hereby, the combination of an acetone/water oxidation pretreatment process (AWO) with a liquefaction/saccharification step, using a free-fall mixer, before simultaneous saccharification and fermentation (SSF) can realize ethanol concentrations of up to ca. 74 g/L at a solids content of 20 wt%. The free-fall mixer achieved a biomass slurry viscosity reduction by 87% after only 2 h of enzymatic saccharification, indicating the efficiency of the mixing system. Furthermore, the direct enzymatic treatment of AWO pretreated corn stover (CS) by a GH11 recombinant xylanase, led to the production of xylooligosaccharides (XOS) with prebiotic potential and the removal of insoluble fibers of hemicellulose improved the glucose release of AWOCS by 22%.
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Affiliation(s)
- Constantinos Katsimpouras
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens 15780, Greece
| | - Grigorios Dedes
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens 15780, Greece
| | - Perrakis Bistis
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens 15780, Greece
| | - Dimitrios Kekos
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens 15780, Greece
| | - Konstantinos G Kalogiannis
- Chemical Process and Energy Resources Institute (CPERI), CERTH, 6(th) km Harilaou-Thermi Road, 57001, Thermi, Thessaloniki, Greece
| | - Evangelos Topakas
- Industrial Biotechnology & Biocatalysis Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens 15780, Greece; Biochemical and Chemical Process Engineering, Division of Sustainable Process Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, Sweden.
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Matsakas L, Karnaouri A, Cwirzen A, Rova U, Christakopoulos P. Formation of Lignin Nanoparticles by Combining Organosolv Pretreatment of Birch Biomass and Homogenization Processes. Molecules 2018; 23:E1822. [PMID: 30041408 PMCID: PMC6100471 DOI: 10.3390/molecules23071822] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 07/18/2018] [Accepted: 07/20/2018] [Indexed: 11/16/2022] Open
Abstract
Valorization of lignocellulosic biomass into a biorefinery scheme requires the use of all biomass components; in this, the lignin fraction is often underutilized. Conversion of lignin to nanoparticles is an attractive solution. Here, we investigated the effect of different lignin isolation processes and a post-treatment homogenization step on particle formation. Lignin was isolated from birch chips by using two organosolv processes, traditional organosolv (OS) and hybrid organosolv-steam explosion (HOS-SE) at various ethanol contents. For post-treatment, lignin was homogenized at 500 bar using different ethanol:water ratios. Isolation of lignin with OS resulted in unshaped lignin particles, whereas after HOS-SE, lignin micro-particles were formed directly. Addition of an acidic catalyst during HOS-SE had a negative impact on the particle formation, and the optimal ethanol content was 50⁻60% v/v. Homogenization had a positive effect as it transformed initially unshaped lignin into spherical nanoparticles and reduced the size of the micro-particles isolated by HOS-SE. Ethanol content during homogenization affected the size of the particles, with the optimal results obtained at 75% v/v. We demonstrate that organosolv lignin can be used as an excellent starting material for nanoparticle preparation, with a simple method without the need for extensive chemical modification. It was also demonstrated that tuning of the operational parameters results in nanoparticles of smaller size and with better size homogeneity.
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Affiliation(s)
- Leonidas Matsakas
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden.
| | - Anthi Karnaouri
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden.
| | - Andrzej Cwirzen
- Structural Engineering, Division of Structural and Fire Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden.
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden.
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden.
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Raghavendran V, Nitsos C, Matsakas L, Rova U, Christakopoulos P, Olsson L. A comparative study of the enzymatic hydrolysis of batch organosolv-pretreated birch and spruce biomass. AMB Express 2018; 8:114. [PMID: 29992363 PMCID: PMC6039347 DOI: 10.1186/s13568-018-0643-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 07/05/2018] [Indexed: 01/09/2023] Open
Abstract
A shift towards a sustainable and green society is vital to reduce the negative effects of climate change associated with increased CO2 emissions. Lignocellulosic biomass is both renewable and abundant, but is recalcitrant to deconstruction. Among the methods of pretreatment available, organosolv (OS) delignifies cellulose efficiently, significantly improving its digestibility by enzymes. We have assessed the hydrolysability of the cellulose-rich solid fractions from OS-pretreated spruce and birch at 2% w/v loading (dry matter). Almost complete saccharification of birch was possible with 80 mg enzyme preparation/gsolids (12 FPU/gsolids), while the saccharification yield for spruce was only 70%, even when applying 60 FPU/gsolids. As the cellulose content is enriched by OS, the yield of glucose was higher than in their steam-exploded counterparts. The hydrolysate was a transparent liquid due to the absence of phenolics and was also free from inhibitors. OS pretreatment holds potential for use in a large-scale, closed-loop biorefinery producing fuels from the cellulose fraction and platform chemicals from the hemicellulose and lignin fractions respectively.
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Acid Assisted Organosolv Delignification of Beechwood and Pulp Conversion towards High Concentrated Cellulosic Ethanol via High Gravity Enzymatic Hydrolysis and Fermentation. Molecules 2018; 23:molecules23071647. [PMID: 29976912 PMCID: PMC6099605 DOI: 10.3390/molecules23071647] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 07/02/2018] [Accepted: 07/04/2018] [Indexed: 12/26/2022] Open
Abstract
Background: Future biorefineries will focus on converting low value waste streams to chemical products that are derived from petroleum or refined sugars. Feedstock pretreatment in a simple, cost effective, agnostic manner is a major challenge. Methods: In this work, beechwood sawdust was delignified via an organosolv process, assisted by homogeneous inorganic acid catalysis. Mixtures of water and several organic solvents were evaluated for their performance. Specifically, ethanol (EtOH), acetone (AC), and methyl- isobutyl- ketone (MIBK) were tested with or without the use of homogeneous acid catalysis employing sulfuric, phosphoric, and oxalic acids under relatively mild temperature of 175 °C for one hour. Results: Delignification degrees (DD) higher than 90% were achieved, where both AC and EtOH proved to be suitable solvents for this process. Both oxalic and especially phosphoric acid proved to be good alternative catalysts for replacing sulfuric acid. High gravity simultaneous saccharification and fermentation with an enzyme loading of 8.4 mg/gsolids at 20 wt.% initial solids content reached an ethanol yield of 8.0 w/v%. Conclusions: Efficient delignification combining common volatile solvents and mild acid catalysis allowed for the production of ethanol at high concentration in an efficient manner.
