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Huang S, Xue T, Wang Z, Ma Y, He X, Hong J, Zou S, Song H, Zhang M. Furfural-tolerant Zymomonas mobilis derived from error-prone PCR-based whole genome shuffling and their tolerant mechanism. Appl Microbiol Biotechnol 2018; 102:3337-3347. [PMID: 29464326 DOI: 10.1007/s00253-018-8817-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Revised: 01/22/2018] [Accepted: 01/27/2018] [Indexed: 11/29/2022]
Abstract
Furfural-tolerant strain is essential for the fermentative production of biofuels or chemicals from lignocellulosic biomass. In this study, Zymomonas mobilis CP4 was for the first time subjected to error-prone PCR-based whole genome shuffling, and the resulting mutants F211 and F27 that could tolerate 3 g/L furfural were obtained. The mutant F211 under various furfural stress conditions could rapidly grow when the furfural concentration reduced to 1 g/L. Meanwhile, the two mutants also showed higher tolerance to high concentration of glucose than the control strain CP4. Genome resequencing revealed that the F211 and F27 had 12 and 13 single-nucleotide polymorphisms. The activity assay demonstrated that the activity of NADH-dependent furfural reductase in mutant F211 and CP4 was all increased under furfural stress, and the activity peaked earlier in mutant than in control. Also, furfural level in the culture of F211 was also more rapidly decreased. These indicate that the increase in furfural tolerance of the mutants may be resulted from the enhanced NADH-dependent furfural reductase activity during early log phase, which could lead to an accelerated furfural detoxification process in mutants. In all, we obtained Z. mobilis mutants with enhanced furfural and high concentration of glucose tolerance, and provided valuable clues for the mechanism of furfural tolerance and strain development.
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Affiliation(s)
- Suzhen Huang
- R&D Center for Petrochemical Technology, Tianjin University, Weijin Road No. 92, Nankai District, Tianjin, 300072, China.,Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Tingli Xue
- R&D Center for Petrochemical Technology, Tianjin University, Weijin Road No. 92, Nankai District, Tianjin, 300072, China.,Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Zhiquan Wang
- R&D Center for Petrochemical Technology, Tianjin University, Weijin Road No. 92, Nankai District, Tianjin, 300072, China.,Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Yuanyuan Ma
- R&D Center for Petrochemical Technology, Tianjin University, Weijin Road No. 92, Nankai District, Tianjin, 300072, China. .,Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin, China.
| | - Xueting He
- R&D Center for Petrochemical Technology, Tianjin University, Weijin Road No. 92, Nankai District, Tianjin, 300072, China.,Department of Biochemical Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Jiefang Hong
- R&D Center for Petrochemical Technology, Tianjin University, Weijin Road No. 92, Nankai District, Tianjin, 300072, China
| | - Shaolan Zou
- R&D Center for Petrochemical Technology, Tianjin University, Weijin Road No. 92, Nankai District, Tianjin, 300072, China
| | - Hao Song
- Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin, China. .,Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.
| | - Minhua Zhang
- R&D Center for Petrochemical Technology, Tianjin University, Weijin Road No. 92, Nankai District, Tianjin, 300072, China.,Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin, China
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Interdependence of Primary Metabolism and Xenobiotic Mitigation Characterizes the Proteome of Bjerkandera adusta during Wood Decomposition. Appl Environ Microbiol 2018; 84:AEM.01401-17. [PMID: 29101201 PMCID: PMC5752865 DOI: 10.1128/aem.01401-17] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 10/31/2017] [Indexed: 12/29/2022] Open
Abstract
The aim of the current work was to identify key features of the fungal proteome involved in the active decay of beechwood blocks by the white rot fungus Bjerkandera adusta at 20°C and 24°C. A combination of protein and domain analyses ensured a high level of annotation, which revealed that while the variation in the proteins identified was high between replicates, there was a considerable degree of functional conservation between the two temperatures. Further analysis revealed differences in the pathways and processes employed by the fungus at the different temperatures, particularly in relation to nutrient acquisition and xenobiotic mitigation. Key features showing temperature-dependent variation in mechanisms for both lignocellulose decomposition and sugar utilization were found, alongside differences in the enzymes involved in mitigation against damage caused by toxic phenolic compounds and oxidative stress. IMPORTANCE This work was conducted using the wood decay fungus B. adusta, grown on solid wood blocks to closely mimic the natural environment, and gives greater insight into the proteome of an important environmental fungus during active decay. We show that a change in incubation temperature from 20°C to 24°C altered the protein profile. Proteomic studies in the field of white-rotting basidiomycetes have thus far been hampered by poor annotation of protein databases, with a large proportion of proteins simply with unknown function. This study was enhanced by extensive protein domain analysis, enabling a higher level of functional assignment and greater understanding of the proteome composition. This work revealed a strong interdependence of the primary process of nutrient acquisition and specialized metabolic processes for the detoxification of plant extractives and the phenolic breakdown products of lignocellulose.
