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Gaur S, Kaur M, Kalra R, Rene ER, Goel M. Application of microbial resources in biorefineries: Current trend and future prospects. Heliyon 2024; 10:e28615. [PMID: 38628756 PMCID: PMC11019186 DOI: 10.1016/j.heliyon.2024.e28615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 03/21/2024] [Accepted: 03/21/2024] [Indexed: 04/19/2024] Open
Abstract
The recent growing interest in sustainable and alternative sources of energy and bio-based products has driven the paradigm shift to an integrated model termed "biorefinery." Biorefinery framework implements the concepts of novel eco-technologies and eco-efficient processes for the sustainable production of energy and value-added biomolecules. The utilization of microbial resources for the production of various value-added products has been documented in the literatures. However, the appointment of these microbial resources in integrated resource management requires a better understanding of their status. The main of aim of this review is to provide an overview on the defined positioning and overall contribution of the microbial resources, i.e., algae, fungi and bacteria, for various bioprocesses and generation of multiple products from a single biorefinery. By utilizing waste material as a feedstock, biofuels can be generated by microalgae while sequestering environmental carbon and producing value added compounds as by-products. In parallel, fungal biorefineries are prolific producers of lignocellulose degrading enzymes along with pharmaceutically important novel products. Conversely, bacterial biorefineries emerge as a preferred platform for the transformation of standard cells into proficient bio-factories, developing chassis and turbo cells for enhanced target compound production. This comprehensive review is poised to offer an intricate exploration of the current trends, obstacles, and prospective pathways of microbial biorefineries, for the development of future biorefineries.
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Affiliation(s)
- Suchitra Gaur
- Sustainable Agriculture Program, The Energy and Resources Institute, TERI-Gram, Gurugram, 122001, Haryana, India
| | - Mehak Kaur
- Sustainable Agriculture Program, The Energy and Resources Institute, TERI-Gram, Gurugram, 122001, Haryana, India
| | - Rishu Kalra
- Sustainable Agriculture Program, The Energy and Resources Institute, TERI-Gram, Gurugram, 122001, Haryana, India
| | - Eldon R. Rene
- Department of Water Supply, Sanitation and Environmental Engineering, IHE Delft Institute for Water Education, Westvest 7, Delft, 2601DA, the Netherlands
| | - Mayurika Goel
- Sustainable Agriculture Program, The Energy and Resources Institute, TERI-Gram, Gurugram, 122001, Haryana, India
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Laubach JM, Sani RK. 5-Fluorouracil-Encapsulated Films Using Exopolysaccharides from a Thermophilic Bacterium Geobacillus sp. WSUCF1 for Topical Drug Delivery. MICROMACHINES 2023; 14:mi14051092. [PMID: 37241716 DOI: 10.3390/mi14051092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/10/2023] [Accepted: 05/20/2023] [Indexed: 05/28/2023]
Abstract
Bacteria are capable of producing a specific type of biopolymer, termed exopolysaccharides (EPSs). EPSs from thermophile Geobacillus sp. strain WSUCF1 specifically can be assembled using cost-effective lignocellulosic biomass as the primary carbon substrate in lieu of traditional sugars. 5-fluorouracil (5-FU) is an FDA-approved, versatile chemotherapeutic that has yielded high efficacy against colon, rectum, and breast cancers. The present study investigates the feasibility of a 5% 5-fluorouracil film using thermophilic exopolysaccharides as the foundation in conjunction with a simple self-forming method. The drug-loaded film formulation was seen to be highly effective against A375 human malignant melanoma at its current concentration with viability of A375 dropping to 12% after six hours of treatment. A drug release profile revealed a slight burst release before it settled into an extended and maintained release of 5-FU. These initial findings provide evidence for the versatility of thermophilic exopolysaccharides produced from lignocellulosic biomass to act as a chemotherapeutic-delivering device and expand the overall applications of extremophilic EPSs.
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Affiliation(s)
- Joseph M Laubach
- Department of Biomedical Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
| | - Rajesh K Sani
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
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3
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Haque S, Singh R, Pal DB, Faidah H, Ashgar SS, Areeshi MY, Almalki AH, Verma B, Srivastava N, Gupta VK. Thermophilic biohydrogen production strategy using agro industrial wastes: Current update, challenges, and sustainable solutions. CHEMOSPHERE 2022; 307:136120. [PMID: 35995181 DOI: 10.1016/j.chemosphere.2022.136120] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 07/31/2022] [Accepted: 08/16/2022] [Indexed: 06/15/2023]
Abstract
Continuously increasing wastes management issues and the high demand of fuels to fulfill the current societal requirements is not satisfactory. In addition, severe environmental pollution caused by generated wastes and the massive consumption of fossil fuels are the main causes of global warming. In this scenario, production of hydrogen from organic wastes is a potential and one of the most feasible alternatives to resolve these issues. However, sensitivity of H2 production at higher temperature and lack of potential substrates are the main issues which are strongly associated with such kinds of biofuels. Therefore, the present review is targeted towards the evaluation and enhancement of thermophilic biohydrogen production using organic, cellulosic wastes as promising bioresources. This review discusses about the current status, development in the area of thermophilic biohydrogen production wherein organic wastes as key substrate are being employed. The combinations of suitable organic and cellulose rich substrates, thermo-tolerant microbes, high enzymes stability may support to enhance the biohydrogen production, significantly. Further, various factors which may significantly contribute to enhance biohydrogen production have been discussed thoroughly in reference to the thermophilic biohydrogen production technology. Additionally, existing obstacles such as unfavorable thermophilic biohydrogen pathways, inefficiency of thermophilic microbiomes, genetic modifications, enzymes stability have been discussed in context to the possible limitations of thermophilic biohydrogen production strategy. Structural and functional microbiome analysis, fermentation pathway modifications via genetic engineering and the application of nanotechnology to enhance the thermophilic biohydrogen production have been discussed as the future prospective.