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Matsakas L, Nitsos C, Raghavendran V, Yakimenko O, Persson G, Olsson E, Rova U, Olsson L, Christakopoulos P. A novel hybrid organosolv: steam explosion method for the efficient fractionation and pretreatment of birch biomass. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:160. [PMID: 29930706 PMCID: PMC5992717 DOI: 10.1186/s13068-018-1163-3] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 06/01/2018] [Indexed: 05/02/2023]
Abstract
BACKGROUND The main role of pretreatment is to reduce the natural biomass recalcitrance and thus enhance saccharification yield. A further prerequisite for efficient utilization of all biomass components is their efficient fractionation into well-defined process streams. Currently available pretreatment methods only partially fulfill these criteria. Steam explosion, for example, excels as a pretreatment method but has limited potential for fractionation, whereas organosolv is excellent for delignification but offers poor biomass deconstruction. RESULTS In this article, a hybrid method combining the cooking and fractionation of conventional organosolv pretreatment with the implementation of an explosive discharge of the cooking mixture at the end of pretreatment was developed. The effects of various pretreatment parameters (ethanol content, duration, and addition of sulfuric acid) were evaluated. Pretreatment of birch at 200 °C with 60% v/v ethanol and 1% w/wbiomass H2SO4 was proven to be the most efficient pretreatment condition yielding pretreated solids with 77.9% w/w cellulose, 8.9% w/w hemicellulose, and 7.0 w/w lignin content. Under these conditions, high delignification of 86.2% was demonstrated. The recovered lignin was of high purity, with cellulose and hemicellulose contents not exceeding 0.31 and 3.25% w/w, respectively, and ash to be < 0.17% w/w in all cases, making it suitable for various applications. The pretreated solids presented high saccharification yields, reaching 68% at low enzyme load (6 FPU/g) and complete saccharification at high enzyme load (22.5 FPU/g). Finally, simultaneous saccharification and fermentation (SSF) at 20% w/w solids yielded an ethanol titer of 80 g/L after 192 h, corresponding to 90% of the theoretical maximum. CONCLUSIONS The novel hybrid method developed in this study allowed for the efficient fractionation of birch biomass and production of pretreated solids with high cellulose and low lignin contents. Moreover, the explosive discharge at the end of pretreatment had a positive effect on enzymatic saccharification, resulting in high hydrolyzability of the pretreated solids and elevated ethanol titers in the following high-gravity SSF. To the best of our knowledge, the ethanol concentration obtained with this method is the highest so far for birch biomass.
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Affiliation(s)
- Leonidas Matsakas
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Christos Nitsos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Vijayendran Raghavendran
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 412 96 Göteborg, Sweden
- Present Address: Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield, S10 2TN UK
| | - Olga Yakimenko
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Gustav Persson
- Department of Physics, Chalmers University of Technology, Fysikgränd 3, 412 96 Göteborg, Sweden
| | - Eva Olsson
- Department of Physics, Chalmers University of Technology, Fysikgränd 3, 412 96 Göteborg, Sweden
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
| | - Lisbeth Olsson
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 412 96 Göteborg, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971-87 Luleå, Sweden
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Muraleedharan MN, Zouraris D, Karantonis A, Topakas E, Sandgren M, Rova U, Christakopoulos P, Karnaouri A. Effect of lignin fractions isolated from different biomass sources on cellulose oxidation by fungal lytic polysaccharide monooxygenases. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:296. [PMID: 30386433 PMCID: PMC6204277 DOI: 10.1186/s13068-018-1294-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 10/15/2018] [Indexed: 05/18/2023]
Abstract
BACKGROUND Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that oxidatively cleave recalcitrant lignocellulose in the presence of oxygen or hydrogen peroxide as co-substrate and a reducing agent as electron donor. One of the possible systems that provide electrons to the LPMOs active site and promote the polysaccharide degradation involves the mediation of phenolic agents, such as lignin, low-molecular-weight lignin-derived compounds and other plant phenols. In the present work, the interaction of the bulk insoluble lignin fraction extracted from pretreated biomass with LPMOs and the ability to provide electrons to the active site of the enzymes is studied. RESULTS The catalytic efficiency of three LPMOs, namely MtLPMO9 with C1/C4 regioselectivity, PcLPMO9D which is a C1 active LPMO and NcLPMO9C which is a C4 LPMO, was evaluated in the presence of different lignins. It was correlated with the physicochemical and structural properties of lignins, such as the molecular weight and the composition of aromatic and aliphatic hydroxyl groups. Moreover, the redox potential of lignins was determined with the use of large amplitude Fourier Transform alternating current cyclic voltammetry method and compared to the formal potential of the Cu (II) center in the active site of the LPMOs, providing more information about the lignin-LPMO interaction. The results demonstrated the existence of low-molecular weight lignin-derived compounds that are diffused in the reaction medium, which are able to reduce the enzyme active site and subsequently utilize additional electrons from the insoluble lignin fraction to promote the LPMO oxidative activity. Regarding the bulk lignin fractions, those isolated from the organosolv pretreated materials served as the best candidates in supplying electrons to the soluble compounds and, finally, to the enzymes. This difference, based on biomass pretreatment, was also demonstrated by the activity of LPMOs on natural substrates in the presence and absence of ascorbic acid as additional reducing agent. CONCLUSIONS Lignins can support the action of LPMOs and serve indirectly as electron donors through low-molecular-weight soluble compounds. This ability depends on their physicochemical and structural properties and is related to the biomass source and pretreatment method.
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Affiliation(s)
- Madhu Nair Muraleedharan
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
| | - Dimitrios Zouraris
- Laboratory of Physical Chemistry and Applied Electrochemistry, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
| | - Antonis Karantonis
- Laboratory of Physical Chemistry and Applied Electrochemistry, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
| | - Evangelos Topakas
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
- Biotechnology Laboratory, Department of Synthesis and Development of Industrial Processes, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
| | - Mats Sandgren
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Ulrika Rova
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
| | - Anthi Karnaouri
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
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Katsimpouras C, Zacharopoulou M, Matsakas L, Rova U, Christakopoulos P, Topakas E. Sequential high gravity ethanol fermentation and anaerobic digestion of steam explosion and organosolv pretreated corn stover. BIORESOURCE TECHNOLOGY 2017; 244:1129-1136. [PMID: 28869123 DOI: 10.1016/j.biortech.2017.08.112] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/14/2017] [Accepted: 08/16/2017] [Indexed: 05/15/2023]
Abstract
The present work investigates the suitability of pretreated corn stover (CS) to serve as feedstock for high gravity (HG) ethanol production at solids-content of 24wt%. Steam explosion, with and without the addition of H2SO4, and organosolv pretreated CS samples underwent a liquefaction/saccharification step followed by simultaneous saccharification and fermentation (SSF). Maximum ethanol concentration of ca. 76g/L (78.3% ethanol yield) was obtained from steam exploded CS (SECS) with 0.2% H2SO4. Organosolv pretreated CS (OCS) also resulted in high ethanol concentration of ca. 65g/L (62.3% ethanol yield). Moreover, methane production through anaerobic digestion (AD) was conducted from fermentation residues and resulted in maximum methane yields of ca. 120 and 69mL/g volatile solids (VS) for SECS and OCS samples, respectively. The results indicated that the implementation of a liquefaction/saccharification step before SSF employing a liquefaction reactor seemed to handle HG conditions adequately.
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Affiliation(s)
- Constantinos Katsimpouras
- Industrial Biotechnology & Biocatalysis Group, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens 15780, Greece
| | - Maria Zacharopoulou
- Industrial Biotechnology & Biocatalysis Group, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens 15780, Greece
| | - Leonidas Matsakas
- Biochemical and Chemical Process Engineering, Division of Sustainable Process Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, Sweden
| | - Ulrika Rova
- Biochemical and Chemical Process Engineering, Division of Sustainable Process Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical and Chemical Process Engineering, Division of Sustainable Process Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, Sweden
| | - Evangelos Topakas
- Industrial Biotechnology & Biocatalysis Group, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, Athens 15780, Greece; Biochemical and Chemical Process Engineering, Division of Sustainable Process Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-97187 Luleå, Sweden.