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53
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Evaluation of Alkali-Pretreated Soybean Straw for Lignocellulosic Bioethanol Production. INT J POLYM SCI 2018. [DOI: 10.1155/2018/5241748] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Soybean straw is a renewable resource in agricultural residues that can be used for lignocellulosic bioethanol production. To enhance enzymatic digestibility and fermentability, the biomass was prepared with an alkali-thermal pretreatment (sodium hydroxide, 121°C, 60 min). The delignification yield was 34.1~53%, in proportion to the amount of sodium hydroxide, from 0.5 to 3.0 M. The lignin and hemicellulose contents of the pretreated biomass were reduced by the pretreatment process, whereas the proportion of cellulose was increased. Under optimal condition, the pretreated biomass consisted of 74.0±0.1% cellulose, 10.3±0.1% hemicellulose, and 10.1±0.6% lignin. During enzymatic saccharification using Cellic® CTec2 cellulase, 10% (w/v) of pretreated soybean straw was hydrolyzed completely and converted to 67.3±2.1 g/L glucose and 9.4±0.5 g/L xylose with a 90.9% yield efficiency. Simultaneous saccharification and fermentation of the pretreated biomass by Saccharomyces cerevisiae W303-1A produced 30.5±1.2 g/L ethanol in 0.5 L fermented medium containing 10% (w/v) pretreated biomass after 72 h. The ethanol productivity was 0.305 g ethanol/g dry biomass and 0.45 g ethanol/g glucose after fermentation, with a low concentration of organic acid metabolites. Also, 82% of fermentable sugar was used by the yeast for ethanol fermentation. These results show that the combination of alkaline pretreatment and biomass hydrolysate is useful for enhancing bioethanol productivity using delignified soybean straw.
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54
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Yoav S, Salame TM, Feldman D, Levinson D, Ioelovich M, Morag E, Yarden O, Bayer EA, Hadar Y. Effects of cre1 modification in the white-rot fungus Pleurotus ostreatus PC9: altering substrate preference during biological pretreatment. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:212. [PMID: 30065786 PMCID: PMC6062969 DOI: 10.1186/s13068-018-1209-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 07/18/2018] [Indexed: 05/16/2023]
Abstract
BACKGROUND During the process of bioethanol production, cellulose is hydrolyzed into its monomeric soluble units. For efficient hydrolysis, a chemical and/or mechanical pretreatment step is required. Such pretreatment is designed to increase enzymatic digestibility of the cellulose chains inter alia by de-crystallization of the cellulose chains and by removing barriers, such as lignin from the plant cell wall. Biological pretreatment, in which lignin is decomposed or modified by white-rot fungi, has also been considered. One disadvantage in biological pretreatment, however, is the consumption of the cellulose by the fungus. Thus, fungal species that attack lignin with only minimal cellulose loss are advantageous. The secretomes of white-rot fungi contain carbohydrate-active enzymes (CAZymes) including lignin-modifying enzymes. Thus, modification of secretome composition can alter the ratio of lignin/cellulose degradation. RESULTS Pleurotus ostreatus PC9 was genetically modified to either overexpress or eliminate (by gene replacement) the transcriptional regulator CRE1, known to act as a repressor in the process of carbon catabolite repression. The cre1-overexpressing transformant demonstrated lower secreted cellulolytic activity and slightly increased selectivity (based on the chemical composition of pretreated wheat straw), whereas the knockout transformant demonstrated increased cellulolytic activity and significantly reduced residual cellulose, thereby displaying lower selectivity. Pretreatment of wheat straw using the wild-type PC9 resulted in 2.8-fold higher yields of soluble sugar compared to untreated wheat straw. The overexpression transformant showed similar yields (2.6-fold), but the knockout transformant exhibited lower yields (1.2-fold) of soluble sugar. Based on proteomic secretome analysis, production of numerous CAZymes was affected by modification of the expression level of cre1. CONCLUSIONS The gene cre1 functions as a regulator for expression of fungal CAZymes active against plant cell wall lignocelluloses, hence altering the substrate preference of the fungi tested. While the cre1 knockout resulted in a less efficient biological pretreatment, i.e., less saccharification of the treated biomass, the converse manipulation of cre1 (overexpression) failed to improve efficiency. Despite the inverse nature of the two genetic alterations, the expected "mirror image" (i.e., opposite regulatory response) was not observed, indicating that the secretion level of CAZymes, was not exclusively dependent on CRE1 activity.
