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Amabile C, Abate T, Chianese S, Musmarra D, Muñoz R. Exploring 1,3-Dioxolane Extraction of Poly(3-hydroxybutyrate) and Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from Methylocystis hirsuta and Mixed Methanotrophic Strain: Effect of Biomass-to-Solvent Ratio and Extraction Time. Polymers (Basel) 2024; 16:1910. [PMID: 39000765 PMCID: PMC11244194 DOI: 10.3390/polym16131910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 06/17/2024] [Accepted: 07/01/2024] [Indexed: 07/17/2024] Open
Abstract
The increasing need for biodegradable polymers demands efficient and environmentally friendly extraction methods. In this study, a simple and sustainable method for extracting polyhydroxybutyrate (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate (PHB-co-HV) from Methylocystis hirsuta and a mixed methanotrophic consortium with different biopolymer contents was presented. The extraction of biopolymers with 1,3-dioxolane was initially investigated by varying the biomass-to-solvent ratio (i.e., 1:2 w v-1, 1:4 w v-1, 1:6 w v-1, 1:8 w v-1 and 1:10 w v-1) and extraction time (6, 8 and 10 h) at the boiling point of the solvent and atmospheric pressure. Based on the results of the preliminary tests, and only for the most efficient biomass-to-solvent ratio, the extraction kinetics were also studied over a time interval ranging from 30 min to 6 h. For Methylocystis hirsuta, the investigation of the extraction time showed that the maximum extraction was reached after 30 min, with recovery yields of 87% and 75% and purities of 98.7% and 94% for PHB and PHB-co-HV, respectively. Similarly, the extraction of PHB and PHB-co-HV from a mixed methanotrophic strain yielded 88% w w-1 and 70% w w-1 recovery, respectively, with 98% w w-1 purity, at a biomass-to-solvent ratio of 6 in 30 min.
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Affiliation(s)
- Claudia Amabile
- Department of Engineering, University of Campania “Luigi Vanvitelli”, Via Roma 29, 81031 Aversa, Italy; (C.A.); (T.A.); (S.C.); (D.M.)
- 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; (C.A.); (T.A.); (S.C.); (D.M.)
- 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; (C.A.); (T.A.); (S.C.); (D.M.)
| | - Dino Musmarra
- Department of Engineering, University of Campania “Luigi Vanvitelli”, Via Roma 29, 81031 Aversa, Italy; (C.A.); (T.A.); (S.C.); (D.M.)
| | - Raul Muñoz
- Institute of Sustainable Processes, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain
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2
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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.
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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
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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.
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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.
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Abate T, Amabile C, Muñoz R, Chianese S, Musmarra D. Polyhydroxyalkanoate recovery overview: properties, characterizations, and extraction strategies. CHEMOSPHERE 2024; 356:141950. [PMID: 38599326 DOI: 10.1016/j.chemosphere.2024.141950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 02/27/2024] [Accepted: 04/07/2024] [Indexed: 04/12/2024]
Abstract
Due to their excellent properties, polyhydroxyalkanoates are gaining increasing recognition in the biodegradable polymer market. These biogenic polyesters are characterized by high biodegradability in multiple environments, overcoming the limitation of composting plants only and their versatility in production. The most consolidated techniques in the literature or the reference legislation for the physical, chemical and mechanical characterisation of the final product are reported since its usability on the market is still linked to its quality, including the biodegradability certificate. This versatility makes polyhydroxyalkanoates a promising prospect with the potential to replace fossil-based thermoplastics sustainably. This review analyses and compares the physical, chemical and mechanical properties of poly-β-hydroxybutyrate and poly-β-hydroxybutyrate-co-β-hydroxyvalerate, indicating their current limitations and strengths. In particular, the copolymer is characterised by better performance in terms of crystallinity, hardness and workability. However, the knowledge in this area is still in its infancy, and the selling prices are too high (9-18 $ kg-1). An analysis of the main extraction techniques, established and in development, is also included. Solvent extraction is currently the most widely used method due to its efficiency and final product quality. In this context, the extraction phase of the biopolymer production process remains a major challenge due to its high costs and the need to use non-halogenated toxic solvents to improve the production of good-quality bioplastics. The review also discusses all fundamental parameters for optimising the process, such as solubility and temperature.