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Ryden P, Efthymiou MN, Tindyebwa TAM, Elliston A, Wilson DR, Waldron KW, Malakar PK. Bioethanol production from spent mushroom compost derived from chaff of millet and sorghum. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:195. [PMID: 28785311 PMCID: PMC5545022 DOI: 10.1186/s13068-017-0880-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 07/26/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND In Uganda, the chaff remaining from threshed panicles of millet and sorghum is a low value, lignocellulose-rich agricultural by-product. Currently, it is used as a substrate for the cultivation of edible Oyster mushrooms (Pleurotus ostreatus). The aim of this study was to assess the potential to exploit the residual post-harvest compost for saccharification and fermentation to produce ethanol. RESULTS Sorghum and millet chaff-derived spent oyster mushroom composts minus large mycelium particles were assessed at small-scale and low substrate concentrations (5% w/v) for optimal severity hydrothermal pre-treatment, enzyme loading and fermentation with robust yeasts to produce ethanol. These conditions were then used as a basis for larger scale assessments with high substrate concentrations (30% w/v). Millet-based compost had a low cellulose content and, at a high substrate concentration, did not liquefy effectively. The ethanol yield was 63.9 g/kg dry matter (DM) of original material with a low concentration (19.6 g/L). Compost derived from sorghum chaff had a higher cellulose content and could be liquefied at high substrate concentration (30% w/v). This enabled selected furfural-resistant yeasts to produce ethanol at up to 186.9 g/kg DM of original material and a concentration of 45.8 g/L. CONCLUSIONS Spent mushroom compost derived from sorghum chaff has the potential to be an industrially useful substrate for producing second-generation bioethanol. This might be improved further through fractionation and exploitation of hemicellulosic moieties, and possibly the exploitation of the mycelium-containing final residue for animal feed. However, spent compost derived from millet does not provide a suitably high concentration of ethanol to make it industrially attractive. Further research on the difficulty in quantitatively saccharifying cellulose from composted millet chaff and other similar substrates such as rice husk is required.
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Affiliation(s)
- Peter Ryden
- The Biorefinery Centre, Quadram Institute Bioscience, Colney, Norwich Research Park, Norwich, NR4 7UA UK
| | - Maria-Nefeli Efthymiou
- The Biorefinery Centre, Quadram Institute Bioscience, Colney, Norwich Research Park, Norwich, NR4 7UA UK
| | - Teddy A. M. Tindyebwa
- School of Biological Sciences, College of Natural Sciences, Makerere University, P.O. Box 7062, Kampala, Uganda
| | - Adam Elliston
- The Biorefinery Centre, Quadram Institute Bioscience, Colney, Norwich Research Park, Norwich, NR4 7UA UK
| | - David R. Wilson
- The Biorefinery Centre, Quadram Institute Bioscience, Colney, Norwich Research Park, Norwich, NR4 7UA UK
| | - Keith W. Waldron
- The Biorefinery Centre, Quadram Institute Bioscience, Colney, Norwich Research Park, Norwich, NR4 7UA UK
| | - Pradeep K. Malakar
- The Biorefinery Centre, Quadram Institute Bioscience, Colney, Norwich Research Park, Norwich, NR4 7UA UK
- College of Food Science and Technology, Shanghai Ocean University, 999 Hu Cheng Huan Road, Shanghai, 201306 People’s Republic of China
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Qiu J, Ma L, Shen F, Yang G, Zhang Y, Deng S, Zhang J, Zeng Y, Hu Y. Pretreating wheat straw by phosphoric acid plus hydrogen peroxide for enzymatic saccharification and ethanol production at high solid loading. BIORESOURCE TECHNOLOGY 2017; 238:174-181. [PMID: 28433905 DOI: 10.1016/j.biortech.2017.04.040] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 04/09/2017] [Accepted: 04/10/2017] [Indexed: 05/26/2023]
Abstract
Wheat straw was pretreated by phosphoric acid plus hydrogen peroxide (PHP) for enzymatic hydrolysis and ethanol fermentation at high solid loadings. Results indicated solid loading could reach 20% with 77.4% cellulose-glucose conversion and glucose concentration of 164.9g/L in hydrolysate, it even was promoted to 25% with only 3.4% decrease on cellulose-glucose conversion as the pretreated-wheat straw was dewatered by air-drying. 72.9% cellulose-glucose conversion still was achieved as the minimized enzyme input of 20mg protein/g cellulose was employed for hydrolysis at 20% solid loading. In the corresponding conditions, 100g wheat straw can yield 11.2g ethanol with concentration of 71.2g/L by simultaneous saccharification and fermentation. Thus, PHP-pretreatment benefitted the glucose or ethanol yield at high solid loadings with lower enzyme input. Additionally, decreases on the maximal cellulase adsorption and the direct-orange/direct-blue indicated drying the PHP-pretreated substrates negatively affected the hydrolysis due to the shrinkage of cellulase-size-accommodable pores.
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Affiliation(s)
- Jingwen Qiu
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China
| | - Lunjie Ma
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China
| | - Fei Shen
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China.
