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Igwebuike CM, Awad S, Andrès Y. Renewable Energy Potential: Second-Generation Biomass as Feedstock for Bioethanol Production. Molecules 2024; 29:1619. [PMID: 38611898 PMCID: PMC11013350 DOI: 10.3390/molecules29071619] [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: 03/07/2024] [Revised: 03/25/2024] [Accepted: 03/30/2024] [Indexed: 04/14/2024] Open
Abstract
Biofuels are clean and renewable energy resources gaining increased attention as a potential replacement for non-renewable petroleum-based fuels. They are derived from biomass that could either be animal-based or belong to any of the three generations of plant biomass (agricultural crops, lignocellulosic materials, or algae). Over 130 studies including experimental research, case studies, literature reviews, and website publications related to bioethanol production were evaluated; different methods and techniques have been tested by scientists and researchers in this field, and the most optimal conditions have been adopted for the generation of biofuels from biomass. This has ultimately led to a subsequent scale-up of procedures and the establishment of pilot, demo, and large-scale plants/biorefineries in some regions of the world. Nevertheless, there are still challenges associated with the production of bioethanol from lignocellulosic biomass, such as recalcitrance of the cell wall, multiple pretreatment steps, prolonged hydrolysis time, degradation product formation, cost, etc., which have impeded the implementation of its large-scale production, which needs to be addressed. This review gives an overview of biomass and bioenergy, the structure and composition of lignocellulosic biomass, biofuel classification, bioethanol as an energy source, bioethanol production processes, different pretreatment and hydrolysis techniques, inhibitory product formation, fermentation strategies/process, the microorganisms used for fermentation, distillation, legislation in support of advanced biofuel, and industrial projects on advanced bioethanol. The ultimate objective is still to find the best conditions and technology possible to sustainably and inexpensively produce a high bioethanol yield.
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Affiliation(s)
| | - Sary Awad
- IMT Atlantique, GEPEA, UMR CNRS 6144, 4 Rue Alfred Kastler, F-44000 Nantes, France; (C.M.I.); (Y.A.)
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Jia Y, Maitra S, Singh V. Chemical-free production of multiple high-value bioproducts from metabolically engineered transgenic sugarcane 'oilcane' bagasse and their recovery using nanofiltration. BIORESOURCE TECHNOLOGY 2023; 371:128630. [PMID: 36657588 DOI: 10.1016/j.biortech.2023.128630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
Bioenergy crops have potential for being a sustainable and renewable feedstock for biofuels and various value-added bioproducts. The study utilizes recently developed transgenic sugarcane ('oilcane') bagasse for chemical-free coproduction of high-value bioproducts, i.e., furfurals, HMF, acetic acid, cellulosic sugars, and vegetative lipids. Hydrothermal pretreatment was optimized at 210 °C for 5 min to coproduce 6.91%, 2.67%, 5.07%, 2.42% and 37.82% (w/w) furfurals, HMF, acetic acid, vegetative lipids, and cellulosic sugars, respectively from lignocellulosic biomass. Additionally, nanofiltration system in-series was successfully established to recover sugars, furfurals, HMF, and acetic acid from the pretreatment liquor. 1st nanofiltration with Duracid NF membrane rejected ∼99% sugars. Concentrated sugars with significantly reduced inhibitory products were obtained in retentate for fermentation. 2nd nanofiltration with NF90 membrane used permeate of 1st nanofiltration as feed and rejected ∼ 86% furfurals. The work demonstrates the feasibility of coproducing and recovering multiple biochemicals from lignocellulosic biomass.
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Affiliation(s)
- Yuyao Jia
- Agricultural and Biological Engineering, University of Illinois, 1304 W. Pennsylvania Avenue, Urbana, IL 61801, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois, 1206 W. Gregory Drive, Urbana, IL 61801, USA
| | - Shraddha Maitra
- Agricultural and Biological Engineering, University of Illinois, 1304 W. Pennsylvania Avenue, Urbana, IL 61801, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois, 1206 W. Gregory Drive, Urbana, IL 61801, USA
| | - Vijay Singh
- Agricultural and Biological Engineering, University of Illinois, 1304 W. Pennsylvania Avenue, Urbana, IL 61801, USA; DOE Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois, 1206 W. Gregory Drive, Urbana, IL 61801, USA.
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Atatoprak T, Amorim MM, Ribeiro T, Pintado M, Madureira AR. Grape stalk valorization for fermentation purposes. FOOD CHEMISTRY. MOLECULAR SCIENCES 2022; 4:100067. [PMID: 35415689 PMCID: PMC8991497 DOI: 10.1016/j.fochms.2021.100067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/29/2021] [Accepted: 12/18/2021] [Indexed: 11/12/2022]
Abstract
Integrated valorization of grape stalks generated lignin, fermentable sugars and nanocellulose. For the first time, xylose was recover from grape stalk. First cellulose nanocrystals recovered from grape stalk. First proof of concept of use of a generated stream from an integrated valorization process. Grape stalks fermentable sugars are consumed to produce bioethanol. Biorefinery is a sustainable way for the processing of grape stalk.
White and red grape stalks biomass were fractioned to maximize its economic value by the production of fermentable sugars, as other value streams. High yields of extractives and lignin were first obtained, originating a biomass rich in cellulose and hemicellulose, which was subject to acid and enzymatic hydrolysis for production of fermentable sugars. Higher concentrations of sugars were obtained by enzymatic than by dilute acid hydrolysis. These biosugars were used for fermentation processes with Pichia stipitis and Saccharomyces cerevisiae. The presence of higher quantities of xylose favoured P. stipitis to produce higher ethanol yields than S. cerevisiae which is glucose lover. Cellulose nanocrystals were produced from the resulting biomass without monosaccharides. For the first time an integrated valorization of grape stalks followed by an application of one of the valorized streams is presented.
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Affiliation(s)
- Tuğba Atatoprak
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal
| | - Maria Manuela Amorim
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal
| | - Tânia Ribeiro
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal
| | - Manuela Pintado
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal
| | - Ana Raquel Madureira
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal
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Bossaert S, Kocijan T, Winne V, Schlich J, Herrera-Malaver B, Verstrepen KJ, Van Opstaele F, De Rouck G, Crauwels S, Lievens B. Beer ethanol and iso-α-acid level affect microbial community establishment and beer chemistry throughout wood maturation of beer. Int J Food Microbiol 2022; 374:109724. [DOI: 10.1016/j.ijfoodmicro.2022.109724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 04/27/2022] [Accepted: 05/15/2022] [Indexed: 10/18/2022]
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Stovicek V, Dato L, Almqvist H, Schöpping M, Chekina K, Pedersen LE, Koza A, Figueira D, Tjosås F, Ferreira BS, Forster J, Lidén G, Borodina I. Rational and evolutionary engineering of Saccharomyces cerevisiae for production of dicarboxylic acids from lignocellulosic biomass and exploring genetic mechanisms of the yeast tolerance to the biomass hydrolysate. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:22. [PMID: 35219341 PMCID: PMC8882276 DOI: 10.1186/s13068-022-02121-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 02/12/2022] [Indexed: 12/13/2022]
Abstract
BACKGROUND Lignosulfonates are significant wood chemicals with a $700 million market, produced by sulfite pulping of wood. During the pulping process, spent sulfite liquor (SSL) is generated, which in addition to lignosulfonates contains hemicellulose-derived sugars-in case of hardwoods primarily the pentose sugar xylose. The pentoses are currently underutilized. If they could be converted into value-added chemicals, overall economic profitability of the process would increase. SSLs are typically very inhibitory to microorganisms, which presents a challenge for a biotechnological process. The aim of the present work was to develop a robust yeast strain able to convert xylose in SSL to carboxylic acids. RESULTS The industrial strain Ethanol Red of the yeast Saccharomyces cerevisiae was engineered for efficient utilization of xylose in a Eucalyptus globulus lignosulfonate stream at low pH using CRISPR/Cas genome editing and adaptive laboratory evolution. The engineered strain grew in synthetic medium with xylose as sole carbon source with maximum specific growth rate (µmax) of 0.28 1/h. Selected evolved strains utilized all carbon sources in the SSL at pH 3.5 and grew with µmax between 0.05 and 0.1 1/h depending on a nitrogen source supplement. Putative genetic determinants of the increased tolerance to the SSL were revealed by whole genome sequencing of the evolved strains. In particular, four top-candidate genes (SNG1, FIT3, FZF1 and CBP3) were identified along with other gene candidates with predicted important roles, based on the type and distribution of the mutations across different strains and especially the best performing ones. The developed strains were further engineered for production of dicarboxylic acids (succinic and malic acid) via overexpression of the reductive branch of the tricarboxylic acid cycle (TCA). The production strain produced 0.2 mol and 0.12 mol of malic acid and succinic acid, respectively, per mol of xylose present in the SSL. CONCLUSIONS The combined metabolic engineering and adaptive evolution approach provided a robust SSL-tolerant industrial strain that converts fermentable carbon content of the SSL feedstock into malic and succinic acids at low pH.in production yields reaching 0.1 mol and 0.065 mol per mol of total consumed carbon sources.. Moreover, our work suggests potential genetic background of the tolerance to the SSL stream pointing out potential gene targets for improving the tolerance to inhibitory industrial feedstocks.