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Affiliation(s)
- Shahar Yoav
- Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100 Israel
| | - Tomer M. Salame
- Flow Cytometry Unit, Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, 76100 Israel
| | - Daria Feldman
- Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100 Israel
| | - Dana Levinson
- Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100 Israel
| | | | - Ely Morag
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, 76100 Israel
| | - Oded Yarden
- Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100 Israel
| | - Edward A. Bayer
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, 76100 Israel
| | - Yitzhak Hadar
- Department of Plant Pathology and Microbiology, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100 Israel
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55
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Gaur N, Narasimhulu K, Y P. Biochemical and kinetic characterization of laccase and manganese peroxidase from novelKlebsiella pneumoniaestrains and their application in bioethanol production. RSC Adv 2018; 8:15044-15055. [PMID: 35541315 PMCID: PMC9080042 DOI: 10.1039/c8ra01204k] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/15/2018] [Indexed: 11/21/2022] Open
Abstract
Laccase (lac) and manganese peroxidase (MnP) enzymes from the novel Klebsiella pneumoniae isolates, grown on lignin basic media (LBM) were purified by 80% ammonium sulphate fractionation, dialysis and DEAE-sepharose column chromatography. The optimum temperatures for laccase production were 60 °C, 50 °C and 50 °C and for MnP production were 50 °C, 70 °C and 60 °C from NITW715076_2, NITW715076_1 and NITW715076 isolates, respectively. The optimal pH for production was found to be 5 for production of both the enzymes from all the isolates. 2.8–3.5 fold enzyme purification was achieved retaining around 60–70% of the initial activity. SDS-PAGE revealed the molecular mass of laccase and MnP to be 66 kDa and 48 kDa, respectively. The substrate ABTS and MnSO4 exhibited more specificity towards NITW715075_2 derived laccase and MnP (lac: Km = 0.38 mM, Vmax = 71.42 U ml−1; MnP: Km = 0.17 mM, Vmax = 106.38 U ml−1) compared to NITW715076_1 (lac: Km = 3.97 mM, Vmax = 148.8 U ml−1; MnP: Km = 0.90 mM, Vmax = 114.67 U ml−1) and NITW715076 (lac: Km = 0.46 mM, Vmax = 23.42 U ml−1; MnP: Km = 0.19 mM, Vmax = 108.10 U ml−1) derived. l-Cysteine and sodium azide imposed a strong inhibitory effect on the activities of both the enzymes. EDTA inhibited laccase and MnP activity at higher concentration. SDS strongly inhibited activity while for MnP it showed less inhibitory effect. The enzymes were employed for ethanol production from rice and wheat bran biomass which showed 39.29% improved production compared to control. After evaluating the applicability of these enzymes it can be suggested that the ligninolytic enzyme of Klebsiella pneumoniae isolates could be effectively employed in enhanced ethanol production and could be explored for other putative applications. Upto 3 fold purified laccase and MnP from novel Klebsiella isolates, mediated ethanol production from rice and wheat bran substrates lead to almost 40% improvement in production profile.![]()
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Affiliation(s)
- Nisha Gaur
- Department of Biotechnology
- National Institute of Technology Warangal
- India
| | | | - Pydisetty Y
- Department of Chemical Engineering
- National Institute of Technology Warangal
- India
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56
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Yee KL, Jansen LE, Lajoie CA, Penner MH, Morse L, Kelly CJ. Furfural and 5-hydroxymethyl-furfural degradation using recombinant manganese peroxidase. Enzyme Microb Technol 2018; 108:59-65. [DOI: 10.1016/j.enzmictec.2017.08.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 07/07/2017] [Accepted: 08/28/2017] [Indexed: 02/03/2023]
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57
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Scholz SA, Graves I, Minty JJ, Lin XN. Production of cellulosic organic acids via synthetic fungal consortia. Biotechnol Bioeng 2017; 115:1096-1100. [PMID: 29205274 DOI: 10.1002/bit.26509] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 11/16/2017] [Accepted: 11/27/2017] [Indexed: 11/10/2022]
Abstract
Consolidated bioprocessing (CBP) is a potential breakthrough technology for reducing costs of biochemical production from lignocellulosic biomass. Production of cellulase enzymes, saccharification of lignocellulose, and conversion of the resulting sugars into a chemical of interest occur simultaneously within a single bioreactor. In this study, synthetic fungal consortia composed of the cellulolytic fungus Trichoderma reesei and the production specialist Rhizopus delemar demonstrated conversion of microcrystalline cellulose (MCC) and alkaline pre-treated corn stover (CS) to fumaric acid in a fully consolidated manner without addition of cellulase enzymes or expensive supplements such as yeast extract. A titer of 6.87 g/L of fumaric acid, representing 0.17 w/w yield, were produced from 40 g/L MCC with a productivity of 31.8 mg/L/hr. In addition, lactic acid was produced from MCC using a fungal consortium with Rhizopus oryzae as the production specialist. These results are proof-of-concept demonstration of engineering synthetic microbial consortia for CBP production of naturally occurring biomolecules.
