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Liu C, Choi B, Efimova E, Nygård Y, Santala S. Enhanced upgrading of lignocellulosic substrates by coculture of Saccharomyces cerevisiae and Acinetobacter baylyi ADP1. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2024; 17:61. [PMID: 38711153 DOI: 10.1186/s13068-024-02510-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 04/23/2024] [Indexed: 05/08/2024]
Abstract
BACKGROUND Lignocellulosic biomass as feedstock has a huge potential for biochemical production. Still, efficient utilization of hydrolysates derived from lignocellulose is challenged by their complex and heterogeneous composition and the presence of inhibitory compounds, such as furan aldehydes. Using microbial consortia where two specialized microbes complement each other could serve as a potential approach to improve the efficiency of lignocellulosic biomass upgrading. RESULTS This study describes the simultaneous inhibitor detoxification and production of lactic acid and wax esters from a synthetic lignocellulosic hydrolysate by a defined coculture of engineered Saccharomyces cerevisiae and Acinetobacter baylyi ADP1. A. baylyi ADP1 showed efficient bioconversion of furan aldehydes present in the hydrolysate, namely furfural and 5-hydroxymethylfurfural, and did not compete for substrates with S. cerevisiae, highlighting its potential as a coculture partner. Furthermore, the remaining carbon sources and byproducts of S. cerevisiae were directed to wax ester production by A. baylyi ADP1. The lactic acid productivity of S. cerevisiae was improved approximately 1.5-fold (to 0.41 ± 0.08 g/L/h) in the coculture with A. baylyi ADP1, compared to a monoculture of S. cerevisiae. CONCLUSION The coculture of yeast and bacterium was shown to improve the consumption of lignocellulosic substrates and the productivity of lactic acid from a synthetic lignocellulosic hydrolysate. The high detoxification capacity and the ability to produce high-value products by A. baylyi ADP1 demonstrates the strain to be a potential candidate for coculture to increase production efficiency and economics of S. cerevisiae fermentations.
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Affiliation(s)
- Changshuo Liu
- Faculty of Engineering and Natural Sciences, Tampere University, Hervanta Campus, Tampere, Finland
| | - Bohyun Choi
- Department of Life Sciences, Industrial Biotechnology, Chalmers University of Technology, Gothenburg, Sweden
| | - Elena Efimova
- Faculty of Engineering and Natural Sciences, Tampere University, Hervanta Campus, Tampere, Finland
| | - Yvonne Nygård
- Department of Life Sciences, Industrial Biotechnology, Chalmers University of Technology, Gothenburg, Sweden
- VTT Technical Research Centre of Finland, Espoo, Finland
| | - Suvi Santala
- Faculty of Engineering and Natural Sciences, Tampere University, Hervanta Campus, Tampere, Finland.
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Sroka P, Tarko T, Duda A. The Impact of Furfural on the Quality of Meads. Molecules 2023; 29:29. [PMID: 38202612 PMCID: PMC10779583 DOI: 10.3390/molecules29010029] [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: 11/17/2023] [Revised: 12/13/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024] Open
Abstract
Furfural is a naturally occurring compound in bee honey, classified as a fermentation inhibitor. The aim of this study was to ascertain the concentration of furfural in mead worts, prepared at room temperature (unsaturated) and heated to boiling for 10 to 70 min (saturated), with an extract of 25 to 45°Brix. Moreover, the impact of the furfural on the fermentation course of mead wort was assessed. For this purpose, fermentation tests were conducted using mead wort (30°Brix) to which furfural was added at concentrations ranging from 1 to 100 mg/L. HS-SPME-GC-TOF-MS analysis revealed that the furfural concentration in mead worts varied between 2.3 and 5.3 mg/L. In saturated worts, the concentration increased by 2.8 to 4.5 times. Acidification of mead wort prior to boiling led to further increase in furfural concentration. The greatest changes occurred in the least concentrated worts, having the lowest buffer capacity. The addition of furfural to the mead wort did not inhibit fermentation, and an increase in attenuation was observed in the samples containing 2 mg/L of furfural compared to the control. Throughout the fermentation most of the furfural was reduced to furfuryl alcohol.
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Affiliation(s)
- Paweł Sroka
- Department of Fermentation Technology and Microbiology, University of Agriculture in Krakow, ul. Balicka 122, 30-149 Kraków, Poland;
| | - Tomasz Tarko
- Department of Fermentation Technology and Microbiology, University of Agriculture in Krakow, ul. Balicka 122, 30-149 Kraków, Poland;
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Jilani SB, Olson DG. Mechanism of furfural toxicity and metabolic strategies to engineer tolerance in microbial strains. Microb Cell Fact 2023; 22:221. [PMID: 37891678 PMCID: PMC10612203 DOI: 10.1186/s12934-023-02223-x] [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: 08/29/2023] [Accepted: 10/05/2023] [Indexed: 10/29/2023] Open
Abstract
Lignocellulosic biomass represents a carbon neutral cheap and versatile source of carbon which can be converted to biofuels. A pretreatment step is frequently used to make the lignocellulosic carbon bioavailable for microbial metabolism. Dilute acid pretreatment at high temperature and pressure is commonly utilized to efficiently solubilize the pentose fraction by hydrolyzing the hemicellulose fibers and the process results in formation of furans-furfural and 5-hydroxymethyl furfural-and other inhibitors which are detrimental to metabolism. The presence of inhibitors in the medium reduce productivity of microbial biocatalysts and result in increased production costs. Furfural is the key furan inhibitor which acts synergistically along with other inhibitors present in the hydrolysate. In this review, the mode of furfural toxicity on microbial metabolism and metabolic strategies to increase tolerance is discussed. Shared cellular targets between furfural and acetic acid are compared followed by discussing further strategies to engineer tolerance. Finally, the possibility to use furfural as a model inhibitor of dilute acid pretreated lignocellulosic hydrolysate is discussed. The furfural tolerant strains will harbor an efficient lignocellulosic carbon to pyruvate conversion mechanism in presence of stressors in the medium. The pyruvate can be channeled to any metabolite of interest by appropriate modulation of downstream pathway of interest. The aim of this review is to emphasize the use of hydrolysate as a carbon source for bioproduction of biofuels and other compounds of industrial importance.
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Affiliation(s)
- S Bilal Jilani
- Thayer School of Engineering, Dartmouth College, 15 Thayer Drive, Hanover, NH, 03755, USA.
| | - Daniel G Olson
- Thayer School of Engineering, Dartmouth College, 15 Thayer Drive, Hanover, NH, 03755, USA
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
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Kumar S, Agyeman-Duah E, Ujor VC. Whole-Genome Sequence and Fermentation Characteristics of Enterobacter hormaechei UW0SKVC1: A Promising Candidate for Detoxification of Lignocellulosic Biomass Hydrolysates and Production of Value-Added Chemicals. Bioengineering (Basel) 2023; 10:1090. [PMID: 37760192 PMCID: PMC10525534 DOI: 10.3390/bioengineering10091090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/11/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
Enterobacter hormaechei is part of the Enterobacter cloacae complex (ECC), which is widespread in nature. It is a facultative Gram-negative bacterium of medical and industrial importance. We assessed the metabolic and genetic repertoires of a new Enterobacter isolate. Here, we report the whole-genome sequence of a furfural- and 5-hydroxymethyl furfural (HMF)-tolerant strain of E. hormaechei (UW0SKVC1), which uses glucose, glycerol, xylose, lactose and arabinose as sole carbon sources. This strain exhibits high tolerance to furfural (IC50 = 34.2 mM; ~3.3 g/L) relative to Escherichia coli DH5α (IC50 = 26.0 mM; ~2.5 g/L). Furfural and HMF are predominantly converted to their less-toxic alcohols. E. hormaechei UW0SKVC1 produces 2,3-butanediol, acetoin, and acetol, among other compounds of industrial importance. E. hormaechei UW0SKVC1 produces as high as ~42 g/L 2,3-butanediol on 60 g/L glucose or lactose. The assembled genome consists of a 4,833,490-bp chromosome, with a GC content of 55.35%. Annotation of the assembled genome revealed 4586 coding sequences and 4516 protein-coding genes (average length 937-bp) involved in central metabolism, energy generation, biodegradation of xenobiotic compounds, production of assorted organic compounds, and drug resistance. E. hormaechei UW0SKVC1 shows considerable promise as a biocatalyst and a genetic repository of genes whose protein products may be harnessed for the efficient bioconversion of lignocellulosic biomass, abundant glycerol and lactose-replete whey permeate to value-added chemicals.
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Affiliation(s)
| | | | - Victor C. Ujor
- Metabolic Engineering and Fermentation Science Group, Department of Food Science, University of Wisconsin-Madison, Babcock Hall, 1605 Linden Drive, Madison, WI 53706, USA; (S.K.); (E.A.-D.)
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Jin T, Xing X, Xie Y, Sun Y, Bian S, Liu L, Chen G, Wang X, Yu X, Su Y. Evaluation of Preparation and Detoxification of Hemicellulose Hydrolysate for Improved Xylitol Production from Quinoa Straw. Int J Mol Sci 2022; 24:516. [PMID: 36613957 PMCID: PMC9820623 DOI: 10.3390/ijms24010516] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/11/2022] [Accepted: 12/21/2022] [Indexed: 12/29/2022] Open
Abstract
Quinoa straw is rich in hemicellulose, and it could be hydrolyzed into xylose. It is a promising energy resource alternative that acts as a potential low-cost material for producing xylitol. In this study, quinoa straw was used as a substrate subjected to the hydrolysis of dilute sulfuric acid solution. Based on the production of xylose and inhibitors during hydrolysis, the optimal conditions for the hydrolysis of hemicellulose in quinoa straw were determined. Detoxification was performed via activated carbon adsorption. The optimal detoxification conditions were determined on the basis of major inhibitor concentrations in the hydrolysate. When the addition of activated carbon was 3% at 30 °C for 40 min, the removal of formic acid, acetic acid, furfural, and 5-HMF could reach 66.52%, 64.54%, 88.31%, and 89.44%, respectively. In addition to activated carbon adsorption, vacuum evaporation was further conducted to perform two-step detoxification. Subsequently, the detoxified hydrolysate was used for xylitol fermentation. The yield of xylitol reached 0.50 g/g after 96 h of fermentation by Candida tropicalis (CICC 1779). It is 1.2-fold higher than that obtained through the sole vacuum evaporation method. This study validated the feasibility of xylitol production from quinoa straw via a biorefinery process.