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Affiliation(s)
- Vratislav Stovicek
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800, Kgs. Lyngby, Denmark
| | - Laura Dato
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800, Kgs. Lyngby, Denmark.,River Stone Biotech ApS, Fruebjergvej 3, 2100, Copenhagen, Denmark
| | - Henrik Almqvist
- Department of Chemical Engineering, Lund University, P.O. Box 124, 221 00, Lund, Sweden
| | - Marie Schöpping
- Department of Chemical Engineering, Lund University, P.O. Box 124, 221 00, Lund, Sweden.,Chr. Hansen A/S, Boge Alle 10-12, 2970, Hørsholm, Denmark.,Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Ksenia Chekina
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800, Kgs. Lyngby, Denmark
| | - Lasse Ebdrup Pedersen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800, Kgs. Lyngby, Denmark
| | - Anna Koza
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800, Kgs. Lyngby, Denmark.,Chr. Hansen A/S, Boge Alle 10-12, 2970, Hørsholm, Denmark
| | - Diogo Figueira
- Biotrend S.A., Biocant Park Núcleo 04, Lote 2, 3060-197, Cantanhede, Portugal
| | - Freddy Tjosås
- Borregaard ApS, Hjalmar Wessels vei 6, 1721, Sarpsborg, Norway
| | | | - Jochen Forster
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800, Kgs. Lyngby, Denmark
| | - Gunnar Lidén
- Department of Chemical Engineering, Lund University, P.O. Box 124, 221 00, Lund, Sweden
| | - Irina Borodina
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kemitorvet, Building 220, 2800, Kgs. Lyngby, Denmark.
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Integral Analysis of Liquid-Hot-Water Pretreatment of Wheat Straw: Evaluation of the Production of Sugars, Degradation Products, and Lignin. SUSTAINABILITY 2021. [DOI: 10.3390/su14010362] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Developing sustainable biorefineries is an urgent matter to support the transition to a sustainable society. Lignocellulosic biomass (LCB) is a crucial renewable feedstock for this purpose, and its complete valorization is essential for the sustainability of biorefineries. However, it is improbable that a single pretreatment will extract both sugars and lignin from LCB. Therefore, a combination of pretreatments must be applied. Liquid-hot-water (LHW) is highlighted as a pretreatment for hemicellulose hydrolysis, conventionally analyzed only in terms of sugars and degradation products. However, lignin is also hydrolyzed in the process. The objective of this work was to evaluate LHW at different conditions for sugars, degradation products, and lignin. We performed LHW at 160, 180, and 200 °C for 30, 60, and 90 min using wheat straw and characterized the extract for sugars, degradation products (furfural, hydroxymethylfurfural, and acetic acid), and lignin. Three conditions allowed reaching similar total sugar concentrations (~12 g/L): 160 °C for 90 min, 180 °C for 30 min, and 180 °C for 60 min. Among these, LHW performed at 160 °C for 90 min allowed the lowest concentration of degradation products (0.2, 0.01, and 1.4 g/L for furfural, hydroxymethylfurfural, and acetic acid, respectively) and lignin hydrolysis (2.2 g/L). These values indicate the potential use of the obtained sugars as a fermentation substrate while leaving the lignin in the solid phase for a following stage focused on its extraction and valorization.
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Brink DP, Borgström C, Persson VC, Ofuji Osiro K, Gorwa-Grauslund MF. D-Xylose Sensing in Saccharomyces cerevisiae: Insights from D-Glucose Signaling and Native D-Xylose Utilizers. Int J Mol Sci 2021; 22:12410. [PMID: 34830296 PMCID: PMC8625115 DOI: 10.3390/ijms222212410] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/11/2021] [Accepted: 11/12/2021] [Indexed: 11/17/2022] Open
Abstract
Extension of the substrate range is among one of the metabolic engineering goals for microorganisms used in biotechnological processes because it enables the use of a wide range of raw materials as substrates. One of the most prominent examples is the engineering of baker's yeast Saccharomyces cerevisiae for the utilization of d-xylose, a five-carbon sugar found in high abundance in lignocellulosic biomass and a key substrate to achieve good process economy in chemical production from renewable and non-edible plant feedstocks. Despite many excellent engineering strategies that have allowed recombinant S. cerevisiae to ferment d-xylose to ethanol at high yields, the consumption rate of d-xylose is still significantly lower than that of its preferred sugar d-glucose. In mixed d-glucose/d-xylose cultivations, d-xylose is only utilized after d-glucose depletion, which leads to prolonged process times and added costs. Due to this limitation, the response on d-xylose in the native sugar signaling pathways has emerged as a promising next-level engineering target. Here we review the current status of the knowledge of the response of S. cerevisiae signaling pathways to d-xylose. To do this, we first summarize the response of the native sensing and signaling pathways in S. cerevisiae to d-glucose (the preferred sugar of the yeast). Using the d-glucose case as a point of reference, we then proceed to discuss the known signaling response to d-xylose in S. cerevisiae and current attempts of improving the response by signaling engineering using native targets and synthetic (non-native) regulatory circuits.
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Affiliation(s)
- Daniel P. Brink
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; (C.B.); (V.C.P.); (K.O.O.)
| | - Celina Borgström
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; (C.B.); (V.C.P.); (K.O.O.)
- BioZone Centre for Applied Bioscience and Bioengineering, Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College St., Toronto, ON M5S 3E5, Canada
| | - Viktor C. Persson
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; (C.B.); (V.C.P.); (K.O.O.)
| | - Karen Ofuji Osiro
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; (C.B.); (V.C.P.); (K.O.O.)
- Genetics and Biotechnology Laboratory, Embrapa Agroenergy, Brasília 70770-901, DF, Brazil
| | - Marie F. Gorwa-Grauslund
- Applied Microbiology, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden; (C.B.); (V.C.P.); (K.O.O.)
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Rönnander J, Wright SAI. Growth of wood-inhabiting yeasts of the Faroe Islands in the presence of spent sulphite liquor. Antonie Van Leeuwenhoek 2021; 114:649-666. [PMID: 33851316 PMCID: PMC8137469 DOI: 10.1007/s10482-021-01543-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 02/13/2021] [Indexed: 11/12/2022]
Abstract
In the microbial community of decaying wood, yeasts are important for the recycling of nutrients. Nevertheless, information on their biodiversity in this niche in the Northern hemisphere is limited. Wood-colonising yeasts encounter identical and similar growth-inhibitory compounds as those in spent sulphite liquor (SSL), an energy-rich, acid hydrolysate and waste product from the paper industry, which may render them well-suited for cultivation in SSL. In the present study, yeasts were isolated from decaying wood on the Faroe Islands and identified based on sequence homology of the ITS and D1/D2 regions. Among the yeasts isolated, Candida argentea, Cystofilobasidium infirmominiatum, Naganishia albidosimilis, Naganishia onofrii, Holtermanniella takashimae and Goffeauzyma gastrica were new to decaying wood in cold and temperate climates. C. argentea and Rhodotorula are rarely-isolated species, with no previous documentation from cold and maritime climates. The isolates were further tested for growth in a medium with increasing concentrations of softwood SSL. Most grew in the presence of 10% SSL. Isolates of Debaryomyces sp., C. argentea and Rhodotorula sp. were the most tolerant. Representatives of Debaryomyces and Rhodotorula have previously been found in decaying wood. In contrast, the least tolerant isolates belonged to species that are rarely reported from decaying wood. The relative importance of individual inhibitors to yeast growth is discussed. To our knowledge, none of the present yeast species have previously been cultivated in SSL medium. Decaying wood can be a useful future source of yeasts for valorisation of various hydrolysates to industrial chemicals and biofuels.
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Affiliation(s)
- Jonas Rönnander
- Faculty of Engineering and Sustainable Development, University of Gävle, 80176, Gävle, Sweden
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Maitra S, Singh V. Balancing sugar recovery and inhibitor generation during energycane processing: Coupling cryogenic grinding with hydrothermal pretreatment at low temperatures. BIORESOURCE TECHNOLOGY 2021; 321:124424. [PMID: 33298346 DOI: 10.1016/j.biortech.2020.124424] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 11/12/2020] [Accepted: 11/13/2020] [Indexed: 05/10/2023]
Abstract
Pretreatment of lignocellulosic biomass at high temperatures or with oxidizing chemicals generate various inhibitors that restrict the efficient bioconversion of sugars in subsequent steps. The present study systematically investigates individual and combinatorial effects of pretreatment parameters on the generation of inhibitors. A plot between pretreatment temperature and inhibitor revealed optimum pretreatment temperature for energycane bagasse i.e., 170 °C beyond which total inhibitor production increased exponentially. No inhibitor production was observed on mechanical processing i.e., disk milling/cryogenic grinding of biomass. Evaluation of response surface regression exhibited that biomass solids loading has a significant effect on inhibitor generation at higher temperatures. The concentrations of certain inhibitors such as acetic acid, furfurals, and HMF increased more than 3-folds on doubling the solids loading. Furthermore, a novel low-severity approach of low-temperature hydrothermal pretreatment coupled with cryogenic grinding for lignocellulosic biomasses has been introduced which improved sugar yields while maintaining a low inhibitor concentration.