| | - Gang Yang
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China
| | - Yanzong Zhang
- Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China
| | - Shihuai Deng
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China
| | - Jing Zhang
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China
| | - Yongmei Zeng
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China
| | - Yaodong Hu
- Institute of Ecological and Environmental Sciences, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China; Rural Environment Protection Engineering & Technology Center of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan 611130, PR China
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Qi GX, Luo MT, Huang C, Guo HJ, Chen XF, Xiong L, Wang B, Lin XQ, Peng F, Chen XD. Comparison of bacterial cellulose production by Gluconacetobacter xylinus
on bagasse acid and enzymatic hydrolysates. J Appl Polym Sci 2017. [DOI: 10.1002/app.45066] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Gao-Xiang Qi
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- University of Chinese Academy of Sciences; Beijing 100049 People's Republic of China
| | - Mu-Tan Luo
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- University of Chinese Academy of Sciences; Beijing 100049 People's Republic of China
| | - Chao Huang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- CAS Key Laboratory of Renewable Energy; Guangzhou 510640 People's Republic of China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development; Guangzhou 510640 People's Republic of China
| | - Hai-Jun Guo
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- CAS Key Laboratory of Renewable Energy; Guangzhou 510640 People's Republic of China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development; Guangzhou 510640 People's Republic of China
| | - Xue-Fang Chen
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- CAS Key Laboratory of Renewable Energy; Guangzhou 510640 People's Republic of China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development; Guangzhou 510640 People's Republic of China
| | - Lian Xiong
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- CAS Key Laboratory of Renewable Energy; Guangzhou 510640 People's Republic of China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development; Guangzhou 510640 People's Republic of China
| | - Bo Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- University of Chinese Academy of Sciences; Beijing 100049 People's Republic of China
| | - Xiao-Qing Lin
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- CAS Key Laboratory of Renewable Energy; Guangzhou 510640 People's Republic of China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development; Guangzhou 510640 People's Republic of China
| | - Fen Peng
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- CAS Key Laboratory of Renewable Energy; Guangzhou 510640 People's Republic of China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development; Guangzhou 510640 People's Republic of China
| | - Xin-De Chen
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences; Guangzhou 510640 People's Republic of China
- CAS Key Laboratory of Renewable Energy; Guangzhou 510640 People's Republic of China
- Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development; Guangzhou 510640 People's Republic of China
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18
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Karnaouri A, Muraleedharan MN, Dimarogona M, Topakas E, Rova U, Sandgren M, Christakopoulos P. Recombinant expression of thermostable processive MtEG5 endoglucanase and its synergism with MtLPMO from Myceliophthora thermophila during the hydrolysis of lignocellulosic substrates. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:126. [PMID: 28515785 PMCID: PMC5432998 DOI: 10.1186/s13068-017-0813-1] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 05/08/2017] [Indexed: 05/02/2023]
Abstract
BACKGROUND Filamentous fungi are among the most powerful cellulolytic organisms in terrestrial ecosystems. To perform the degradation of lignocellulosic substrates, these microorganisms employ both hydrolytic and oxidative mechanisms that involve the secretion and synergism of a wide variety of enzymes. Interactions between these enzymes occur on the level of saccharification, i.e., the release of neutral and oxidized products, but sometimes also reflected in the substrate liquefaction. Although the synergism regarding the yield of neutral sugars has been extensively studied, further studies should focus on the oxidized sugars, as well as the effect of enzyme combinations on the viscosity properties of the substrates. RESULTS In the present study, the heterologous expression of an endoglucanase (EG) and its combined activity together with a lytic polysaccharide monooxygenase (LPMO), both from the thermophilic fungus Myceliophthora thermophila, are described. The EG gene, belonging to the glycoside hydrolase family 5, was functionally expressed in the methylotrophic yeast Pichia pastoris. The produced MtEG5A (75 kDa) featured remarkable thermal stability and showed high specific activity on microcrystalline cellulose compared to CMC, which is indicative of its processivity properties. The enzyme was capable of releasing high amounts of cellobiose from wheat straw, birch, and spruce biomass. Addition of MtLPMO9 together with MtEG5A showed enhanced enzymatic hydrolysis yields against regenerated amorphous cellulose (PASC) by improving the release not only of the neutral but also of the oxidized sugars. Assessment of activity of MtEG5A on the reduction of viscosity of PASC and pretreated wheat straw using dynamic viscosity measurements revealed that the enzyme is able to perform liquefaction of the model substrate and the natural lignocellulosic material, while when added together with MtLPMO9, no further synergistic effect was observed. CONCLUSIONS The endoglucanase MtEG5A from the thermophilic fungus M. thermophila exhibited excellent properties that render it a suitable candidate for use in biotechnological applications. Its strong synergism with LPMO was reflected in sugars release, but not in substrate viscosity reduction. Based on the level of oxidative sugar formation, this is the first indication of synergy between LPMO and EG reported.
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Affiliation(s)
- Anthi Karnaouri
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
| | - Madhu Nair Muraleedharan
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
| | - Maria Dimarogona
- Biotechnology Laboratory, Department of Synthesis and Development of Industrial Processes, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
| | - Evangelos Topakas
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
- Biotechnology Laboratory, Department of Synthesis and Development of Industrial Processes, School of Chemical Engineering, National Technical University of Athens, Athens, Greece
| | - Ulrika Rova
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
| | - Mats Sandgren
- Department of Chemistry and Biotechnology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, Sweden
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Katsimpouras C, Kalogiannis KG, Kalogianni A, Lappas AA, Topakas E. Production of high concentrated cellulosic ethanol by acetone/water oxidized pretreated beech wood. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:54. [PMID: 28265300 PMCID: PMC5331700 DOI: 10.1186/s13068-017-0737-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 02/17/2017] [Indexed: 05/07/2023]
Abstract
BACKGROUND Lignocellulosic biomass is an abundant and inexpensive resource for biofuel production. Alongside its biotechnological conversion, pretreatment is essential to enable efficient enzymatic hydrolysis by making cellulose susceptible to cellulases. Wet oxidation of biomass, such as acetone/water oxidation, that employs hot acetone, water, and oxygen, has been found to be an attractive pretreatment method for removing lignin while producing less degradation products. The remaining enriched cellulose fraction has the potential to be utilized under high gravity enzymatic saccharification and fermentation processes for the cost-competing production of bioethanol. RESULTS Beech wood residual biomass was pretreated following an acetone/water oxidation process aiming at the production of high concentration of cellulosic ethanol. The effect of pressure, reaction time, temperature, and acetone-to-water ratio on the final composition of the pretreated samples was studied for the efficient utilization of the lignocellulosic feedstock. The optimal conditions were acetone/water ratio 1:1, 40 atm initial pressure of 40 vol% O2 gas, and 64 atm at reaction temperature of 175 °C for 2 h incubation. The pretreated beech wood underwent an optimization step studying the effect of enzyme loading and solids content on the enzymatic liquefaction/saccharification prior to fermentation. In a custom designed free-fall mixer at 50 °C for either 6 or 12 h of prehydrolysis using an enzyme loading of 9 mg/g dry matter at 20 wt% initial solids content, high ethanol concentration of 75.9 g/L was obtained. CONCLUSION The optimization of the pretreatment process allowed the efficient utilization of beech wood residual biomass for the production of high concentrations of cellulosic ethanol, while obtaining lignin that can be upgraded towards high-added-value chemicals. The threshold of 4 wt% ethanol concentration that is required for the sustainable bioethanol production was surpassed almost twofold, underpinning the efficient conversion of biomass to ethanol and bio-based chemicals on behalf of the biorefinery concept.