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Affiliation(s)
- 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
| | - 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
| | - 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
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5
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Pérez V, Lebrero R, Muñoz R, Pérez R. The fundamental role of pH in CH4 bioconversion into polyhydroxybutyrate in mixed methanotrophic cultures. CHEMOSPHERE 2024; 355:141832. [PMID: 38570044 DOI: 10.1016/j.chemosphere.2024.141832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 03/13/2024] [Accepted: 03/26/2024] [Indexed: 04/05/2024]
Abstract
Climate change and plastic pollution are likely the most relevant challenges for the environment in the 21st century. Developing cost-effective technologies for the bioconversion of methane (CH4) into polyhydroxyalkanoates (PHAs) could simultaneously mitigate CH4 emissions and boost the commercialization of biodegradable polymers. Despite the fact that the role of temperature, nitrogen deprivation, CH4:O2 ratio or micronutrients availability on the PHA accumulation capacity of methanotrophs has been carefully explored, there is still a need for optimization of the CH4-to-PHA bioconversion process prior to becoming a feasible platform in future biorefineries. In this study, the influence of different cultivation broth pH values (5.5, 7, 8.5 and 10) on bacterial biomass growth, CH4 bioconversion rate, PHA accumulation capacity and bacterial community structure was investigated in a stirred tank bioreactor under nitrogen deprivation conditions. Higher CH4 elimination rates were obtained at increasing pH, with a maximum value of 50.4 ± 2.7 g CH4·m-3·h-1 observed at pH 8.5. This was likely mediated by an increased ionic strength in the mineral medium, which enhanced the gas-liquid mass transfer. Interestingly, higher PHB accumulations were observed at decreasing pH, with the highest PHB contents recorded at a pH 5.5 (43.7 ± 3.4 %w·w-1). The strong selective pressure of low pH towards the growth of Type II methanotrophic bacteria could explain this finding. The genus Methylocystis increased its abundance from 34 % up to 85 and 90 % at pH 5.5 and 7, respectively. On the contrary, Methylocystis was less abundant in the community enriched at pH 8.5 (14 %). The accumulation of intracellular PHB as energy and carbon storage material allowed the maintenance of high CH4 biodegradation rates during 48 h after complete nitrogen deprivation. The results here obtained demonstrated for the first time a crucial and multifactorial role of pH on the bioconversion performance of CH4 into PHA.
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Affiliation(s)
- V Pérez
- Institute of Sustainable Processes, Valladolid University, Dr. Mergelina s/n, Spain; Department of Chemical Engineering and Environmental Technology, Valladolid University, Prado de la Magdalena 5, Valladolid, Spain
| | - R Lebrero
- Institute of Sustainable Processes, Valladolid University, Dr. Mergelina s/n, Spain; Department of Chemical Engineering and Environmental Technology, Valladolid University, Prado de la Magdalena 5, Valladolid, Spain
| | - R Muñoz
- Institute of Sustainable Processes, Valladolid University, Dr. Mergelina s/n, Spain; Department of Chemical Engineering and Environmental Technology, Valladolid University, Prado de la Magdalena 5, Valladolid, Spain
| | - R Pérez
- Institute of Sustainable Processes, Valladolid University, Dr. Mergelina s/n, Spain; Department of Chemical Engineering and Environmental Technology, Valladolid University, Prado de la Magdalena 5, Valladolid, Spain.