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Affiliation(s)
- Tingwei Jin
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, The Ministry of Education, Jilin Agricultural University, Changchun 130118, China
| | - Xiwen Xing
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, The Ministry of Education, Jilin Agricultural University, Changchun 130118, China
| | - Yubing Xie
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
| | - Yan Sun
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, The Ministry of Education, Jilin Agricultural University, Changchun 130118, China
| | - Sijia Bian
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, The Ministry of Education, Jilin Agricultural University, Changchun 130118, China
| | - Liying Liu
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, The Ministry of Education, Jilin Agricultural University, Changchun 130118, China
| | - Guang Chen
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, The Ministry of Education, Jilin Agricultural University, Changchun 130118, China
| | - Xinzhe Wang
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, The Ministry of Education, Jilin Agricultural University, Changchun 130118, China
| | - Xiaoxiao Yu
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, The Ministry of Education, Jilin Agricultural University, Changchun 130118, China
| | - Yingjie Su
- College of Life Science, Jilin Agricultural University, Changchun 130118, China
- Key Laboratory of Straw Comprehensive Utilization and Black Soil Conservation, The Ministry of Education, Jilin Agricultural University, Changchun 130118, China
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Straathof AJ. Modelling of end-product inhibition in fermentation. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2022.108796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Ujor VC, Okonkwo CC. Microbial detoxification of lignocellulosic biomass hydrolysates: Biochemical and molecular aspects, challenges, exploits and future perspectives. Front Bioeng Biotechnol 2022; 10:1061667. [PMID: 36483774 PMCID: PMC9723337 DOI: 10.3389/fbioe.2022.1061667] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 10/31/2022] [Indexed: 08/26/2023] Open
Abstract
Valorization of lignocellulosic biomass (LB) has the potential to secure sustainable energy production without impacting food insecurity, whist relieving over reliance on finite fossil fuels. Agro-derived lignocellulosic residues such as wheat straw, switchgrass, rice bran, and miscanthus have gained relevance as feedstocks for the production of biofuels and chemicals. However, the microorganisms employed in fermentative conversion of carbohydrates to fuels and chemicals are unable to efficiently utilize the sugars derived from LB due to co-production of lignocellulose-derived microbial inhibitory compounds (LDMICs) during LB pretreatment. LDMICs impact microbial growth by inhibition of specific enzymes, cause DNA and cell membrane damage, and elicit cellular redox imbalance. Over the past decade, success has been achieved with the removal of LDMICs prior to fermentation. However, LDMICs removal by chemical processes is often accompanied by sugar losses, which negatively impacts the overall production cost. Hence, in situ removal of LDMICs by fermentative organisms during the fermentation process has garnered considerable attention as the "go-to" approach for economical LDMICs detoxification and bio-chemicals production. In situ removal of LDMICs has been pursued by either engineering more robust biocatalysts or isolating novel microbial strains with the inherent capacity to mineralize or detoxify LDMICs to less toxic compounds. While some success has been made along this line, efficient detoxification and robust production of target bio-chemicals in lignocellulosic hydrolysates (LHs) under largely anaerobic fermentative conditions remains a lingering challenge. Consequently, LB remains an underutilized substrate for bio-chemicals production. In this review, the impact of microbial LH detoxification on overall target molecule production is discussed. Further, the biochemical pathways and mechanisms employed for in situ microbial detoxification of furanic LDMICs [e.g., furfural and 5-hydroxymethylfurfural (HMF)] and phenolic LDMICs (e.g., syringaldehyde, p-coumaric acid, 4-hydroxybenzaldehyde, vanillin, and ferulic acid) are discussed. More importantly, metabolic engineering strategies for the development of LDMIC-tolerant and bio-chemicals overproducing strains and processes are highlighted.
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Affiliation(s)
- Victor C. Ujor
- Metabolic Engineering and Fermentation Science Group, Department of Food Science, University of Wisconsin-Madison, Madison, WI, United States
| | - Christopher C. Okonkwo
- Biotechnology Program, College of Science, The Roux Institute, Northeastern University, Portland, ME, United States
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Synergistic effects of inhibitors and osmotic stress during high gravity bioethanol production from steam-exploded lignocellulosic feedstocks. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2022. [DOI: 10.1016/j.bcab.2022.102414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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9
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Glycerol Utilization as a Sole Carbon Source Disrupts the Membrane Architecture and Solventogenesis in Clostridium beijerinckii NCIMB 8052. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8070339] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Efficient bioconversion of abundant waste glycerol to value-added chemicals calls for a wider range of fermentative workhorses that can catabolize glycerol. In this study, we used quantitative gene expression and solvent profiling, qualitative metabolite analysis, and enzyme activity assays to investigate the factors that limit glycerol utilization as a sole carbon source by Clostridium beijerinckii NCIMB 8052. C. beijerinckii NCIMB 8052 did not produce acetate, acetone and butanol on glycerol. Congruently, the genes encoding the coenzyme A transferase subunits (ctfAB) and bifunctional acetaldehyde-CoA/alcohol dehydrogenase (adhE) were down-regulated up to 135- and 21-fold, respectively, at 12 h in glycerol-grown cells compared to glucose-grown cells. Conversely, NADH-dependent butanol dehydrogenase A (bdhA) was upregulated 2-fold. Glycerol dehydrogenase (gldA) and dihydroxyacetone kinase (subunit dhaK) were upregulated up to 5- and 881-fold, respectively. Glyceraldehyde-3-phosphate dehydrogenase (gapdh) showed mostly similar expression profiles at 12 h on glucose and glycerol. At 24 h, gapdh was downregulated 1.5-fold, while NADP+-dependent gapdh was upregulated up to 1.9-fold. Glycerol-grown cells showed higher or similar activity profiles for all solventogenic enzymes studied, compared to glucose-grown cells. Butyraldehyde (3 g/L) supplementation led to the production of ~0.1 g/L butanol, whilst butyrate (3.5 g/L) supplementation produced 0.7 and 0.5 g/L acetone and butanol, respectively, with glycerol. Further, the long chain saturated fatty acids cyclopentaneundecanoic acid, methyl ester and hexadecanoic acid, butyl ester were detected in glucose- but not in glycerol-grown cells. Collectively, growth on glycerol appears to disrupt synthesis of saturated long chain fatty acids, as well as solventogenesis in C. beijerinckii NCIMB 8052.
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Cagnin L, Gronchi N, Basaglia M, Favaro L, Casella S. Selection of Superior Yeast Strains for the Fermentation of Lignocellulosic Steam-Exploded Residues. Front Microbiol 2021; 12:756032. [PMID: 34803979 PMCID: PMC8601721 DOI: 10.3389/fmicb.2021.756032] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 10/06/2021] [Indexed: 11/13/2022] Open
Abstract
The production of lignocellulosic ethanol calls for a robust fermentative yeast able to tolerate a wide range of toxic molecules that occur in the pre-treated lignocellulose. The concentration of inhibitors varies according to the composition of the lignocellulosic material and the harshness of the pre-treatment used. It follows that the versatility of the yeast should be considered when selecting a robust strain. This work aimed at the validation of seven natural Saccharomyces cerevisiae strains, previously selected for their industrial fitness, for their application in the production of lignocellulosic bioethanol. Their inhibitor resistance and fermentative performances were compared to those of the benchmark industrial yeast S. cerevisiae Ethanol Red, currently utilized in the second-generation ethanol plants. The yeast strains were characterized for their tolerance using a synthetic inhibitor mixture formulated with increasing concentrations of weak acids and furans, as well as steam-exploded lignocellulosic pre-hydrolysates, generally containing the same inhibitors. The eight non-diluted liquors have been adopted to assess yeast ability to withstand bioethanol industrial conditions. The most tolerant S. cerevisiae Fm17 strain, together with the reference Ethanol Red, was evaluated for fermentative performances in two pre-hydrolysates obtained from cardoon and common reed, chosen for their large inhibitor concentrations. S. cerevisiae Fm17 outperformed the industrial strain Ethanol Red, producing up to 18 and 39 g/L ethanol from cardoon and common reed, respectively, with ethanol yields always higher than those of the benchmark strain. This natural strain exhibits great potential to be used as superior yeast in the lignocellulosic ethanol plants.
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Affiliation(s)
- Lorenzo Cagnin
- Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), University of Padova, Legnaro, Italy
| | - Nicoletta Gronchi
- Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), University of Padova, Legnaro, Italy
| | - Marina Basaglia
- Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), University of Padova, Legnaro, Italy
| | - Lorenzo Favaro
- Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), University of Padova, Legnaro, Italy
| | - Sergio Casella
- Department of Agronomy, Food, Natural Resources, Animals and Environment (DAFNAE), University of Padova, Legnaro, Italy
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Gil A. Current insights into lignocellulose related waste valorization. CHEMICAL ENGINEERING JOURNAL ADVANCES 2021. [DOI: 10.1016/j.ceja.2021.100186] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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Vanmarcke G, Deparis Q, Vanthienen W, Peetermans A, Foulquié-Moreno MR, Thevelein JM. A novel AST2 mutation generated upon whole-genome transformation of Saccharomyces cerevisiae confers high tolerance to 5-Hydroxymethylfurfural (HMF) and other inhibitors. PLoS Genet 2021; 17:e1009826. [PMID: 34624020 PMCID: PMC8500407 DOI: 10.1371/journal.pgen.1009826] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/14/2021] [Indexed: 11/19/2022] Open
Abstract
Development of cell factories for conversion of lignocellulosic biomass hydrolysates into biofuels or bio-based chemicals faces major challenges, including the presence of inhibitory chemicals derived from biomass hydrolysis or pretreatment. Extensive screening of 2526 Saccharomyces cerevisiae strains and 17 non-conventional yeast species identified a Candida glabrata strain as the most 5-hydroxymethylfurfural (HMF) tolerant. Whole-genome (WG) transformation of the second-generation industrial S. cerevisiae strain MD4 with genomic DNA from C. glabrata, but not from non-tolerant strains, allowed selection of stable transformants in the presence of HMF. Transformant GVM0 showed the highest HMF tolerance for growth on plates and in small-scale fermentations. Comparison of the WG sequence of MD4 and GVM1, a diploid segregant of GVM0 with similarly high HMF tolerance, surprisingly revealed only nine non-synonymous SNPs, of which none were present in the C. glabrata genome. Reciprocal hemizygosity analysis in diploid strain GVM1 revealed AST2N406I as the only causative mutation. This novel SNP improved tolerance to HMF, furfural and other inhibitors, when introduced in different yeast genetic backgrounds and both in synthetic media and lignocellulose hydrolysates. It stimulated disappearance of HMF and furfural from the medium and enhanced in vitro furfural NADH-dependent reducing activity. The corresponding mutation present in AST1 (i.e. AST1D405I) the paralog gene of AST2, also improved inhibitor tolerance but only in combination with AST2N406I and in presence of high inhibitor concentrations. Our work provides a powerful genetic tool to improve yeast inhibitor tolerance in lignocellulosic biomass hydrolysates and other inhibitor-rich industrial media, and it has revealed for the first time a clear function for Ast2 and Ast1 in inhibitor tolerance.
