1
|
Amabile C, Abate T, Muñoz R, Chianese S, Musmarra D. Production of poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from methane and volatile fatty acids: properties, metabolic routes and current trend. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:172138. [PMID: 38582106 DOI: 10.1016/j.scitotenv.2024.172138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 03/21/2024] [Accepted: 03/30/2024] [Indexed: 04/08/2024]
Abstract
Polyhydroxyalkanoates (PHAs) are biobased and biodegradable polymers that could effectively replace fossil-based and non-biodegradable plastics. However, their production is currently limited by the high production costs, mainly due to the costly carbon sources used, low productivity and quality of the materials produced. A potential solution lies in utilizing cheap and renewable carbon sources as the primary feedstock during the biological production of PHAs, paving the way for a completely sustainable and economically viable process. In this review, the opportunities and challenges related to the production of polyhydroxyalkanoates using methane and volatile fatty acids (VFAs) as substrates were explored, with a focus on poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate). The discussion reports the current knowledge about promising Type II methanotrophs, the impact of process parameters such as limiting nutrients, CH4:O2 ratio and temperature, the type of co-substrate and its concentration. Additionally, the strategies developed until now to enhance PHA production yields were also discussed.
Collapse
Affiliation(s)
- Claudia Amabile
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031 Aversa, Italy; Institute of Sustainable Processes, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain
| | - Teresa Abate
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031 Aversa, Italy; Institute of Sustainable Processes, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain
| | - Raul Muñoz
- Institute of Sustainable Processes, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain
| | - Simeone Chianese
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031 Aversa, Italy.
| | - Dino Musmarra
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031 Aversa, Italy
| |
Collapse
|
2
|
Eam H, Ko D, Lee C, Myung J. Methylosinus trichosporium OB3b bioaugmentation unleashes polyhydroxybutyrate-accumulating potential in waste-activated sludge. Microb Cell Fact 2024; 23:160. [PMID: 38822346 PMCID: PMC11140957 DOI: 10.1186/s12934-024-02442-w] [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: 01/29/2024] [Accepted: 05/27/2024] [Indexed: 06/02/2024] Open
Abstract
BACKGROUND Wastewater treatment plants contribute approximately 6% of anthropogenic methane emissions. Methanotrophs, capable of converting methane into polyhydroxybutyrate (PHB), offer a promising solution for utilizing methane as a carbon source, using activated sludge as a seed culture for PHB production. However, maintaining and enriching PHB-accumulating methanotrophic communities poses challenges. RESULTS This study investigated the potential of Methylosinus trichosporium OB3b to bioaugment PHB-accumulating methanotrophic consortium within activated sludge to enhance PHB production. Waste-activated sludges with varying ratios of M. trichosporium OB3b (1:0, 1:1, 1:4, and 0:1) were cultivated. The results revealed substantial growth and methane consumption in waste-activated sludge with M. trichosporium OB3b-amended cultures, particularly in a 1:1 ratio. Enhanced PHB accumulation, reaching 37.1% in the same ratio culture, indicates the dominance of Type II methanotrophs. Quantification of methanotrophs by digital polymerase chain reaction showed gradual increases in Type II methanotrophs, correlating with increased PHB production. However, while initial bioaugmentation of M. trichosporium OB3b was observed, its presence decreased in subsequent cycles, indicating the dominance of other Type II methanotrophs. Microbial community analysis highlighted the successful enrichment of Type II methanotrophs-dominated cultures due to the addition of M. trichosporium OB3b, outcompeting Type I methanotrophs. Methylocystis and Methylophilus spp. were the most abundant in M. trichosporium OB3b-amended cultures. CONCLUSIONS Bioaugmentation strategies, leveraging M. trichosporium OB3b could significantly enhance PHB production and foster the enrichment of PHB-accumulating methanotrophs in activated sludge. These findings contribute to integrating PHB production in wastewater treatment plants, providing a sustainable solution for resource recovery.
Collapse
Affiliation(s)
- Hyerim Eam
- Department of Civil and Environmental Engineering, KAIST, Daejeon, 34141, Republic of Korea
| | - Dayoung Ko
- Department of Civil, Urban, Earth, and Environmental Engineering, UNIST, Ulsan, 44919, Republic of Korea
| | - Changsoo Lee
- Department of Civil, Urban, Earth, and Environmental Engineering, UNIST, Ulsan, 44919, Republic of Korea
| | - Jaewook Myung
- Department of Civil and Environmental Engineering, KAIST, Daejeon, 34141, Republic of Korea.
| |
Collapse
|
3
|
Kim Y, Flinkstrom Z, Candry P, Winkler MKH, Myung J. Resource availability governs polyhydroxyalkanoate (PHA) accumulation and diversity of methanotrophic enrichments from wetlands. Front Bioeng Biotechnol 2023; 11:1210392. [PMID: 37588137 PMCID: PMC10425282 DOI: 10.3389/fbioe.2023.1210392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 07/12/2023] [Indexed: 08/18/2023] Open
Abstract
Aquatic environments account for half of global CH4 emissions, with freshwater wetlands being the most significant contributors. These CH4 fluxes can be partially offset by aerobic CH4 oxidation driven by methanotrophs. Additionally, some methanotrophs can convert CH4 into polyhydroxyalkanoate (PHA), an energy storage molecule as well as a promising bioplastic polymer. In this study, we investigate how PHA-accumulating methanotrophic communities enriched from wetlands were shaped by varying resource availability (i.e., C and N concentrations) at a fixed C/N ratio. Cell yields, PHA accumulation, and community composition were evaluated in high (20% CH4 and 10 mM NH4 +) and low resource (0.2% CH4 and 0.1 mM NH4 +) conditions simulating engineered and environmental settings, respectively. High resource availability decreased C-based cell yields, while N-based cell yields remained stable, suggesting nutrient exchange patterns differed between methanotrophic communities at different resource concentrations. PHA accumulation was only observed in high resource enrichments, producing approximately 12.6% ± 2.4% (m/m) PHA, while PHA in low resource enrichments remained below detection. High resource enrichments were dominated by Methylocystis methanotrophs, while low resource enrichments remained significantly more diverse and contained only a minor population of methanotrophs. This study demonstrates that resource concentration shapes PHA-accumulating methanotrophic communities. Together, this provides useful information to leverage such communities in engineering settings as well as to begin understanding their role in the environment.
Collapse
Affiliation(s)
- Yujin Kim
- Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Zachary Flinkstrom
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, United States
| | - Pieter Candry
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, United States
| | - Mari-Karoliina H. Winkler
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, United States
| | - Jaewook Myung
- Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| |
Collapse
|
4
|
Ashoor S, Jun SH, Ko HD, Lee J, Hamelin J, Milferstedt K, Na JG. Polyhydroxybutyrate Production from Methane and Carbon Dioxide by a Syntrophic Consortium of Methanotrophs with Oxygenic Photogranules without an External Oxygen Supply. Microorganisms 2023; 11:1110. [PMID: 37317084 DOI: 10.3390/microorganisms11051110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 04/16/2023] [Accepted: 04/22/2023] [Indexed: 06/16/2023] Open
Abstract
Here, a syntrophic process was developed to produce polyhydroxy-β-butyrate (PHB) from a gas stream containing CH4 and CO2 without an external oxygen supply using a combination of methanotrophs with the community of oxygenic photogranules (OPGs). The co-culture features of Methylomonas sp. DH-1 and Methylosinus trichosporium OB3b were evaluated under carbon-rich and carbon-lean conditions. The critical role of O2 in the syntrophy was confirmed through the sequencing of 16S rRNA gene fragments. Based on their carbon consumption rates and the adaptation to a poor environment, M. trichosporium OB3b with OPGs was selected for methane conversion and PHB production. Nitrogen limitation stimulated PHB accumulation in the methanotroph but hindered the growth of the syntrophic consortium. At 2.9 mM of the nitrogen source, 1.13 g/L of biomass and 83.0 mg/L of PHB could be obtained from simulated biogas. These results demonstrate that syntrophy has the potential to convert greenhouse gases into valuable products efficiently.