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Affiliation(s)
- Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing and Allied Health Sciences, Jazan University, Jazan, 45142, Saudi Arabia
| | - Rajeev Singh
- Department of Environmental Studies, Satyawati College, University of Delhi, Delhi, 110052, India
| | - Dan Bahadur Pal
- Department of Chemical Engineering, Birla Institute of Technology, Mesra Ranchi, 835215, Jharkhand, India; Department of Chemical Engineering, Harcourt Butler Technical University, Nawabganj, Kanpur, 208002, Uttar Pradesh, India
| | - Hani Faidah
- Department of Microbiology, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Sami S Ashgar
- Department of Microbiology, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Mohammed Y Areeshi
- Research and Scientific Studies Unit, College of Nursing and Allied Health Sciences, Jazan University, Jazan, 45142, Saudi Arabia; Medical Laboratory Technology Department, College of Applied Medical Sciences, Jazan University, Jazan, 45142, Saudi Arabia
| | - Atiah H Almalki
- Department of Pharmaceutical Chemistry, College of Pharmacy, Taif University, P.O. Box 11099, Taif, 21944, Saudi Arabia; Addiction and Neuroscience Research Unit, College of Pharmacy, Taif University, Al-Hawiah, Taif, 21944, Saudi Arabia
| | - Bhawna Verma
- Department of Chemical Engineering & Technology, Indian Institute of Technology (BHU) Varanasi Varanasi, 221005, Uttar Pradesh, India
| | - Neha Srivastava
- Department of Chemical Engineering & Technology, Indian Institute of Technology (BHU) Varanasi Varanasi, 221005, Uttar Pradesh, India.
| | - Vijai Kumar Gupta
- Biorefining and Advanced Materials Research Center, Scotland's Rural College (SRUC), Kings Buildings, West Mains Road, Edinburgh, EH9 3JG, UK; Center for Safe and Improved Food, Scotland's Rural College (SRUC), Kings Buildings, West Mains Road, Edinburgh, EH9 3JG, UK.
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Ma L, Wang X, Zhou J, Lü X. Degradation of switchgrass by Bacillus subtilis 1AJ3 and expression of a beta-glycoside hydrolase. Front Microbiol 2022; 13:922371. [PMID: 35966659 PMCID: PMC9374367 DOI: 10.3389/fmicb.2022.922371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 07/11/2022] [Indexed: 11/13/2022] Open
Abstract
Increasing demand for carbon neutrality has led to the development of new techniques and modes of low carbon production. The utilization of microbiology to convert low-cost renewable resources into more valuable chemicals is particularly important. Here, we investigated the ability of a cellulolytic bacterium, Bacillus subtilis 1AJ3, in switchgrass lignocellulose degradation. After 5 days of culture with the strain under 37°C, cellulose, xylan, and acid-insoluble lignin degradation rates were 16.13, 14.24, and 13.91%, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis and field emission scanning electron microscopy (FE-SEM) indicated that the lignin and surface of switchgrass were degraded after incubation with the bacterial strain. Strain 1AJ3 can grow well below 60°C, which satisfies the optimum temperature (50°C) condition of most cellulases; subsequent results emphasize that acid-heat incubation conditions increase the reducing sugar content in a wide range of cellulosic biomass degraded by B. subtilis 1AJ3. To obtain more reducing sugars, we focused on β-glycoside hydrolase, which plays an important role in last steps of cellulose degradation to oligosaccharides. A β-glycoside hydrolase (Bgl-16A) was characterized by cloning and expression in Escherichia coli BL21 and further determined to belong to glycoside hydrolase (GH) 16 family. The Bgl-16A had an enzymatic activity of 365.29 ± 10.43 U/mg, and the enzyme's mode of action was explained by molecular docking. Moreover, the critical influence on temperature (50°C) of Bgl-16A also explained the high-efficiency degradation of biomass by strain under acid-heat conditions. In terms of potential applications, both the strain and the recombinant enzyme showed that coffee grounds would be a suitable and valuable substrate. This study provides a new understanding of cellulose degradation by B. subtilis 1AJ3 that both the enzyme action mode and optimum temperature limitation by cellulases could impact the degradation. It also gave new sight to unique advantage utilization in the industrial production of green manufacturing.