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Affiliation(s)
- Shraddha Maitra
- Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Vijay Singh
- Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
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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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11
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Huang C, Zheng Y, Lin W, Shi Y, Huang G, Yong Q. Removal of fermentation inhibitors from pre-hydrolysis liquor using polystyrene divinylbenzene resin. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:188. [PMID: 33292538 PMCID: PMC7664058 DOI: 10.1186/s13068-020-01828-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/05/2020] [Indexed: 05/10/2023]
Abstract
BACKGROUND The presence of soluble lignin, furfural and hydroxymethylfurfural (HMF) in industrial pre-hydrolysis liquor (PHL) from the pulping process can inhibit its bioconversion into bioethanol and other biochemicals. Although various technologies have been developed to remove these inhibitors, certain amounts of sugars are also inevitably removed during the treatment process. Hence, polystyrene divinylbenzene (PS-DVB) resin was used as an adsorptive material to simultaneously remove fermentation inhibitors while retaining sugars with high yields to improve the fermentability of PHL after acid hydrolysis by enriching its xylose concentration. The fermentability of acid-hydrolyzed PHL (A-PHL) was evaluated by the bioconversion into ethanol and xylosic acid (XA) after treatment with PS-DVB resin. RESULTS The results showed that the highest xylose concentration (101.1 g/L) in PHL could be obtained by acid hydrolysis at 100 °C for 80 min with 4% acid, while the concentration of fermentation inhibitors (furfural, HMF and lignin) in PHL could also be significantly improved during the acid-hydrolysis process. After treatment with PS-DVB resin, not only were 97% of lignin, 92% of furfural, and 97% of HMF removed from A-PHL, but also 96% of xylose was retained for subsequent fermentation. With resin treatment, the fermentability of A-PHL could be improved by 162-282% for ethanol production from A-PHL containing 30-50 g/L xylose and by 18-828% for XA production from A-PHL containing 90-150 g/L xylose. CONCLUSIONS These results confirmed that PS-DVB resin can remove inhibitors from PHL before producing value-added products by bioconversion. In addition, this work will ideally provide a concept for producing value-added chemicals from pre-hydrolysis liquor, which is regarded as the waste stream in the pulping process.
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Affiliation(s)
- Caoxing Huang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Yayue Zheng
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Wenqian Lin
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Yuxuan Shi
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Guohong Huang
- Department of Material and Structural Engineering, Nanjing Hydraulic Research Institute, Nanjing, 210037, China
| | - Qiang Yong
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China.
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12
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Bu CY, Yan YX, Zou LH, Zheng ZJ, Ouyang J. One-pot biosynthesis of furfuryl alcohol and lactic acid via a glucose coupled biphasic system using single Bacillus coagulans NL01. BIORESOURCE TECHNOLOGY 2020; 313:123705. [PMID: 32593878 DOI: 10.1016/j.biortech.2020.123705] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 06/14/2020] [Accepted: 06/15/2020] [Indexed: 05/12/2023]
Abstract
Furfuryl alcohol is an important reduction product from biomass derived furfural. This study developed one-pot biosynthesis of furfuryl alcohol and lactic acid by a glucose coupled biphasic system using single Bacillus coagulans NL01. Water/dioctyl phthalate is chosen as biphasic system to alleviate the toxicity of furfural and furfuryl alcohol. Under the optimal conditions, the high-concentration conversion (208 mM) of furfural was successfully converted in 6 h reaction with 98% furfural conversion and 88% furfuryl alcohol selectivity. Notably, glucose as co-substrate could be effectively converted to lactic acid in this biphasic system. About 264 mM furfuryl alcohol and 64.2 g/L lactic acid were simultaneously produced from 310 mM furfural and 71.3 g/L glucose within 8.5 h by a fed-batch strategy. The developed approach can not only increase the produced furfuryl alcohol concentration but also reduce the cost of overall approach by lactic acid co-production, indicating its potential for industrial applications.
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Affiliation(s)
- Chong-Yang Bu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, People's Republic of China; College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Yu-Xiu Yan
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China; College of Forestry, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Li-Hua Zou
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, People's Republic of China; College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Zhao-Juan Zheng
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, People's Republic of China; College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China
| | - Jia Ouyang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, People's Republic of China; College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, People's Republic of China.
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13
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Brenelli LB, Figueiredo FL, Damasio A, Franco TT, Rabelo SC. An integrated approach to obtain xylo-oligosaccharides from sugarcane straw: From lab to pilot scale. BIORESOURCE TECHNOLOGY 2020; 313:123637. [PMID: 32535521 DOI: 10.1016/j.biortech.2020.123637] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/02/2020] [Accepted: 06/03/2020] [Indexed: 05/13/2023]
Abstract
Sugarcane straw (SS) is a widely available agricultural processing feedstock with the potential to produce 2nd generation bioethanol and bioproducts, in addition to the more conventional use for heat and/or electrical power generation. In this study, we investigated the operational parameters to maximize the production of xylo-oligosaccharides (XOS) using mild deacetylation, followed by hydrothermal pretreatment. From the laboratory to the pilot-scale, the optimized two-stage pretreatment promoted 81.5% and 70.5% hemicellulose solubilization and led to XOS yields up to 9.8% and 9.1% (w/w of initial straw), respectively. Moreover, different fungal xylanases were also tested to hydrolyze XOS into xylobiose (X2) and xylotriose (X3). GH10 from Aspergillus nidulans performed better than GH11 xylanases and the ratio of the desired products (X2 + X3) increased to 72% due to minimal monomeric sugar formation. Furthermore, a cellulose-rich fraction was obtained, which can be used in other high value-added applications, such as for the production of cello-oligomers.
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Affiliation(s)
- Lívia B Brenelli
- Brazilian Biorenewables National Laboratory (LNBR), Brazilian Center for Research in Energy and Materials (CNPEM), Giuseppe Máximo Scolfaro, 10.000, Campinas, São Paulo, Brazil; Interdisciplinary Center of Energy Planning, University of Campinas, Cora Coralina, 330, Campinas, São Paulo, Brazil
| | - Fernanda L Figueiredo
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - André Damasio
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Telma T Franco
- Interdisciplinary Center of Energy Planning, University of Campinas, Cora Coralina, 330, Campinas, São Paulo, Brazil
| | - Sarita C Rabelo
- Department of Bioprocess and Biotechnology, College of Agricultural Sciences, São Paulo State University (UNESP), Avenida Universitária, 3780 Altos do Paraíso, São Paulo, Brazil.
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14
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El Yamani M, Sakar EH, Boussakouran A, Ghabbour N, Rharrabti Y. Physicochemical and microbiological characterization of olive mill wastewater (OMW) from different regions of northern Morocco. ENVIRONMENTAL TECHNOLOGY 2020; 41:3081-3093. [PMID: 30896341 DOI: 10.1080/09593330.2019.1597926] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Accepted: 03/14/2019] [Indexed: 06/09/2023]
Abstract
This work examined the influence of crop season, extraction system and production site on the composition of fresh olive mill wastewater collected from northern Morocco. ANOVA analysis showed that most of the traits were largely affected by the extraction system (≥60% of total variance). Comparison among extraction systems showed significant differences for all traits, except for chlorides. Three phase centrifugation system (C3) displayed the highest value of total phenols, while all the remaining traits were higher in two phase centrifugation system (C2). Concerning crop seasons, we noticed a general decrease in values of total solids, chemical oxygen demand, chlorides, C/N ratio and total aerobic mesophilic flora, from 2014 to 2016 season; in contrast, an increase in suspended solids, total kjeldahl nitrogen and proteins was detected. OMW with highest total phenols content and then more acidic were collected during 2015 season. Between production sites, Bni Frassen produced OMW with the highest values for salt and total phenols, but the lowest ones were obtained for microbiological traits. OMW from Taza were rich in total kjeldahl nitrogen and proteins. An increase in organic load indicators was observed in Bouchfaa. Principal component analysis (PCA) explained about 82% of total variability: 58%, 16% and 8% for principal component 1 (PC1), PC2 and PC3, respectively. Extraction system fitted the variability of PC1. PC2 was mainly explained by production sites, while PC3 separated crop seasons. Correlation studies showed significant relationships especially among the traits expressing organic load, while microbiological counts were largely associated to total phenols and pH.