Collapse
Affiliation(s)
- Selim Ashoor
- Department of Agricultural Microbiology, Faculty of Agriculture, Ain Shams University, Hadayek Shoubra, Cairo 11241, Egypt
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
| | - Seong-Hoon Jun
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
| | - Han Do Ko
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
| | - Jinwon Lee
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
| | - Jérôme Hamelin
- INRAE, University of Montpellier, LBE, 102 Avenue des Etangs, 11100 Narbonne, France
| | - Kim Milferstedt
- INRAE, University of Montpellier, LBE, 102 Avenue des Etangs, 11100 Narbonne, France
| | - Jeong-Geol Na
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
| |
Collapse
|
5
|
Mrudulakumari Vasudevan U, Mai DHA, Krishna S, Lee EY. Methanotrophs as a reservoir for bioactive secondary metabolites: Pitfalls, insights and promises. Biotechnol Adv 2023; 63:108097. [PMID: 36634856 DOI: 10.1016/j.biotechadv.2023.108097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/10/2022] [Accepted: 01/06/2023] [Indexed: 01/11/2023]
Abstract
Methanotrophs are potent natural producers of several bioactive secondary metabolites (SMs) including isoprenoids, polymers, peptides, and vitamins. Cryptic biosynthetic gene clusters identified from these microbes via genome mining hinted at the vast and hidden SM biosynthetic potential of these microbes. Central carbon metabolism in methanotrophs offers rare pathway intermediate pools that could be further diversified using advanced synthetic biology tools to produce valuable SMs; for example, plant polyketides, rare carotenoids, and fatty acid-derived SMs. Recent advances in pathway reconstruction and production of isoprenoids, squalene, ectoine, polyhydroxyalkanoate copolymer, cadaverine, indigo, and shinorine serve as proof-of-concept. This review provides theoretical guidance for developing methanotrophs as microbial chassis for high-value SMs. We summarize the distinct secondary metabolic potentials of type I and type II methanotrophs, with specific attention to products relevant to biomedical applications. This review also includes native and non-native SMs from methanotrophs, their therapeutic potential, strategies to induce silent biosynthetic gene clusters, and challenges.
Collapse
Affiliation(s)
- Ushasree Mrudulakumari Vasudevan
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Dung Hoang Anh Mai
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Shyam Krishna
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Eun Yeol Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea.
| |
Collapse
|
6
|
Loria MH, Griffin JS, Wells GF, Rhoads KR. Effects of feast-famine nutrient regimes on wastewater algal biofuel communities. PLoS One 2023; 18:e0279943. [PMID: 36598899 DOI: 10.1371/journal.pone.0279943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 12/16/2022] [Indexed: 01/05/2023] Open
Abstract
Microalgae accumulate lipids in response to nutrient deprivation, and these lipids are a biodiesel fuel stock. Algal cultivation with secondary wastewater effluent is one proposed platform for biofuel production, which provides nutrients to algae while further polishing wastewater effluent. Algal bioreactors were tested using a feast-famine feeding regiment in simulated secondary wastewater effluent to evaluate the effects on lipid content and algal community structure. Algal polycultures were inoculated into reactors fed with synthetic secondary wastewater effluent at pH 7.5 and 9 and operated under a feast-famine nutrient (N, P, and BOD) supply regime in sequencing batch reactors. Fatty acid methyl ester contents of the reactors were assessed, which showed a decrease in lipid content after the feast-famine cycling (from 12.2% initially to 5.2% after four cycles at pH 9). This decrease in lipid content was not correlated with an increase in carbohydrate storage within biomass, nor an increase in bacterial biomass abundance relative to algal biomass in the reactors. The eukaryotic microbial communities from reactors operated at pH 9 diverged from reactors operated at pH 7.5 during cycling, with the pH 9 reactors becoming dominated by a single Operational Taxonomic Unit aligning to the Scenedesmus genus. These results suggest that high pH and feast-famine nutrient cycling may select for a less diverse algal community with a lower lipid content within a secondary wastewater polishing scheme.
Collapse
Affiliation(s)
- Mark H Loria
- Department of Civil and Environmental Engineering, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - James S Griffin
- Department of Civil and Environmental Engineering, Northwestern University, Evanston, Illinois, United States of America
| | - George F Wells
- Department of Civil and Environmental Engineering, Northwestern University, Evanston, Illinois, United States of America
| | - Kurt R Rhoads
- Department of Civil and Environmental Engineering, Case Western Reserve University, Cleveland, Ohio, United States of America
| |
Collapse
|
7
|
Rodríguez Y, García S, Pérez R, Lebrero R, Muñoz R. Optimization of nitrogen feeding strategies for improving polyhydroxybutyrate production from biogas by Methylocystis parvus str. OBBP in a stirred tank reactor. CHEMOSPHERE 2022; 299:134443. [PMID: 35364084 DOI: 10.1016/j.chemosphere.2022.134443] [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: 06/07/2021] [Revised: 03/07/2022] [Accepted: 03/24/2022] [Indexed: 06/14/2023]
Abstract
The design of efficient cultivation strategies to produce bioplastics from biogas is crucial for the implementation of this biorefinery process. In this work, biogas-based polyhydroxybutyrate (PHB) production and CH4 biodegradation performance was investigated for the first time in a stirred tank bioreactor inoculated with Methylocystis parvus str. OBBP. Decreasing nitrogen loading rates in continuous mode and alternating feast:famine regimes of 24 h-cycles, and alternating feast:famine regimes of 24 h:24 h and 24 h:48 h were tested. Continuous N feeding did not support an effective PHB production despite the occurrence of nitrogen limiting conditions. Feast-famine cycles of 24 h:24 h (with 50% stoichiometric nitrogen supply) supported the maximum PHB production (20 g-PHB m-3 d-1) without compromising the CH4-elimination capacity (25 g m-3 h-1) of the system. Feast:famine ratios ≤1:2 entailed the deterioration of process performance at stoichiometric nitrogen inputs ≤60%.
Collapse
Affiliation(s)
- Yadira Rodríguez
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| | - Silvia García
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| | - Rebeca Pérez
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| | - Raquel Lebrero
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| | - Raúl Muñoz
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| |
Collapse
|
8
|
Jo SY, Son J, Sohn YJ, Lim SH, Lee JY, Yoo JI, Park SY, Na JG, Park SJ. A shortcut to carbon-neutral bioplastic production: Recent advances in microbial production of polyhydroxyalkanoates from C1 resources. Int J Biol Macromol 2021; 192:978-998. [PMID: 34656544 DOI: 10.1016/j.ijbiomac.2021.10.066] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/04/2021] [Accepted: 10/09/2021] [Indexed: 12/18/2022]
Abstract
Since the 20th century, plastics that are widely being used in general life and industries are causing enormous plastic waste problems since improperly discarded plastics barely degrade and decompose. Thus, the demand for polyhydroxyalkanoates (PHAs), biodegradable polymers with material properties similar to conventional petroleum-based plastics, has been increased so far. The microbial production of PHAs is an environment-friendly solution for the current plastic crisis, however, the carbon sources for the microbial PHA production is a crucial factor to be considered in terms of carbon-neutrality. One‑carbon (C1) resources, such as methane, carbon monoxide, and carbon dioxide, are greenhouse gases and are abundantly found in nature and industry. C1 resources as the carbon sources for PHA production have a completely closed carbon loop with much advances; i) fast carbon circulation with direct bioconversion process and ii) simple fermentation procedure without sterilization as non-preferable nutrients. This review discusses the biosynthesis of PHAs based on C1 resource utilization by wild-type and metabolically engineered microbial host strains via biorefinery processes.