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Affiliation(s)
- Constantinos Katsimpouras
- Industrial Biotechnology & Biocatalysis Group, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, 15780 Athens, Greece
| | - Konstantinos G. Kalogiannis
- Chemical Process and Energy Resources Institute (CPERI), CERTH, 6th km Harilaou-Thermi Road, Thermi, 57001 Thessalonica, Greece
| | - Aggeliki Kalogianni
- Chemical Process and Energy Resources Institute (CPERI), CERTH, 6th km Harilaou-Thermi Road, Thermi, 57001 Thessalonica, Greece
| | - Angelos A. Lappas
- Chemical Process and Energy Resources Institute (CPERI), CERTH, 6th km Harilaou-Thermi Road, Thermi, 57001 Thessalonica, Greece
| | - Evangelos Topakas
- Industrial Biotechnology & Biocatalysis Group, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str., Zografou Campus, 15780 Athens, Greece
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Acetic acid-catalyzed hydrothermal pretreatment of corn stover for the production of bioethanol at high-solids content. Bioprocess Biosyst Eng 2016; 39:1415-23. [DOI: 10.1007/s00449-016-1618-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 04/24/2016] [Indexed: 10/21/2022]
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Karnaouri A, Matsakas L, Topakas E, Rova U, Christakopoulos P. Development of Thermophilic Tailor-Made Enzyme Mixtures for the Bioconversion of Agricultural and Forest Residues. Front Microbiol 2016; 7:177. [PMID: 26909078 PMCID: PMC4754399 DOI: 10.3389/fmicb.2016.00177] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/01/2016] [Indexed: 11/13/2022] Open
Abstract
Even though the main components of all lignocellulosic feedstocks include cellulose, hemicellulose, as well as the protective lignin matrix, there are some differences in structure, such as in hardwoods and softwoods, which may influence the degradability of the materials. Under this view, various types of biomass might require a minimal set of enzymes that has to be tailor-made. Partially defined complex mixtures that are currently commercially used are not adapted to efficiently degrade different materials, so novel enzyme mixtures have to be customized. Development of these cocktails requires better knowledge about the specific activities involved, in order to optimize hydrolysis. The role of filamentous fungus Myceliophthora thermophila and its complete enzymatic repertoire for the bioconversion of complex carbohydrates has been widely proven. In this study, four core cellulases (MtCBH7, MtCBH6, MtEG5, and MtEG7), in the presence of other four "accessory" enzymes (mannanase, lytic polyssacharide monooxygenase MtGH61, xylanase, MtFae1a) and β-glucosidase MtBGL3, were tested as a nine-component cocktail against one model substrate (phosphoric acid swollen cellulose) and four hydrothermally pretreated natural substrates (wheat straw as an agricultural waste, birch, and spruce biomass, as forest residues). Synergistic interactions among different enzymes were determined using a suitable design of experiments methodology. The results suggest that for the hydrolysis of the pure substrate (PASC), high proportions of MtEG7 are needed for efficient yields. MtCBH7 and MtEG7 are enzymes of major importance during the hydrolysis of pretreated wheat straw, while MtCBH7 plays a crucial role in case of spruce. Cellobiohydrolases MtCBH6 and MtCBH7 act in combination and are key enzymes for the hydrolysis of the hardwood (birch). Optimum combinations were predicted from suitable statistical models which were able to further increase hydrolysis yields, suggesting that tailor-made enzyme mixtures targeted toward a particular residual biomass can help maximize hydrolysis yields. The present work demonstrates the change from "one cocktail for all" to "tailor-made cocktails" that are needed for the efficient saccharification of targeted feed stocks prior to the production of biobased products through the biorefinery concept.
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Affiliation(s)
- Anthi Karnaouri
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Leonidas Matsakas
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Evangelos Topakas
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of TechnologyLuleå, Sweden; Biotechnology Laboratory, Department of Synthesis and Development of Industrial Processes, School of Chemical Engineering, National Technical University of AthensAthens, Greece
| | - Ulrika Rova
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
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22
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Sarris D, Papanikolaou S. Biotechnological production of ethanol: Biochemistry, processes and technologies. Eng Life Sci 2016. [DOI: 10.1002/elsc.201400199] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Dimitris Sarris
- Laboratory of Food Microbiology and Biotechnology Department of Food Science and Human Nutrition, Agricultural University of Athens Athens Greece
| | - Seraphim Papanikolaou
- Laboratory of Food Microbiology and Biotechnology Department of Food Science and Human Nutrition, Agricultural University of Athens Athens Greece
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Koradiya M, Duggirala S, Tipre D, Dave S. Pretreatment optimization of Sorghum pioneer biomass for bioethanol production and its scale-up. BIORESOURCE TECHNOLOGY 2016; 199:142-147. [PMID: 26384087 DOI: 10.1016/j.biortech.2015.08.156] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/29/2015] [Accepted: 08/31/2015] [Indexed: 06/05/2023]
Abstract
Based on one parameter at a time, saccharification of delignified sorghum biomass by 4% and 70% v/v sulfuric acid resulted in maximum 30.8 and 33.8 g% sugar production from biomass respectively. The Box Behnken Design was applied for further optimization of acid hydrolysis. As a result of the designed experiment 36.3g% sugar production was achieved when 3% v/v H2SO4 treatment given for 60 min at 180°C. The process was scaled-up to treat 2 kg of biomass. During the screening of yeast cultures, isolate C, MK-I and N were found to be potent ethanol producers from sorghum hydrolyzate. Culture MK-I was the best so used for scale up of ethanol production up to 25 L capacity, which gave a yield of 0.49 g ethanol/g sugar from hydrolyzate obtained from 2 kg of sorghum biomass.
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Affiliation(s)
- Manoj Koradiya
- Department of Microbiology, Biogas Research Centre, Gujarat Vidhyapith, Sadra 382424, Gujarat, India
| | - Srinivas Duggirala
- Department of Microbiology, Biogas Research Centre, Gujarat Vidhyapith, Sadra 382424, Gujarat, India
| | - Devayani Tipre
- Department of Microbiology and Biotechnology, School of Sciences, Gujarat University, Ahmedabad 380 009, Gujarat, India
| | - Shailesh Dave
- Department of Microbiology and Biotechnology, School of Sciences, Gujarat University, Ahmedabad 380 009, Gujarat, India.
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Matsakas L, Rova U, Christakopoulos P. Sequential parametric optimization of methane production from different sources of forest raw material. Front Microbiol 2015; 6:1163. [PMID: 26539186 PMCID: PMC4611140 DOI: 10.3389/fmicb.2015.01163] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 10/06/2015] [Indexed: 11/13/2022] Open
Abstract
The increase in environmental problems and the shortage of fossil fuels have led to the need for action in the development of sustainable and renewable fuels. Methane is produced through anaerobic digestion of organic materials and is a biofuel with very promising characteristics. The success in using methane as a biofuel has resulted in the operation of several commercial-scale plants and the need to exploit novel materials to be used. Forest biomass can serve as an excellent candidate for use as raw material for anaerobic digestion. During this work, both hardwood and softwood species-which are representative of the forests of Sweden-were used for the production of methane. Initially, when untreated forest materials were used for the anaerobic digestion, the yields obtained were very low, even with the addition of enzymes, reaching a maximum of only 40 mL CH4/g VS when birch was used. When hydrothermal pretreatment was applied, the enzymatic digestibility improved up to 6.7 times relative to that without pretreatment, and the yield of methane reached up to 254 mL CH4/g VS. Then the effect of chemical/enzymatic detoxification was examined, where laccase treatment improved the methane yield from the more harshly pretreated materials while it had no effect on the more mildly pretreated material. Finally, addition of cellulolytic enzymes during the digestion improved the methane yields from spruce and pine, whereas for birch separate saccharification was more beneficial. To achieve high yields in spruce 30 filter paper units (FPU)/g was necessary, whereas 15 FPU/g was enough when pine and birch were used. During this work, the highest methane yields obtained from pine and birch were 179.9 mL CH4/g VS and 304.8 mL CH4/g VS, respectively. For mildly and severely pretreated spruce, the methane yields reached 259.4 mL CH4/g VS and 276.3 mL CH4/g VS, respectively. We have shown that forest material can serve as raw material for efficient production of methane. The initially low yields from the untreated materials were significantly improved by the introduction of a hydrothermal pretreatment. Moreover, enzymatic detoxification was beneficial, but mainly for severely pretreated materials. Finally, enzymatic saccharification increased the methane yields even further.