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Affiliation(s)
- Mohamed El Yamani
- Laboratory of Natural Resources and Environment, Polydisciplinary Faculty of Taza, Sidi Mohamed Ben Abdellah University, Taza, Morocco
| | - El Hassan Sakar
- Laboratory of Natural Resources and Environment, Polydisciplinary Faculty of Taza, Sidi Mohamed Ben Abdellah University, Taza, Morocco
| | - Abdelali Boussakouran
- Laboratory of Natural Resources and Environment, Polydisciplinary Faculty of Taza, Sidi Mohamed Ben Abdellah University, Taza, Morocco
| | - Nabil Ghabbour
- Laboratory of Biochemistry and Biotechnology, Faculty of Science, Mohammed First University, Oujda, Morocco
| | - Yahia Rharrabti
- Laboratory of Natural Resources and Environment, Polydisciplinary Faculty of Taza, Sidi Mohamed Ben Abdellah University, Taza, Morocco
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15
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Antonopoulou G. Designing Efficient Processes for Sustainable Bioethanol and Bio-Hydrogen Production from Grass Lawn Waste. Molecules 2020; 25:molecules25122889. [PMID: 32586042 PMCID: PMC7355486 DOI: 10.3390/molecules25122889] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 06/20/2020] [Accepted: 06/21/2020] [Indexed: 12/04/2022] Open
Abstract
The effect of thermal, acid and alkali pretreatment methods on biological hydrogen (BHP) and bioethanol production (BP) from grass lawn (GL) waste was investigated, under different process schemes. BHP from the whole pretreatment slurry of GL was performed through mixed microbial cultures in simultaneous saccharification and fermentation (SSF) mode, while BP was carried out through the C5yeast Pichia stipitis, in SSF mode. From these experiments, the best pretreatment conditions were determined and the efficiencies for each process were assessed and compared, when using either the whole pretreatment slurry or the separated fractions (solid and liquid), the separate hydrolysis and fermentation (SHF) or SSF mode, and especially for BP, the use of other yeasts such as Pachysolen tannophilus or Saccharomyces cerevisiae. The experimental results showed that pretreatment with 10 gH2SO4/100 g total solids (TS) was the optimum for both BHP and BP. Separation of solid and liquid pretreated fractions led to the highest BHP (270.1 mL H2/g TS, corresponding to 3.4 MJ/kg TS) and also BP (108.8 mg ethanol/g TS, corresponding to 2.9 MJ/kg TS) yields. The latter was achieved by using P. stipitis for the fermentation of the hydrolysate and S. serevisiae for the solid fraction fermentation, at SSF.
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Affiliation(s)
- Georgia Antonopoulou
- Institute of Chemical Engineering Sciences, Stadiou, Platani, 26504 Patras, Greece
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16
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Youssef ASA, Hemdan MM, Azab ME, Emara SA, Elsayed GA, Kamel RM. Syringaldehyde as a scaffold for the synthesis of some biologically potent heterocycles. J Heterocycl Chem 2020. [DOI: 10.1002/jhet.3850] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ahmed S. A. Youssef
- Chemistry Department, Faculty of ScienceAin Shams University Abbasia Cairo Egypt
| | - Magdy M. Hemdan
- Chemistry Department, Faculty of ScienceAin Shams University Abbasia Cairo Egypt
| | - Mohammad E. Azab
- Chemistry Department, Faculty of ScienceAin Shams University Abbasia Cairo Egypt
| | - Samir A. Emara
- Chemistry Department, Faculty of ScienceAin Shams University Abbasia Cairo Egypt
| | - Galal A. Elsayed
- Chemistry Department, Faculty of ScienceAin Shams University Abbasia Cairo Egypt
| | - Rabaa M. Kamel
- Chemistry Department, Faculty of ScienceAin Shams University Abbasia Cairo Egypt
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17
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Ligninolytic Enzymes Mediated Ligninolysis: An Untapped Biocatalytic Potential to Deconstruct Lignocellulosic Molecules in a Sustainable Manner. Catal Letters 2020. [DOI: 10.1007/s10562-019-03096-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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18
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Characterization of the Furfural and 5-Hydroxymethylfurfural (HMF) Metabolic Pathway in the Novel Isolate Pseudomonas putida ALS1267. Appl Biochem Biotechnol 2019; 190:918-930. [PMID: 31605303 DOI: 10.1007/s12010-019-03130-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 08/25/2019] [Indexed: 10/25/2022]
Abstract
The genes involved in the aerobic bacterial metabolism of furfural and 5-hydroxymethylfurfural (HMF) have been characterized in two species, Pseudomonas putida Fu1 and Cupriavidus basilensis HMF14. A third furan-metabolizing strain, Pseudomonas putida ALS1267, was recently identified that grows robustly on both furfural and HMF as sole carbon sources, with a growth rate of 0.250 h-1 on furfural and 0.311 h-1 on HMF, and we have characterized the genes involved in furfural and HMF metabolism in this bacterium. Unlike C. basilensis HMF14, which contains separate furfural and HMF operons, P. putida ALS1267 contains one contiguous 18.1-kb operon, which harbors all of the furfural- and HMF-metabolizing genes except for one, the hmfH gene that encodes HMF/furfural oxidoreductase and has both HMF acid oxidase and furfural/HMF dehydrogenase activity. The 18.1-kb operon was cloned into P. putida KT2440, which cannot metabolize furans, enabling growth on furfural as the sole carbon source with a growth rate of 0.340 h-1. The clone did not allow P. putida KT2440 to metabolize HMF, most likely due to the lack of the hmfH gene. No hmfH homolog was identified in P. putida ALS1267, suggesting that another gene in the ALS1267 genome provides this function.
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19
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Ben Atitallah I, Antonopoulou G, Ntaikou I, Alexandropoulou M, Nasri M, Mechichi T, Lyberatos G. On the evaluation of different saccharification schemes for enhanced bioethanol production from potato peels waste via a newly isolated yeast strain of Wickerhamomyces anomalus. BIORESOURCE TECHNOLOGY 2019; 289:121614. [PMID: 31203181 DOI: 10.1016/j.biortech.2019.121614] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 06/03/2019] [Accepted: 06/06/2019] [Indexed: 06/09/2023]
Abstract
The present study focuses on the exploration of the potential use of potato peels waste (PPW) as feedstock for bioethanol production, using a newly isolated yeast strain, Wickerhamomyces anomalus, via different saccharification and fermentation schemes. The saccharification of PPW was performed via thermal and chemical (acid, alkali) pretreatment, as well as via enzymatic hydrolysis through the use of commercial enzymes (cellulase and amylase) or enzymes produced at lab scale (alpha-amylase from Bacillus sp. Gb67), either separately or in mixtures. The results indicated that the enzymatic treatment by commercial enzymes led to a higher saccharification efficiency (72.38%) and ethanol yield (0.49 g/gconsumed sugars) corresponding to 96% of the maximum theoretical. In addition, acid pretreatment was found to be beneficial for the process, leading also to high hydrolysis and ethanol yields, indicating that PPW is a very promising feedstock for bio-ethanol production by W. anomalus under different process schemes.
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Affiliation(s)
- Imen Ben Atitallah
- Laboratory of Enzyme Engineering and Microbiology, National School of Engineers of Sfax, University of Sfax, BP 1173, 3038 Sfax, Tunisia; Laboratory of Biochemistry and Enzymatic Engineering of Lipases, National School of Engineers of Sfax, University of Sfax, 3038 Sfax, Tunisia
| | - Georgia Antonopoulou
- Institute of Chemical Engineering Sciences, Stadiou, Platani, Patras GR 26504, Greece.
| | - Ioanna Ntaikou
- Institute of Chemical Engineering Sciences, Stadiou, Platani, Patras GR 26504, Greece
| | - Maria Alexandropoulou
- Institute of Chemical Engineering Sciences, Stadiou, Platani, Patras GR 26504, Greece
| | - Moncef Nasri
- Laboratory of Enzyme Engineering and Microbiology, National School of Engineers of Sfax, University of Sfax, BP 1173, 3038 Sfax, Tunisia
| | - Tahar Mechichi
- Laboratory of Biochemistry and Enzymatic Engineering of Lipases, National School of Engineers of Sfax, University of Sfax, 3038 Sfax, Tunisia
| | - Gerasimos Lyberatos
- Institute of Chemical Engineering Sciences, Stadiou, Platani, Patras GR 26504, Greece; School of Chemical Engineering, National Technical University of Athens, GR 15780 Athens, Greece
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20
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Dessie W, Xin F, Zhang W, Zhou J, Wu H, Ma J, Jiang M. Inhibitory effects of lignocellulose pretreatment degradation products (hydroxymethylfurfural and furfural) on succinic acid producing Actinobacillus succinogenes. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.107263] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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21
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Todhanakasem T, Salangsing OL, Koomphongse P, Kaewket S, Kanokratana P, Champreda V. Zymomonas mobilis Biofilm Reactor for Ethanol Production Using Rice Straw Hydrolysate Under Continuous and Repeated Batch Processes. Front Microbiol 2019; 10:1777. [PMID: 31440218 PMCID: PMC6693309 DOI: 10.3389/fmicb.2019.01777] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/18/2019] [Indexed: 11/13/2022] Open
Abstract
Plastic composited corn silk was developed as a biotic/abiotic carrier for Zymomonas mobilis biofilm formation for the purpose of ethanol production. Furthermore, we explored the use of rice straw hydrolysate as substrate in both multistage continuous culture and repeated batch processes and compared the ethanol production efficiency by two strains of Z. mobilis. Biofilm formed by bacterial strains Z. mobilis ZM4 and TISTR551 were detected, and its proficiencies were compared under various conditions by scanning electron microscopy (SEM) and crystal violet assays. The greatest biofilm formed by both strains was found on day five after the inoculation. Z. mobilis strain ZM4 grown in repeated batch biofilm reactors produced higher yields of ethanol than TISTR551 grown under the same conditions, while TISTR551 produced higher yields of ethanol in the multistage continuous process. The yields were highly maintained, with no significant differences (p < 0.05) among the three consecutive repeated batches. These experiments highlight exciting uses for agricultural byproducts in the production of ethanol using Z. mobilis biofilm reactors.