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Affiliation(s)
- Gert Vanmarcke
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
- Center for Microbiology, VIB, Leuven-Heverlee, Belgium
| | - Quinten Deparis
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
- Center for Microbiology, VIB, Leuven-Heverlee, Belgium
| | - Ward Vanthienen
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
- Center for Microbiology, VIB, Leuven-Heverlee, Belgium
| | - Arne Peetermans
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
- Center for Microbiology, VIB, Leuven-Heverlee, Belgium
| | - Maria R. Foulquié-Moreno
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
- Center for Microbiology, VIB, Leuven-Heverlee, Belgium
| | - Johan M. Thevelein
- Laboratory of Molecular Cell Biology, Institute of Botany and Microbiology, KU Leuven, Leuven-Heverlee, Belgium
- Center for Microbiology, VIB, Leuven-Heverlee, Belgium
- NovelYeast bv, Open Bio-Incubator, Erasmus High School, Brussels (Jette), Belgium
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Ivančić Šantek M, Grubišić M, Galić Perečinec M, Beluhan S, Šantek B. Lipid production by Mortierella isabellina from pretreated corn cobs and effect of lignocellulose derived inhibitors on growth and lipid synthesis. Process Biochem 2021. [DOI: 10.1016/j.procbio.2021.06.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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14
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Colonges K, Jimenez JC, Saltos A, Seguine E, Loor Solorzano RG, Fouet O, Argout X, Assemat S, Davrieux F, Cros E, Boulanger R, Lanaud C. Two Main Biosynthesis Pathways Involved in the Synthesis of the Floral Aroma of the Nacional Cocoa Variety. FRONTIERS IN PLANT SCIENCE 2021; 12:681979. [PMID: 34630447 PMCID: PMC8498224 DOI: 10.3389/fpls.2021.681979] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 08/30/2021] [Indexed: 06/13/2023]
Abstract
Theobroma cacao is the only source that allows the production of chocolate. It is of major economic importance for producing countries such as Ecuador, which is the third-largest cocoa producer in the world. Cocoa is classified into two groups: bulk cocoa and aromatic fine flavour cocoa. In contrast to bulk cocoa, fine flavour cocoa is characterised by fruity and floral notes. One of the characteristics of Nacional cocoa, the emblematic cocoa of Ecuador, is its aromatic ARRIBA flavour. This aroma is mainly composed of floral notes whose genetic and biochemical origin is not well-known. This research objective is to study the genetic and biochemical determinism of the floral aroma of modern Nacional cocoa variety from Ecuador. Genome-Wide Association Study (GWAS) was conducted on a population of 152 genotypes of cocoa trees belonging to the population variety of modern Nacional. Genome-Wide Association Study was conducted by combining SSR and SNP genotyping, assaying biochemical compounds (in roasted and unroasted beans), and sensory evaluations from various tastings. This analysis highlighted different areas of association for all types of traits. In a second step, a search for candidate genes in these association zones was undertaken, which made it possible to find genes potentially involved in the biosynthesis pathway of the biochemical compound identified in associations. Our results show that two biosynthesis pathways seem to be mainly related to the floral note of Nacional cocoa: the monoterpene biosynthesis pathway and the L-phenylalanine degradation pathway. As already suggested, the genetic background would therefore appear as largely explaining the floral note of cocoa.
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Affiliation(s)
- Kelly Colonges
- Cirad, UMR Amélioration Génétique et Adaptation des Plantes Méditerranéennes et Tropicales, Montpellier, France
- Amélioration Génétique et Adaptation des Plantes Méditerranéennes et Tropicales, Univ Montpellier, Cirad, INRAE, Institut Agro, Montpellier, France
- Cirad, UMR Qualisud, Montpellier, France
- Qualisud, Univ Montpellier, Avignon Université, Cirad, Institut Agro, IRD, Université de La Réunion, Montpellier, France
| | - Juan-Carlos Jimenez
- Cocoa and Coffee Research Program, Instituto Nacional de Investigacion Agropecurias, Quito, Ecuador
| | - Alejandra Saltos
- Cocoa and Coffee Research Program, Instituto Nacional de Investigacion Agropecurias, Quito, Ecuador
| | | | | | - Olivier Fouet
- Cirad, UMR Amélioration Génétique et Adaptation des Plantes Méditerranéennes et Tropicales, Montpellier, France
- Amélioration Génétique et Adaptation des Plantes Méditerranéennes et Tropicales, Univ Montpellier, Cirad, INRAE, Institut Agro, Montpellier, France
| | - Xavier Argout
- Cirad, UMR Amélioration Génétique et Adaptation des Plantes Méditerranéennes et Tropicales, Montpellier, France
- Amélioration Génétique et Adaptation des Plantes Méditerranéennes et Tropicales, Univ Montpellier, Cirad, INRAE, Institut Agro, Montpellier, France
| | - Sophie Assemat
- Cirad, UMR Qualisud, Montpellier, France
- Qualisud, Univ Montpellier, Avignon Université, Cirad, Institut Agro, IRD, Université de La Réunion, Montpellier, France
| | - Fabrice Davrieux
- Cirad, UMR Qualisud, Montpellier, France
- Qualisud, Univ Montpellier, Avignon Université, Cirad, Institut Agro, IRD, Université de La Réunion, Montpellier, France
| | - Emile Cros
- Cirad, UMR Qualisud, Montpellier, France
- Qualisud, Univ Montpellier, Avignon Université, Cirad, Institut Agro, IRD, Université de La Réunion, Montpellier, France
| | - Renaud Boulanger
- Cirad, UMR Qualisud, Montpellier, France
- Qualisud, Univ Montpellier, Avignon Université, Cirad, Institut Agro, IRD, Université de La Réunion, Montpellier, France
| | - Claire Lanaud
- Cirad, UMR Amélioration Génétique et Adaptation des Plantes Méditerranéennes et Tropicales, Montpellier, France
- Amélioration Génétique et Adaptation des Plantes Méditerranéennes et Tropicales, Univ Montpellier, Cirad, INRAE, Institut Agro, Montpellier, France
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15
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Zhou L, Xu Z, Wen Z, Lu M, Wang Z, Zhang Y, Zhou H, Jin M. Combined adaptive evolution and transcriptomic profiles reveal aromatic aldehydes tolerance mechanisms in Yarrowia lipolytica. BIORESOURCE TECHNOLOGY 2021; 329:124910. [PMID: 33677424 DOI: 10.1016/j.biortech.2021.124910] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/21/2021] [Accepted: 02/22/2021] [Indexed: 06/12/2023]
Abstract
Yarrowia lipolytica is an efficient oleaginous yeast, whereas its activity is typically reduced by inhibitors present in lignocellulosic hydrolysate. Understanding the response mechanism of Y. lipolytica to hydrolysate inhibitors and developing inhibitor tolerant strains are vital to lignocellulose valorization by this promising species. In this study, through adaptive laboratory evolution on three representative aromatic aldehyde inhibitors, evolved strains were obtained. Fermentation phenotype suggested that aromatic aldehydes conversion was one main reason for high tolerance of adapted strains. Transcriptome profiling analysis and reverse metabolic engineering confirmed that overexpressing the aldehyde ketone reductase gene YALI0_B07117g and aldehyde dehydrogenase gene YALI0_B01298g effectively converted aromatic aldehyde to corresponding alcohols and acids. The potential degradation pathways for aromatic aldehyde inhibitors in Y. lipolytica XYL+ were then discussed. This study provided insights to the aromatic aldehyde degradation in Y. lipolytica and a reliable basis for the development of aromatic aldehyde tolerant strains.
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Affiliation(s)
- Linlin Zhou
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, Nanjing 210094, China
| | - Zhaoxian Xu
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, Nanjing 210094, China
| | - Zhiqiang Wen
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, Nanjing 210094, China
| | - Minrui Lu
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, Nanjing 210094, China
| | - Zedi Wang
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, Nanjing 210094, China
| | - Yuwei Zhang
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, Nanjing 210094, China
| | - Huarong Zhou
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, Nanjing 210094, China
| | - Mingjie Jin
- School of Environmental and Biological Engineering, Nanjing University of Science & Technology, Nanjing 210094, China.
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16
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Analysis of the response of the cell membrane of Saccharomyces cerevisiae during the detoxification of common lignocellulosic inhibitors. Sci Rep 2021; 11:6853. [PMID: 33767301 PMCID: PMC7994549 DOI: 10.1038/s41598-021-86135-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 03/11/2021] [Indexed: 01/31/2023] Open
Abstract
Gaining an in-depth understanding of the response of Saccharomyces cerevisiae to the different inhibitors generated during the pretreatment of lignocellulosic material is driving the development of new strains with higher inhibitor tolerances. The objective of this study is to assess, using flow cytometry, how three common inhibitors (vanillin, furfural, and acetic acid) affect the membrane potential, the membrane permeability and the concentration of reactive oxygen species (ROS) during the different fermentations. The membrane potential decreased during the detoxification phase and reflected on the different mechanisms of the toxicity of the inhibitors. While vanillin and furfural caused a metabolic inhibition and a gradual depolarization, acetic acid toxicity was related to fast acidification of the cytosol, causing an immediate depolarization. In the absence of acetic acid, ethanol increased membrane permeability, indicating a possible acquired tolerance to ethanol due to an adaptive response to acetic acid. The intracellular ROS concentration also increased in the presence of the inhibitors, indicating oxidative stress. Measuring these features with flow cytometry allows a real-time assessment of the stress of a cell culture, which can be used in the development of new yeast strains and to design new propagation strategies to pre-adapt the cell cultures to the inhibitors.