Collapse
Affiliation(s)
- Seo Young Jo
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Jina Son
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Yu Jung Sohn
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Seo Hyun Lim
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Ji Yeon Lee
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Jee In Yoo
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Se Young Park
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Jeong-Geol Na
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, Republic of Korea.
| | - Si Jae Park
- Department of Chemical Engineering and Materials Science, Graduate Program in System Health Science and Engineering, Ewha Womans University, Seoul, 03760, Republic of Korea.
| |
Collapse
|
9
|
Wang S, Liu Q, Li J, Wang Z. Methane in wastewater treatment plants: status, characteristics, and bioconversion feasibility by methane oxidizing bacteria for high value-added chemicals production and wastewater treatment. WATER RESEARCH 2021; 198:117122. [PMID: 33865027 DOI: 10.1016/j.watres.2021.117122] [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: 12/16/2020] [Revised: 02/23/2021] [Accepted: 04/02/2021] [Indexed: 06/12/2023]
Abstract
Methane is a type of renewable fuel that can generate many types of high value-added chemicals, however, besides heat and power production, there is little methane utilization in most of the wastewater treatment plants (WWTPs) all round the world currently. In this review, the status of methane production performance from WWTPs was firstly investigated. Subsequently, based on the identification and classification of methane oxidizing bacteria (MOB), the key enzymes and metabolic pathway of MOB were presented in depth. Then the production, extraction and purification process of high value-added chemicals, including methanol, ectoine, biofuel, bioplastic, methane protein and extracellular polysaccharides, were introduced in detail, which was conducive to understand the bioconversion process of methane. Finally, the use of methane in wastewater treatment process, including nitrogen removal, emerging contaminants removal as well as resource recovery was extensively explored. These findings could provide guidance in the development of sustainable economy and environment, and facilitate biological methane conversion by using MOB in further attempts.
Collapse
Affiliation(s)
- Shuo Wang
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Engineering Laboratory for Biomass Energy and Carbon Reduction Technology, Wuxi 214122, China; Jiangsu College of Water Treatment Technology and Material Collaborative Innovation Center, Suzhou 215009, China
| | - Qixin Liu
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Ji Li
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Engineering Laboratory for Biomass Energy and Carbon Reduction Technology, Wuxi 214122, China; Jiangsu College of Water Treatment Technology and Material Collaborative Innovation Center, Suzhou 215009, China.
| | - Zhiwu Wang
- Department of Civil and Environmental Engineering, Virginia Tech, Manassas, VA 20110, USA.
| |
Collapse
|
10
|
Bishoff D, AlSayed A, Eldyasti A. Production of poly-hydroxy-butyrate using nitrogen removing methanotrophic mixed culture bioreactor. J Biosci Bioeng 2021; 132:351-358. [PMID: 34045142 DOI: 10.1016/j.jbiosc.2021.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 04/06/2021] [Accepted: 04/17/2021] [Indexed: 10/21/2022]
Abstract
Methanotrophic biotechnologies for methane mitigation and nitrogen removal are becoming more apparent. However, the sludge produced during these processes is often underutilized and instead can be applied for resources recovery. Fortunately, methanotrophic bacteria can utilize methane while also producing poly-hydroxy-butyrate (PHB), bioplastics, under nutrients deficient conditions. Bioplastics are increasing in popularity and can be produced from unexploited resources, such as methane and carbon dioxide, within wastewater facilities. This research demonstrates that methanotrophic sludge generated during a methanotrophic-based nitrogen removal process, which has been recently suggested, can be directly utilized for PHB production. It was found that the PHB storage response of the methanotrophic driven mixed culture was greatest when methane and oxygen were supplied in equal volume to volume ratios. In addition, the PHB response due to imposing feast-like conditions along with nitrogen or phosphorus deprivation were assessed. The highest PHB storage achieved was 21 ± 1.31% after one cycle under methane sufficient and nitrogen limited conditions. Whereas, only applying feast-like conditions demonstrated a PHB storage of 15 ± 0.67% while simultaneously removing nitrate. Finally, further optimization and continued feast- and famine-like cycles can lead to a greater PHB storage response by the culture.
Collapse
Affiliation(s)
- Danelle Bishoff
- Department of Civil Engineering, Lassonde School of Engineering, York University, Toronto, Ontario M3J 1P3, Canada
| | - Ahmed AlSayed
- Department of Civil Engineering, Lassonde School of Engineering, York University, Toronto, Ontario M3J 1P3, Canada
| | - Ahmed Eldyasti
- Department of Civil Engineering, Lassonde School of Engineering, York University, Toronto, Ontario M3J 1P3, Canada.
| |
Collapse
|
11
|
Cui P, Shao Y, Wang Y, Zhao R, Zhan H, Zhong W. Co-production of polyhydroxybutyrate (PHB) and coenzyme Q10 (CoQ10) via no-sugar fermentation—a case by Methylobacterium sp. XJLW. ANN MICROBIOL 2021. [DOI: 10.1186/s13213-021-01632-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Purpose
To explore a competitive PHB-producing fermentation process, this study evaluated the potential for Methylobacterium sp. XJLW to produce simultaneously PHB and coenzyme Q10 (CoQ10) using methanol as sole carbon and energy source.
Methods
The metabolic pathways of PHB and CoQ10 biosynthesis in Methylobacterium sp. XJLW were first mined based on the genomic and comparative transcriptomics information. Then, real-time fluorescence quantitative PCR (RT-qPCR) was employed for comparing the expression level of important genes involved in PHB and CoQ10 synthesis pathways’ response to methanol and glucose. Transmission electron microscope (TEM), gas chromatography/mass spectrometry (GC-MS), nuclear magnetic resonance (NMR), Fourier transformation infrared spectrum (FT-IR), and liquid chromatography/mass spectrometry (LC-MS) methods were used to elucidate the yield and structure of PHB and CoQ10, respectively. PHB and CoQ10 productivity of Methylobacterium sp. XJLW were evaluated in Erlenmeyer flask for medium optimization, and in a 5-L bioreactor for methanol fed-batch strategy according to dissolved oxygen (DO) and pH control.
Results
Comparative genomics analysis showed that the PHB and CoQ10 biosynthesis pathways co-exist in Methylobacterium sp. XJLW. Transcriptomics analysis showed that the transcription level of key genes in both pathways responding to methanol was significantly higher than that responding to glucose. Correspondingly, strain Methylobacterium sp. XJLW can produce PHB and CoQ10 simultaneously with higher yield using cheap and abundant methanol than using glucose as sole carbon and energy source. The isolated products showed the structure characteristics same to that of standard PHB and CoQ10. The optimal medium and cultural conditions for PHB and CoQ10 co-production by Methylobacterium sp. XJLW was in M3 medium containing 7.918 g L-1 methanol, 0.5 g L-1 of ammonium sulfate, 0.1% (v/v) of Tween 80, and 1.0 g L-1 of sodium chloride, under 30 °C and pH 7.0. In a 5-L bioreactor coupled with methanol fed-batch process, a maximum DCW value (46.31 g L-1) with the highest yields of PHB and CoQ10, reaching 6.94 g L-1 and 22.28 mg L-1, respectively.
Conclusion
Methylobacterium sp. XJLW is potential for efficiently co-producing PHB and CoQ10 employing methanol as sole carbon and energy source. However, it is still necessary to further optimize fermentation process, and genetically modify strain pathway, for enhanced production of PHB and CoQ10 simultaneously by Methylobacterium sp. XJLW. It also suggests a potential strategy to develop efficiently co-producing other high-value metabolites using methanol-based bioprocess.