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Affiliation(s)
- Scott A Scholz
- Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, Michigan
| | - Ian Graves
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Jeremy J Minty
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Xiaoxia N Lin
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan.,Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
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58
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Endophytic Fungi as Pretreatment to Enhance Enzymatic Hydrolysis of Olive Tree Pruning. BIOMED RESEARCH INTERNATIONAL 2017; 2017:9727581. [PMID: 29250553 PMCID: PMC5698607 DOI: 10.1155/2017/9727581] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/28/2017] [Accepted: 10/18/2017] [Indexed: 11/17/2022]
Abstract
Olive tree pruning, as one of the most abundant lignocellulosic residues in Mediterranean countries, has been evaluated as a source of sugars for fuel and chemicals production. A mild acid pretreatment has been combined with a fungal pretreatment using either two endophytes (Ulocladium sp. and Hormonema sp.) or a saprophyte (Trametes sp. I-62). The use of endophytes is based on the important role that some of them play during the initial stages of wood decomposition. Without acid treatment, fungal pretreatment with Ulocladium sp. provided a nonsignificant enhancement of 4.6% in glucose digestibility, compared to control. When a mild acid hydrolysis was carried out after fungal pretreatments, significant increases in glucose digestibility from 4.9% to 12.0% (compared to control without fungi) were observed for all fungal pretreatments, with maximum values yielded by Hormonema sp. However, despite the observed digestibility boost, the total sugar yields (taking into account solid yield) were not significantly increased by the pretreatments. Nevertheless, based on these preliminary improvements in digestibility, this work proves the potential of endophytic fungi to boost the production of sugar from olive tree pruning, which would add an extra value to the bioeconomy of olive crops.
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De La Torre M, Martín-Sampedro R, Fillat Ú, Eugenio ME, Blánquez A, Hernández M, Arias ME, Ibarra D. Comparison of the efficiency of bacterial and fungal laccases in delignification and detoxification of steam-pretreated lignocellulosic biomass for bioethanol production. ACTA ACUST UNITED AC 2017; 44:1561-1573. [DOI: 10.1007/s10295-017-1977-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 09/05/2017] [Indexed: 11/30/2022]
Abstract
Abstract
This study evaluates the potential of a bacterial laccase from Streptomyces ipomoeae (SilA) for delignification and detoxification of steam-exploded wheat straw, in comparison with a commercial fungal laccase from Trametes villosa. When alkali extraction followed by SilA laccase treatment was applied to the water insoluble solids fraction, a slight reduction in lignin content was detected, and after a saccharification step, an increase in both glucose and xylose production (16 and 6%, respectively) was observed. These effects were not produced with T. villosa laccase. Concerning to the fermentation process, the treatment of the steam-exploded whole slurry with both laccases produced a decrease in the phenol content by up to 35 and 71% with bacterial and fungal laccases, respectively. The phenols reduction resulted in an improved performance of Saccharomyces cerevisiae during a simultaneous saccharification and fermentation (SSF) process, improving ethanol production rate. This enhancement was more marked with a presaccharification step prior to the SSF process.
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Affiliation(s)
- María De La Torre
- 0000 0004 1937 0239 grid.7159.a Departamento de Biomedicina y Biotecnología Universidad de Alcalá Autovía A-2, Km 33.600 28805 Alcalá De Henares Madrid Spain
| | | | - Úrsula Fillat
- Forestry Products Department INIA-CIFOR Ctra. de La Coruña Km 7.5 28040 Madrid Spain
| | - María E Eugenio
- Forestry Products Department INIA-CIFOR Ctra. de La Coruña Km 7.5 28040 Madrid Spain
| | - Alba Blánquez
- 0000 0004 1937 0239 grid.7159.a Departamento de Biomedicina y Biotecnología Universidad de Alcalá Autovía A-2, Km 33.600 28805 Alcalá De Henares Madrid Spain
| | - Manuel Hernández
- 0000 0004 1937 0239 grid.7159.a Departamento de Biomedicina y Biotecnología Universidad de Alcalá Autovía A-2, Km 33.600 28805 Alcalá De Henares Madrid Spain
| | - María E Arias
- 0000 0004 1937 0239 grid.7159.a Departamento de Biomedicina y Biotecnología Universidad de Alcalá Autovía A-2, Km 33.600 28805 Alcalá De Henares Madrid Spain
| | - David Ibarra
- Forestry Products Department INIA-CIFOR Ctra. de La Coruña Km 7.5 28040 Madrid Spain
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60
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Brethauer S, Robert Lawrence S, Michael Hans-Peter S. Enhanced simultaneous saccharification and fermentation of pretreated beech wood by in situ treatment with the white rot fungus Irpex lacteus in a membrane aerated biofilm reactor. BIORESOURCE TECHNOLOGY 2017; 237:135-138. [PMID: 28400170 DOI: 10.1016/j.biortech.2017.03.050] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 03/03/2017] [Accepted: 03/07/2017] [Indexed: 06/07/2023]
Abstract
The aim of the present study was to investigate the combination of steam pretreatment and biological treatment with lignin degrading fungal strains in order to enable efficient bioprocessing of beech wood to ethanol. In a sequential process of steam and fungal pretreatment followed by enzymatic hydrolysis, Irpex lacteus almost doubled the glucose yield for mildly pretreated beech wood, but could not improve yields for more severely pretreated substrates. However, when simultaneous saccharification and fermentation is combined with in situ I. lacteus treatment, which is enabled by the application of a membrane aerated biofilm reactor, ethanol yields of optimally steam pretreated beech could be improved from 65 to 80%. Generally, in situ fungal treatment during bioprocessing of lignocellulose is an interesting method to harness the versatile abilities of white rot fungi.