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Affiliation(s)
- Tatsaporn Todhanakasem
- Department of Agro-Industry, Faculty of Biotechnology, Assumption University, Bangkok, Thailand
| | - O-Lan Salangsing
- Department of Agro-Industry, Faculty of Biotechnology, Assumption University, Bangkok, Thailand
| | - Piyawit Koomphongse
- National Metal and Materials Technology Center (MTEC), Klong Luang, Thailand
| | - Sanya Kaewket
- National Metal and Materials Technology Center (MTEC), Klong Luang, Thailand
| | - Pattanop Kanokratana
- National Center for Genetic Engineering and Biotechnology (BIOTEC), Klong Luang, Thailand
| | - Verawat Champreda
- National Center for Genetic Engineering and Biotechnology (BIOTEC), Klong Luang, Thailand
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22
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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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23
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Sunwoo I, Kwon JE, Nguyen TH, Jeong GT, Kim SK. Ethanol production from water hyacinth (Eichhornia crassipes) hydrolysate by hyper-thermal acid hydrolysis, enzymatic saccharification and yeasts adapted to high concentration of xylose. Bioprocess Biosyst Eng 2019; 42:1367-1374. [DOI: 10.1007/s00449-019-02136-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Accepted: 04/24/2019] [Indexed: 11/24/2022]
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24
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Oktaviani M, Hermiati E, Thontowi A, Laksana RPB, Kholida LN, Andriani A, Yopi, Mangunwardoyo W. Production of xylose, glucose, and other products from tropical lignocellulose biomass by using maleic acid pretreatment. ACTA ACUST UNITED AC 2019. [DOI: 10.1088/1755-1315/251/1/012013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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25
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Zhou P, Khushk I, Gao Q, Bao J. Tolerance and transcriptional analysis of Corynebacterium glutamicum on biotransformation of toxic furaldehyde and benzaldehyde inhibitory compounds. J Ind Microbiol Biotechnol 2019; 46:951-963. [PMID: 30972584 DOI: 10.1007/s10295-019-02171-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Accepted: 04/01/2019] [Indexed: 11/26/2022]
Abstract
Furaldehydes and benzaldehydes are among the most toxic inhibitors from lignocellulose pretreatment on microbial growth and metabolism. The bioconversion of aldehyde inhibitors into less toxic alcohols or acids (biotransformation) is the prerequisite condition for efficient biorefinery fermentations. This study found that Corynebacterium glutamicum S9114 demonstrated excellent tolerance and biotransformation capacity to five typical aldehyde inhibitors including two furaldehydes: 2-furaldehyde (furfural), 5-(hydroxymethyl)-2-furaldehyde, and three benzaldehydes: 4-hydroxybenzaldehyde, 4-hydroxy-3-methoxybenzaldehyde (vanillin), and 4-hydroxy-3,5-dimethoxybenzaldehyde (syringaldehyde). Transcription levels of 93 genes hypothesized to be responsible for five aldehydes biotransformation were examined by qRT-PCR. Multiple genes showed significantly up-regulated expression against furaldehydes or benzaldehydes. Overexpression of CGS9114_RS01115 in C. glutamicum resulted in the increased conversion of all five aldehyde inhibitors. The significant oxidoreductase genes responsible for each or multiple inhibitors biotransformation identified in this study will serve as a component of key gene device library for robust biorefinery fermentation strains development in the future biorefinery applications.
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Affiliation(s)
- Pingping Zhou
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Imrana Khushk
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Qiuqiang Gao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Jie Bao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China.
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26
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Prasad S, Malav MK, Kumar S, Singh A, Pant D, Radhakrishnan S. Enhancement of bio-ethanol production potential of wheat straw by reducing furfural and 5-hydroxymethylfurfural (HMF). ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.biteb.2018.09.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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27
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Parra-Ramírez D, Martinez A, Cardona CA. Technical and economic potential evaluation of the strain Escherichia coli MS04 in the ethanol production from glucose and xylose. Biochem Eng J 2018. [DOI: 10.1016/j.bej.2018.09.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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28
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Papadaki A, Papapostolou H, Alexandri M, Kopsahelis N, Papanikolaou S, de Castro AM, Freire DMG, Koutinas AA. Fumaric acid production using renewable resources from biodiesel and cane sugar production processes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:35960-35970. [PMID: 29654455 DOI: 10.1007/s11356-018-1791-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 03/19/2018] [Indexed: 06/08/2023]
Abstract
The microbial production of fumaric acid by Rhizopus arrhizus NRRL 2582 has been evaluated using soybean cake from biodiesel production processes and very high polarity (VHP) sugar from sugarcane mills. Soybean cake was converted into a nutrient-rich hydrolysate via a two-stage bioprocess involving crude enzyme production via solid state fermentations (SSF) of either Aspergillus oryzae or R. arrhizus cultivated on soybean cake followed by enzymatic hydrolysis of soybean cake. The soybean cake hydrolysate produced using crude enzymes derived via SSF of R. arrhizus was supplemented with VHP sugar and evaluated using different initial free amino nitrogen (FAN) concentrations (100, 200, and 400 mg/L) in fed-batch cultures for fumaric acid production. The highest fumaric acid concentration (27.3 g/L) and yield (0.7 g/g of total consumed sugars) were achieved when the initial FAN concentration was 200 mg/L. The combination of VHP sugar with soybean cake hydrolysate derived from crude enzymes produced by SSF of A. oryzae at 200 mg/L initial FAN concentration led to the production of 40 g/L fumaric acid with a yield of 0.86 g/g of total consumed sugars. The utilization of sugarcane molasses led to low fumaric acid production by R. arrhizus, probably due to the presence of various minerals and phenolic compounds. The promising results achieved through the valorization of VHP sugar and soybean cake suggest that a focused study on molasses pretreatment could lead to enhanced fumaric acid production.
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Affiliation(s)
- Aikaterini Papadaki
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece
| | - Harris Papapostolou
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece
| | - Maria Alexandri
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece
- Department of Bioengineering, Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB), Max-Eyth-Allee 100, 14469, Potsdam, Germany
| | - Nikolaos Kopsahelis
- Department of Food Technology, Technological Educational Institute (TEI) of Ionian Islands, Argostoli, 28100, Kefalonia, Greece
| | - Seraphim Papanikolaou
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece
| | | | - Denise M G Freire
- Biochemistry Department, Chemistry Institute, Federal University of Rio de Janeiro, Cidade Universitária, Centro de Tecnologia, Bloco A, Lab, Rio de Janeiro, RJ, 549, Brazil
| | - Apostolis A Koutinas
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 11855, Athens, Greece.
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29
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Yabushita M, Grosso-Giordano NA, Fukuoka A, Katz A. Selective Sequestration of Aromatics from Aqueous Mixtures with Sugars by Hydrophobic Molecular Calixarene Cavities Grafted on Silica. ACS APPLIED MATERIALS & INTERFACES 2018; 10:39670-39678. [PMID: 30398841 DOI: 10.1021/acsami.8b13273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The separation of aromatic contaminants from sugar-aromatic aqueous mixtures is required in second-generation biorefineries because aromatic compounds deactivate (bio)catalysts typically involved in upgrading lignocellulosic biomass to fuels and chemicals. This separation remains challenging, however, because of the degree of molecular recognition needed to sequester dilute aromatic impurities from concentrated sugar streams. Herein, we demonstrate that hydrophobic cavities of p- tert-butylcalix[4]arene macrocycles grafted on amorphous silica (calix/SiO2) perform this separation selectively and efficiently by acting as selective molecular hosts that adsorb aromatic compounds (5-hydroxymethylfurfural, vanillin, and vanillic acid) while excluding monomeric sugar (glucose chosen as a prototypical model) in aqueous mixtures. By comparing calix/SiO2 to a range of organically modified SiO2 surfaces and other porous adsorbents, we demonstrate that the organization of hydrophobic functional groups within discrete nests consisting of calixarene cavities is crucial for facilitating the adsorption of aromatics. Density functional theory calculations of the host-guest complex indicate that adsorption is brought about by weak dispersive (van der Waals) interactions between tert-butyl upper-rim substituents in calixarene hosts and aromatic guests. Calix/SiO2 can be repeatedly reused, demonstrating its viability as an adsorbent within a continuous biorefining process. These calix/SiO2 adsorbents expand the palette of materials available for selective sugar-aromatic separations, which until now have been limited to pyrene-based sites of metal-organic framework NU-1000, and demonstrate that sites consisting of relatively simple hydrophobic tert-butyl substituents organized around a hemispherical molecular cavity provide a sufficient degree of molecular recognition for performing this separation selectively.