Collapse
|
12
|
Rodríguez Y, Firmino PIM, Pérez V, Lebrero R, Muñoz R. Biogas valorization via continuous polyhydroxybutyrate production by Methylocystis hirsuta in a bubble column bioreactor. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 113:395-403. [PMID: 32585559 DOI: 10.1016/j.wasman.2020.06.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/25/2020] [Accepted: 06/11/2020] [Indexed: 06/11/2023]
Abstract
Creating additional value out of biogas during waste treatment has become a priority in past years. Biogas bioconversion into valuable bioproducts such as biopolymers has emerged as a promising strategy. This work assessed the operational feasibility of a bubble column bioreactor (BCB) implemented with gas recirculation and inoculated with a polyhydroxybutyrate (PHB)-producing strain using biogas as substrate. The BCB was initially operated at empty bed residence times (EBRTs) ranging from 30 to 120 min and gas recirculation ratios (R) from 0 to 30 to assess the gas-to-liquid mass transfer and bioconversion of CH4. Subsequently, the BCB was continuously operated at a R of 30 and an EBRT of 60 min under excess of nitrogen and nitrogen feast-famine cycles of 24 h:24 h to trigger PHB synthesis. Gas recirculation played a major role in CH4 gas-liquid transfer, providing almost fourfold higher CH4 elimination capacities (~41 g CH4 m-3 h-1) at the highest R and EBRT of 60 min. The long-term operation under N excess conditions entailed nitrite accumulation (induced by O2 limiting conditions) and concurrent methanotrophic activity inhibition above ~60 mg N-NO2- L-1. Adjusting the N-NO3- supply to match microbial N demand successfully prevented nitrite accumulation. Finally, the N feast-famine 24 h:24 h strategy supported a stable CH4 conversion with a removal efficiency of 70% along with a continuous PHB production, which yielded PHB accumulations of 14.5 ± 2.9% (mg PHB mg-1 total suspended solids × 100). These outcomes represent the first step towards the integration of biogas biorefineries into conventional anaerobic digestion plants.
Collapse
Affiliation(s)
- Yadira Rodríguez
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Paulo Igor Milen Firmino
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain; Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Víctor Pérez
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raquel Lebrero
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raúl Muñoz
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain; Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain.
| |
Collapse
|
13
|
Wang S, An Z, Wang ZW. Bioconversion of methane to chemicals and fuels by methane-oxidizing bacteria. ADVANCES IN BIOENERGY 2020. [DOI: 10.1016/bs.aibe.2020.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
14
|
Luangthongkam P, Strong PJ, Syed Mahamud SN, Evans P, Jensen P, Tyson G, Laycock B, Lant PA, Pratt S. The effect of methane and odd-chain fatty acids on 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) synthesis by a Methylosinus-dominated mixed culture. BIORESOUR BIOPROCESS 2019. [DOI: 10.1186/s40643-019-0285-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractA methanotrophic community was enriched in a semi-continuous reactor under non-aseptic conditions with methane and ammonia as carbon and nitrogen source. After a year of operation, Methylosinus sp., accounted for 80% relative abundance of the total sequences identified from potential polyhydroxyalkanoates (PHAs) producers, dominated the methane-fed enrichment. Prior to induction of PHA accumulation, cells harvested from the parent reactor contained low level of PHA at 4.0 ± 0.3 wt%. The cells were later incubated in the absence of ammonia with various combinations of methane, propionic acid, and valeric acid to induce biosynthesis of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Previous studies reported that methanotrophic utilization of odd-chain fatty acids for the production of PHAs requires reducing power from methane oxidation. However, our findings demonstrated that the PHB-containing methanotrophic enrichment does not require methane availability to generate 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV)—when odd-chain fatty acids are presented. The enrichment yielded up to 14 wt% PHA with various mole fractions of 3HV monomer depending on the availability of methane and odd-fatty acids. Overall, the addition of valeric acid resulted in a higher PHA content and a higher 3HV fraction. The highest 3HV fraction (up to 65 mol%) was obtained from the methane–valeric acid experiment, which is higher than those previously reported for PHA-producing methanotrophic mixed microbial cultures.
Collapse
|
15
|
Cantera S, Sánchez-Andrea I, Lebrero R, García-Encina PA, Stams AJM, Muñoz R. Multi-production of high added market value metabolites from diluted methane emissions via methanotrophic extremophiles. BIORESOURCE TECHNOLOGY 2018; 267:401-407. [PMID: 30031279 DOI: 10.1016/j.biortech.2018.07.057] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/09/2018] [Accepted: 07/11/2018] [Indexed: 05/12/2023]
Abstract
This study constitutes the first-proof-of-concept of a methane biorefinery based on the multi-production of high profit margin substances (ectoine, hydroxyectoine, polyhydroxyalkanoates (PHAs) and exopolysaccharides (EPS)) using methane as the sole carbon and energy source. Two bubble column bioreactors were operated under different magnesium concentrations (0.2, 0.02 and 0.002 g L-1) to validate and optimize this innovative strategy for valorization of CH4 emissions. High Mg2+ concentrations promoted the accumulation of ectoine (79.7-94.2 mg g biomass-1), together with high hydroxyectoine yields (up to 13 mg g biomass-1) and EPS concentrations (up to 2.6 g L culture broth-1). Unfortunately, PHA synthesis was almost negligible (14.3 mg L-1) and only found at the lowest Mg2+ concentration tested. Halomonas, Marinobacter, Methylophaga and Methylomicrobium, previously described as ectoine producers, were dominant in both bioreactors, Methylomicrobium being the only described methanotroph. This study encourages further research on CH4 biorefineries capable of creating value out of GHG mitigation.
Collapse
Affiliation(s)
- S Cantera
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, Valladolid University, Dr. Mergelina, s/n, Valladolid, Spain
| | - I Sánchez-Andrea
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - R Lebrero
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, Valladolid University, Dr. Mergelina, s/n, Valladolid, Spain
| | - P A García-Encina
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, Valladolid University, Dr. Mergelina, s/n, Valladolid, Spain
| | - Alfons J M Stams
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - R Muñoz
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, Valladolid University, Dr. Mergelina, s/n, Valladolid, Spain.
| |
Collapse
|
16
|
Muñoz R, Soto C, Zuñiga C, Revah S. A systematic comparison of two empirical gas-liquid mass transfer determination methodologies to characterize methane biodegradation in stirred tank bioreactors. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 217:247-252. [PMID: 29605779 DOI: 10.1016/j.jenvman.2018.03.097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/18/2018] [Accepted: 03/22/2018] [Indexed: 05/12/2023]
Abstract
This study aimed at systematically comparing the potential of two empirical methods for the estimation of the volumetric CH4 mass transfer coefficient (klaCH4), namely gassing-out and oxygen transfer rate (OTR), to describe CH4 biodegradation in a fermenter operated with a methanotrophic consortium at 400, 600 and 800 rpm. The klaCH4 estimated from the OTR methodology accurately predicted the CH4 elimination capacity (EC) under CH4 mass transfer limiting conditions regardless of the stirring rate (∼9% of average error between empirical and estimated ECs). Thus, empirical CH4-ECs of 37.8 ± 5.8, 42.5 ± 5.4 and 62.3 ± 5.2 g CH4 m-3 h-1vs predicted CH4-ECs of 35.6 ± 2.2, 50.1 ± 2.3 and 59.6 ± 3.4 g CH4 m-3 h-1 were recorded at 400, 600 and 800 rpm, respectively. The rapid Co2+-catalyzed reaction of O2 with SO3-2 in the vicinity of the gas-liquid interphase during OTR determinations, mimicking microbial CH4 uptake in the biotic experiments, was central to accurately describe the klaCH4.