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17
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Langsdorf A, Volkmar M, Holtmann D, Ulber R. Material utilization of green waste: a review on potential valorization methods. BIORESOUR BIOPROCESS 2021; 8:19. [PMID: 38650228 PMCID: PMC10991214 DOI: 10.1186/s40643-021-00367-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/03/2021] [Indexed: 01/09/2023] Open
Abstract
Considering global developments like climate change and the depletion of fossil resources, the use of new and sustainable feedstocks such as lignocellulosic biomass becomes inevitable. Green waste comprises heterogeneous lignocellulosic biomass with low lignin content, which does not stem from agricultural processes or purposeful cultivation and therefore mainly arises in urban areas. So far, the majority of green waste is being composted or serves as feedstock for energy production. Here, the hitherto untapped potential of green waste for material utilization instead of conventional recycling is reviewed. Green waste is a promising starting material for the direct extraction of valuable compounds, the chemical and fermentative conversion into basic chemicals as well as the manufacturing of functional materials like electrodes for electro-biotechnological applications through carbonization. This review serves as a solid foundation for further work on the valorization of green waste.
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Affiliation(s)
- Alexander Langsdorf
- Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390, Giessen, Germany
| | - Marianne Volkmar
- Institute of Bioprocess Engineering, University of Kaiserslautern, Gottlieb-Daimler-Strasse 49, 67663, Kaiserslautern, Germany
| | - Dirk Holtmann
- Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Wiesenstrasse 14, 35390, Giessen, Germany.
| | - Roland Ulber
- Institute of Bioprocess Engineering, University of Kaiserslautern, Gottlieb-Daimler-Strasse 49, 67663, Kaiserslautern, Germany
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18
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Corchado-Lopo C, Martínez-Avila O, Marti E, Llimós J, Busquets AM, Kucera D, Obruca S, Llenas L, Ponsá S. Brewer's spent grain as a no-cost substrate for polyhydroxyalkanoates production: Assessment of pretreatment strategies and different bacterial strains. N Biotechnol 2021; 62:60-67. [PMID: 33516825 DOI: 10.1016/j.nbt.2021.01.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 01/19/2021] [Accepted: 01/24/2021] [Indexed: 11/25/2022]
Abstract
Polyhydroxyalkanoates (PHAs) are polyesters of significant interest due to their biodegradability and properties similar to petroleum-derived plastics, as well as the fact that they can be produced from renewable sources such as by-product streams. In this study, brewer's spent grain (BSG), the main by-product of the brewing industry, was subjected to a set of physicochemical pretreatments and their effect on the release of reducing sugars (RS) was evaluated. The RS obtained were used as a substrate for further PHA production in Burkholderia cepacia, Bacillus cereus, and Cupriavidus necator in liquid cultures. Although some pretreatments proved efficient in releasing RS (acid-thermal pretreatment up to 42.1 gRS L-1 and 0.77 gRS g-1 dried BSG), the generation of inhibitors in such scenarios likely affected PHA production compared with the process run without pretreatment (direct enzymatic hydrolysis of BSG). Thus, the maximum PHA accumulation from BSG hydrolysates was found in the reference case with 0.31 ± 0.02 g PHA per g cell dried weight, corresponding to 1.13 ± 0.06 g L-1 and a PHA yield of 23 ± 1 mg g-1 BSG. It was also found that C. necator presented the highest PHA accumulation of the tested strains followed closely by B. cepacia, reaching their maxima at 48 h. Although BSG has been used as a source for other bioproducts, these results show the potential of this by-product as a no-cost raw material for producing PHAs in a waste valorization and circular economy scheme.
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Affiliation(s)
- Carlos Corchado-Lopo
- BETA Technological Center, TECNIO Network, University of Vic-Central University of Catalonia, Carrer de la Laura 13, 08500 Vic, Spain.
| | - Oscar Martínez-Avila
- BETA Technological Center, TECNIO Network, University of Vic-Central University of Catalonia, Carrer de la Laura 13, 08500 Vic, Spain.
| | - Elisabet Marti
- BETA Technological Center, TECNIO Network, University of Vic-Central University of Catalonia, Carrer de la Laura 13, 08500 Vic, Spain.
| | - Jordi Llimós
- BETA Technological Center, TECNIO Network, University of Vic-Central University of Catalonia, Carrer de la Laura 13, 08500 Vic, Spain.
| | - Anna María Busquets
- BETA Technological Center, TECNIO Network, University of Vic-Central University of Catalonia, Carrer de la Laura 13, 08500 Vic, Spain.
| | - Dan Kucera
- Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic.
| | - Stanislav Obruca
- Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00 Brno, Czech Republic.
| | - Laia Llenas
- BETA Technological Center, TECNIO Network, University of Vic-Central University of Catalonia, Carrer de la Laura 13, 08500 Vic, Spain.
| | - Sergio Ponsá
- BETA Technological Center, TECNIO Network, University of Vic-Central University of Catalonia, Carrer de la Laura 13, 08500 Vic, Spain.
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19
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Paes BG, Steindorff AS, Formighieri EF, Pereira IS, Almeida JRM. Physiological characterization and transcriptome analysis of Pichia pastoris reveals its response to lignocellulose-derived inhibitors. AMB Express 2021; 11:2. [PMID: 33389238 PMCID: PMC7779389 DOI: 10.1186/s13568-020-01170-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 12/16/2020] [Indexed: 12/11/2022] Open
Abstract
The negative effects of lignocellulose-derived inhibitors such as acetic acid and furaldehydes on microbial metabolism constitute a significant drawback to the usage of biomass feedstocks for the production of fuels and chemicals. The yeast Pichia pastoris has shown a great biotechnological potential for producing heterologous proteins and renewable chemicals. Despite its relevance, the performance of P. pastoris in presence of lignocellulose-derived inhibitors remains unclear. In this work, our results show for the first time the dose-dependent response of P. pastoris to acetic acid, furaldehydes (HMF and furfural), and sugarcane biomass hydrolysate, both at physiological and transcriptional levels. The yeast was able to grow in synthetic media with up to 6 g.L-1 acetic acid, 1.75 g.L-1 furaldehydes or hydrolysate diluted to 10% (v/v). However, its metabolism was completely hindered in presence of hydrolysate diluted to 30% (v/v). Additionally, the yeast was capable to co-consume acetic acid and glucose. At the transcriptional level, P. pastoris response to lignocellulose-derived inhibitors relays on the up-regulation of genes related to transmembrane transport, oxidoreductase activities, RNA processing, and the repression of pathways related to biosynthetic processes and central carbon metabolism. These results demonstrate a polygenetic response that involves detoxification activities, and maintenance of energy and cellular homeostasis. In this context, ALD4, OYE3, QOR2, NTL100, YCT1, and PPR1 were identified as target genes to improve P. pastoris tolerance. Altogether, this work provides valuable insights into the P. pastoris stress tolerance, which can be useful to expand its use in different bioprocesses.
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Affiliation(s)
- Barbara G Paes
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil
- Graduate Program of Molecular Biology, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, Brazil
| | - Andrei Stecca Steindorff
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil
| | - Eduardo F Formighieri
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil
| | - Ildinete Silva Pereira
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil
- Graduate Program of Molecular Biology, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, Brazil
| | - João Ricardo M Almeida
- Laboratory of Genetics and Biotechnology, Embrapa Agroenergia, Parque Estação Biológica, PqEB - W3 Norte Final s/no, Brasília, DF, 70.770-901, Brazil.
- Graduate Program of Microbial Biology, Department of Cell Biology, Institute of Biology, University of Brasilia, Brasília, Brazil.
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20
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Abatement of Inhibitors in Recycled Process Water from Biomass Fermentations Relieves Inhibition of a Saccharomyces cerevisiae Pentose Phosphate Pathway Mutant. FERMENTATION 2020. [DOI: 10.3390/fermentation6040107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Understanding the nature of fermentation inhibition in biomass hydrolysates and recycled fermentation process water is important for conversion of biomass to fuels and chemicals. This study used three mutants disrupted in genes important for tolerance to either oxidative stress, salinity, or osmolarity to ferment biomass hydrolysates in a xylose-fermenting Saccharomyces cerevisiae background. The S. cerevisiaeZWF1 mutant with heightened sensitivity to fermentation inhibitors was unable to ferment corn stover dilute-acid hydrolysate without conditioning of hydrolysate using a fungal strain, Coniochaeta ligniaria, to consume inhibitors. Growth of two other strains, a salt-sensitive HAL4 mutant and a GPD1 mutant sensitive to osmotic stress, was not negatively affected in hydrolysate compared to the parent xylose-metabolizing strain. In recycled fermentation process water, inhibition of the ZWF1 mutant could again be remediated by biological abatement, and no effect on growth was observed for any of the mutants compared to the parent strain.
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21
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Cabaneros Lopez P, Udugama IA, Thomsen ST, Roslander C, Junicke H, Iglesias MM, Gernaey KV. Transforming data to information: A parallel hybrid model for real-time state estimation in lignocellulosic ethanol fermentation. Biotechnol Bioeng 2020; 118:579-591. [PMID: 33002188 PMCID: PMC7894558 DOI: 10.1002/bit.27586] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 09/17/2020] [Accepted: 09/26/2020] [Indexed: 11/21/2022]
Abstract
Operating lignocellulosic fermentation processes to produce fuels and chemicals is challenging due to the inherent complexity and variability of the fermentation media. Real‐time monitoring is necessary to compensate for these challenges, but the traditional process monitoring methods fail to deliver actionable information that can be used to implement advanced control strategies. In this study, a hybrid‐modeling approach is presented to monitor cellulose‐to‐ethanol (EtOH) fermentations in real‐time. The hybrid approach uses a continuous‐discrete extended Kalman filter to reconciliate the predictions of a data‐driven model and a kinetic model and to estimate the concentration of glucose (Glu), xylose (Xyl), and EtOH. The data‐driven model is based on partial least squares (PLS) regression and predicts in real‐time the concentration of Glu, Xyl, and EtOH from spectra collected with attenuated total reflectance mid‐infrared spectroscopy. The estimations made by the hybrid approach, the data‐driven models and the internal model were compared in two validation experiments showing that the hybrid model significantly outperformed the PLS and improved the predictions of the internal model. Furthermore, the hybrid model delivered consistent estimates even when disturbances in the measurements occurred, demonstrating the robustness of the method. The consistency of the proposed hybrid model opens the doors towards the implementation of advanced feedback control schemes.