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6
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Gęsicka A, Gutowska N, Palaniappan S, Oleskowicz-Popiel P, Łężyk M. Enrichment of mixed methanotrophic cultures producing polyhydroxyalkanoates (PHAs) from various environmental sources. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168844. [PMID: 38029989 DOI: 10.1016/j.scitotenv.2023.168844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/31/2023] [Accepted: 11/22/2023] [Indexed: 12/01/2023]
Abstract
Methanotrophic bacteria can use atmospheric methane (CH4) as a sole carbon source for the growth and production of polyhydroxyalkanoates (PHA). The development of CH4 bioconversion processes relies heavily on the selection of an efficient methanotrophic culture. This research assessed the effect of selected growth conditions, such as nitrogen sources on the enrichment of methanotrophic cultures from various environments for PHA accumulation. Nitrate-based medium favoured the culture growth and selection for PHA-producing methanotrophic cultures with Methylocystis sp. as a major genus and accumulation of up to 27 % polyhydroxybutyrate (PHB) in the biomass. Three PHB-producing cultures: enriched from waste activated sludge (AS), peat bog soil (PB) and landfill biocover soil (LB) were then tested for their ability to produce PHA copolymer at different CH4:O2 ratios. All enriched cultures were able to utilise valeric acid as a cosubstrate for the accumulation of PHA with a 3-hydroxyvaleric (3HV) fraction of 21-41 mol% depending on the inoculum source and CH4 concentration. The process performance of selected cultures was evaluated and compared to the culture of reference strain Methylocystis hirsuta DSM 18500. All mixed cultures irrespective of their inoculum source had similar levels of 3HV fraction in the PHA (38 ± 2 mol%). The highest poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) production was observed for AS culture at 10 % CH4 with an accumulation of 27 ± 3 % of dry cell weight (DCW), 3HV fraction of 39 ± 2 mol% and yield of 0.42 ± 0.02 g-PHA/g-substrate.
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Affiliation(s)
- Aleksandra Gęsicka
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Natalia Gutowska
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Sivasankar Palaniappan
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Piotr Oleskowicz-Popiel
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Mateusz Łężyk
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland.
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Ma R, Li J, Tyagi RD, Zhang X. Carbon dioxide and methane as carbon source for the production of polyhydroxyalkanoates and concomitant carbon fixation. BIORESOURCE TECHNOLOGY 2024; 391:129977. [PMID: 37925086 DOI: 10.1016/j.biortech.2023.129977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/01/2023] [Accepted: 11/01/2023] [Indexed: 11/06/2023]
Abstract
The currently used plastics are non-biodegradable, and cause greenhouse gases (GHGs) emission as they are petroleum-based. Polyhydroxyalkanoates (PHAs) are biopolymers with excellent biodegradability and biocompatibility, which can be used to replace petroleum-based plastics. A variety of microorganisms have been found to synthesize PHAs by using typical GHGs: carbon dioxide and methane as carbon sources. Converting carbon dioxide (CO2) and methane (CH4) to PHAs is an attractive option for carbon capture and biodegradable plastic production. In this review, the microorganisms capable of using CO2 and CH4 to produce PHAs were summarized. The metabolic mechanism, PHAs production process, and the factors influencing the production process are illustrated. The currently used optimization techniques to improve the yield of PHAs are discussed. The challenges and future prospects for developing economically viable PHAs production using GHGs as carbon source are identified. This work provides an insight for achieving carbon sequestration and bioplastics based circular economy.
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Affiliation(s)
- Rui Ma
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, Shenzhen Guangdong 518055, PR China
| | - Ji Li
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, Shenzhen Guangdong 518055, PR China
| | - R D Tyagi
- Chief Scientific Officer, BOSK-Bioproducts, Quebec, Canada
| | - Xiaolei Zhang
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology, Shenzhen, Shenzhen Guangdong 518055, PR China.
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8
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Rodríguez Y, García S, Lebrero R, Muñoz R. Continuous polyhydroxybutyrate production from biogas in an innovative two-stage bioreactor configuration. Biotechnol Bioeng 2023; 120:3224-3233. [PMID: 37497590 DOI: 10.1002/bit.28507] [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: 01/20/2023] [Revised: 04/20/2023] [Accepted: 07/11/2023] [Indexed: 07/28/2023]
Abstract
Biogas biorefineries have opened up new horizons beyond heat and electricity production in the anaerobic digestion sector. Added-value products such as polyhydroxyalkanoates (PHAs), which are environmentally benign and potential candidates to replace conventional plastics, can be generated from biogas. This work investigated the potential of an innovative two-stage growth-accumulation system for the continuous production of biogas-based polyhydroxybutyrate (PHB) using Methylocystis hirsuta CSC1 as cell factory. The system comprised two turbulent bioreactors in series to enhance methane and oxygen mass transfer: a continuous stirred tank reactor (CSTR) and a bubble column bioreactor (BCB) with internal gas recirculation. The CSTR was devoted to methanotrophic growth under nitrogen balanced growth conditions and the BCB targeted PHB production under nitrogen limiting conditions. Two different operational approaches under different nitrogen loading rates and dilution rates were investigated. A balanced nitrogen loading rate along with a dilution rate (D) of 0.3 day-1 resulted in the most stable operating conditions and a PHB productivity of ~53 g PHB m-3 day-1 . However, higher PHB productivities (~127 g PHB m-3 day-1 ) were achieved using nitrogen excess at a D = 0.2 day-1 . Overall, the high PHB contents (up to 48% w/w) obtained in the CSTR under theoretically nutrient balanced conditions and the poor process stability challenged the hypothetical advantages conferred by multistage vs single-stage process configurations for long-term PHB production.