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Affiliation(s)
- Lingling Ma
- Science Center for Future Foods, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, China
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Xin Wang
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Xianyang, China
| | - Jingwen Zhou
- Science Center for Future Foods, Jiangnan University, Wuxi, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education and School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xin Lü
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Xianyang, China
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Xia L, Hao Z, Vemuri B, Zhao S, Gadhamshetty V, Kilduff JE. Improving antifouling properties of poly (ether sulfone) UF membranes with hydrophilic coatings of dopamine and poly(2-dimethylamino) ethyl methacrylate salt to enable water reuse. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.120300] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Vemuri B, Handa V, Jawaharraj K, Sani R, Gadhamshetty V. Enhanced biohydrogen production with low graphene oxide content using thermophilic bioreactors. BIORESOURCE TECHNOLOGY 2022; 346:126574. [PMID: 34923081 DOI: 10.1016/j.biortech.2021.126574] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/09/2021] [Accepted: 12/12/2021] [Indexed: 06/14/2023]
Abstract
Modern society envisions hydrogen (H2) fuel to drive the transportation, industrial, and domestic sectors. Here, we explore use of graphene oxide nanoparticles (GO NPs) for greatly enhancing bio-H2 production by a consortium based on Thermoanaerobacterium thermosaccharolyticum spp. Thermophilic batch bioreactors were set up at 60 OC and initial pH of 8.5 to assess the effects of GO NPs supplements on biohydrogen production. Under optimal GO NPs loading of 10 mg/L, the supplemented system yielded ∼ 300% higher H2 yield (6.78 mol H2/mol sucrose) than control. Such an optimized system offered 73% H2 purity and 85% conversion efficiency by promoted the desirable acetate fermentation pathway. Miseq Illumina sequencing tests revealed that the optimal levels of GO NPs did not alter the microbial composition of consortium.
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Affiliation(s)
- Bhuvan Vemuri
- Civil and Environmental Engineering, South Dakota School of Mines and Technology, 501 E Saint Joseph Blvd, Rapid City, SD 57701, USA; BuGReMeDEE Consortium, South Dakota Mines, Rapid City, SD 57701, USA
| | - Vaibhav Handa
- Civil and Environmental Engineering, South Dakota School of Mines and Technology, 501 E Saint Joseph Blvd, Rapid City, SD 57701, USA; 2-Dimensional Materials for Biofilm Engineering Science and Technology (2DBEST) Center, South Dakota School of Mines and Technology, SD 57701, United States
| | - Kalimuthu Jawaharraj
- Civil and Environmental Engineering, South Dakota School of Mines and Technology, 501 E Saint Joseph Blvd, Rapid City, SD 57701, USA; BuGReMeDEE Consortium, South Dakota Mines, Rapid City, SD 57701, USA; 2-Dimensional Materials for Biofilm Engineering Science and Technology (2DBEST) Center, South Dakota School of Mines and Technology, SD 57701, United States; Data-Driven Materials Discovery for Bioengineering Innovation Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD 57701, USA
| | - Rajesh Sani
- BuGReMeDEE Consortium, South Dakota Mines, Rapid City, SD 57701, USA; 2-Dimensional Materials for Biofilm Engineering Science and Technology (2DBEST) Center, South Dakota School of Mines and Technology, SD 57701, United States; Data-Driven Materials Discovery for Bioengineering Innovation Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD 57701, USA; Chemical and Biological Engineering, South Dakota School of Mines and Technology, SD 57701, United States
| | - Venkataramana Gadhamshetty
- Civil and Environmental Engineering, South Dakota School of Mines and Technology, 501 E Saint Joseph Blvd, Rapid City, SD 57701, USA; BuGReMeDEE Consortium, South Dakota Mines, Rapid City, SD 57701, USA; 2-Dimensional Materials for Biofilm Engineering Science and Technology (2DBEST) Center, South Dakota School of Mines and Technology, SD 57701, United States; Data-Driven Materials Discovery for Bioengineering Innovation Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD 57701, USA.
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Chukwuma OB, Rafatullah M, Tajarudin HA, Ismail N. A Review on Bacterial Contribution to Lignocellulose Breakdown into Useful Bio-Products. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:6001. [PMID: 34204975 PMCID: PMC8199887 DOI: 10.3390/ijerph18116001] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/28/2021] [Accepted: 05/28/2021] [Indexed: 12/15/2022]
Abstract
Discovering novel bacterial strains might be the link to unlocking the value in lignocellulosic bio-refinery as we strive to find alternative and cleaner sources of energy. Bacteria display promise in lignocellulolytic breakdown because of their innate ability to adapt and grow under both optimum and extreme conditions. This versatility of bacterial strains is being harnessed, with qualities like adapting to various temperature, aero tolerance, and nutrient availability driving the use of bacteria in bio-refinery studies. Their flexible nature holds exciting promise in biotechnology, but despite recent pointers to a greener edge in the pretreatment of lignocellulose biomass and lignocellulose-driven bioconversion to value-added products, the cost of adoption and subsequent scaling up industrially still pose challenges to their adoption. However, recent studies have seen the use of co-culture, co-digestion, and bioengineering to overcome identified setbacks to using bacterial strains to breakdown lignocellulose into its major polymers and then to useful products ranging from ethanol, enzymes, biodiesel, bioflocculants, and many others. In this review, research on bacteria involved in lignocellulose breakdown is reviewed and summarized to provide background for further research. Future perspectives are explored as bacteria have a role to play in the adoption of greener energy alternatives using lignocellulosic biomass.
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Affiliation(s)
| | - Mohd Rafatullah
- Division of Environmental Technology, School of Industrial Technology, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia; (O.B.C.); (H.A.T.); (N.I.)