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Affiliation(s)
- Pau Cabaneros Lopez
- Department of Chemical and Biochemical Engineering, Process and Systems Engineering Center (PROSYS), Technical University of Denmark (DTU), Lyngby, Denmark
| | - Isuru A Udugama
- Department of Chemical and Biochemical Engineering, Process and Systems Engineering Center (PROSYS), Technical University of Denmark (DTU), Lyngby, Denmark
| | - Sune T Thomsen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | | | - Helena Junicke
- Department of Chemical and Biochemical Engineering, Process and Systems Engineering Center (PROSYS), Technical University of Denmark (DTU), Lyngby, Denmark
| | - Miguel M Iglesias
- Department of Chemical Engineering, CRETUS Institute, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Krist V Gernaey
- Department of Chemical and Biochemical Engineering, Process and Systems Engineering Center (PROSYS), Technical University of Denmark (DTU), Lyngby, Denmark
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22
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Persson M, Galbe M, Wallberg O. A strategy for synergistic ethanol yield and improved production predictability through blending feedstocks. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:156. [PMID: 32944072 PMCID: PMC7487856 DOI: 10.1186/s13068-020-01791-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 08/21/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND The integration of first- and second-generation bioethanol processes has the potential to accelerate the establishment of second-generation bioethanol on the market. Cofermenting pretreated wheat straw with a glucose-rich process stream, such as wheat grain hydrolysate, in a simultaneous saccharification and fermentation process could address the technical issues faced during the biological conversion of lignocellulose to ethanol. For example, doing so can increase the final ethanol concentration in the broth and mitigate the effects of inhibitors formed during the pretreatment. Previous research has indicated that blends of first- and second-generation substrates during simultaneous saccharification and fermentation have synergistic effects on the final ethanol yield, an important parameter in the process economy. In this study, enzymatic hydrolysis and simultaneous saccharification and fermentation were examined using blends of pretreated wheat straw and saccharified wheat grain at various ratios. The aim of this study was to determine the underlying mechanisms of the synergy of blending with regard to the yield and volumetric productivity of ethanol. RESULTS Replacing 25% of the pretreated wheat straw with wheat grain hydrolysate during simultaneous saccharification and fermentation was sufficient to decrease the residence time needed to deplete soluble glucose from 96 to 24 h and shift the rate-limiting step from ethanol production to the rate of enzymatic hydrolysis. Further, a synergistic effect on ethanol yield was observed with blended substrates, coinciding with lower glycerol production. Also, blending substrates had no effect on the yield of enzymatic hydrolysis. CONCLUSIONS The effects of substrate blending on the volumetric productivity of ethanol were attributed to changes in the relative rates of cell growth and cell death due to alterations in the concentrations of substrate and pretreatment-derived inhibitors. The synergistic effect of substrate blending on ethanol yield was attributed in part to the decreased production of cell mass and glycerol. Thus, it is preferable to perform simultaneous saccharification and fermentation with substrate blends rather than pure substrates with regard to yield, productivity, and the robustness of the process.
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Affiliation(s)
- Michael Persson
- Department of Chemical Engineering, Lund University, P.O. Box 124, 221 00 Lund, Sweden
| | - Mats Galbe
- Department of Chemical Engineering, Lund University, P.O. Box 124, 221 00 Lund, Sweden
| | - Ola Wallberg
- Department of Chemical Engineering, Lund University, P.O. Box 124, 221 00 Lund, Sweden
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23
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Erkan SB, Yatmaz E, Germec M, Turhan I. Effect of furfural concentration on ethanol production using
Saccharomyces cerevisiae
in an immobilized cells stirred‐tank bioreactor with glucose‐based medium and mathematical modeling. J FOOD PROCESS PRES 2020. [DOI: 10.1111/jfpp.14635] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | - Ercan Yatmaz
- Department of Food Engineering Akdeniz University Antalya Turkey
- Göynük Culinary Arts Vocational School Akdeniz University Antalya Turkey
| | - Mustafa Germec
- Department of Food Engineering Akdeniz University Antalya Turkey
| | - Irfan Turhan
- Department of Food Engineering Akdeniz University Antalya Turkey
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24
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Mahboubi A, Elyasi S, Doyen W, De Wever H, Taherzadeh MJ. Concentration-driven reverse membrane bioreactor for the fermentation of highly inhibitory lignocellulosic hydrolysate. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.01.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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25
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Candido JP, Claro EMT, de Paula CBC, Shimizu FL, de Oliveria Leite DAN, Brienzo M, de Angelis DDF. Detoxification of sugarcane bagasse hydrolysate with different adsorbents to improve the fermentative process. World J Microbiol Biotechnol 2020; 36:43. [DOI: 10.1007/s11274-020-02820-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 02/25/2020] [Indexed: 12/11/2022]
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26
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Global Analysis of Furfural-Induced Genomic Instability Using a Yeast Model. Appl Environ Microbiol 2019; 85:AEM.01237-19. [PMID: 31300396 DOI: 10.1128/aem.01237-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 07/01/2019] [Indexed: 02/07/2023] Open
Abstract
Furfural is an important renewable precursor for multiple commercial chemicals and fuels; a main inhibitor existing in cellulosic hydrolysate, which is used for bioethanol fermentation; and a potential carcinogen, as well. Using a genetic system in Saccharomyces cerevisiae that allows detection of crossover events, we observed that the frequency of mitotic recombination was elevated by 1.5- to 40-fold when cells were treated with 0.1 g/liter to 20 g/liter furfural. Analysis of the gene conversion tracts associated with crossover events suggested that most furfural-induced recombination resulted from repair of DNA double-strand breaks (DSBs) that occurred in the G1 phase. Furfural was incapable of breaking DNA directly in vitro but could trigger DSBs in vivo related to reactive oxygen species accumulation. By whole-genome single nucleotide polymorphism (SNP) microarray and sequencing, furfural-induced genomic alterations that range from single base substitutions, loss of heterozygosity, and chromosomal rearrangements to aneuploidy were explored. At the whole-genome level, furfural-induced events were evenly distributed across 16 chromosomes but were enriched in high-GC-content regions. Point mutations, particularly the C-to-T/G-to-A transitions, were significantly elevated in furfural-treated cells compared to wild-type cells. This study provided multiple novel insights into the global effects of furfural on genomic stability.IMPORTANCE Whether and how furfural affects genome integrity have not been clarified. Using a Saccharomyces cerevisiae model, we found that furfural exposure leads to in vivo DSBs and elevation in mitotic recombination by orders of magnitude. Gross chromosomal rearrangements and aneuploidy events also occurred at a higher frequency in furfural-treated cells. In a genome-wide analysis, we show that the patterns of mitotic recombination and point mutations differed dramatically in furfural-treated cells and wild-type cells.
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27
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Sarawan C, Suinyuy TN, Sewsynker-Sukai Y, Gueguim Kana EB. Optimized activated charcoal detoxification of acid-pretreated lignocellulosic substrate and assessment for bioethanol production. BIORESOURCE TECHNOLOGY 2019; 286:121403. [PMID: 31078980 DOI: 10.1016/j.biortech.2019.121403] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/28/2019] [Accepted: 04/29/2019] [Indexed: 06/09/2023]
Abstract
This study optimized an activated charcoal (AC) detoxification method for the reduction of three different fermentation inhibitor compounds, while minimising the reducing sugar loss from acid-pretreated sorghum leaf (SL) wastes. Process optimization demonstrated a 98%, 88% and 37% removal efficiency for furfural, 5-hydroxymethylfurfural (HMF) and acetic acid respectively, with a 7% reducing sugar loss. Subsequently, the logistic and modified Gompertz models were used to comparatively evaluate the kinetics of Saccharomyces cerevisiae growth and ethanol production using the non-detoxified (NDF) and optimized detoxified (ODF) substrate. Yeast cell growth and bioethanol kinetic coefficients revealed that the ODF process was more effective than the NDF system. The experimental data generated from this study revealed that a suitable, cost-effective AC detoxification enhanced cell growth and bioethanol production efficiency. These findings pave the way for biomass pretreatment, detoxification and bioethanol process development using lignocellulosic wastes.
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Affiliation(s)
- Caitlyn Sarawan
- University of KwaZulu-Natal, School of Life Sciences, Pietermaritzburg, South Africa
| | - T N Suinyuy
- University of KwaZulu-Natal, School of Life Sciences, Pietermaritzburg, South Africa
| | - Y Sewsynker-Sukai
- University of KwaZulu-Natal, School of Life Sciences, Pietermaritzburg, South Africa
| | - E B Gueguim Kana
- University of KwaZulu-Natal, School of Life Sciences, Pietermaritzburg, South Africa.