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Affiliation(s)
- Mizuho Yabushita
- Department of Chemical and Biomolecular Engineering , University of California, Berkeley , Berkeley , California 94720 , United States
- Institute for Catalysis , Hokkaido University , Sapporo , Hokkaido 001-0021 , Japan
| | - Nicolás A Grosso-Giordano
- Department of Chemical and Biomolecular Engineering , University of California, Berkeley , Berkeley , California 94720 , United States
| | - Atsushi Fukuoka
- Institute for Catalysis , Hokkaido University , Sapporo , Hokkaido 001-0021 , Japan
| | - Alexander Katz
- Department of Chemical and Biomolecular Engineering , University of California, Berkeley , Berkeley , California 94720 , United States
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Chang D, Yu Z, Ul Islam Z, French WT, Zhang Y, Zhang H. Proteomic and metabolomic analysis of the cellular biomarkers related to inhibitors tolerance in Zymomonas mobilis ZM4. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:283. [PMID: 30356850 PMCID: PMC6190654 DOI: 10.1186/s13068-018-1287-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 10/09/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Toxic compounds present in both the hydrolysate and pyrolysate of lignocellulosic biomass severely hinder the further conversion of lignocellulose-derived fermentable sugars into useful chemicals by common biocatalysts like Zymomonas mobilis, which has remarkable advantages over yeast. Although the extra detoxification treatment prior to fermentation process can help biocatalysts to eliminate the inhibitory environment, it is not environment friendly and cost effective for industrial application. As also reported by previous studies, an ideal and holistic approach to solve this issue is to develop microbial strains with inhibitor tolerance. However, previously engineered strains had the limitation that they could not cope well with the synergistic effect of multiple inhibitors as they are resistant only to a single inhibitor. Hence, understanding the universal cellular responses of Z. mobilis to various inhibitors may guide the designing of rational strategies to obtain more robust engineered strains for biofuel production from lignocellulosic biomass. RESULTS Quantitative proteomics and metabolomics approaches were used to determine the cellular responses of Z. mobilis ZM4 to representative biomass-derived inhibitors like formic acid, acetic acid, furfural, 5-hydroxymethylfurfural, and phenol. The differentially expressed proteins identified under the challenge of single and combined inhibitors were involved in cell wall/membrane biogenesis, energy production, DNA replication, DNA recombination, DNA repair, DNA transcription, RNA translation, posttranslational modification, biosynthesis of amino acids, central carbon metabolism, etc. Metabolomics analysis showed that the up- or down-regulation pattern of metabolites was changed consistently with that of relevant proteins. CONCLUSION Fifteen up-regulated proteins (e.g., Isopropylmalate isomerase LeuC, transcription-repair-coupling factor Mfd, and phosphoglucose isomerase PGI) and thirteen down-regulated proteins (e.g., TonB-dependent transporter ZMO1522, transcription termination factor Rho, and S1/P1 nuclease ZMO0127) were identified as candidate proteins related to all the stress conditions, implying that these proteins are potential biomarkers for the improvement of Z. mobilis ZM4 to resist complex biomass-derived inhibitors. These data can be used to generate a database of inhibitor-tolerance biomarkers, which could provide a basis for engineering Z. mobilis that would be able to grow in the presence of multiple inhibitors and directly ferment the biomass-derived sugars into biofuels.
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Affiliation(s)
- Dongdong Chang
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Shijingshan District, Beijing, 100049 People’s Republic of China
| | - Zhisheng Yu
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Shijingshan District, Beijing, 100049 People’s Republic of China
| | - Zia Ul Islam
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Shijingshan District, Beijing, 100049 People’s Republic of China
- Department of Sustainable Bioproducts, Mississippi State University, Mississippi State, MS 39762 USA
| | - W. Todd French
- Dave C. Swalm School of Chemical Engineering, Mississippi State University, P.O. Box 9595, Mississippi State, MS 39762 USA
| | - Yiming Zhang
- Environmental Protection Bureau, Shunyi District, Beijing, 101300 People’s Republic of China
| | - Hongxun Zhang
- College of Resources and Environment, University of Chinese Academy of Sciences, 19 A Yuquan Road, Shijingshan District, Beijing, 100049 People’s Republic of China
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Vargas R, Vecchietti A. Modeling the Thermochemical Pretreatment of Eucalyptus globulus for Bioethanol Production. Ind Eng Chem Res 2018. [DOI: 10.1021/acs.iecr.8b02706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Rafael Vargas
- INGAR - CONICET - UTN Avellaneda 3657, Santa Fe 3000, Argentina
| | - Aldo Vecchietti
- INGAR - CONICET - UTN Avellaneda 3657, Santa Fe 3000, Argentina
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Application of the Severity Factor and HMF Removal of Red Macroalgae Gracilaria verrucosa to Production of Bioethanol by Pichia stipitis and Kluyveromyces marxianus with Adaptive Evolution. Appl Biochem Biotechnol 2018; 187:1312-1327. [DOI: 10.1007/s12010-018-2888-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 09/10/2018] [Indexed: 12/19/2022]
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Jayakody LN, Turner TL, Yun EJ, Kong II, Liu JJ, Jin YS. Expression of Gre2p improves tolerance of engineered xylose-fermenting Saccharomyces cerevisiae to glycolaldehyde under xylose metabolism. Appl Microbiol Biotechnol 2018; 102:8121-8133. [DOI: 10.1007/s00253-018-9216-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 06/28/2018] [Accepted: 07/02/2018] [Indexed: 12/17/2022]
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Zhang Y, Xia C, Lu M, Tu M. Effect of overliming and activated carbon detoxification on inhibitors removal and butanol fermentation of poplar prehydrolysates. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:178. [PMID: 29983741 PMCID: PMC6020205 DOI: 10.1186/s13068-018-1182-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 06/20/2018] [Indexed: 05/26/2023]
Abstract
BACKGROUND Biomass prehydrolysates from dilute acid pretreatment contain a considerable amount of fermentable sugars for biofuels production. However, carbonyl degradation compounds present severe toxicity to fermentation microbes. Furans (such as furfural and hydroxymethylfurfural), aliphatic acids (such as acetic acid, formic acid and levulinic acid) and phenolic compounds (such as vanillin and syringaldehyde) have been suggested to be the main inhibitors in biomass prehydrolysates. However, no single compound has been determined as the dominant toxic inhibitor. The effects of various detoxification methods on inhibitors removal have not been fully understood. RESULTS The effects of overliming and activated carbon (AC) detoxification on the removal of inhibitors and butanol fermentation of the poplar prehydrolysates were investigated. Gas chromatography-mass spectrometry (GC/MS) was used to identify and quantify 46 carbonyl compounds as potential inhibitors. It was observed that overliming and AC treatment alone did not make the prehydrolysates fermentable with Clostridium saccharobutylicum. The sequential overliming and AC resulted in a remarkable fermentability and a high butanol yield at 0.22 g g-1 sugar. The inhibitor removal in the prehydrolysates treated by overliming and AC was also examined by GC/MS. Overliming removed 75.6% of furan derivatives and 68.1% of aromatic monomers. In comparison, AC (5.0% w/v) removed 77.9% of furan derivatives and 98.6% of aromatic monomers. In addition, overliming removed much more 2,5-furandicarboxyaldehyde, 5-ethylfuran-2-carbaldehyde and 2,5-hexanedione than AC did. On the contrary, AC could remove considerably more phenolic acids than overliming. In the sequential detoxification, both dialdehydes/diketones and phenolic acids were extensively removed. This could be the main reason why the sequential detoxification enabled a remarkable ABE fermentation for the prehydrolysates. CONCLUSIONS This study indicated that the effect of overliming and AC treatment on inhibitors removal was related to their chemical structures. Overliming removed more dialdehydes and diketones than AC treatment, while AC removed more phenolic acids than overliming. Sequential overliming and AC treatment were required to make the prehydrolysates fermentable with C. saccharobutylicum. The study also suggested different detoxification method was needed for ABE fermentation of the prehydrolysate as compared to ethanol fermentation.
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Affiliation(s)
- Yu Zhang
- Department of Chemical and Environmental Engineering, University of Cincinnati, 2901 Woodside Drive, Cincinnati, OH 45221 USA
| | - Changlei Xia
- Department of Chemical and Environmental Engineering, University of Cincinnati, 2901 Woodside Drive, Cincinnati, OH 45221 USA
| | - Mingming Lu
- Department of Chemical and Environmental Engineering, University of Cincinnati, 2901 Woodside Drive, Cincinnati, OH 45221 USA
| | - Maobing Tu
- Department of Chemical and Environmental Engineering, University of Cincinnati, 2901 Woodside Drive, Cincinnati, OH 45221 USA
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Allopurinol supplementation of the growth medium enhances the fermentation of lignocellulosic hydrolysates to ethanol by Saccharomyces cerevisiae. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2018. [DOI: 10.1016/j.bcab.2018.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Yang Y, Hu M, Tang Y, Geng B, Qiu M, He Q, Chen S, Wang X, Yang S. Progress and perspective on lignocellulosic hydrolysate inhibitor tolerance improvement in Zymomonas mobilis. BIORESOUR BIOPROCESS 2018. [DOI: 10.1186/s40643-018-0193-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Pinto ASS, Ribeiro MPA, Farinas CS. Fast spectroscopic monitoring of inhibitors in the 2G ethanol process. BIORESOURCE TECHNOLOGY 2018; 250:148-154. [PMID: 29161574 DOI: 10.1016/j.biortech.2017.11.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/09/2017] [Accepted: 11/10/2017] [Indexed: 05/22/2023]
Abstract
One of the main challenges of second generation (2G) ethanol production is the high quantities of phenolic compounds and furan derivatives generated in the pretreatment of the lignocellulosic biomass, which inhibit the enzymatic hydrolysis and fermentation steps. Fast monitoring of these inhibitory compounds could provide better control of the pretreatment, hydrolysis, and fermentation processes by enabling the implementation of strategic process control actions. We investigated the feasibility of monitoring these inhibitory compounds by ultraviolet-visible (UV-Vis) spectroscopy associated with partial least squares (PLS) regression. Hydroxymethylfurfural, furfural, vanillin, and ferulic and p-coumaric acids generated during different severities of liquid hot water pretreatment of sugarcane bagasse were quantified with highly accuracy. In cross-validation (leave-one-out), the PLS-UV-Vis method presented root mean square error of prediction (RMSECV) of around only 5.0%. The results demonstrated that the monitoring performance achieved with PLS-UV-Vis could support future studies of optimization and control protocols for application in industrial processes.