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Vemuri B, Xia L, Chilkoor G, Jawaharraj K, Sani RK, Amarnath A, Kilduff J, Gadhamshetty V. Anaerobic wastewater treatment and reuse enabled by thermophilic bioprocessing integrated with a bioelectrochemical/ultrafiltration module. BIORESOURCE TECHNOLOGY 2021; 321:124406. [PMID: 33272823 DOI: 10.1016/j.biortech.2020.124406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/06/2020] [Accepted: 11/07/2020] [Indexed: 06/12/2023]
Abstract
The current study aimed to develop an anaerobic wastewater treatment and reuse module enabled by thermophilic bioprocessing, a microbial fuel cell (MFC) and ultrafiltration (UF) treatment. A previously unexplored consortium based on Thermoanaerobacterium thermosaccharolyticum and Arcobacter sp. was used to remove ~73% of chemical oxygen demand (COD) from wastewater under anaerobic conditions (CODi = 200 mg/L). The subsequent MFC and UF treatment removed the COD remnants to meet the secondary treatment standards and reuse criteria. The energy efficiency of polyethersulfone UF membranes was improved by modifying their surfaces with coatings based on self-polymerized dopamine, mixtures of dopamine and poly(2-dimethylamino) ethyl methacrylate methyl, and dopamine analog norepinephrine. The resulting hydrophilic, anti-fouling layers were found to reduce interactions between rejected species and the membrane surface. Finally, this study presents a comparative treatment performance and energy efficiency of the wastewater treatment and reuse modules arranged in six different configurations.
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Affiliation(s)
- Bhuvan Vemuri
- Civil and Environmental Engineering, South Dakota Mines, Rapid City, SD 57701, USA
| | - Lichao Xia
- Civil and Environmental Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180, USA; School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, 510006, China
| | - Govinda Chilkoor
- Civil and Environmental Engineering, South Dakota Mines, Rapid City, SD 57701, USA
| | - Kalimuthu Jawaharraj
- Civil and Environmental Engineering, South Dakota Mines, Rapid City, SD 57701, USA; BuG ReMeDEE Consortium, South Dakota Mines, Rapid City, SD 57701, USA
| | - Rajesh Kumar Sani
- BuG ReMeDEE Consortium, South Dakota Mines, Rapid City, SD 57701, USA; Department of Biological and Chemical Engineering, South Dakota Mines, Rapid City, SD 57701, USA
| | - Ammi Amarnath
- Energy Efficiency & Demand Response Program, Electric Power Research Institute, 3420 Hillview Avenue, Palo Alto, CA 94304, USA
| | - James Kilduff
- Civil and Environmental Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180, USA
| | - Venkataramana Gadhamshetty
- Civil and Environmental Engineering, South Dakota Mines, Rapid City, SD 57701, USA; BuG ReMeDEE Consortium, South Dakota Mines, Rapid City, SD 57701, USA; 2D-materials for Biofilm Engineering, Science and Technology Center, South Dakota Mines, 501 E. St. Joseph Street, Rapid City, SD 5770, USA.
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Govil T, Saxena P, Samanta D, Singh SS, Kumar S, Salem DR, Sani RK. Adaptive Enrichment of a Thermophilic Bacterial Isolate for Enhanced Enzymatic Activity. Microorganisms 2020; 8:E871. [PMID: 32526936 PMCID: PMC7355623 DOI: 10.3390/microorganisms8060871] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/03/2020] [Accepted: 06/04/2020] [Indexed: 12/28/2022] Open
Abstract
The mimicking of evolution on a laboratory timescale to enhance biocatalyst specificity, substrate utilization activity, and/or product formation, is an effective and well-established approach that does not involve genetic engineering or regulatory details of the microorganism. The present work employed an evolutionary adaptive approach to improve the lignocellulose deconstruction capabilities of the strain by inducing the expression of laccase, a multicopper oxidase, in Geobacillus sp. strain WSUCF1. This bacterium is highly efficient in depolymerizing unprocessed lignocellulose, needing no preprocessing/pretreatment of the biomasses. However, it natively produces low levels of laccase. After 15 rounds of serially adapting this thermophilic strain in the presence of unprocessed corn stover as the selective pressure, we recorded a 20-fold increase in catalytic laccase activity, at 9.23 ± 0.6 U/mL, in an adapted yet stable strain of Geobacillus sp. WSUCF1, compared with the initial laccase production (0.46 ± 0.04 U/mL) obtained with the unadapted strain grown on unprocessed corn stover before optimization. Chemical composition analysis demonstrated that lignin removal by the adapted strain was 22 wt.% compared with 6 wt.% removal by the unadapted strain. These results signify a favorable prospect for fast, cost competitive bulk production of this thermostable enzyme. Also, this work has practical importance, as this fast adaptation of the Geobacillus sp. strain WSUCF1 suggests the possibility of growing industrial quantities of Geobacillus sp. strain WSUCF1 cells as biocatalysts on reasonably inexpensive carbon sources for commercial use. This work is the first application of the adaptive laboratory evolution approach for developing the desired phenotype of enhanced ligninolytic capability in any microbial strain.
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Affiliation(s)
- Tanvi Govil
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA; (T.G.); (D.S.)
- Composite and Nanocomposite Advanced Manufacturing—Biomaterials Center, Rapid City, SD 57701, USA
| | - Priya Saxena
- Department of Biotechnology & Bioinformatics, Jaypee University of Information Technology, Solan, Himachal Pradesh 173215, India; (P.S.); (S.K.)
| | - Dipayan Samanta
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA; (T.G.); (D.S.)
| | - Sindhu Suresh Singh
- Department of Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA;
| | - Sudhir Kumar
- Department of Biotechnology & Bioinformatics, Jaypee University of Information Technology, Solan, Himachal Pradesh 173215, India; (P.S.); (S.K.)
| | - David R. Salem
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA; (T.G.); (D.S.)