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Affiliation(s)
- Simone Brethauer
- Bern University of Applied Sciences, School of Agricultural, Forest and Food Sciences, Länggasse 85, CH-3052 Zollikofen, Switzerland
| | - Shahab Robert Lawrence
- Bern University of Applied Sciences, School of Agricultural, Forest and Food Sciences, Länggasse 85, CH-3052 Zollikofen, Switzerland; Laboratory of Sustainable and Catalytic Processing, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Studer Michael Hans-Peter
- Bern University of Applied Sciences, School of Agricultural, Forest and Food Sciences, Länggasse 85, CH-3052 Zollikofen, Switzerland.
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Daphnia magna demonstrated sufficient sensitivity in techno-economic optimization of lignocellulose bioethanol production. 3 Biotech 2017; 7:162. [PMID: 28660451 DOI: 10.1007/s13205-017-0839-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 04/18/2017] [Indexed: 10/19/2022] Open
Abstract
Notable progress has been achieved in the past two decades regarding production of different enzymatic mixtures for hydrolysis of the lignocellulose matrix. Nevertheless, the hydrolysing mixtures remain slow and require tempering, which results in high-energy demands and bad financial results. Use of acids or alkali at a very high temperature and pressure accelerates the process more than ten times wherein the energy requirements are approximately equal. However, these elevated reaction conditions might cause the breakdown of complex lignin formula into substances that have the potential to inhibit subsequent fermentation processes. Formation of these breakdown products may be prevented by selecting the optimum process parameters, but their acquisition requires either a large number of expensive analytical techniques or equally large amounts of slow fermentation tests. An inexpensive and time saving alternative that is based on the sensitivity of chosen organisms to these inhibitors was designed and financially assessed. It was confirmed that the method is technically feasible and economically viable with significant potential to reduce the bioethanol production cost.
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62
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Delignification and enhanced gas release from soil containing lignocellulose by treatment with bacterial lignin degraders. J Appl Microbiol 2017; 123:159-171. [DOI: 10.1111/jam.13470] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/04/2017] [Accepted: 04/05/2017] [Indexed: 01/14/2023]
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63
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Laccases as a Potential Tool for the Efficient Conversion of Lignocellulosic Biomass: A Review. FERMENTATION-BASEL 2017. [DOI: 10.3390/fermentation3020017] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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64
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A Sequential Steam Explosion and Reactive Extrusion Pretreatment for Lignocellulosic Biomass Conversion within a Fermentation-Based Biorefinery Perspective. FERMENTATION-BASEL 2017. [DOI: 10.3390/fermentation3020015] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The present work evaluates a two-step pretreatment process based on steam explosion and extrusion technologies for the optimal fractionation of lignocellulosic biomass. Two-step pretreatment of barley straw resulted in overall glucan, hemicellulose and lignin recovery yields of 84%, 91% and 87%, respectively. Precipitation of the collected lignin-rich liquid fraction yielded a solid residue with high lignin content, offering possibilities for subsequent applications. Moreover, hydrolysability tests showed almost complete saccharification of the pretreated solid residue, which when combined with the low concentration of the generated inhibitory compounds, is representative of a good pretreatment approach. Scheffersomyces stipitis was capable of fermenting all of the glucose and xylose from the non-diluted hemicellulose fraction, resulting in an ethanol concentration of 17.5 g/L with 0.34 g/g yields. Similarly, Saccharomyces cerevisiae produced about 4% (v/v) ethanol concentration with 0.40 g/g yields, during simultaneous saccharification and fermentation (SSF) of the two-step pretreated solid residue at 10% (w/w) consistency. These results increased the overall conversion yields from a one-step steam explosion pretreatment by 1.4-fold, showing the effectiveness of including an extrusion step to enhance overall biomass fractionation and carbohydrates conversion via microbial fermentation processes.
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65
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Moreno AD, Alvira P, Ibarra D, Tomás-Pejó E. Production of Ethanol from Lignocellulosic Biomass. PRODUCTION OF PLATFORM CHEMICALS FROM SUSTAINABLE RESOURCES 2017. [DOI: 10.1007/978-981-10-4172-3_12] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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66
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Gao Y, Zheng L, Li JJ, Du Y. Insight into the impact of two structural calcium ions on the properties of Pleurotus eryngii versatile ligninolytic peroxidase. Arch Biochem Biophys 2016; 612:9-16. [PMID: 27720685 DOI: 10.1016/j.abb.2016.10.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 09/14/2016] [Accepted: 10/04/2016] [Indexed: 11/16/2022]
Abstract
Two structural Ca2+ (proximal and distal) is known to be important for ligninolytic peroxidases. However, few studies toward impact of residues involved in two Ca2+ on properties of ligninolytic peroxidases have been done, especially the proximal one. In this study, mutants of nine residues involved in liganding two Ca2+ of Pleurotus eryngii versatile peroxidase (VP) were investigated. Most mutants almost completely lost activities, except the mutants of proximal Ca2+ - S170A and V192T. In comparison with WT (wild type), optimal pH values of S170A, S170D, and V192T shifted from pH 3.0 to pH 3.5. The order of thermal and pH stabilities of WT, V192T, S170A, and S170D is similar to that of their specific activities: WT > V192T > S170A > S170D. The CD (circular dichroism) results of WT and several mutants indicated that mutations had some effects on secondary structures. For the first time, it was observed that the thermostability of ligninolytic peroxidases is related with proximal Ca2+ too, and the mutant containing distal Ca2+ only was obtained. Our results clearly demonstrated that enzymatic activities, pH and thermal stabilities, Ca2+content, and secondary structures of VP have close relationship with the residues involved in two structural Ca2+.