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Affiliation(s)
- Ariane S S Pinto
- Graduate Program of Chemical Engineering, Federal University of São Carlos, 13565-905, PO Box 676, São Carlos, SP, Brazil; Embrapa Instrumentation, Rua XV de Novembro 1452, 13560-970 São Carlos, SP, Brazil
| | - Marcelo P A Ribeiro
- Graduate Program of Chemical Engineering, Federal University of São Carlos, 13565-905, PO Box 676, São Carlos, SP, Brazil; Chemical Engineering Department, Federal University of São Carlos, 13565-905, PO Box 676, São Carlos, SP, Brazil
| | - Cristiane S Farinas
- Graduate Program of Chemical Engineering, Federal University of São Carlos, 13565-905, PO Box 676, São Carlos, SP, Brazil; Embrapa Instrumentation, Rua XV de Novembro 1452, 13560-970 São Carlos, SP, Brazil.
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Loow YL, Wu TY, Yang GH, Ang LY, New EK, Siow LF, Md Jahim J, Mohammad AW, Teoh WH. Deep eutectic solvent and inorganic salt pretreatment of lignocellulosic biomass for improving xylose recovery. BIORESOURCE TECHNOLOGY 2018; 249:818-825. [PMID: 29136937 DOI: 10.1016/j.biortech.2017.07.165] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 07/26/2017] [Accepted: 07/27/2017] [Indexed: 06/07/2023]
Abstract
Deep eutectic solvents (DESs) have received considerable attention in recent years due to their low cost, low toxicity, and biodegradable properties. In this study, a sequential pretreatment comprising of a DES (choline chloride:urea in a ratio of 1:2) and divalent inorganic salt (CuCl2) was evaluated, with the aim of recovering xylose from oil palm fronds (OPF). At a solid-to-liquid ratio of 1:10 (w/v), DES alone was ineffective in promoting xylose extraction from OPF. However, a combination of DES (120°C, 4h) and 0.4mol/L of CuCl2 (120°C, 30min) resulted in a pretreatment hydrolysate containing 14.76g/L of xylose, remarkably yielding 25% more xylose than the CuCl2-only pretreatment (11.87g/L). Characterization studies such as FE-SEM, BET, XRD, and FTIR confirmed the delignification of OPF when DES was implemented. Thus, the use of this integrated pretreatment system enabled xylose recoveries which were comparable with other traditional pretreatments.
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Affiliation(s)
- Yu-Loong Loow
- Chemical Engineering Discipline, School of Engineering, Monash University, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
| | - Ta Yeong Wu
- Chemical Engineering Discipline, School of Engineering, Monash University, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia.
| | - Ge Hoa Yang
- Chemical Engineering Discipline, School of Engineering, Monash University, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia; Undergraduate Research Opportunities Program (UROP), School of Engineering, Monash University, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
| | - Lin Yang Ang
- Chemical Engineering Discipline, School of Engineering, Monash University, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
| | - Eng Kein New
- Chemical Engineering Discipline, School of Engineering, Monash University, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia; Undergraduate Research Opportunities Program (UROP), School of Engineering, Monash University, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
| | - Lee Fong Siow
- School of Science, Monash University, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
| | - Jamaliah Md Jahim
- Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia
| | - Abdul Wahab Mohammad
- Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia
| | - Wen Hui Teoh
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia
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Lyra Colombi B, Silva Zanoni PR, Benathar Ballod Tavares L. Effect of phenolic compounds on bioconversion of glucose to ethanol by yeast Saccharomyces cerevisiae
PE-2. CAN J CHEM ENG 2018. [DOI: 10.1002/cjce.23114] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Amamou S, Sambusiti C, Monlau F, Dubreucq E, Barakat A. Mechano-Enzymatic Deconstruction with a New Enzymatic Cocktail to Enhance Enzymatic Hydrolysis and Bioethanol Fermentation of Two Macroalgae Species. Molecules 2018; 23:molecules23010174. [PMID: 29342098 PMCID: PMC6017876 DOI: 10.3390/molecules23010174] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 12/19/2017] [Accepted: 01/07/2018] [Indexed: 11/27/2022] Open
Abstract
The aim of this study was to explore the efficiency of a mechano-enzymatic deconstruction of two macroalgae species for sugars and bioethanol production, by using a new enzymatic cocktail (Haliatase) and two types of milling modes (vibro-ball: VBM and centrifugal milling: CM). By increasing the enzymatic concentration from 3.4 to 30 g/L, the total sugars released after 72 h of hydrolysis increased (from 6.7 to 13.1 g/100 g TS and from 7.95 to 10.8 g/100 g TS for the green algae U. lactuca and the red algae G. sesquipedale, respectively). Conversely, total sugars released from G. sesquipedale increased (up to 126% and 129% after VBM and CM, respectively). The best bioethanol yield (6 geth/100 g TS) was reached after 72 h of fermentation of U. lactuca and no increase was obtained after centrifugal milling. The latter led to an enhancement of the ethanol yield of G. sesquipedale (from 2 to 4 g/100 g TS).
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Affiliation(s)
- Sameh Amamou
- UMR, Ingénierie des Agropolymères et des Technologies Emergentes (IATE), CIRAD, Montpellier SupAgro, INRA, Université de Montpellier, 34060 Montpellier, France.
| | - Cecilia Sambusiti
- UMR, Ingénierie des Agropolymères et des Technologies Emergentes (IATE), CIRAD, Montpellier SupAgro, INRA, Université de Montpellier, 34060 Montpellier, France.
| | - Florian Monlau
- UMR, Ingénierie des Agropolymères et des Technologies Emergentes (IATE), CIRAD, Montpellier SupAgro, INRA, Université de Montpellier, 34060 Montpellier, France.
- APESA, Plateau Technique, Cap Ecologia, Avenue Fréderic Joliot Curie, 64230 Lescar, France.
| | - Eric Dubreucq
- UMR, Ingénierie des Agropolymères et des Technologies Emergentes (IATE), CIRAD, Montpellier SupAgro, INRA, Université de Montpellier, 34060 Montpellier, France.
| | - Abdellatif Barakat
- UMR, Ingénierie des Agropolymères et des Technologies Emergentes (IATE), CIRAD, Montpellier SupAgro, INRA, Université de Montpellier, 34060 Montpellier, France.
- AgroBioSciences, Mohammed VI Polytechnic University, Lot 660-Hay Moulay Rachid, Ben Guerir 43150, Morocco.
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Wordofa GG, Kristensen M. Tolerance and metabolic response of Pseudomonas taiwanensis VLB120 towards biomass hydrolysate-derived inhibitors. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:199. [PMID: 30034525 PMCID: PMC6052574 DOI: 10.1186/s13068-018-1192-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 07/06/2018] [Indexed: 05/10/2023]
Abstract
BACKGROUND Bio-conversion of lignocellulosic biomass to high-value products offers numerous benefits; however, its development is hampered by chemical inhibitors generated during the pretreatment process. A better understanding of how microbes naturally respond to those inhibitors is valuable in the process of designing microorganisms with improved tolerance. Pseudomonas taiwanensis VLB120 is a natively tolerant strain that utilizes a wide range of carbon sources including pentose and hexose sugars. To this end, we investigated the tolerance and metabolic response of P. taiwanensis VLB120 towards biomass hydrolysate-derived inhibitors including organic acids (acetic acid, formic acid, and levulinic acid), furans (furfural, 5-hydroxymethylfurfural), and phenols (vanillin). RESULTS The inhibitory effect of the tested compounds varied with respect to lag phase, specific growth rate, and biomass yield compared to the control cultures grown under the same conditions without addition of inhibitors. However, P. taiwanensis was able to oxidize vanillin and furfural to vanillic acid and 2-furoic acid, respectively. Vanillic acid was further metabolized, whereas 2-furoic acid was secreted outside the cells and remained in the fermentation broth without further conversion. Acetic acid and formic acid were completely consumed from the fermentation broth, while concentration of levulinic acid remained constant throughout the fermentation process. Analysis of free intracellular metabolites revealed varying levels when P. taiwanensis VLB120 was exposed to inhibitory compounds. This resulted in increased levels of ATP to export inhibitors from the cell and NADPH/NADP ratio that provides reducing power to deal with the oxidative stress caused by the inhibitors. Thus, adequate supply of these metabolites is essential for the survival and reproduction of P. taiwanensis in the presence of biomass-derived inhibitors. CONCLUSIONS In this study, the tolerance and metabolic response of P. taiwanensis VLB120 to biomass hydrolysate-derived inhibitors was investigated. P. taiwanensis VLB120 showed high tolerance towards biomass hydrolysate-derived inhibitors compared to most wild-type microbes reported in the literature. It adopts different resistance mechanisms, including detoxification, efflux, and repair, which require additional energy and resources. Thus, targeting redox and energy metabolism in strain engineering may be a successful strategy to overcome inhibition during biomass hydrolysate conversion and lead to development of more robust strains.