- Composite and Nanocomposite Advanced Manufacturing—Biomaterials Center, Rapid City, SD 57701, USA
- Department of Nanoscience and Nanoengineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA;
- Department of Materials and Metallurgical Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
| | - Rajesh K. Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA; (T.G.); (D.S.)
- Composite and Nanocomposite Advanced Manufacturing—Biomaterials Center, Rapid City, SD 57701, USA
- BuG ReMeDEE consortium, Rapid City, SD 57701, USA
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Ma L, Zhao Y, Meng L, Wang X, Yi Y, Shan Y, Liu B, Zhou Y, Lü X. Isolation of Thermostable Lignocellulosic Bacteria From Chicken Manure Compost and a M42 Family Endocellulase Cloning From Geobacillus thermodenitrificans Y7. Front Microbiol 2020; 11:281. [PMID: 32174898 PMCID: PMC7054444 DOI: 10.3389/fmicb.2020.00281] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 02/07/2020] [Indexed: 01/01/2023] Open
Abstract
The composting ecosystem provides a potential resource for finding new microorganisms with the capability for cellulose degradation. In the present study, Congo red method was used for the isolating of thermostable lignocellulose-degrading bacteria from chicken manure compost. A thermophilic strain named as Geobacillus thermodenitrificans Y7 with acid-resident property was successfully isolated and employed to degrade raw switchgrass at 60°C for 5 days, which resulted in the final degradation rates of cellulose, xylan, and acid-insoluble lignin as 18.64, 12.96, and 17.21%, respectively. In addition, GC-MS analysis about aromatic degradation affirm the degradation of lignin by G. thermodenitrificans Y7. Moreover, an endocellulase gene belong to M42 family was successfully cloned from G. thermodenitrificans Y7 and expressed in Escherichia coli BL21. Recombinant enzyme Cel-9 was purified by Ni-NTA column based the His-tag, and the molecular weight determined as 40.4 kDa by SDA-PAGE. The characterization of the enzyme Cel-9 indicated that the maximum enzyme activity was realized at 50°C and pH 8.6 and, Mn2+ could greatly improve the CMCase enzyme activity of Cel-9 at 10 mM, which was followed by Fe2+ and Co2+. Besides, it also found that the β-1,3-1,4, β-1,3, β-1,4, and β-1,6 glucan linkages all could be hydrolyzed by enzyme Cel-9. Finally, during the application of enzyme Cel-9 to switchgrass, the saccharification rates achieved to 1.81 ± 0.04% and 2.65 ± 0.03% for 50 and 100% crude enzyme, respectively. All these results indicated that both the strain G. thermodenitrificans Y7 and the recombinant endocellulase Cel-9 have the potential to be applied to the biomass industry.
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Affiliation(s)
- Lingling Ma
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Yuchun Zhao
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Yangling, China
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Limin Meng
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xin Wang
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Yanglei Yi
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Yuanyuan Shan
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Bianfang Liu
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Yuan Zhou
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Xin Lü
- Laboratory of Bioresources, College of Food Science and Engineering, Northwest A&F University, Yangling, China
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Sun J, Kosaki Y, Watanabe N. Higher load operation by adoption of ethanol fermentation pretreatment on methane fermentation of food waste. BIORESOURCE TECHNOLOGY 2020; 297:122475. [PMID: 31787512 DOI: 10.1016/j.biortech.2019.122475] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 11/18/2019] [Accepted: 11/19/2019] [Indexed: 06/10/2023]
Abstract
The study aims to examine whether ethanol fermentation pretreatment (EP) of food waste can contribute to high load operation on methane fermentation using an anaerobic membrane bioreactor (AnMBR). The hydraulic retention time was reduced stepwise from 20 to 5 days to increase the load by increasing the feeding volume. The corresponding organic loading rate (OLR) ranged from 6.6 to 26.5 g-COD/L/day. The control series (without pretreatment) was operable to an OLR of 8.8 g-COD/L/day versus 26.5 g-COD/L/day for the EP series. In the control series, the major volatile fatty acid (VFA) produced by acidogenesis in the reactor was propionic acid because based on Gibbs free energy variations for the methane conversion, acetic acid conversion was not as easy as from propionic acid as from ethanol in the EP series. EP proved effective in avoiding VFA accumulation and subsequent decreased pH. Therefore, EP significantly improves AnMBR performance.
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Affiliation(s)
- Jin Sun
- Applied Chemistry, Environmental and Biomedical Engineering, Graduate School of Engineering, Osaka Institute of Technology, Ohmiya 5-16-1, Asahi-ku, Osaka 535-8585, Japan.
| | - Yasunori Kosaki
- Department of Environmental Engineering, Osaka Institute of Technology, Ohmiya 5-16-1, Asahi-ku, Osaka 535-8585, Japan
| | - Nobuhisa Watanabe
- Department of Environmental Engineering, Osaka Institute of Technology, Ohmiya 5-16-1, Asahi-ku, Osaka 535-8585, Japan
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12
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Wu J, Dong L, Zhou C, Liu B, Xing D, Feng L, Wu X, Wang Q, Cao G. Enhanced butanol-hydrogen coproduction by Clostridium beijerinckii with biochar as cell's carrier. BIORESOURCE TECHNOLOGY 2019; 294:122141. [PMID: 31539856 DOI: 10.1016/j.biortech.2019.122141] [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: 07/25/2019] [Revised: 09/06/2019] [Accepted: 09/07/2019] [Indexed: 06/10/2023]
Abstract
In this study, the effects of biochar on the fermentation performance of butanol-hydrogen coproduction by Clostridium beijerinckii F-6 were investigated. Results showed that the biochar with rich porous and graphitized structure can significantly promote the coproduction of butanol and hydrogen. The productivity of butanol and hydrogen reached 0.148 g/L/h and 0.299 mmol/L/h with biochar addition which were 20.23% and 48.76% higher than that in control without biochar addition, respectively. Moreover, the whole energy conversion efficiency calculated based on the heat value showed increment from 43.69% to 51.75% with biochar addition. Combined analysis of organic acids accumulation and oxidation-reduction potential fluctuation proved that biochar can regulate reducing power during fermentation and accelerate the conversion of acid phase to solvent phase. Scanning electron microscope images showed that biochar acted as carriers for cells absorption. Confirmation experiment further proved that biochar enhanced the butanol tolerant ability of Clostridium beijerinckii F-6.