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Affiliation(s)
- Yu Gao
- Department of Microbiology and Parasitology, China Medical University, No.77 Puhe Road, Shenyang 110122, Liaoning Province, China
| | - Lanyan Zheng
- Department of Microbiology and Parasitology, China Medical University, No.77 Puhe Road, Shenyang 110122, Liaoning Province, China.
| | - Jian-Jun Li
- National Key Laboratory of Biochemical Engineering, National Engineering Research Center for Biotechnology (Beijing), Key Laboratory of Biopharmaceutical Production & Formulation Engineering, PLA, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 North 2nd Street, Beijing 100190, China.
| | - Yuguang Du
- National Key Laboratory of Biochemical Engineering, National Engineering Research Center for Biotechnology (Beijing), Key Laboratory of Biopharmaceutical Production & Formulation Engineering, PLA, Institute of Process Engineering, Chinese Academy of Sciences, No. 1 North 2nd Street, Beijing 100190, China.
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67
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Liguori R, Faraco V. Biological processes for advancing lignocellulosic waste biorefinery by advocating circular economy. BIORESOURCE TECHNOLOGY 2016; 215:13-20. [PMID: 27131870 DOI: 10.1016/j.biortech.2016.04.054] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/10/2016] [Accepted: 04/11/2016] [Indexed: 05/21/2023]
Abstract
The actualization of a circular economy through the use of lignocellulosic wastes as renewable resources can lead to reduce the dependence from fossil-based resources and contribute to a sustainable waste management. The integrated biorefineries, exploiting the overall lignocellulosic waste components to generate fuels, chemicals and energy, are the pillar of the circular economy. The biological treatment is receiving great attention for the biorefinery development since it is considered an eco-friendly alternative to the physico-chemical strategies to increase the biobased product recovery from wastes and improve saccharification and fermentation yields. This paper reviews the last advances in the biological treatments aimed at upgrading lignocellulosic wastes, implementing the biorefinery concept and advocating circular economy.
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Affiliation(s)
- Rossana Liguori
- Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, via Cintia, 4, 80126 Naples, Italy
| | - Vincenza Faraco
- Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, via Cintia, 4, 80126 Naples, Italy; European Center "Europe Direct LUPT", Italy; Interdepartmental Center "R. d'Ambrosio, LUPT", Italy.
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68
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Wang J, Suzuki T, Dohra H, Takigami S, Kako H, Soga A, Kamei I, Mori T, Kawagishi H, Hirai H. Analysis of ethanol fermentation mechanism of ethanol producing white-rot fungus Phlebia sp. MG-60 by RNA-seq. BMC Genomics 2016; 17:616. [PMID: 27515927 PMCID: PMC4982002 DOI: 10.1186/s12864-016-2977-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 07/28/2016] [Indexed: 08/25/2023] Open
Abstract
Background The white-rot fungus Phlebia sp. MG-60 shows valuable properties such as high ethanol yield from several lignocellulosic materials, although white-rot fungi commonly degrade woody components to CO2 and H2O. In order to identify genes involved in ethanol production by Phlebia sp. MG-60, we compared genes differentially expressed by the ethanol producing fungus Phlebia sp. MG-60 and the model white-rot fungus Phanerochaete chrysosporium under ethanol fermenting and non-fermenting conditions using next-generation sequencing technologies. Results mRNAs from mycelia of Phlebia sp. MG-60 and P. chrysosporium under fermenting and non-fermenting conditions were sequenced using the MiSeq system. To detect differentially expressed genes, expression levels were measured in fragments per kilobase of exon per million mapped reads (FPKM). Differentially expressed genes were annotated using BLAST searches, Gene Ontology classifications, and KEGG pathway analysis. Functional analyses of differentially expressed genes revealed that genes involved in glucose uptake, glycolysis, and ethanol synthesis were widely upregulated in Phlebia sp. MG-60 under fermenting conditions. Conclusions In this study, we provided novel transcriptomic information on Phlebia sp. MG-60, and these RNA-seq data were useful in targeting genes involved in ethanol production for future genetic engineering. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2977-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jianqiao Wang
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Tomohiro Suzuki
- Center for Bioscience Research and Education, Utsunomiya University, 350 Mine-machi, Utsunomiya, 321-8505, Japan
| | - Hideo Dohra
- Institute for Genetic Research and Biotechnology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan.,Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Shoko Takigami
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Hiroko Kako
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Ayumi Soga
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Ichiro Kamei
- Faculty of Agriculture, University of Miyazaki, 1-1 Gakuen-kibanadai-nishi, Miyazaki, 889-2192, Japan
| | - Toshio Mori
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Hirokazu Kawagishi
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan.,Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan.,Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Hirofumi Hirai
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan. .,Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan.