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Favaro L, Jansen T, van Zyl WH. Exploring industrial and naturalSaccharomyces cerevisiaestrains for the bio-based economy from biomass: the case of bioethanol. Crit Rev Biotechnol 2019; 39:800-816. [DOI: 10.1080/07388551.2019.1619157] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Lorenzo Favaro
- Department of Agronomy Food Natural resources Animals and Environment (DAFNAE), University of Padova, Legnaro, Italy
| | - Trudy Jansen
- Department of Microbiology, Stellenbosch University, Stellenbosch, South Africa
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Zhou P, Yao R, Zhang H, Bao J. Unique glucose oxidation catalysis of
Gluconobacter oxydans
constitutes an efficient cellulosic gluconic acid fermentation free of inhibitory compounds disturbance. Biotechnol Bioeng 2019; 116:2191-2199. [DOI: 10.1002/bit.27020] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 04/14/2019] [Accepted: 05/09/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Pingping Zhou
- School of BioengineeringState Key Laboratory of Bioreactor Engineering, East China University of Science and TechnologyShanghai China
| | - Ruimiao Yao
- School of BioengineeringState Key Laboratory of Bioreactor Engineering, East China University of Science and TechnologyShanghai China
| | - Hongsen Zhang
- School of BioengineeringState Key Laboratory of Bioreactor Engineering, East China University of Science and TechnologyShanghai China
- Key Laboratory of Enzyme Engineering of Agricultural MicrobiologyMinistry of AgricultureCollege of Life ScienceHenan Agricultural UniversityZhengzhou China
| | - Jie Bao
- School of BioengineeringState Key Laboratory of Bioreactor Engineering, East China University of Science and TechnologyShanghai China
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30
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Estrada-Martínez R, Favela-Torres E, Soto-Cruz NO, Escalona-Buendía HB, Saucedo-Castañeda G. A Mild Thermal Pre-treatment of the Organic Fraction of Municipal Wastes Allows High Ethanol Production by Direct Solid-state Fermentation. BIOTECHNOL BIOPROC E 2019. [DOI: 10.1007/s12257-019-0032-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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31
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Nayak A, Bhushan B. An overview of the recent trends on the waste valorization techniques for food wastes. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 233:352-370. [PMID: 30590265 DOI: 10.1016/j.jenvman.2018.12.041] [Citation(s) in RCA: 130] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 12/09/2018] [Accepted: 12/14/2018] [Indexed: 05/05/2023]
Abstract
A critical and up-to-date review has been conducted on the latest individual valorization technologies aimed at the generation of value-added by-products from food wastes in the form of bio-fuels, bio-materials, value added components and bio-based adsorbents. The aim is to examine the associated advantages and drawbacks of each technique separately along with the assessment of process parameters affecting the efficiency of the generation of the bio-based products. Challenges faced during the processing of the wastes to each of the bio-products have been explained and future scopes stated. Among the many hurdles encountered in the successful and high yield generation of the bio-products is the complexity and variability in the composition of the food wastes along with the high inherent moisture content. Also, individual technologies have their own process configurations and operating parameters which may affect the yield and composition of the desired end product. All these require extensive study of the composition of the food wastes followed by their effective pre-treatments, judicial selection of the technological parameters and finally optimization of not only the process configurations but also in relation to the input food waste material. Attempt has also been made to address the hurdles faced during the implementation of such technologies on an industrial scale.
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Affiliation(s)
- A Nayak
- Innovació i Recerca Industrial I Sostenible, S.L., 08860, Spain; Graphic Era University, Dehradun, 248002, India.
| | - Brij Bhushan
- Graphic Era University, Dehradun, 248002, India; Chemical Engineering Department, Universitat Politechnica Catalunya, UPC-BarcelonaTECH, Barcelona, 08860, Spain
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Štafa A, Žunar B, Pranklin A, Zandona A, Svetec-Miklenić M, Šantek B, Svetec IK. Novel Approach in the Construction of
Bioethanol-Producing Saccharomyces cerevisiae Hybrids §. Food Technol Biotechnol 2019; 57:5-16. [PMID: 31316272 PMCID: PMC6600304 DOI: 10.17113/ftb.57.01.19.5685] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Bioethanol production from lignocellulosic hydrolysates requires a producer strain that tolerates both the presence of growth and fermentation inhibitors and high ethanol concentrations. Therefore, we constructed heterozygous intraspecies hybrid diploids of Saccharomyces cerevisiae by crossing two natural S. cerevisiae isolates, YIIc17_E5 and UWOPS87-2421, a good ethanol producer found in wine and a strain from the flower of the cactus Opuntia megacantha resistant to inhibitors found in lignocellulosic hydrolysates, respectively. Hybrids grew faster than parental strains in the absence and in the presence of acetic and levulinic acids and 2-furaldehyde, inhibitors frequently found in lignocellulosic hydrolysates, and the overexpression of YAP1 gene increased their survival. Furthermore, although originating from the same parental strains, hybrids displayed different fermentative potential in a CO2 production test, suggesting genetic variability that could be used for further selection of desirable traits. Therefore, our results suggest that the construction of intraspecies hybrids coupled with the use of genetic engineering techniques is a promising approach for improvement or development of new biotechnologically relevant strains of S. cerevisiae. Moreover, it was found that the success of gene targeting (gene targeting fidelity) in natural S. cerevisiae isolates (YIIc17_E5α and UWOPS87-2421α) was strikingly lower than in laboratory strains and the most frequent off-targeting event was targeted chromosome duplication.
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Affiliation(s)
- Anamarija Štafa
- University of Zagreb, Faculty of Food Technology and Biotechnology, Department of Biochemical Engineering, Laboratory for Biology and Microbial Genetics, Kršnjavoga 25, 10000 Zagreb, Croatia
| | - Bojan Žunar
- University of Zagreb, Faculty of Food Technology and Biotechnology, Department of Biochemical Engineering, Laboratory for Biology and Microbial Genetics, Kršnjavoga 25, 10000 Zagreb, Croatia
| | - Andrea Pranklin
- University of Zagreb, Faculty of Food Technology and Biotechnology, Department of Biochemical Engineering, Laboratory for Biology and Microbial Genetics, Kršnjavoga 25, 10000 Zagreb, Croatia
| | - Antonio Zandona
- University of Zagreb, Faculty of Food Technology and Biotechnology, Department of Biochemical Engineering, Laboratory for Biology and Microbial Genetics, Kršnjavoga 25, 10000 Zagreb, Croatia
| | - Marina Svetec-Miklenić
- University of Zagreb, Faculty of Food Technology and Biotechnology, Department of Biochemical Engineering, Laboratory for Biology and Microbial Genetics, Kršnjavoga 25, 10000 Zagreb, Croatia
| | - Božidar Šantek
- University of Zagreb, Faculty of Food Technology and Biotechnology, Department of Biochemical Engineering, Laboratory for Biochemical Engineering, Industrial Microbiology and Malting and Brewing Technology, Kačićeva 28, 10000 Zagreb, Croatia
| | - Ivan Krešimir Svetec
- University of Zagreb, Faculty of Food Technology and Biotechnology, Department of Biochemical Engineering, Laboratory for Biology and Microbial Genetics, Kršnjavoga 25, 10000 Zagreb, Croatia
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33
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Mithra MG, Jeeva ML, Sajeev MS, Padmaja G. Comparison of ethanol yield from pretreated lignocellulo-starch biomass under fed-batch SHF or SSF modes. Heliyon 2018; 4:e00885. [PMID: 30417150 PMCID: PMC6218405 DOI: 10.1016/j.heliyon.2018.e00885] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 09/07/2018] [Accepted: 10/23/2018] [Indexed: 11/02/2022] Open
Abstract
The ethanol yields from lignocellulo-starch biomass (peels of sweet potato, elephant foot yam, tannia, greater yam and beet root) by fed-batch separate hydrolysis and fermentation (F-SHF) and simultaneous saccharification and fermentation (F-SSF) using Saccharomyces cerevisiae were compared. Fed-batch saccharification of steam or dilute sulphuric acid pretreated biomass enhanced the reducing sugar yield which resulted in high RS consumption, volumetric ethanol productivity and ethanol yield during the first 24 h fermentation under F-SHF mode, while continuous production and utilization of reducing sugars occurred up to 72 h in F-SSF. Dilute sulphuric acid pretreated residues under F-SHF gave higher ethanol yield (34-43 g/L) and productivity (274-346 ml/kg dry biomass) than steam pretreatment (27-36 g/L and 223-295 ml/kg respectively), while F-SSF was superior for steam pretreated peels of sweet potato, elephant foot yam and tannia giving ethanol yields from 281 to 302 ml/kg. Glucose and xylose were present in all the hydrolysates with a preponderance of glucose and fermentation resulted in significant reduction in glucose levels in both F-SHF and F-SSF. Higher levels of total soluble phenolics and hydroxymethyl furfural were observed in the hydrolysates from dilute sulphuric acid pretreatment and yeast assimilated/detoxified part of the inhibitors, while only trivial amounts of furfural were present due to the low xylose content in the hydrolysates. Continuous formation led to higher accumulation of inhibitors in F-SSF despite supplementation with the detoxification mix comprising Tween 20, polyethylene glycol and sodium borohydride. F-SHF of dilute sulphuric acid pretreated biomass could be considered as a comparatively advantageous process where only one time feeding of enzyme cocktail and yeast was adopted compared to multiple feeds of enzymes and yeast along with other additives such as detoxification mix or nutrient solution in F-SSF.
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Affiliation(s)
- M G Mithra
- Division of Crop Utilization, ICAR- Central Tuber Crops Research Institute, Thiruvananthapuram 695 017, Kerala, India
| | - M L Jeeva
- Division of Crop Protection, ICAR- Central Tuber Crops Research Institute, Thiruvananthapuram 695 017, Kerala, India
| | - M S Sajeev
- Division of Crop Utilization, ICAR- Central Tuber Crops Research Institute, Thiruvananthapuram 695 017, Kerala, India
| | - G Padmaja
- Division of Crop Utilization, ICAR- Central Tuber Crops Research Institute, Thiruvananthapuram 695 017, Kerala, India
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34
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Hu M, Wang J, Gao Q, Bao J. Converting lignin derived phenolic aldehydes into microbial lipid by Trichosporon cutaneum. J Biotechnol 2018; 281:81-86. [DOI: 10.1016/j.jbiotec.2018.06.341] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 06/05/2018] [Accepted: 06/16/2018] [Indexed: 12/25/2022]
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Technological Processes for Conversion of Lignocellulosic Biomass to Bioethanol. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2017. [DOI: 10.22207/jpam.11.4.27] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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36
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Wannawilai S, Chisti Y, Sirisansaneeyakul S. A model of furfural-inhibited growth and xylitol production by Candida magnoliae TISTR 5663. FOOD AND BIOPRODUCTS PROCESSING 2017. [DOI: 10.1016/j.fbp.2017.07.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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37
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Liu YF, Hsieh CW, Chang YS, Wung BS. Effect of acetic acid on ethanol production by Zymomonas mobilis mutant strains through continuous adaptation. BMC Biotechnol 2017; 17:63. [PMID: 28764759 PMCID: PMC5540488 DOI: 10.1186/s12896-017-0385-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 07/25/2017] [Indexed: 02/03/2023] Open
Abstract
Background Acetic acid is a predominant by-product of lignocellulosic biofuel process, which inhibits microbial biocatalysts. Development of bacterial strains that are tolerant to acetic acid is challenging due to poor understanding of the underlying molecular mechanisms. Results In this study, we generated and characterized two acetic acid-tolerant strains of Zymomonas mobilis using N-methyl-N′-nitro-N-nitrosoguanidine (NTG)-acetate adaptive breeding. Two mutants, ZMA-142 and ZMA-167, were obtained, showing a significant growth rate at a concentration of 244 mM sodium acetate, while the growth of Z. mobilis ATCC 31823 were completely inhibited in presence of 195 mM sodium acetate. Our data showed that acetate-tolerance of ZMA-167 was attributed to a co-transcription of nhaA from ZMO0117, whereas the co-transcription was absent in ATCC 31823 and ZMA-142. Moreover, ZMA-142 and ZMA-167 exhibited a converstion rate (practical ethanol yield to theorical ethanol yield) of 90.16% and 86% at 195 mM acetate-pH 5 stress condition, respectively. We showed that acid adaptation of ZMA-142 and ZMA-167 to 146 mM acetate increased ZMA-142 and ZMA-167 resulted in an increase in ethanol yield by 32.21% and 21.16% under 195 mM acetate-pH 5 stress condition, respectively. Conclusion The results indicate the acetate-adaptive seed culture of acetate-tolerant strains, ZMA-142 and ZMA-167, could enhance the ethanol production during fermentation.