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Affiliation(s)
- Jiwen Wu
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Lili Dong
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Chunshuang Zhou
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Bingfeng Liu
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Defeng Xing
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Liping Feng
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Xiukun Wu
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Qi Wang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Guangli Cao
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
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Njokweni SG, Weimer PJ, Warburg L, Botes M, van Zyl WH. Valorisation of the invasive species, Prosopis juliflora, using the carboxylate platform to produce volatile fatty acids. BIORESOURCE TECHNOLOGY 2019; 288:121602. [PMID: 31195362 DOI: 10.1016/j.biortech.2019.121602] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 05/31/2019] [Accepted: 06/02/2019] [Indexed: 06/09/2023]
Abstract
Biomass derived from low-value, high-volume invasive plant species is an attractive, alternative feedstock to produce biofuels and biochemicals. This study aimed to use the carboxylate platform to valorize the invasive leguminous shrub, Prosopis juliflora (Mesquite), by utilizing in vitro rumen fermentations without chemical pretreatment to produce volatile fatty acids. The three fractions of the mesquite: leaves (ProL), stems (ProS) and branches (ProB) were compared regarding chemical composition, neutral detergent fiber (NDF) digestibility at 7 time points and VFA production after 72 h with sugarcane bagasse (SCB) as a reference. NDF digestibility was significantly (P < 0.05) higher in ProL (35.8%) than ProS (30.4%) and ProB (20.9%) compared to SCB (21.9%). VFA concentrations from 20 g biomass L-1 showed significant differences with 8.07, 6.71 and 6.51 g L-1 for ProL, ProS and ProB respectively, while SCB yielded 4.02 g L-1. These concentrations were comparable with other platforms that employ chemically pretreated biomass for VFA production.
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Affiliation(s)
- Sesethu G Njokweni
- Department of Microbiology, University of Stellenbosch, Stellenbosch 7600, South Africa
| | - Paul J Weimer
- Department of Bacteriology, University of Wisconsin, Madison, WI, USA
| | - Lisa Warburg
- Department of Microbiology, University of Stellenbosch, Stellenbosch 7600, South Africa
| | - Marelize Botes
- Department of Microbiology, University of Stellenbosch, Stellenbosch 7600, South Africa.
| | - Willem H van Zyl
- Department of Microbiology, University of Stellenbosch, Stellenbosch 7600, South Africa
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14
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Rai R, Bibra M, Chadha BS, Sani RK. Enhanced hydrolysis of lignocellulosic biomass with doping of a highly thermostable recombinant laccase. Int J Biol Macromol 2019; 137:232-237. [PMID: 31260768 DOI: 10.1016/j.ijbiomac.2019.06.221] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/27/2019] [Accepted: 06/27/2019] [Indexed: 10/26/2022]
Abstract
A highly thermostable laccase from Geobacillus sp. strain WSUCF1 was cloned into Escherichia coli (E. coli) using pRham N-His SUMO expression system. The thermostable laccase with a molecular weight ~30 kDa had a t1/2 (pH 6.0) of 120 h at 50 °C. The homology modelling for laccase structure showed the presence of Cu active centers with His and Cys residues involved in the active site and ligand binding activity of the enzyme, respectively. The Km, Vmax, Kcat and Kcat/Km values of the purified enzyme with ABTS were found to be 0.146 mM, 1.52 U/mg, 1037 s-1 and 7102.7 s-1 mM-1, respectively. The doping of recombinant WSUCF1 laccase to commercial enzyme cocktails Accellerase® 1500 and Cellic CTec2 improved the hydrolysis of untreated, alkali and acid treated corn stover by 1.31-2.28 times and bagasse by 1.32-2.02 times. Further, in-house enzyme cocktails with laccase hydrolyzed untreated, alkali and acid treated bagasse and gave 1.44, 1.1, and 0.92 folds higher sugar, respectively, when compared with Accellerase 1500. The results suggested that thermostable laccase can aid in the improved hydrolysis of lignocellulosic biomass.
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Affiliation(s)
- Rohit Rai
- Department of Microbiology, Guru Nanak Dev University, Amritsar 143005, India; Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA; Department of Medical Laboratory Sciences, Lovely Professional University, Phagwara Road, Jalandhar 144411, India
| | - Mohit Bibra
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA; Green Biologics Inc., Little Falls, MN 56345, USA
| | - B S Chadha
- Department of Microbiology, Guru Nanak Dev University, Amritsar 143005, India
| | - Rajesh K Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA; BuG ReMeDEE Consortium, Rapid City, SD 57701, USA.