Collapse
Affiliation(s)
- Raul Muñoz
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Unidad Cuajimalpa, Avenida Vasco de Quiroga 4871, Col. Santa Fe Cuajimalpa. Delegación Cuajimalpa de Morelos, Ciudad de México, Mexico; Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain
| | - Cenit Soto
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Unidad Cuajimalpa, Avenida Vasco de Quiroga 4871, Col. Santa Fe Cuajimalpa. Delegación Cuajimalpa de Morelos, Ciudad de México, Mexico
| | - Cristal Zuñiga
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Unidad Cuajimalpa, Avenida Vasco de Quiroga 4871, Col. Santa Fe Cuajimalpa. Delegación Cuajimalpa de Morelos, Ciudad de México, Mexico
| | - Sergio Revah
- Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Unidad Cuajimalpa, Avenida Vasco de Quiroga 4871, Col. Santa Fe Cuajimalpa. Delegación Cuajimalpa de Morelos, Ciudad de México, Mexico.
| |
Collapse
|
17
|
Rapid isolation of fast-growing methanotrophs from environmental samples using continuous cultivation with gradually increased dilution rates. Appl Microbiol Biotechnol 2018; 102:5707-5715. [PMID: 29736819 DOI: 10.1007/s00253-018-8978-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 03/22/2018] [Accepted: 03/30/2018] [Indexed: 12/29/2022]
Abstract
Methanotrophs have recently gained interest as biocatalysts for mitigation of greenhouse gas emission and conversion of methane to value-added products; however, their slow growth has, at least partially, hindered their industrial application. A rapid isolation technique that specifically screens for the fastest-growing methanotrophs was developed using continuous cultivation with gradually increased dilution rates. Environmental samples collected from methane-rich environments were enriched in continuously stirred tank reactors with unrestricted supply of methane and air. The reactor was started at the dilution rate of 0.1 h-1, and the dilution rates were increased with an increment of 0.05 h-1 until the reactor was completely washed out. The shifts in the overall microbial population and methanotrophic community at each step of the isolation procedure were monitored with 16S rRNA amplicon sequencing. The predominant methanotrophic groups recovered after reactor operations were affiliated to the gammaproteobacterial genera Methylomonas and Methylosarcina. The methanotrophic strains isolated from the reactor samples collected at their respective highest dilution rates exhibited specific growth rates up to 0.40 h-1; the highest value reported for methanotrophs. The novel isolation method developed in this study significantly shortened the time and efforts needed for isolation of methanotrophs from environmental samples and was capable of screening for the methanotrophs with the fastest growth rates.
Collapse
|
18
|
Technologies for the bioconversion of methane into more valuable products. Curr Opin Biotechnol 2018; 50:128-135. [PMID: 29316497 DOI: 10.1016/j.copbio.2017.12.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 12/19/2017] [Accepted: 12/20/2017] [Indexed: 11/22/2022]
Abstract
Methane, with a global warming potential twenty five times higher than that of CO2 is the second most important greenhouse gas emitted nowadays. Its bioconversion into microbial molecules with a high retail value in the industry offers a potential cost-efficient and environmentally friendly solution for mitigating anthropogenic diluted CH4-laden streams. Methane bio-refinery for the production of different compounds such as ectoine, feed proteins, biofuels, bioplastics and polysaccharides, apart from new bioproducts characteristic of methanotrophic bacteria, has been recently tested in discontinuous and continuous bioreactors with promising results. This review constitutes a critical discussion about the state-of-the-art of the potential and research niches of biotechnologies applied in a CH4 biorefinery approach.
Collapse
|
19
|
Draft Genome Sequences of Two Gammaproteobacterial Methanotrophs Isolated from Rice Ecosystems. GENOME ANNOUNCEMENTS 2017; 5:5/33/e00526-17. [PMID: 28818885 PMCID: PMC5604758 DOI: 10.1128/genomea.00526-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The genomes of the aerobic methanotrophs “Methyloterricola oryzae” strain 73aT and Methylomagnum ishizawai strain 175 were sequenced. Both strains were isolated from rice plants. Methyloterricola oryzae strain 73aT represents the first isolate of rice paddy cluster I, and strain 175 is the second representative of the recently described genus Methylomagnum.
Collapse
|
20
|
Chidambarampadmavathy K, Karthikeyan OP, Huerlimann R, Maes GE, Heimann K. Responses of mixed methanotrophic consortia to variable Cu 2+/Fe 2+ ratios. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2017; 197:159-166. [PMID: 28365562 DOI: 10.1016/j.jenvman.2017.03.063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 03/14/2017] [Accepted: 03/21/2017] [Indexed: 05/22/2023]
Abstract
Methane mitigation in landfill top cover soils is mediated by methanotrophs whose optimal methane (CH4) oxidation capacity is governed by environmental and complex microbial community interactions. Optimization of CH4 remediating bio-filters need to take microbial responses into account. Divalent copper (Cu2+) and iron (Fe2+) are present in landfills at variable ratios and play a vital role in methane oxidation capacity and growth of methanotrophs. This study, as a first of its kind, therefore quantified effects of variable Cu2+ and Fe2+ (5:5, 5:25 and 5:50 μM) ratios on mixed methanotrophic communities enriched from landfill top cover (LB) and compost soils (CB). CH4 oxidation capacity, CH4 removal efficiencies, fatty acids content/profiles and polyhydroxybutyrate (PHB; a biopolymer) contents were also analysed to quantify performance and potential co-product development. Mixed methanotroph cultures were raised in 10 L continuous stirred tank reactors (CSTRs, Bioflo® & Celligen® 310 Fermentor/Bioreactor; John Morris Scientific, Chatswood, NSW, Australia). Community structure was determined by amplifying the V3-V4 region of 16s rRNA gene. Community structure and, consequently, fatty acid-profiles changed significantly with increasing Cu2+/Fe2+ ratios, and responses were different for LB and CB. Effects on methane oxidation capacities and PHB content were similar in the LB- and CB-CSTR, decreasing with increasing Cu2+/Fe2+ ratios, while biomass growth was unaffected. In general, high Fe2+ concentration favored growth of the type -II methanotroph Methylosinus in the CB-CSTR, but methanotroph abundances decreased in the LB-CSTR. Increase in Cu2+/Fe2+ ratio increased the growth of Sphingopyxis in both systems, while Azospirllum was co-dominant in the LB- but absent in the CB-CSTR. After 13 days, methane oxidation capacities and PHB content decreased by ∼50% and more in response to increasing Fe2+ concentrations. Although methanotroph abundance was ∼2% in the LB- (compared to >50% in CB-CSTR), methane oxidation capacities were comparable in the two systems, suggesting that methane oxidation capacity was maintained by the dominant Azospirllum and Sphingopyxis in the LB-CSTR. Despite similar methanotroph inoculum community composition and controlled environmental variables, increasing Cu2+/Fe2+ ratios resulted in significantly different microbial community structures in the LB- and CB-CSTR, indicative of complex microbial interactions. In summary, our results suggest that a detailed understanding of allelopathic interactions in mixed methanotrophic consortia is vital for constructing robust bio-filters for CH4 emission abatement.