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69
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Rosnow JJ, Anderson LN, Nair RN, Baker ES, Wright AT. Profiling microbial lignocellulose degradation and utilization by emergent omics technologies. Crit Rev Biotechnol 2016; 37:626-640. [PMID: 27439855 DOI: 10.1080/07388551.2016.1209158] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The use of plant materials to generate renewable biofuels and other high-value chemicals is the sustainable and preferable option, but will require considerable improvements to increase the rate and efficiency of lignocellulose depolymerization. This review highlights novel and emerging technologies that are being developed and deployed to characterize the process of lignocellulose degradation. The review will also illustrate how microbial communities deconstruct and metabolize lignocellulose by identifying the necessary genes and enzyme activities along with the reaction products. These technologies include multi-omic measurements, cell sorting and isolation, nuclear magnetic resonance spectroscopy (NMR), activity-based protein profiling, and direct measurement of enzyme activity. The recalcitrant nature of lignocellulose necessitates the need to characterize the methods microbes employ to deconstruct lignocellulose to inform new strategies on how to greatly improve biofuel conversion processes. New technologies are yielding important insights into microbial functions and strategies employed to degrade lignocellulose, providing a mechanistic blueprint in order to advance biofuel production.
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Affiliation(s)
- Joshua J Rosnow
- a Biological Sciences Division , Pacific Northwest National Laboratory , Richland , WA , USA
| | - Lindsey N Anderson
- a Biological Sciences Division , Pacific Northwest National Laboratory , Richland , WA , USA
| | - Reji N Nair
- a Biological Sciences Division , Pacific Northwest National Laboratory , Richland , WA , USA
| | - Erin S Baker
- a Biological Sciences Division , Pacific Northwest National Laboratory , Richland , WA , USA
| | - Aaron T Wright
- a Biological Sciences Division , Pacific Northwest National Laboratory , Richland , WA , USA
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70
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Lambertz C, Ece S, Fischer R, Commandeur U. Progress and obstacles in the production and application of recombinant lignin-degrading peroxidases. Bioengineered 2016; 7:145-54. [PMID: 27295524 DOI: 10.1080/21655979.2016.1191705] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Lignin is 1 of the 3 major components of lignocellulose. Its polymeric structure includes aromatic subunits that can be converted into high-value-added products, but this potential cannot yet been fully exploited because lignin is highly recalcitrant to degradation. Different approaches for the depolymerization of lignin have been tested, including pyrolysis, chemical oxidation, and hydrolysis under supercritical conditions. An additional strategy is the use of lignin-degrading enzymes, which imitates the natural degradation process. A versatile set of enzymes for lignin degradation has been identified, and research has focused on the production of recombinant enzymes in sufficient amounts to characterize their structure and reaction mechanisms. Enzymes have been analyzed individually and in combinations using artificial substrates, lignin model compounds, lignin and lignocellulose. Here we consider progress in the production of recombinant lignin-degrading peroxidases, the advantages and disadvantages of different expression hosts, and obstacles that must be overcome before such enzymes can be characterized and used for the industrial processing of lignin.
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Affiliation(s)
- Camilla Lambertz
- a Institute for Molecular Biotechnology, RWTH Aachen University , Aachen , Germany
| | - Selin Ece
- a Institute for Molecular Biotechnology, RWTH Aachen University , Aachen , Germany
| | - Rainer Fischer
- a Institute for Molecular Biotechnology, RWTH Aachen University , Aachen , Germany.,b Fraunhofer Institute for Molecular Biology and Applied Ecology , Aachen , Germany
| | - Ulrich Commandeur
- a Institute for Molecular Biotechnology, RWTH Aachen University , Aachen , Germany
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71
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A Bacterial Laccase for Enhancing Saccharification and Ethanol Fermentation of Steam-Pretreated Biomass. FERMENTATION-BASEL 2016. [DOI: 10.3390/fermentation2020011] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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72
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Comparative analysis of lignin peroxidase and manganese peroxidase activity on coniferous and deciduous wood using ToF-SIMS. Appl Microbiol Biotechnol 2016; 100:8013-20. [DOI: 10.1007/s00253-016-7560-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 04/10/2016] [Accepted: 04/16/2016] [Indexed: 11/30/2022]
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73
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Taha M, Foda M, Shahsavari E, Aburto-Medina A, Adetutu E, Ball A. Commercial feasibility of lignocellulose biodegradation: possibilities and challenges. Curr Opin Biotechnol 2016; 38:190-7. [DOI: 10.1016/j.copbio.2016.02.012] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/28/2016] [Accepted: 02/06/2016] [Indexed: 10/22/2022]
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74
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Putro JN, Soetaredjo FE, Lin SY, Ju YH, Ismadji S. Pretreatment and conversion of lignocellulose biomass into valuable chemicals. RSC Adv 2016. [DOI: 10.1039/c6ra09851g] [Citation(s) in RCA: 148] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Lignocellulose biomass can be utilized in many sectors of industry such as energy, chemical, and transportation. However, pretreatment is needed to break down the intricate bonding before converting it into wanted product.