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Affiliation(s)
- Leonidas Matsakas
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology Luleå, Sweden
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Kawaguchi H, Teramura H, Uematsu K, Hara KY, Hasunuma T, Hirano K, Sazuka T, Kitano H, Tsuge Y, Kahar P, Niimi-Nakamura S, Oinuma KI, Takaya N, Kasuga S, Ogino C, Kondo A. Phenyllactic acid production by simultaneous saccharification and fermentation of pretreated sorghum bagasse. BIORESOURCE TECHNOLOGY 2015; 182:169-178. [PMID: 25689311 DOI: 10.1016/j.biortech.2015.01.097] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 01/22/2015] [Accepted: 01/23/2015] [Indexed: 06/04/2023]
Abstract
Dilute acid-pretreated sorghum bagasse, which was predominantly composed of glucan (59%) and xylose (7.2%), was used as a lignocellulosic feedstock for d-phenyllactic acid (PhLA) production by a recombinant Escherichia coli strain expressing phenylpyruvate reductase from Wickerhamia fluorescens. During fermentation with enzymatic hydrolysate of sorghum bagasse as a carbon source, the PhLA yield was reduced by 35% compared to filter paper hydrolysate, and metabolomics analysis revealed that NAD(P)H regeneration and intracellular levels of erythrose-4-phosphate and phosphoenolpyruvate for PhLA biosynthesis markedly reduced. Compared to separate hydrolysis and fermentation (SHF) with sorghum bagasse hydrolysate, simultaneous saccharification and fermentation (SSF) of sorghum bagasse under glucose limitation conditions yielded 4.8-fold more PhLA with less accumulation of eluted components, including p-coumaric acid and aldehydes, which inhibited PhLA fermentation. These results suggest that gradual enzymatic hydrolysis during SSF enhances PhLA production under glucose limitation and reduces the accumulation of fermentation inhibitors, collectively leading to increased PhLA yield.
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Affiliation(s)
- Hideo Kawaguchi
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe 657-8501, Japan
| | - Hiroshi Teramura
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe 657-8501, Japan
| | - Kouji Uematsu
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe 657-8501, Japan
| | - Kiyotaka Y Hara
- Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan
| | - Tomohisa Hasunuma
- Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan
| | - Ko Hirano
- Bioscience and Biotechnology Center, Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan
| | - Takashi Sazuka
- Bioscience and Biotechnology Center, Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan
| | - Hidemi Kitano
- Bioscience and Biotechnology Center, Nagoya University, Furo, Chikusa, Nagoya 464-8601, Japan
| | - Yota Tsuge
- Organization of Advanced Science and Technology, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan
| | - Prihardi Kahar
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe 657-8501, Japan
| | - Satoko Niimi-Nakamura
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe 657-8501, Japan
| | - Ken-Ichi Oinuma
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
| | - Naoki Takaya
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan
| | - Shigemitsu Kasuga
- Education and Research Center of Alpine Field Science, Faculty of Agriculture, Shinshu University, Minamiminowa, Nagano 399-4598, Japan
| | - Chiaki Ogino
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe 657-8501, Japan
| | - Akihiko Kondo
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe 657-8501, Japan; RIKEN Center for Sustainable Resource Science, 1-7-22 Suehirocho, Turumi-ku, Yokohama, Kanagawa 230-0045, Japan.
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Paschos T, Xiros C, Christakopoulos P. Ethanol effect on metabolic activity of the ethalogenic fungus Fusarium oxysporum. BMC Biotechnol 2015; 15:15. [PMID: 25887038 PMCID: PMC4417268 DOI: 10.1186/s12896-015-0130-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 02/24/2015] [Indexed: 11/25/2022] Open
Abstract
Background Fusarium oxysporum is a filamentous fungus which has attracted a lot of scientific interest not only due to its ability to produce a variety of lignocellulolytic enzymes, but also because it is able to ferment both hexoses and pentoses to ethanol. Although this fungus has been studied a lot as a cell factory, regarding applications for the production of bioethanol and other high added value products, no systematic study has been performed concerning its ethanol tolerance levels. Results In aerobic conditions it was shown that both the biomass production and the specific growth rate were affected by the presence of ethanol. The maximum allowable ethanol concentration, above which cells could not grow, was predicted to be 72 g/L. Under limited aeration conditions the ethanol-producing capability of the cells was completely inhibited at 50 g/L ethanol. The lignocellulolytic enzymatic activities were affected to a lesser extent by the presence of ethanol, while the ethanol inhibitory effect appears to be more severe at elevated temperatures. Moreover, when the produced ethanol was partially removed from the broth, it led to an increase in fermenting ability of the fungus up to 22.5%. The addition of F. oxysporum’s system was shown to increase the fermentation of pretreated wheat straw by 11%, in co-fermentation with Saccharomyces cerevisiae. Conclusions The assessment of ethanol tolerance levels of F. oxysporum on aerobic growth, on lignocellulolytic activities and on fermentative performance confirmed its biotechnological potential for the production of bioethanol. The cellulolytic and xylanolytic enzymes of this fungus could be exploited within the biorefinery concept as their ethanol resistance is similar to that of the commercial enzymes broadly used in large scale fermentations and therefore, may substantially contribute to a rational design of a bioconversion process involving F. oxysporum. The SSCF experiments on liquefied wheat straw rich in hemicellulose indicated that the contribution of the metabolic system of F. oxysporum in a co-fermentation with S. cerevisiae may play a secondary role.
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Affiliation(s)
- Thomas Paschos
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Str, Zografou Campus, Athens, 5780, Greece.
| | - Charilaos Xiros
- Industrial Biotechnology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, Gothenburg, 41296, Sweden.
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, SE-971 87, Sweden.
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Ethanol Production from Enzymatically Treated Dried Food Waste Using Enzymes Produced On-Site. SUSTAINABILITY 2015. [DOI: 10.3390/su7021446] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Matsakas L, Bonturi N, Miranda EA, Rova U, Christakopoulos P. High concentrations of dried sorghum stalks as a biomass feedstock for single cell oil production by Rhodosporidium toruloides. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:6. [PMID: 25632300 PMCID: PMC4308834 DOI: 10.1186/s13068-014-0190-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Accepted: 12/18/2014] [Indexed: 05/08/2023]
Abstract
BACKGROUND Environmental crisis and concerns for energy security have made the research for renewable fuels that will substitute the usage of fossil fuels an important priority. Biodiesel is a potential substitute for petroleum, but its feasibility is hindered by the utilization of edible vegetable oil as raw material, which is responsible for a large fraction of the production cost and fosters the food versus fuel competition. Microbial oils are an interesting alternative as they do not compete with food production, and low cost renewable materials could serve as raw materials during cultivation of microorganisms. Sweet sorghum is an excellent candidate as substrate for microbial oil production, as it possesses high photosynthetic activity yielding high amounts of soluble and insoluble carbohydrates, and does not require high fertilization and irrigation rates. RESULTS Initially the ability of sweet sorghum to fully support yeast growth, both as a carbon and nitrogen source was evaluated. It was found that addition of an external nitrogen source had a negative impact on single cell oil (SCO) production yields, which has a positive effect on the process economics. Subsequently the effect of the presence of a distinct saccharification step on SCO was examined. The presence of an enzymatic saccharification step prior to SCO production improved the production of SCO, especially in high solid concentrations. Removal of solids was also investigated and its positive effect on SCO production was also demonstrated. When juice from 20% w/w enzymatically liquefied sweet sorghum was used as the raw material, SCO production was 13.77 g/L. To the best of our knowledge this is one of the highest SCO titers reported in the literature when renewable raw materials were utilized. CONCLUSIONS The use of sweet sorghum at high solid concentrations as a feedstock for the efficient production of SCO by Rhodosporidium toruloides was demonstrated. Moreover, addition of enzymes not only led to liquefaction of sweet sorghum and permitted liquid fermentation, but also enhanced lipid production by 85.1% and 15.9% when dried stalks or stalk juice was used, respectively.