Collapse
Affiliation(s)
- Karthigeyan Chidambarampadmavathy
- College of Science and Engineering, James Cook University, Townsville 4811, Queensland, Australia; Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville 4811, Queensland, Australia
| | - Obulisamy Parthiba Karthikeyan
- College of Science and Engineering, James Cook University, Townsville 4811, Queensland, Australia; Comparative Genomics Centre, James Cook University, Townsville 4811, Queensland, Australia; Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville 4811, Queensland, Australia; Sino-Forest Applied Research Centre for Pearl River Delta Environment (ARCPE), Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | - Roger Huerlimann
- College of Science and Engineering, James Cook University, Townsville 4811, Queensland, Australia; Comparative Genomics Centre, James Cook University, Townsville 4811, Queensland, Australia; Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville 4811, Queensland, Australia
| | - Gregory E Maes
- College of Science and Engineering, James Cook University, Townsville 4811, Queensland, Australia; Comparative Genomics Centre, James Cook University, Townsville 4811, Queensland, Australia; Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville 4811, Queensland, Australia
| | - Kirsten Heimann
- College of Science and Engineering, James Cook University, Townsville 4811, Queensland, Australia; Comparative Genomics Centre, James Cook University, Townsville 4811, Queensland, Australia; Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville 4811, Queensland, Australia; Centre for Bio-discovery and Molecular Development of Therapeutics, James Cook University, Townsville 4811, Queensland, Australia.
| |
Collapse
|
21
|
Puyol D, Batstone DJ, Hülsen T, Astals S, Peces M, Krömer JO. Resource Recovery from Wastewater by Biological Technologies: Opportunities, Challenges, and Prospects. Front Microbiol 2017; 7:2106. [PMID: 28111567 PMCID: PMC5216025 DOI: 10.3389/fmicb.2016.02106] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 12/13/2016] [Indexed: 01/07/2023] Open
Abstract
Limits in resource availability are driving a change in current societal production systems, changing the focus from residues treatment, such as wastewater treatment, toward resource recovery. Biotechnological processes offer an economic and versatile way to concentrate and transform resources from waste/wastewater into valuable products, which is a prerequisite for the technological development of a cradle-to-cradle bio-based economy. This review identifies emerging technologies that enable resource recovery across the wastewater treatment cycle. As such, bioenergy in the form of biohydrogen (by photo and dark fermentation processes) and biogas (during anaerobic digestion processes) have been classic targets, whereby, direct transformation of lipidic biomass into biodiesel also gained attention. This concept is similar to previous biofuel concepts, but more sustainable, as third generation biofuels and other resources can be produced from waste biomass. The production of high value biopolymers (e.g., for bioplastics manufacturing) from organic acids, hydrogen, and methane is another option for carbon recovery. The recovery of carbon and nutrients can be achieved by organic fertilizer production, or single cell protein generation (depending on the source) which may be utilized as feed, feed additives, next generation fertilizers, or even as probiotics. Additionlly, chemical oxidation-reduction and bioelectrochemical systems can recover inorganics or synthesize organic products beyond the natural microbial metabolism. Anticipating the next generation of wastewater treatment plants driven by biological recovery technologies, this review is focused on the generation and re-synthesis of energetic resources and key resources to be recycled as raw materials in a cradle-to-cradle economy concept.
Collapse
Affiliation(s)
- Daniel Puyol
- Group of Chemical and Environmental Engineering, School of Experimental Sciences and Technology, King Juan Carlos UniversityMostoles, Spain
| | - Damien J. Batstone
- Advanced Water Management Centre, University of Queensland, BrisbaneQLD, Australia
- CRC for Water Sensitive Cities, ClaytonVIC, Australia
| | - Tim Hülsen
- Advanced Water Management Centre, University of Queensland, BrisbaneQLD, Australia
- CRC for Water Sensitive Cities, ClaytonVIC, Australia
| | - Sergi Astals
- Advanced Water Management Centre, University of Queensland, BrisbaneQLD, Australia
| | - Miriam Peces
- Centre for Solid Waste Bioprocessing, School of Civil Engineering, University of Queensland, BrisbaneQLD, Australia
| | - Jens O. Krömer
- Advanced Water Management Centre, University of Queensland, BrisbaneQLD, Australia
- Centre for Microbial Electrochemical Systems, University of Queensland, BrisbaneQLD, Australia
| |
Collapse
|
22
|
Fernandez-Gonzalez N, Huber JA, Vallino JJ. Microbial Communities Are Well Adapted to Disturbances in Energy Input. mSystems 2016; 1:e00117-16. [PMID: 27822558 PMCID: PMC5080406 DOI: 10.1128/msystems.00117-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 08/16/2016] [Indexed: 11/20/2022] Open
Abstract
Although microbial systems are well suited for studying concepts in ecological theory, little is known about how microbial communities respond to long-term periodic perturbations beyond diel oscillations. Taking advantage of an ongoing microcosm experiment, we studied how methanotrophic microbial communities adapted to disturbances in energy input over a 20-day cycle period. Sequencing of bacterial 16S rRNA genes together with quantification of microbial abundance and ecosystem function were used to explore the long-term dynamics (510 days) of methanotrophic communities under continuous versus cyclic chemical energy supply. We observed that microbial communities appeared inherently well adapted to disturbances in energy input and that changes in community structure in both treatments were more dependent on internal dynamics than on external forcing. The results also showed that the rare biosphere was critical to seeding the internal community dynamics, perhaps due to cross-feeding or other strategies. We conclude that in our experimental system, internal feedbacks were more important than external drivers in shaping the community dynamics over time, suggesting that ecosystems can maintain their function despite inherently unstable community dynamics. IMPORTANCE Within the broader ecological context, biological communities are often viewed as stable and as only experiencing succession or replacement when subject to external perturbations, such as changes in food availability or the introduction of exotic species. Our findings indicate that microbial communities can exhibit strong internal dynamics that may be more important in shaping community succession than external drivers. Dynamic "unstable" communities may be important for ecosystem functional stability, with rare organisms playing an important role in community restructuring. Understanding the mechanisms responsible for internal community dynamics will certainly be required for understanding and manipulating microbiomes in both host-associated and natural ecosystems.
Collapse
Affiliation(s)
| | - Julie A. Huber
- The Josephine Bay Paul Center, Marine Biological Laboratory, Woods Hole, Massachusetts, USA
| | - Joseph J. Vallino
- Ecosystems Center, Marine Biological Laboratory, Woods Hole, Massachusetts, USA
| |
Collapse
|
23
|
Enrichment and characteristics of mixed methane-oxidizing bacteria from a Chinese coal mine. Appl Microbiol Biotechnol 2016; 100:10331-10341. [DOI: 10.1007/s00253-016-7738-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 07/11/2016] [Accepted: 07/13/2016] [Indexed: 10/21/2022]
|
24
|
Jiang H, Duan C, Jiang P, Liu M, Luo M, Xing XH. Characteristics of scale-up fermentation of mixed methane-oxidizing bacteria. Biochem Eng J 2016. [DOI: 10.1016/j.bej.2015.12.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
25
|
Myung J, Flanagan JC, Waymouth RM, Criddle CS. Methane or methanol-oxidation dependent synthesis of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) by obligate type II methanotrophs. Process Biochem 2016. [DOI: 10.1016/j.procbio.2016.02.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
26
|
Strong PJ, Laycock B, Mahamud SNS, Jensen PD, Lant PA, Tyson G, Pratt S. The Opportunity for High-Performance Biomaterials from Methane. Microorganisms 2016; 4:E11. [PMID: 27681905 PMCID: PMC5029516 DOI: 10.3390/microorganisms4010011] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/15/2016] [Accepted: 01/22/2016] [Indexed: 01/18/2023] Open
Abstract
Polyhydroxyalkanoate (PHA) biopolymers are widely recognised as outstanding candidates to replace conventional petroleum-derived polymers. Their mechanical properties are good and can be tailored through copolymer composition, they are biodegradable, and unlike many alternatives, they do not rely on oil-based feedstocks. Further, they are the only commodity polymer that can be synthesised intracellularly, ensuring stereoregularity and high molecular weight. However, despite offering enormous potential for many years, they are still not making a significant impact. This is broadly because commercial uptake has been limited by variable performance (inconsistent polymer properties) and high production costs of the raw polymer. Additionally, the main type of PHA produced naturally is poly-3-hydroxybutyrate (PHB), which has limited scope due to its brittle nature and low thermal stability, as well as its tendency to embrittle over time. Production cost is strongly impacted by the type of the feedstock used. In this article we consider: the production of PHAs from methanotrophs using methane as a cost-effective substrate; the use of mixed cultures, as opposed to pure strains; and strategies to generate a poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymer (PHBV), which has more desirable qualities such as toughness and elasticity.