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15
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Han H, Ling Z, Khan A, Virk AK, Kulshrestha S, Li X. Improvements of thermophilic enzymes: From genetic modifications to applications. BIORESOURCE TECHNOLOGY 2019; 279:350-361. [PMID: 30755321 DOI: 10.1016/j.biortech.2019.01.087] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/19/2019] [Accepted: 01/21/2019] [Indexed: 06/09/2023]
Abstract
Thermozymes (from thermophiles or hyperthermophiles) offer obvious advantages due to their excellent thermostability, broad pH adaptation, and hydrolysis ability, resulting in diverse industrial applications including food, paper, and textile processing, biofuel production. However, natural thermozymes with low yield and poor adaptability severely hinder their large-scale applications. Extensive studies demonstrated that using genetic modifications such as directed evolution, semi-rational design, and rational design, expression regulations and chemical modifications effectively improved enzyme's yield, thermostability and catalytic efficiency. However, mechanism-based techniques for thermozymes improvements and applications need more attention. In this review, stabilizing mechanisms of thermozymes are summarized for thermozymes improvements, and these improved thermozymes eventually have large-scale industrial applications.
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Affiliation(s)
- Huawen Han
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, Tianshui South Road #222, Lanzhou, Gansu 730000, People's Republic of China
| | - Zhenmin Ling
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, Tianshui South Road #222, Lanzhou, Gansu 730000, People's Republic of China
| | - Aman Khan
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, Tianshui South Road #222, Lanzhou, Gansu 730000, People's Republic of China
| | - Amanpreet Kaur Virk
- Faculty of Applied Sciences and Biotechnology, Shoolini University of Biotechnology and Management Sciences, Bajhol, Solan, Himachal Pradesh 173229, India
| | - Saurabh Kulshrestha
- Faculty of Applied Sciences and Biotechnology, Shoolini University of Biotechnology and Management Sciences, Bajhol, Solan, Himachal Pradesh 173229, India
| | - Xiangkai Li
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Science, Lanzhou University, Tianshui South Road #222, Lanzhou, Gansu 730000, People's Republic of China.
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Kumar S, Dangi AK, Shukla P, Baishya D, Khare SK. Thermozymes: Adaptive strategies and tools for their biotechnological applications. BIORESOURCE TECHNOLOGY 2019; 278:372-382. [PMID: 30709766 DOI: 10.1016/j.biortech.2019.01.088] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/19/2019] [Accepted: 01/21/2019] [Indexed: 05/10/2023]
Abstract
In today's scenario of global climate change, there is a colossal demand for sustainable industrial processes and enzymes from thermophiles. Plausibly, thermozymes are an important toolkit, as they are known to be polyextremophilic in nature. Small genome size and diverse molecular conformational modifications have been implicated in devising adaptive strategies. Besides, the utilization of chemical technology and gene editing attributions according to mechanical necessities are the additional key factor for efficacious bioprocess development. Microbial thermozymes have been extensively used in waste management, biofuel, food, paper, detergent, medicinal and pharmaceutical industries. To understand the strength of enzymes at higher temperatures different models utilize X-ray structures of thermostable proteins, machine learning calculations, neural networks, but unified adaptive measures are yet to be totally comprehended. The present review provides a recent updates on thermozymes and various interdisciplinary applications including the aspects of thermophiles bioengineering utilizing synthetic biology and gene editing tools.
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Affiliation(s)
- Sumit Kumar
- Enzyme and Microbial Biochemistry Laboratory, Department of Chemistry, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Arun K Dangi
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, India
| | - Pratyoosh Shukla
- Enzyme Technology and Protein Bioinformatics Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, India
| | - Debabrat Baishya
- Department of Bioengineering and Technology, Institute of Science and Technology, Gauhati University, Guwahati 781014, Assam, India
| | - Sunil K Khare
- Enzyme and Microbial Biochemistry Laboratory, Department of Chemistry, Indian Institute of Technology Delhi, New Delhi 110016, India.
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17
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Rathinam NK, Bibra M, Salem DR, Sani RK. Thermophiles for biohydrogen production in microbial electrolytic cells. BIORESOURCE TECHNOLOGY 2019; 277:171-178. [PMID: 30679062 DOI: 10.1016/j.biortech.2019.01.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 01/05/2019] [Accepted: 01/07/2019] [Indexed: 06/09/2023]
Abstract
Thermophiles are promising options to use as electrocatalysts for bioelectrochemical applications including microbial electrolysis. They possess several interesting characteristics such as ability to catalyze a broad range of substrates at better rates and over a broad range of operating conditions, and better electrocatalysis/electrogenic activity over mesophiles. However, a very limited number of investigations have been carried out to explore the microbial reactions/pathways and the molecular mechanisms that contribute to better electrocatalysis/electrolysis in thermophiles. Here, we review the electroactive characteristics of thermophiles, their electron transfer mechanisms, and molecular insights behind the choice of thermophiles for bioelectrochemical/electrolytic processes.