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Affiliation(s)
- Leonidas Matsakas
- />Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden
| | - Nemailla Bonturi
- />Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden
- />Department of Materials and Bioprocess Engineering, School of Chemical Engineering, State University of Campinas, Av. Albert Einstein, 500, 13083-852 Campinas, SP Brazil
| | - Everson Alves Miranda
- />Department of Materials and Bioprocess Engineering, School of Chemical Engineering, State University of Campinas, Av. Albert Einstein, 500, 13083-852 Campinas, SP Brazil
| | - Ulrika Rova
- />Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden
| | - Paul Christakopoulos
- />Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, SE-971 87 Luleå, Sweden
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Qureshi AS, Zhang J, Bao J. High ethanol fermentation performance of the dry dilute acid pretreated corn stover by an evolutionarily adapted Saccharomyces cerevisiae strain. BIORESOURCE TECHNOLOGY 2015; 189:399-404. [PMID: 25930238 DOI: 10.1016/j.biortech.2015.04.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 04/08/2015] [Accepted: 04/09/2015] [Indexed: 05/15/2023]
Abstract
Ethanol fermentation was investigated at the high solids content of the dry dilute sulfuric acid pretreated corn stover feedstock using an evolutionary adapted Saccharomyces cerevisiae DQ1 strain. The evolutionary adaptation was conducted by successively transferring the S. cerevisiae DQ1 cells into the inhibitors containing corn stover hydrolysate every 12h and finally a stable yeast strain was obtained after 65 days' continuous adaptation. The ethanol fermentation performance using the adapted strain was significantly improved with the high ethanol titer of 71.40 g/L and the high yield of 80.34% in the simultaneous saccharification and fermentation (SSF) at 30% solids content. No wastewater was generated from pretreatment to fermentation steps. The results were compared with the published cellulosic ethanol fermentation cases, and the obvious advantages of the present work were demonstrated not only at the high ethanol titer and yield, but also the significant reduction of wastewater generation and potential cost reduction.
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Affiliation(s)
- Abdul Sattar Qureshi
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Jian Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Jie Bao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
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Evaluation of dried sweet sorghum stalks as raw material for methane production. BIOMED RESEARCH INTERNATIONAL 2014; 2014:731731. [PMID: 25210715 PMCID: PMC4153003 DOI: 10.1155/2014/731731] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Revised: 07/17/2014] [Accepted: 07/23/2014] [Indexed: 11/20/2022]
Abstract
The potential of utilizing dried sweet sorghum stalks as raw material for anaerobic digestion has been evaluated. Two different treatments were tested, a mild thermal and an enzymatic, alone or in combination. Thermal pretreatment was found to decrease the methane yields, whereas one-step enzymatic treatment resulted in a significant increase of 15.1% comparing to the untreated sweet sorghum. Subsequently, in order to increase the total methane production, the combined effect of enzyme load and I/S on methane yields from sweet sorghum was evaluated by employing response surface methodology. The obtained model showed that the maximum methane yield that could be achieved is 296 mL CH4/g VS at I/S ratio of 0.35 with the addition of 11.12 FPU/g sweet sorghum.
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Li M, Feng S, Wu L, Li Y, Fan C, Zhang R, Zou W, Tu Y, Jing HC, Li S, Peng L. Sugar-rich sweet sorghum is distinctively affected by wall polymer features for biomass digestibility and ethanol fermentation in bagasse. BIORESOURCE TECHNOLOGY 2014; 167:14-23. [PMID: 24968107 DOI: 10.1016/j.biortech.2014.04.086] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Revised: 04/23/2014] [Accepted: 04/26/2014] [Indexed: 05/05/2023]
Abstract
Sweet sorghum has been regarded as a typical species for rich soluble-sugar and high lignocellulose residues, but their effects on biomass digestibility remain unclear. In this study, we examined total 63 representative sweet sorghum accessions that displayed a varied sugar level at stalk and diverse cell wall composition at bagasse. Correlative analysis showed that both soluble-sugar and dry-bagasse could not significantly affect lignocellulose saccharification under chemical pretreatments. Comparative analyses of five typical pairs of samples indicated that DP of crystalline cellulose and arabinose substitution degree of non-KOH-extractable hemicelluloses distinctively affected lignocellulose crystallinity for high biomass digestibility. By comparison, lignin could not alter lignocellulose crystallinity, but the KOH-extractable G-monomer predominately determined lignin negative impacts on biomass digestions, and the G-levels released from pretreatments significantly inhibited yeast fermentation. The results also suggested potential genetic approaches for enhancing soluble-sugar level and lignocellulose digestibility and reducing ethanol conversion inhibition in sweet sorghum.
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Affiliation(s)
- Meng Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Shengqiu Feng
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Leiming Wu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Ying Li
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Chunfen Fan
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Rui Zhang
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Weihua Zou
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Yuanyuan Tu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Hai-Chun Jing
- Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Shizhong Li
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
| | - Liangcai Peng
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Biomass and Bioenergy Research Centre, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
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Lin J, Li S, Sun M, Zhang C, Yang W, Zhang Z, Li X, Li S. Microbial lipid production by oleaginous yeast ind-xylose solution using a two-stage culture mode. RSC Adv 2014. [DOI: 10.1039/c4ra01453g] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Optimization of Ethanol Production from NaOH-Pretreated Solid State Fermented Sweet Sorghum Bagasse. ENERGIES 2014. [DOI: 10.3390/en7074054] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Matsakas L, Kekos D, Loizidou M, Christakopoulos P. Utilization of household food waste for the production of ethanol at high dry material content. BIOTECHNOLOGY FOR BIOFUELS 2014; 7:4. [PMID: 24401142 PMCID: PMC3892076 DOI: 10.1186/1754-6834-7-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Accepted: 12/24/2013] [Indexed: 05/15/2023]
Abstract
BACKGROUND Environmental issues and shortage of fossil fuels have turned the public interest to the utilization of renewable, environmentally friendly fuels, such as ethanol. In order to minimize the competition between fuels and food production, researchers are focusing their efforts to the utilization of wastes and by-products as raw materials for the production of ethanol. household food wastes are being produced in great quantities in European Union and their handling can be a challenge. Moreover, their disposal can cause severe environmental issues (for example emission of greenhouse gasses). On the other hand, they contain significant amounts of sugars (both soluble and insoluble) and they can be used as raw material for the production of ethanol. RESULTS Household food wastes were utilized as raw material for the production of ethanol at high dry material consistencies. A distinct liquefaction/saccharification step has been included to the process, which rapidly reduced the viscosity of the high solid content substrate, resulting in better mixing of the fermenting microorganism. This step had a positive effect in both ethanol production and productivity, leading to a significant increase in both values, which was up to 40.81% and 4.46 fold, respectively. Remaining solids (residue) after fermentation at 45% w/v dry material (which contained also the unhydrolyzed fraction of cellulose), were subjected to a hydrothermal pretreatment in order to be utilized as raw material for a subsequent ethanol fermentation. This led to an increase of 13.16% in the ethanol production levels achieving a final ethanol yield of 107.58 g/kg dry material. CONCLUSIONS In conclusion, the ability of utilizing household food waste for the production of ethanol at elevated dry material content has been demonstrated. A separate liquefaction/saccharification process can increase both ethanol production and productivity. Finally, subsequent fermentation of the remaining solids could lead to an increase of the overall ethanol production yield.