Collapse
Affiliation(s)
- Peter James Strong
- Centre for Solid Waste Bioprocessing, School of Civil Engineering and School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia.
| | - Bronwyn Laycock
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia.
| | | | - Paul Douglas Jensen
- Advanced Water Management Centre, The University of Queensland, Brisbane, Queensland 4072, Australia.
| | - Paul Andrew Lant
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia.
| | - Gene Tyson
- Australian Centre for Ecogenomics, The University of Queensland, Brisbane, Queensland 4072, Australia.
| | - Steven Pratt
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia.
| |
Collapse
|
27
|
Myung J, Galega WM, Van Nostrand JD, Yuan T, Zhou J, Criddle CS. Long-term cultivation of a stable Methylocystis-dominated methanotrophic enrichment enabling tailored production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate). BIORESOURCE TECHNOLOGY 2015; 198:811-818. [PMID: 26454368 DOI: 10.1016/j.biortech.2015.09.094] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 09/21/2015] [Accepted: 09/22/2015] [Indexed: 06/05/2023]
Abstract
Methane (CH4) is a readily available feedstock for production of polyhydroxyalkanoates (PHAs). The structure and PHA production capacity of a Methylocystis-dominated methanotrophic enrichment was stable in long-term operation (>175 days) when grown exponentially under non-aseptic conditions in fill-and-draw batch cultures with ammonium as nitrogen source. Cells harvested in the draw step were incubated in the absence of nitrogen with various combinations of CH4 and valerate to assess capacity for synthesis of poly(3-hydroxybutyrate) (P3HB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). When fed CH4 alone, only P3HB was produced. When fed CH4 plus valerate, PHBV was synthesized. The mol% of 3-hydroxyvalerate (3HV) increased with added valerate. Oxidation of CH4 was required for valerate assimilation, and the fraction of CH4 oxidized increased with increased mol% 3 HV. By separating PHA accumulation from cell replication, tailored PHA-rich biomass can be generated by addition of co-substrate, while retaining a large inoculum for the next cycle of cell division.
Collapse
Affiliation(s)
- Jaewook Myung
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA.
| | - Wakuna M Galega
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA.
| | - Joy D Van Nostrand
- Institute for Environmental Genomics, Department of Microbiology and Plant Science, University of Oklahoma, Norman, OK 73019, USA.
| | - Tong Yuan
- Institute for Environmental Genomics, Department of Microbiology and Plant Science, University of Oklahoma, Norman, OK 73019, USA.
| | - Jizhong Zhou
- Institute for Environmental Genomics, Department of Microbiology and Plant Science, University of Oklahoma, Norman, OK 73019, USA.
| | - Craig S Criddle
- Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA; Woods Institute for the Environment, Stanford, CA 94305, USA; William and Cloy Codiga Resource Recovery Center, Stanford, CA 94305, USA.
| |
Collapse
|
28
|
Chidambarampadmavathy K, Karthikeyan OP, Heimann K. Biopolymers made from methane in bioreactors. Eng Life Sci 2015. [DOI: 10.1002/elsc.201400203] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Affiliation(s)
- Karthigeyan Chidambarampadmavathy
- College of Marine and Environmental Science; James Cook University; Townsville Queensland Australia
- Centre for Sustainable Fisheries and Aquaculture; James Cook University; Townsville Queensland Australia
| | - Obulisamy P. Karthikeyan
- College of Marine and Environmental Science; James Cook University; Townsville Queensland Australia
- Centre for Sustainable Fisheries and Aquaculture; James Cook University; Townsville Queensland Australia
| | - Kirsten Heimann
- College of Marine and Environmental Science; James Cook University; Townsville Queensland Australia
- Centre for Sustainable Fisheries and Aquaculture; James Cook University; Townsville Queensland Australia
- Centre for Biodiscovery and Molecular Development of Therapeutics; James Cook University; Townsville Queensland Australia
- Comparative Genomics Centre; James Cook University; Townsville Queensland Australia
| |
Collapse
|
29
|
Chidambarampadmavathy K, Obulisamy P. K, Heimann K. Role of copper and iron in methane oxidation and bacterial biopolymer accumulation. Eng Life Sci 2015. [DOI: 10.1002/elsc.201400127] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Karthigeyan Chidambarampadmavathy
- Collegeof Marine and Environmental ScienceJames Cook University Townsville Queensland Australia
- Centre for Sustainable Fisheries and AquacultureJames Cook University Townsville Queensland Australia
| | - Karthikeyan Obulisamy P.
- Collegeof Marine and Environmental ScienceJames Cook University Townsville Queensland Australia
- Centre for Sustainable Fisheries and AquacultureJames Cook University Townsville Queensland Australia
| | - Kirsten Heimann
- Collegeof Marine and Environmental ScienceJames Cook University Townsville Queensland Australia
- Centre for Sustainable Fisheries and AquacultureJames Cook University Townsville Queensland Australia
- Centre for Biodiscovery and Molecular Development of TherapeuticsJames Cook University Townsville Queensland Australia
- Comparative Genomics CentreJames Cook University Townsville Queensland Australia
| |
Collapse
|
30
|
López JC, Quijano G, Pérez R, Muñoz R. Assessing the influence of CH4 concentration during culture enrichment on the biodegradation kinetics and population structure. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2014; 146:116-123. [PMID: 25169644 DOI: 10.1016/j.jenvman.2014.06.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 06/25/2014] [Accepted: 06/26/2014] [Indexed: 06/03/2023]
Abstract
Methanotrophic communities were enriched in three stirred tank reactors continuously supplied with CH4-laden air at 20, 2 and 0.2 gCH4 m(-3) in order to evaluate the influence of CH4 concentration on the biodegradation kinetics, population structure and potential polyhydroxyalkanoate production under sequential nitrogen limitations. The population structure of the enriched cultures, dominated by type I methanotrophs, was influenced by CH4 concentration. No significant correlation between CH4 concentration and the maximum specific degradation rate (qmax) or the half-saturation constant (KS) was recorded, microorganisms enriched at 2 gCH4 m(-3) presenting the highest qmax and those enriched at 20 and 0.2 gCH4 m(-3) exhibiting the lowest KS. Maximum polyhydroxybutyrate (PHB) contents of 1.0% and 12.6% (w/w) were achieved at 20 and 2 g CH4 m(-3), respectively. Polyhydroxyvalerate (PHV) was also detected at PHV:PHB ratios of up to 12:1 and 4:1 in the communities enriched at 20 and 0.2 gCH4 m(-3), respectively.
Collapse
Affiliation(s)
- Juan C López
- Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain
| | - Guillermo Quijano
- Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain
| | - Rebeca Pérez
- Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain
| | - Raúl Muñoz
- Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina, s/n, 47011, Valladolid, Spain.
| |
Collapse
|
31
|
Competition between metals for binding to methanobactin enables expression of soluble methane monooxygenase in the presence of copper. Appl Environ Microbiol 2014; 81:1024-31. [PMID: 25416758 DOI: 10.1128/aem.03151-14] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It is well known that copper is a key factor regulating expression of the two forms of methane monooxygenase found in proteobacterial methanotrophs. Of these forms, the cytoplasmic, or soluble, methane monooxygenase (sMMO) is expressed only at low copper concentrations. The membrane-bound, or particulate, methane monooxygenase (pMMO) is constitutively expressed with respect to copper, and such expression increases with increasing copper. Recent findings have shown that copper uptake is mediated by a modified polypeptide, or chalkophore, termed methanobactin. Although methanobactin has high specificity for copper, it can bind other metals, e.g., gold. Here we show that in Methylosinus trichosporium OB3b, sMMO is expressed and active in the presence of copper if gold is also simultaneously present. Such expression appears to be due to gold binding to methanobactin produced by M. trichosporium OB3b, thereby limiting copper uptake. Such expression and activity, however, was significantly reduced if methanobactin preloaded with copper was also added. Further, quantitative reverse transcriptase PCR (RT-qPCR) of transcripts of genes encoding polypeptides of both forms of MMO and SDS-PAGE results indicate that both sMMO and pMMO can be expressed when copper and gold are present, as gold effectively competes with copper for binding to methanobactin. Such findings suggest that under certain geochemical conditions, both forms of MMO may be expressed and active in situ. Finally, these findings also suggest strategies whereby field sites can be manipulated to enhance sMMO expression, i.e., through the addition of a metal that can compete with copper for binding to methanobactin.