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Affiliation(s)
- Gossa G. Wordofa
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Mette Kristensen
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, 2800 Lyngby, Denmark
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Assessment of the detoxification of palm kernel cake hydrolysate for butanol production by Clostridium acetobutylicum YM1. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2018. [DOI: 10.1016/j.bcab.2017.11.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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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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Bu X, Sun L, Shang F, Yan G. Comparative metabolomics profiling of engineered Saccharomyces cerevisiae lead to a strategy that improving β-carotene production by acetate supplementation. PLoS One 2017; 12:e0188385. [PMID: 29161329 PMCID: PMC5697841 DOI: 10.1371/journal.pone.0188385] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 11/06/2017] [Indexed: 12/14/2022] Open
Abstract
A comparative metabolomic analysis was conducted on recombinant Saccharomyces cerevisiae strain producing β-carotene and the parent strain cultivated with glucose as carbon source using gas chromatography-mass spectrometry (GC-MS), high performance liquid chromatography-mass spectrometry (HPLC-MS) and ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) based approach. The results showed that most of the central intermediates associated with amino acids, carbohydrates, glycolysis and TCA cycle intermediates (acetic acid, glycerol, citric acid, pyruvic acid and succinic acid), fatty acids, ergosterol and energy metabolites were produced in a lower amount in recombinant strain, as compared to the parent strain. To increase β-carotene production in recombinant strain, a strategy that exogenous addition of acetate (10 g/l) in exponential phase was developed, which could enhance most intracellular metabolites levels and result in 39.3% and 14.2% improvement of β-carotene concentration and production, respectively, which was accompanied by the enhancement of acetyl-CoA, fatty acids, ergosterol and ATP contents in cells. These results indicated that the amounts of intracellular metabolites in engineered strain are largely consumed by carotenoid formation. Therefore, maintaining intracellular metabolites pool at normal levels is essential for carotenoid biosynthesis. To relieve this limitation, rational supplementation of acetate could be a potential way because it can partially restore the levels of intracellular metabolites and improve the production of carotenoid compounds in recombinant S. cerevisiae.
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Affiliation(s)
- Xiao Bu
- Center for Viticulture and Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, P.R., China
- Key Laboratory of Viticulture and Enology, Ministry of Agriculture, Beijing, P.R., China
| | - Liang Sun
- Center for Viticulture and Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, P.R., China
- Key Laboratory of Viticulture and Enology, Ministry of Agriculture, Beijing, P.R., China
| | - Fei Shang
- Beijing Key Laboratory of Bioprocess, Beijing University of Chemical Technology, Beijing, P.R., China
| | - Guoliang Yan
- Center for Viticulture and Enology, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, P.R., China
- Key Laboratory of Viticulture and Enology, Ministry of Agriculture, Beijing, P.R., China
- * E-mail:
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Al Loman A, Ju LK. Enzyme-based processing of soybean carbohydrate: Recent developments and future prospects. Enzyme Microb Technol 2017; 106:35-47. [PMID: 28859808 DOI: 10.1016/j.enzmictec.2017.06.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 06/15/2017] [Accepted: 06/26/2017] [Indexed: 12/11/2022]
Abstract
Soybean is well known for its high-value oil and protein. Carbohydrate is, however, an underutilized major component, representing almost 26-30% (w/w) of the dried bean. The complex soybean carbohydrate is not easily hydrolyzable and can cause indigestibility when included in food and feed. Enzymes can be used to hydrolyze the carbohydrate for improving soybean processing and value of soybean products. Here the enzyme-based processing developed for the following purposes is reviewed: hydrolysis of different carbohydrate-rich by/products from soybean processing, improvement of soybean oil extraction, and increase of nutritional value of soybean-based food and animal feed. Once hydrolyzed into fermentable sugars, soybean carbohydrate can find more value-added applications and further improve the overall economics of soybean processing.
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Affiliation(s)
- Abdullah Al Loman
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, USA
| | - Lu-Kwang Ju
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325-3906, USA.
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Yeast diversity in relation to the production of fuels and chemicals. Sci Rep 2017; 7:14259. [PMID: 29079838 PMCID: PMC5660169 DOI: 10.1038/s41598-017-14641-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 10/09/2017] [Indexed: 12/27/2022] Open
Abstract
In addition to ethanol, yeasts have the potential to produce many other industrially-relevant chemicals from numerous different carbon sources. However there remains a paucity of information about overall capability across the yeast family tree. Here, 11 diverse species of yeasts with genetic backgrounds representative of different branches of the family tree were investigated. They were compared for their abilities to grow on a range of sugar carbon sources, to produce potential platform chemicals from such substrates and to ferment hydrothermally pretreated rice straw under simultaneous saccharification and fermentation conditions. The yeasts differed considerably in their metabolic capabilities and production of ethanol. A number could produce significant amounts of ethyl acetate, arabinitol, glycerol and acetate in addition to ethanol, including from hitherto unreported carbon sources. They also demonstrated widely differing efficiencies in the fermentation of sugars derived from pre-treated rice straw biomass and differential sensitivities to fermentation inhibitors. A new catabolic property of Rhodotorula mucilaginosa (NCYC 65) was discovered in which sugar substrate is cleaved but the products are not metabolised. We propose that engineering this and some of the other properties discovered in this study and transferring such properties to conventional industrial yeast strains could greatly expand their biotechnological utility.
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Todhanakasem T, Yodsanga S, Sowatad A, Kanokratana P, Thanonkeo P, Champreda V. Inhibition analysis of inhibitors derived from lignocellulose pretreatment on the metabolic activity of Zymomonas mobilis
biofilm and planktonic cells and the proteomic responses. Biotechnol Bioeng 2017; 115:70-81. [DOI: 10.1002/bit.26449] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 08/29/2017] [Accepted: 09/04/2017] [Indexed: 11/07/2022]
Affiliation(s)
- Tatsaporn Todhanakasem
- Department of Agro-Industry; Faculty of Biotechnology; Assumption University; Bangkok Thailand
| | - Supanika Yodsanga
- Department of Agro-Industry; Faculty of Biotechnology; Assumption University; Bangkok Thailand
| | - Apinya Sowatad
- Department of Agro-Industry; Faculty of Biotechnology; Assumption University; Bangkok Thailand
| | - Pattanop Kanokratana
- National Center for Genetic Engineering and Biotechnology (BIOTEC); Pathumthani Thailand
| | | | - Verawat Champreda
- National Center for Genetic Engineering and Biotechnology (BIOTEC); Pathumthani Thailand
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48
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YKL071W from Saccharomyces cerevisiae encodes a novel aldehyde reductase for detoxification of glycolaldehyde and furfural derived from lignocellulose. Appl Microbiol Biotechnol 2017; 101:8405-8418. [DOI: 10.1007/s00253-017-8567-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 09/12/2017] [Accepted: 09/26/2017] [Indexed: 01/24/2023]
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Larragoiti-Kuri J, Rivera-Toledo M, Cocho-Roldán J, Maldonado-Ruiz Esparza K, Le Borgne S, Pedraza-Segura L. Convenient Product Distribution for a Lignocellulosic Biorefinery: Optimization through Sustainable Indexes. Ind Eng Chem Res 2017. [DOI: 10.1021/acs.iecr.7b02101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Javier Larragoiti-Kuri
- Ingeniería
y Ciencias QuímicasUniversidad Autónoma Metropolitana Cuajimalpa, 01120 México City, Mexico
| | - Martín Rivera-Toledo
- Ingeniería
y Ciencias QuímicasUniversidad Autónoma Metropolitana Cuajimalpa, 01120 México City, Mexico
| | - José Cocho-Roldán
- Ingeniería
y Ciencias QuímicasUniversidad Autónoma Metropolitana Cuajimalpa, 01120 México City, Mexico
| | | | - Sylvie Le Borgne
- Chemical
Sciences and Engineering, Universidad Iberoamericana, 01219 México
City, Mexico
| | - Lorena Pedraza-Segura
- Ingeniería
y Ciencias QuímicasUniversidad Autónoma Metropolitana Cuajimalpa, 01120 México City, Mexico
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Two-step economical welan gum production by Sphingomonas sp. HT-1 from sugar industrial by-products. Carbohydr Polym 2017; 181:412-418. [PMID: 29253990 DOI: 10.1016/j.carbpol.2017.09.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 08/29/2017] [Accepted: 09/10/2017] [Indexed: 01/18/2023]
Abstract
A two-step fermentation strategy using glucose mother liquor (GML) for cell growth and xylose mother liquor (XML) for welan gum synthesis was used to alleviate uneconomic welan gum fermentation. This study revealed: (1) optimal initial GML concentration was 11.7g/L (10g/L sugars contained); (2) optimal XML feeding strategy was pseudo-exponential fed-batch and feeding time was 12thh-54thh, amounting to 25.7g/L XML (20g/L sugars contained); and (3) in a 7.5-L bioreactor, welan gum concentration was 22.68±0.50g/L and its yield reached 0.756g/g sugars with trace residual sugars. Compared with the cost of batch fermentation using glucose as sole carbon source, the final carbon source costs decreased by 61.40% and the welan gum yield increased by 50%. GML and XML can be used as inexpensive carbon sources for welan gum production with higher yield, giving them industrial application potential to produce value-added chemicals.
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