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Affiliation(s)
- Leonidas Matsakas
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 5 Iroon Polytechniou Str, Zografou Campus, 15780 Athens, Greece
- Department of Civil, Biochemical and Chemical Process Engineering, Division of Sustainable Process Engineering, Environmental and Natural Resources Engineering, Luleå University of Technology, SE 971 87 Luleå, Sweden
| | - Dimitris Kekos
- Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, 5 Iroon Polytechniou Str, Zografou Campus, 15780 Athens, Greece
| | - Maria Loizidou
- Unit of Environmental Science and Technology, School of Chemical Engineering, National Technical University of Athens, 5, Iroon Polytechniou Str, Zografou Campus, 15780 Athens, Greece
| | - Paul Christakopoulos
- Department of Civil, Biochemical and Chemical Process Engineering, Division of Sustainable Process Engineering, Environmental and Natural Resources Engineering, Luleå University of Technology, SE 971 87 Luleå, Sweden
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Koppram R, Tomás-Pejó E, Xiros C, Olsson L. Lignocellulosic ethanol production at high-gravity: challenges and perspectives. Trends Biotechnol 2014; 32:46-53. [DOI: 10.1016/j.tibtech.2013.10.003] [Citation(s) in RCA: 253] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 10/07/2013] [Accepted: 10/10/2013] [Indexed: 11/30/2022]
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ElMekawy A, Diels L, De Wever H, Pant D. Valorization of cereal based biorefinery byproducts: reality and expectations. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:9014-27. [PMID: 23931701 PMCID: PMC3774676 DOI: 10.1021/es402395g] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The growth of the biobased economy will lead to an increase in new biorefinery activities. All biorefineries face the regular challenges of efficiently and economically treating their effluent to be compatible with local discharge requirements and to minimize net water consumption. The amount of wastes resulting from biorefineries industry is exponentially growing. The valorization of such wastes has drawn considerable attention with respect to resources with an observable economic and environmental concern. This has been a promising field which shows great prospective toward byproduct usage and increasing value obtained from the biorefinery. However, full-scale realization of biorefinery wastes valorization is not straightforward because several microbiological, technological and economic challenges need to be resolved. In this review we considered valorization options for cereals based biorefineries wastes while identifying their challenges and exploring the opportunities for future process.
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Affiliation(s)
- Ahmed ElMekawy
- Separation
and Conversion Technologies, VITO-Flemish Institute for
Technological Research,
Boeretang 200, 2400 Mol, Belgium
- Genetic Engineering and Biotechnology
Research Institute, Minufiya University, Sadat City, Egypt
| | - Ludo Diels
- Separation
and Conversion Technologies, VITO-Flemish Institute for
Technological Research,
Boeretang 200, 2400 Mol, Belgium
| | - Heleen De Wever
- Separation
and Conversion Technologies, VITO-Flemish Institute for
Technological Research,
Boeretang 200, 2400 Mol, Belgium
| | - Deepak Pant
- Separation
and Conversion Technologies, VITO-Flemish Institute for
Technological Research,
Boeretang 200, 2400 Mol, Belgium
- Phone: +32 14336969; fax: +32 14326586; e-mail: ;
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Heredia-Olea E, Pérez-Carrillo E, Serna-Saldívar SO. Production of ethanol from sweet sorghum bagasse pretreated with different chemical and physical processes and saccharified with fiber degrading enzymes. BIORESOURCE TECHNOLOGY 2013; 134:386-90. [PMID: 23489562 DOI: 10.1016/j.biortech.2013.01.162] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 01/28/2013] [Accepted: 01/29/2013] [Indexed: 05/15/2023]
Abstract
The C5 and C6 sugars generated from sweet sorghum bagasse pretreated with five different chemical or physical schemes and then further hydrolyzed with a fibrolytic cocktail were determined. Hydrolysates were fermented with three yeast strains in order to determine which combination generated the highest amount of bioethanol. The bagasse only treated with the enzyme complex generated 50% of the total C5 and C6 sugars available. The pressure-cooked and extruded pretreatments further hydrolyzed with the enzymes generated 17% more sugars compared to the enzyme alone treatment. The enzyme increased the total sugar content in approximately 40% in the three acid pretreated hydrolysates. Among the different pretreatments, only the extrusion process did not generate inhibitors acetic acid, furfural and 5-hydroxymethylfurfural. At 24 h fermentation, the strains Saccharomyces cerevisiae and Issatchenkia orientalis produced, respectively 183.9 and 209.2 mg ethanol/g dry bagasse previously treated with HCl and enzymes.
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Affiliation(s)
- Erick Heredia-Olea
- Centro de Biotecnología-FEMSA, Tecnológico de Monterrey, Av., Eugenio Garza Sada 2501 Sur, CP 64849, Monterrey, NL, Mexico
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Petrik S, Kádár Z, Márová I. Utilization of hydrothermally pretreated wheat straw for production of bioethanol and carotene-enriched biomass. BIORESOURCE TECHNOLOGY 2013; 133:370-377. [PMID: 23434815 DOI: 10.1016/j.biortech.2013.01.151] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 01/27/2013] [Accepted: 01/29/2013] [Indexed: 06/01/2023]
Abstract
In this work hydrothermally pretreated wheat straw was used for production of bioethanol by Saccharomyces cerevisiae and carotene-enriched biomass by red yeasts Rhodotorula glutinis, Cystofilobasidium capitatum and Sporobolomyces roseus. To evaluate the convertibility of pretreated wheat straw into ethanol, simultaneous saccharification and fermentation of S. cerevisiae was performed under semi-anaerobic conditions. The highest ethanol production efficiency of 65-66% was obtained following pretreatment at 200°C without the catalytic action of acetic acid, and at 195 and 200°C respectively in the presence of catalyst. Red yeast strain S. roseus produced 1.73-2.22 mg g(-1) of ergosterol on the filter cake, 1.15-4.17 mg g(-1) of ergosterol and 1.23-1.56 mg g(-1) of β-carotene on pretreated wheat straw hydrolysates and also the highest amount of carotenoids and ergosterol on untreated wheat straw (1.70 and 4.17 mg g(-1), respectively).
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Affiliation(s)
- Siniša Petrik
- Materials Research Centre, Faculty of Chemistry, Brno University of Technology, Brno, Czech Republic.
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