Collapse
|
32
|
Kerckhof FM, Courtens ENP, Geirnaert A, Hoefman S, Ho A, Vilchez-Vargas R, Pieper DH, Jauregui R, Vlaeminck SE, Van de Wiele T, Vandamme P, Heylen K, Boon N. Optimized cryopreservation of mixed microbial communities for conserved functionality and diversity. PLoS One 2014; 9:e99517. [PMID: 24937032 PMCID: PMC4061060 DOI: 10.1371/journal.pone.0099517] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 05/15/2014] [Indexed: 12/26/2022] Open
Abstract
The use of mixed microbial communities (microbiomes) for biotechnological applications has steadily increased over the past decades. However, these microbiomes are not readily available from public culture collections, hampering their potential for widespread use. The main reason for this lack of availability is the lack of an effective cryopreservation protocol. Due to this critical need, we evaluated the functionality as well as the community structure of three different types of microbiomes before and after cryopreservation with two cryoprotective agents (CPA). Microbiomes were selected based upon relevance towards applications: (1) a methanotrophic co-culture (MOB), with potential for mitigation of greenhouse gas emissions, environmental pollutants removal and bioplastics production; (2) an oxygen limited autotrophic nitrification/denitrification (OLAND) biofilm, with enhanced economic and ecological benefits for wastewater treatment, and (3) fecal material from a human donor, with potential applications for fecal transplants and pre/probiotics research. After three months of cryopreservation at −80°C, we found that metabolic activity, in terms of the specific activity recovery of MOB, aerobic ammonium oxidizing bacteria (AerAOB) and anaerobic AOB (AnAOB, anammox) in the OLAND mixed culture, resumes sooner when one of our selected CPA [dimethyl sulfoxide (DMSO) and DMSO plus trehalose and tryptic soy broth (DMSO+TT)] was added. However, the activity of the fecal community was not influenced by the CPA addition, although the preservation of the community structure (as determined by 16S rRNA gene sequencing) was enhanced by addition of CPA. In summary, we have evaluated a cryopreservation protocol that succeeded in preserving both community structure and functionality of value-added microbiomes. This will allow individual laboratories and culture collections to boost the use of microbiomes in biotechnological applications.
Collapse
Affiliation(s)
- Frederiek-Maarten Kerckhof
- Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium
| | - Emilie N. P. Courtens
- Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium
| | - Annelies Geirnaert
- Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium
| | - Sven Hoefman
- Laboratory of Microbiology, Faculty of Sciences, Ghent University, Gent, Belgium
| | - Adrian Ho
- Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium
| | - Ramiro Vilchez-Vargas
- Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium
| | - Dietmar H. Pieper
- Microbial Interactions and Processes Research Group, Department of Medical Microbiology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Ruy Jauregui
- Microbial Interactions and Processes Research Group, Department of Medical Microbiology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Siegfried E. Vlaeminck
- Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium
| | - Tom Van de Wiele
- Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium
| | - Peter Vandamme
- Laboratory of Microbiology, Faculty of Sciences, Ghent University, Gent, Belgium
| | - Kim Heylen
- Laboratory of Microbiology, Faculty of Sciences, Ghent University, Gent, Belgium
| | - Nico Boon
- Laboratory of Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium
- * E-mail:
| |
Collapse
|
33
|
Rostkowski KH, Pfluger AR, Criddle CS. Stoichiometry and kinetics of the PHB-producing Type II methanotrophs Methylosinus trichosporium OB3b and Methylocystis parvus OBBP. BIORESOURCE TECHNOLOGY 2013; 132:71-77. [PMID: 23395757 DOI: 10.1016/j.biortech.2012.12.129] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 12/18/2012] [Accepted: 12/19/2012] [Indexed: 06/01/2023]
Abstract
In this study, modeling is used to describe how oxygen and nitrogen source affect the stoichiometry and kinetics of growth and PHB production in the Type II methanotrophs Methylosinus trichosporium OB3b and Methylocystis parvus OBBP. Significant differences were observed, with major implications for the use of these species in biotechnology applications. Such analyses can better inform bioreactor design, scale-up models, and life cycle assessments (LCAs).
Collapse
Affiliation(s)
- Katherine H Rostkowski
- Department of Civil and Environmental Engineering, Stanford University, CA 94305-4020, USA.
| | | | | |
Collapse
|
34
|
Microbial production of poly(hydroxybutyrate) from C₁ carbon sources. Appl Microbiol Biotechnol 2013; 97:1407-24. [PMID: 23306640 DOI: 10.1007/s00253-012-4649-0] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Revised: 12/08/2012] [Accepted: 12/10/2012] [Indexed: 02/01/2023]
Abstract
Polyhydroxybutyrate (PHB) is an attractive substitute for petrochemical plastic due to its similar properties, biocompatibility, and biodegradability. The cost of scaled-up PHB production inhibits its widespread usage. Intensive researches are growing to reduce costs and improve thermomechanical, physical, and processing properties of this green biopolymer. Among cheap substrates which are used for reducing total cost of PHB production, some C₁ carbon sources, e.g., methane, methanol, and CO₂ have received a great deal of attention due to their serious role in greenhouse problem. This article reviews the fundamentals of strategies for reducing PHA production and moves on to the applications of several cheap substrates with a special emphasis on methane, methanol, and CO₂. Also, some explanation for involved microorganisms including the hydrogen-oxidizing bacteria and methanotrophs, their history, culture condition, and nutritional requirements are given. After description of some important strains among the hydrogen-oxidizing and methanotrophic producers of PHB, the article is focused on limitations, threats, and opportunities for application and their future trends.
Collapse
|
35
|
Rostkowski KH, Criddle CS, Lepech MD. Cradle-to-gate life cycle assessment for a cradle-to-cradle cycle: biogas-to-bioplastic (and back). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:9822-9829. [PMID: 22775327 DOI: 10.1021/es204541w] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
At present, most synthetic organic materials are produced from fossil carbon feedstock that is regenerated over time scales of millions of years. Biobased alternatives can be rapidly renewed in cradle-to-cradle cycles (1-10 years). Such materials extend landfill life and decrease undesirable impacts due to material persistence. This work develops a LCA for synthesis of polyhydroxybutyrate (PHB) from methane with subsequent biodegradation of PHB back to biogas (40-70% methane, 30-60% carbon dioxide). The parameters for this cradle-to-cradle cycle for PHB production are developed and used as the basis for a cradle-to-gate LCA. PHB production from biogas methane is shown to be preferable to its production from cultivated feedstock due to the energy and land required for the feedstock cultivation and fermentation. For the PHB-methane cycle, the major challenges are PHB recovery and demands for energy. Some or all of the energy requirements can be satisfied using renewable energy, such as a portion of the collected biogas methane. Oxidation of 18-26% of the methane in a biogas stream can meet the energy demands for aeration and agitation, and recovery of PHB synthesized from the remaining 74-82%. Effective coupling of waste-to-energy technologies could thus conceivably enable PHB production without imported carbon and energy.
Collapse
|