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Affiliation(s)
- Yu-Fan Liu
- Division of Allergy, Department of Pediatrics, Chung-Shan Medical University Hospital, Taichung, Taiwan.,Department of Biomedical Sciences, College of Medicine Sciences and Technology, Chung Shan Medical University, Taichung, Taiwan
| | - Chia-Wen Hsieh
- Department of Microbiology, Immunology and Biopharmaceuticals, National Chiayi University, Chiayi, Taiwan.
| | - Yao-Sheng Chang
- Department of Microbiology, Immunology and Biopharmaceuticals, National Chiayi University, Chiayi, Taiwan
| | - Being-Sun Wung
- Department of Microbiology, Immunology and Biopharmaceuticals, National Chiayi University, Chiayi, Taiwan
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38
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Wang S, Yang J. Isoprenoids Production from Lipid-Extracted Microalgal Biomass Residues Using Engineered E. coli. Molecules 2017; 22:molecules22060960. [PMID: 28598364 PMCID: PMC6152769 DOI: 10.3390/molecules22060960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 06/01/2017] [Accepted: 06/07/2017] [Indexed: 11/16/2022] Open
Abstract
Microalgae are recognized as a third generation feedstock for biofuel production due to their rapid growth rates and lignin-free characteristics. In this study, a lipid extracted microalgal biomass residues was used as the raw material to produce isoprene, α-pinene and β-pinene with an engineered E. coli strain. We adopted an optimal sulfuric acid hydrolysis method (1:7 ratio of solid to acid solution, 32% (w/v) concentration of sulfuric acid solution at 90 °C for 90 min) to efficiently convert holocellulose into glucose efficiently (6.37 g/L). Futhermore, we explored a novel detoxification strategy (phosphoric acid/calcium hydroxide) to remove inhibitors and notably acetic acid, furfural and 5-hydroxymethylfurfural (5-HMF) were reduced by 5.32%, different number given later 99.19% and 98.22%, respectively. Finally, the fermentation concentrations of isoprene (223.23 mg/L), α-pinene (382.21 μg/L) and β-pinene (17.4 mg/L) were achieved using the detoxified hydrolysate as the carbon source, equivalent to approximately 86.02%, 90.16% and 88.32% of those produced by the engineered E. coli strain fermented on pure glucose, respectively.
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Affiliation(s)
- Sumeng Wang
- Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao 266109, China.
| | - Jianming Yang
- Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao 266109, China.
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Evolution of a Biomass-Fermenting Bacterium To Resist Lignin Phenolics. Appl Environ Microbiol 2017; 83:AEM.00289-17. [PMID: 28363966 DOI: 10.1128/aem.00289-17] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 03/24/2017] [Indexed: 02/05/2023] Open
Abstract
Increasing the resistance of plant-fermenting bacteria to lignocellulosic inhibitors is useful to understand microbial adaptation and to develop candidate strains for consolidated bioprocessing. Here, we study and improve inhibitor resistance in Clostridium phytofermentans (also called Lachnoclostridium phytofermentans), a model anaerobe that ferments lignocellulosic biomass. We survey the resistance of this bacterium to a panel of biomass inhibitors and then evolve strains that grow in increasing concentrations of the lignin phenolic, ferulic acid, by automated, long-term growth selection in an anaerobic GM3 automat. Ultimately, strains resist multiple inhibitors and grow robustly at the solubility limit of ferulate while retaining the ability to ferment cellulose. We analyze genome-wide transcription patterns during ferulate stress and genomic variants that arose along the ferulate growth selection, revealing how cells adapt to inhibitors through changes in gene dosage and regulation, membrane fatty acid structure, and the surface layer. Collectively, this study demonstrates an automated framework for in vivo directed evolution of anaerobes and gives insight into the genetic mechanisms by which bacteria survive exposure to chemical inhibitors.IMPORTANCE Fermentation of plant biomass is a key part of carbon cycling in diverse ecosystems. Further, industrial biomass fermentation may provide a renewable alternative to fossil fuels. Plants are primarily composed of lignocellulose, a matrix of polysaccharides and polyphenolic lignin. Thus, when microorganisms degrade lignocellulose to access sugars, they also release phenolic and acidic inhibitors. Here, we study how the plant-fermenting bacterium Clostridium phytofermentans resists plant inhibitors using the lignin phenolic, ferulic acid. We examine how the cell responds to abrupt ferulate stress by measuring changes in gene expression. We evolve increasingly resistant strains by automated, long-term cultivation at progressively higher ferulate concentrations and sequence their genomes to identify mutations associated with acquired ferulate resistance. Our study develops an inhibitor-resistant bacterium that ferments cellulose and provides insights into genomic evolution to resist chemical inhibitors.
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40
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Wannawilai S, Lee WC, Chisti Y, Sirisansaneeyakul S. Furfural and glucose can enhance conversion of xylose to xylitol by Candida magnoliae TISTR 5663. J Biotechnol 2017; 241:147-157. [DOI: 10.1016/j.jbiotec.2016.11.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 11/17/2016] [Accepted: 11/25/2016] [Indexed: 11/30/2022]
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41
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Li J, Shi S, Adhikari S, Tu M. Inhibition effect of aromatic aldehydes on butanol fermentation by Clostridium acetobutylicum. RSC Adv 2017. [DOI: 10.1039/c6ra25706b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The ortho-substituted 2-hydroxybenzaldehyde caused 20-fold stronger inhibition than meta- and para-substituted analogues of 3- and 4-hydroxybenzaldehydes.
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Affiliation(s)
- Jing Li
- Department of Biosystems Engineering
- Auburn University
- USA
| | - Suan Shi
- Hawaii Natural Energy Institute
- University of Hawaii
- Honolulu
- USA
| | | | - Maobing Tu
- Department of Biomedical
- Chemical and Environmental Engineering
- University of Cincinnati
- Cincinnati
- USA
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42
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Jung YH, Kim S, Yang J, Seo JH, Kim KH. Intracellular metabolite profiling of Saccharomyces cerevisiae evolved under furfural. Microb Biotechnol 2016; 10:395-404. [PMID: 27928897 PMCID: PMC5328829 DOI: 10.1111/1751-7915.12465] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 11/01/2016] [Accepted: 11/02/2016] [Indexed: 12/21/2022] Open
Abstract
Furfural, one of the most common inhibitors in pre‐treatment hydrolysates, reduces the cell growth and ethanol production of yeast. Evolutionary engineering has been used as a selection scheme to obtain yeast strains that exhibit furfural tolerance. However, the response of Saccharomyces cerevisiae to furfural at the metabolite level during evolution remains unknown. In this study, evolutionary engineering and metabolomic analyses were applied to determine the effects of furfural on yeasts and their metabolic response to continuous exposure to furfural. After 50 serial transfers of cultures in the presence of furfural, the evolved strains acquired the ability to stably manage its physiological status under the furfural stress. A total of 98 metabolites were identified, and their abundance profiles implied that yeast metabolism was globally regulated. Under the furfural stress, stress‐protective molecules and cofactor‐related mechanisms were mainly induced in the parental strain. However, during evolution under the furfural stress, S. cerevisiae underwent global metabolic allocations to quickly overcome the stress, particularly by maintaining higher levels of metabolites related to energy generation, cofactor regeneration and recovery from cellular damage. Mapping the mechanisms of furfural tolerance conferred by evolutionary engineering in the present study will be led to rational design of metabolically engineered yeasts.
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Affiliation(s)
- Young Hoon Jung
- School of Food Science and Biotechnology, Kyungpook National University, Daegu, 41566, South Korea
| | - Sooah Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - Jungwoo Yang
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
| | - Jin-Ho Seo
- Department of Agricultural Biotechnology and Center for Food and Bioconvergence, Seoul National University, Seoul, 08826, South Korea
| | - Kyoung Heon Kim
- Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea
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43
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Microwaves as a pretreatment for enhancing enzymatic hydrolysis of pineapple industrial waste for bioethanol production. FOOD AND BIOPRODUCTS PROCESSING 2016. [DOI: 10.1016/j.fbp.2016.07.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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44
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Guo W, Chen Y, Wei N, Feng X. Investigate the Metabolic Reprogramming of Saccharomyces cerevisiae for Enhanced Resistance to Mixed Fermentation Inhibitors via 13C Metabolic Flux Analysis. PLoS One 2016; 11:e0161448. [PMID: 27532329 PMCID: PMC4988770 DOI: 10.1371/journal.pone.0161448] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 08/07/2016] [Indexed: 11/18/2022] Open
Abstract
The fermentation inhibitors from the pretreatment of lignocellulosic materials, e.g., acetic acid and furfural, are notorious due to their negative effects on the cell growth and chemical production. However, the metabolic reprogramming of the cells under these stress conditions, especially metabolic response for resistance to mixed inhibitors, has not been systematically investigated and remains mysterious. Therefore, in this study, 13C metabolic flux analysis (13C-MFA), a powerful tool to elucidate the intracellular carbon flux distributions, has been applied to two Saccharomyces cerevisiae strains with different tolerances to the inhibitors under acetic acid, furfural, and mixed (i.e., acetic acid and furfural) stress conditions to unravel the key metabolic responses. By analyzing the intracellular carbon fluxes as well as the energy and cofactor utilization under different conditions, we uncovered varied metabolic responses to different inhibitors. Under acetate stress, ATP and NADH production was slightly impaired, while NADPH tended towards overproduction. Under furfural stress, ATP and cofactors (including both NADH and NADPH) tended to be overproduced. However, under dual-stress condition, production of ATP and cofactors was severely impaired due to synergistic stress caused by the simultaneous addition of two fermentation inhibitors. Such phenomenon indicated the pivotal role of the energy and cofactor utilization in resisting the mixed inhibitors of acetic acid and furfural. Based on the discoveries, valuable insights are provided to improve the tolerance of S. cerevisiae strain and further enhance lignocellulosic fermentation.