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Affiliation(s)
- Navanietha Krishnaraj Rathinam
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City 57701, USA; BuG ReMeDEE Consortia, South Dakota School of Mines and Technology, Rapid City, SD, USA; Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD 57701, USA.
| | - Mohit Bibra
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City 57701, USA
| | - David R Salem
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City 57701, USA; Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD 57701, USA
| | - Rajesh K Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City 57701, USA; BuG ReMeDEE Consortia, South Dakota School of Mines and Technology, Rapid City, SD, USA; Department of Chemistry and Applied Biological Sciences, South Dakota School of Mines and Technology, Rapid City 57701, USA; Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD 57701, USA
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18
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Wang J, Goh KM, Salem DR, Sani RK. Genome analysis of a thermophilic exopolysaccharide-producing bacterium - Geobacillus sp. WSUCF1. Sci Rep 2019; 9:1608. [PMID: 30733471 PMCID: PMC6367360 DOI: 10.1038/s41598-018-36983-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 11/16/2018] [Indexed: 11/23/2022] Open
Abstract
Geobacillus sp. WSUCF1 is a Gram-positive, spore-forming, aerobic and thermophilic bacterium, isolated from a soil sample obtained from a compost facility. Strain WSUCF1 demonstrated EPS producing capability using different sugars as the carbon source. The whole-genome analysis of WSUCF1 was performed to disclose the essential genes correlated with nucleotide sugar precursor biosynthesis, assembly of monosaccharide units, export of the polysaccharide chain, and regulation of EPS production. Both the biosynthesis pathway and export mechanism of EPS were proposed based on functional annotation. Additionally, the genome description of strain WSUCF1 suggests sophisticated systems for its adaptation under thermophilic conditions. The presence of genes associated with CRISPR-Cas system, quorum quenching lactonase, polyketide synthesis and arsenic resistance makes this strain a potential candidate for various applications in biotechnology and biomedicine. The present study indicates that strain WSUCF1 has promise as a thermophilic EPS producer for a broad range of industrial applications. To the best of our knowledge, this is the first report on genome analysis of a thermophilic Geobacillus species focusing on its EPS biosynthesis and transportation, which will likely pave the way for both enhanced yield and tailor-made EPS production by thermophilic bacteria.
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Affiliation(s)
- Jia Wang
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA
| | - Kian Mau Goh
- Faculty of Science, Universiti Teknologi Malaysia, Skudai, Johor, 81300, Malaysia
| | - David R Salem
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
- Department of Materials and Metallurgical Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
- Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD, 57701, USA.
| | - Rajesh K Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
- Composite and Nanocomposite Advanced Manufacturing - Biomaterials Center (CNAM-Bio Center), Rapid City, SD, 57701, USA.
- BuG ReMeDEE Consortium, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
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Thermostable Xylanase Production by Geobacillus sp. Strain DUSELR13, and Its Application in Ethanol Production with Lignocellulosic Biomass. Microorganisms 2018; 6:microorganisms6030093. [PMID: 30189618 PMCID: PMC6164562 DOI: 10.3390/microorganisms6030093] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 08/29/2018] [Accepted: 08/31/2018] [Indexed: 01/11/2023] Open
Abstract
The aim of the current study was to optimize the production of xylanase, and its application for ethanol production using the lignocellulosic biomass. A highly thermostable crude xylanase was obtained from the Geobacillus sp. strain DUSELR13 isolated from the deep biosphere of Homestake gold mine, Lead, SD. Geobacillus sp. strain DUSELR13 produced 6 U/mL of the xylanase with the beechwood xylan. The xylanase production was improved following the optimization studies, with one factor at a time approach, from 6 U/mL to 19.8 U/mL with xylan. The statistical optimization with response surface methodology further increased the production to 31 U/mL. The characterization studies revealed that the crude xylanase complex had an optimum pH of 7.0, with a broad pH range of 5.0⁻9.0, and an optimum temperature of 75 °C. The ~45 kDa xylanase protein was highly thermostable with t1/2 of 48, 38, and 13 days at 50, 60, and 70 °C, respectively. The xylanase activity increased with the addition of Cu+2, Zn+2, K+, and Fe+2 at 1 mM concentration, and Ca+2, Zn+2, Mg+2, and Na⁺ at 10 mM concentration. The comparative analysis of the crude xylanase against its commercial counterpart Novozymes Cellic HTec and Dupont, Accellerase XY, showed that it performed better at higher temperature, hydrolyzing 65.4% of the beechwood at 75 °C. The DUSEL R13 showed the mettle to hydrolyze, and utilize the pretreated, and untreated lignocellulosic biomass: prairie cord grass (PCG), and corn stover (CS) as the substrate, and gave a maximum yield of 20.5 U/mL with the untreated PCG. When grown in co-culture with Geobacillus thermoglucosidasius, it produced 3.53 and 3.72 g/L ethanol, respectively with PCG, and CS. With these characteristics the xylanase under study could be an industrial success for the high temperature bioprocesses.
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Thermophilic Anaerobic Digestion: Enhanced and Sustainable Methane Production from Co-Digestion of Food and Lignocellulosic Wastes. ENERGIES 2018. [DOI: 10.3390/en11082058] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This article aims to study the codigestion of food waste (FW) and three different lignocellulosic wastes (LW) (Corn stover (CS), Prairie cordgrass (PCG), and Unbleached paper (UBP)) for thermophilic anaerobic digestion to overcome the limitations of digesting food waste alone (volatile fatty acids accumulation and low C:N ratio). Using an enriched thermophilic methanogenic consortium, all the food and lignocellulosic waste mixtures showed positive synergistic effects of codigestion. After 30 days of incubation at 60 °C (100 rpm), the highest methane yield of 305.45 L·kg−1 volatile solids (VS) was achieved with a combination of FW-PCG-CS followed by 279.31 L·kg−1 VS with a mixture of FW-PCG. The corresponding volatile solids reduction for these two co-digestion mixtures was 68% and 58%, respectively. This study demonstrated a reduced hydraulic retention time for methane production using FW and LW.
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