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Affiliation(s)
- Jindrayani Nyoo Putro
- Department of Chemical Engineering
- National Taiwan University of Science and Technology
- Taipei 10607
- Taiwan
| | - Felycia Edi Soetaredjo
- Department of Chemical Engineering
- Widya Mandala Surabaya Catholic University
- Surabaya 60114
- Indonesia
| | - Shi-Yow Lin
- Department of Chemical Engineering
- National Taiwan University of Science and Technology
- Taipei 10607
- Taiwan
| | - Yi-Hsu Ju
- Department of Chemical Engineering
- National Taiwan University of Science and Technology
- Taipei 10607
- Taiwan
| | - Suryadi Ismadji
- Department of Chemical Engineering
- Widya Mandala Surabaya Catholic University
- Surabaya 60114
- Indonesia
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75
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Guerriero G, Hausman J, Strauss J, Ertan H, Siddiqui KS. Lignocellulosic bioma
ss
: Biosynthesis, degradation, and industrial utilization. Eng Life Sci 2015. [DOI: 10.1002/elsc.201400196] [Citation(s) in RCA: 127] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Affiliation(s)
- Gea Guerriero
- Environmental Research and Innovation (ERIN) Luxembourg Institute of Science and Technology (LIST) Esch/Alzette Luxembourg
| | - Jean‐Francois Hausman
- Environmental Research and Innovation (ERIN) Luxembourg Institute of Science and Technology (LIST) Esch/Alzette Luxembourg
| | - Joseph Strauss
- Department of Applied Genetics and Cell Biology Fungal Genetics and Genomics Unit University of Natural Resources and Life Sciences Vienna (BOKU) University and Research Center Campus Tulln‐Technopol Tulln/Donau Austria
- Health and Environment Department Austrian Institute of Technology GmbH ‐ AIT University and Research Center Campus Tulln‐Technopol Tulln/Donau Austria
| | - Haluk Ertan
- School of Biotechnology and Biomolecular Sciences The University of New South Wales Sydney Australia
- Department of Molecular Biology and Genetics Istanbul University Istanbul Turkey
| | - Khawar Sohail Siddiqui
- Life Sciences Department King Fahd University of Petroleum and Minerals (KFUPM) Dhahran Kingdom of Saudi Arabia
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Forootanfar H, Faramarzi MA. Insights into laccase producing organisms, fermentation states, purification strategies, and biotechnological applications. Biotechnol Prog 2015; 31:1443-63. [DOI: 10.1002/btpr.2173] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/30/2015] [Indexed: 12/07/2022]
Affiliation(s)
- Hamid Forootanfar
- Dept. of Pharmaceutical Biotechnology, Faculty of Pharmacy; Kerman University of Medical Sciences; Kerman Iran
| | - Mohammad Ali Faramarzi
- Dept. of Pharmaceutical Biotechnology, Faculty of Pharmacy & Biotechnology Research Center; Tehran University of Medical Sciences; Tehran 1417614411 Iran
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Kim SY, Kim KH, Im CH, Ali A, Lee CY, Kong WS, Ryu JS. Identification of degenerate nuclei and development of a SCAR marker for Flammulina velutipes. PLoS One 2014; 9:e107207. [PMID: 25221949 PMCID: PMC4164608 DOI: 10.1371/journal.pone.0107207] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 08/08/2014] [Indexed: 11/18/2022] Open
Abstract
Flammulina velutipes is one of the major edible mushrooms in the world. Recently, abnormalities that have a negative impact on crop production have been reported in this mushroom. These symptoms include slow vegetative growth, a compact mycelial mat, and few or even no fruiting bodies. The morphologies and fruiting capabilities of monokaryons of wild-type and degenerate strains that arose through arthrospore formation were investigated through test crossing. Only one monokaryotic group of the degenerate strains and its hybrid strains showed abnormal phenotypes. Because the monokaryotic arthrospore has the same nucleus as the parent strain, these results indicated that only one aberrant nucleus of the two nuclei in the degenerate strain was responsible for the degeneracy. A sequence-characterized amplified region marker that is linked to the degenerate monokaryon was identified based on a polymorphic sequence that was generated using random primers. Comparative analyses revealed the presence of a degenerate-specific genomic region in a telomere, which arose via the transfer of a genomic fragment harboring a putative helicase gene. Our findings have narrowed down the potential molecular targets responsible for this phenotype for future studies and have provided a marker for the detection of degenerate strains.
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Affiliation(s)
- Sun Young Kim
- Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea
| | - Kyung-Hee Kim
- Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea
| | - Chak Han Im
- Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea
| | - Asjad Ali
- Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea
| | | | - Won-Sik Kong
- Mushroom Research Division, National Institute of Horticultural and Herbal Science, Rural Development Administration, Eumsung, Republic of Korea
| | - Jae-San Ryu
- Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea
- * E-mail:
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