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Affiliation(s)
- Weihua Guo
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, United States of America
| | - Yingying Chen
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, United States of America
| | - Na Wei
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, United States of America
- * E-mail: (NW); (XF)
| | - Xueyang Feng
- Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, United States of America
- * E-mail: (NW); (XF)
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Suko AV, Bura R. Enhanced Xylitol and Ethanol Yields by Fermentation Inhibitors in Steam-Pretreated Lignocellulosic Biomass. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1089/ind.2015.0026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Azra Vajzovic Suko
- University of Washington, School of Environmental and Forest Sciences, Seattle, WA
| | - Renata Bura
- University of Washington, School of Environmental and Forest Sciences, Seattle, WA
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46
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Velmurugan R, Incharoensakdi A. Proper ultrasound treatment increases ethanol production from simultaneous saccharification and fermentation of sugarcane bagasse. RSC Adv 2016. [DOI: 10.1039/c6ra17792a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
To improve the saccharification and fermentation processes, proper ultrasound was applied which resulted in the presence of cellulase complex with improved β-glucosidase ratio leading to enhanced overall ethanol yield.
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47
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Shen Y, Fatemeh T, Tang L, Cai Z. Quantitative metabolic network profiling of Escherichia coli: An overview of analytical methods for measurement of intracellular metabolites. Trends Analyt Chem 2016. [DOI: 10.1016/j.trac.2015.07.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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48
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Catalytic conversion of sugarcane bagasse to cellulosic ethanol: TiO2 coupled nanocellulose as an effective hydrolysis enhancer. Carbohydr Polym 2016; 136:700-9. [DOI: 10.1016/j.carbpol.2015.09.098] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 09/17/2015] [Accepted: 09/26/2015] [Indexed: 11/17/2022]
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49
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Chen Y, Sheng J, Jiang T, Stevens J, Feng X, Wei N. Transcriptional profiling reveals molecular basis and novel genetic targets for improved resistance to multiple fermentation inhibitors in Saccharomyces cerevisiae. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:9. [PMID: 26766964 PMCID: PMC4710983 DOI: 10.1186/s13068-015-0418-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 12/15/2015] [Indexed: 05/07/2023]
Abstract
BACKGROUND Lignocellulosic biomass is a promising source of renewable biofuels. However, pretreatment of lignocellulosic biomass generates fermentation inhibitors that adversely affect the growth of industrial microorganisms such as Saccharomyces cerevisiae and prevent economic production of lignocellulosic biofuels. A critical challenge on developing S. cerevisiae with improved inhibitor resistance lies in incomplete understanding of molecular basis for inhibitor stress response and limited information on effective genetic targets for increasing yeast resistance to mixed fermentation inhibitors. In this study, we applied comparative transcriptomic analysis to determine the molecular basis for acetic acid and/or furfural resistance in S. cerevisiae. RESULTS We recently developed a yeast strain YC1 with superior resistance to acetic acid, furfural, and their mixture through inverse metabolic engineering. In this study, we first determined transcriptional changes through RNA sequencing in YC1 versus the wild-type strain S-C1 under three different inhibitor conditions, including acetic acid alone, furfural alone, and mixture of acetic acid and furfural. The genes associated with stress responses of S. cerevisiae to single and mixed inhibitors were revealed. Specifically, we identified 184 consensus genes that were differentially regulated in response to the distinct inhibitor resistance between YC1 and S-C1. Bioinformatic analysis next revealed key transcription factors (TFs) that regulate these consensus genes. The top TFs identified, Sfp1p and Ace2p, were experimentally tested as overexpression targets for strain optimization. Overexpression of the SFP1 gene improved specific ethanol productivity by nearly four times, while overexpression of the ACE2 gene enhanced the rate by three times in the presence of acetic acid and furfural. Overexpression of SFP1 gene in the resistant strain YC1 further resulted in 42 % increase in ethanol productivity in the presence of acetic acid and furfural, suggesting the effect of Sfp1p in optimizing the yeast strain for improved tolerance to mixed fermentation inhibitor. CONCLUSIONS Transcriptional regulation underlying yeast resistance to acetic acid and furfural was determined. Two transcription factors, Sfp1p and Ace2p, were uncovered for the first time for their functions in improving yeast resistance to mixed fermentation inhibitors. The study demonstrated an omics-guided metabolic engineering framework, which could be developed as a promising strategy to improve complex microbial phenotypes.
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Affiliation(s)
- Yingying Chen
- />Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, 106E Cushing Hall of Engineering, Notre Dame, South Bend, IN 46556 USA
| | - Jiayuan Sheng
- />Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA USA
| | - Tao Jiang
- />Department of Civil and Environmental Engineering, University of Pittsburgh, Pittsburgh, PA USA
| | - Joseph Stevens
- />Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA USA
| | - Xueyang Feng
- />Department of Biological Systems Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA USA
| | - Na Wei
- />Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, 106E Cushing Hall of Engineering, Notre Dame, South Bend, IN 46556 USA
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Wang S, Cheng G, Joshua C, He Z, Sun X, Li R, Liu L, Yuan Q. Furfural tolerance and detoxification mechanism in Candida tropicalis. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:250. [PMID: 27891177 PMCID: PMC5116146 DOI: 10.1186/s13068-016-0668-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 11/15/2016] [Indexed: 05/02/2023]
Abstract
BACKGROUND Current biomass pretreatment by hydrothermal treatment (including acid hydrolysis, steam explosion, and high-temperature steaming) and ionic liquids generally generate inhibitors to the following fermentation process. Furfural is one of the typical inhibitors generated in hydrothermal treatment of biomass. Furfural could inhibit cell growth rate and decrease biofuel productivity of microbes. Candida tropicalis is a promising microbe for the production of biofuels and value-added chemicals using hemicellulose hydrolysate as carbon source. In this study, C. tropicalis showed a comparable ability of furfural tolerance during fermentation. We investigated the mechanism of C. tropicalis's robust tolerance to furfural and relevant metabolic responses to obtain more information for metabolic engineering of microbes for efficient lignocellulose fermentation. RESULTS Candida tropicalis showed comparable intrinsic tolerance to furfural and a fast rate of furfural detoxification. C. tropicalis's half maximal inhibitory concentration for furfural with xylose as the sole carbon source was 3.69 g/L, which was higher than that of most wild-type microbes reported in the literature to our knowledge. Even though furfural prolonged the lag phase of C. tropicalis, the final biomass in the groups treated with 1 g/L furfural was slightly greater than that in the control groups. By real-time PCR analysis, we found that the expression of ADH1 in C. tropicalis (ctADH1) was induced by furfural and repressed by ethanol after furfural depletion. The expression of ctADH1 could be regulated by both furfural and ethanol. After the disruption of gene ctADH1, we found that C. tropicalis's furfural tolerance was weakened. To further confirm the function of ctADH1 and enhance Escherichia coli's furfural tolerance, ctADH1 was overexpressed in E. coli BL21 (DE3). The rate of furfural degradation in E. coli BL21 (DE3) with pET-ADH1 (high-copy plasmid) and pCS-ADH1 (medium-copy plasmid) was increased by 1.59-fold and 1.28-fold, respectively. CONCLUSIONS Candida tropicalis was a robust strain with intrinsic tolerance to inhibitor furfural. The mechanism of furfural detoxification and metabolic responses were identified by multiple analyses. Alcohol dehydrogenase 1 was confirmed to be responsible for furfural detoxification. C. tropicalis showed a complex regulation system during furfural detoxification to minimize adverse effects caused by furfural. Furthermore, the mechanism we uncovered in this work was successfully applied to enhance E. coli's furfural tolerance by heterologous expression of ctADH1. The study provides deeper insights into strain modification for biofuel production by efficient lignocellulose fermentation.
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Affiliation(s)
- Shizeng Wang
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, West Room 314, Science and Technology Building, No. 15 North Third Ring East Road, Chaoyang District, Beijing, 100029 People’s Republic of China
| | - Gang Cheng
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, West Room 314, Science and Technology Building, No. 15 North Third Ring East Road, Chaoyang District, Beijing, 100029 People’s Republic of China
| | - Chijioke Joshua
- Deconstruction Division, Joint BioEnergy Institute, Emeryville, CA 94608 USA
| | - Zijun He
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, West Room 314, Science and Technology Building, No. 15 North Third Ring East Road, Chaoyang District, Beijing, 100029 People’s Republic of China
| | - Xinxiao Sun
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, West Room 314, Science and Technology Building, No. 15 North Third Ring East Road, Chaoyang District, Beijing, 100029 People’s Republic of China
| | - Ruimin Li
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, West Room 314, Science and Technology Building, No. 15 North Third Ring East Road, Chaoyang District, Beijing, 100029 People’s Republic of China
| | - Lexuan Liu
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, West Room 314, Science and Technology Building, No. 15 North Third Ring East Road, Chaoyang District, Beijing, 100029 People’s Republic of China
| | - Qipeng Yuan
- State Key Laboratory of Chemical Resource Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, West Room 314, Science and Technology Building, No. 15 North Third Ring East Road, Chaoyang District, Beijing, 100029 People’s Republic of China
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