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Affiliation(s)
- Yadira Rodríguez
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Valladolid, Spain
- Institute of Sustainable Processes, Valladolid, Spain
| | - Silvia García
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Valladolid, Spain
- Institute of Sustainable Processes, Valladolid, Spain
| | - Raquel Lebrero
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Valladolid, Spain
- Institute of Sustainable Processes, Valladolid, Spain
| | - Raúl Muñoz
- Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Valladolid, Spain
- Institute of Sustainable Processes, Valladolid, Spain
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9
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Weng C, Peng X, Han Y. From methane to value-added bioproducts: microbial metabolism, enzymes, and metabolic engineering. ADVANCES IN APPLIED MICROBIOLOGY 2023; 124:119-146. [PMID: 37597946 DOI: 10.1016/bs.aambs.2023.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/21/2023]
Abstract
Methane is abundant in nature, and excessive emissions will cause the greenhouse effect. Methane is also an ideal carbon and energy feedstock for biosynthesis. In the review, the microorganisms, metabolism, and enzymes for methane utilization, and the advances of conversion to value-added bioproducts were summarized. First, the physiological characteristics, classification, and methane oxidation process of methanotrophs were introduced. The metabolic pathways for methane utilization and key intermediate metabolites of native and synthetic methanotrophs were summarized. Second, the enzymatic properties, crystal structures, and catalytic mechanisms of methane-oxidizing and metabolizing enzymes in methanotrophs were described. Third, challenges and prospects in metabolic pathways and enzymatic catalysis for methane utilization and conversion to value-added bioproducts were discussed. Finally, metabolic engineering of microorganisms for methane biooxidation and bioproducts synthesis based on different pathways were summarized. Understanding the metabolism and challenges of microbial methane utilization will provide insights into possible strategies for efficient methane-based synthesis.
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Affiliation(s)
- Caihong Weng
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, P.R. China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing, P.R. China
| | - Xiaowei Peng
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, P.R. China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing, P.R. China
| | - Yejun Han
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, P.R. China; School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing, P.R. China.
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10
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Amabile C, Abate T, De Crescenzo C, Sabbarese S, Muñoz R, Chianese S, Musmarra D. Sustainable Process for the Production of Poly(3-hydroxybutyrate- co-3-hydroxyvalerate) from Renewable Resources: A Simulation Study. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2022; 10:14230-14239. [PMID: 36340972 PMCID: PMC9632471 DOI: 10.1021/acssuschemeng.2c04111] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Bacterially produced polyhydroxyalkanoates are valuable substitutes for petrochemical plastics, but their current production capacities are very scarce. Producing poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-co-HV) from methane and odd-chain carbon fatty acids could make the production of this biodegradable polymer cost-effective. This study analyzes the main factors affecting methanotrophic growth and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) accumulation, simulating a pilot-scale process based on a double-stage approach. The effects of the nitrogen source and the oxygen partial pressure during a 20 day growth phase were studied; the cosubstrate concentration, the culture selected, and the methane partial pressure were investigated during the poly(3-hydroxybutyrate-co-3-hydroxyvalerate) production stage performed within 15 days under nutrient starvation. Methylocystis parvus OBBP and Methylosinus thricosporum OB3b reached the maximum growth productivities with ammonium as the nitrogen source and oxygen at high partial pressure. The simulation of the PHB-co-HV accumulation revealed that methanotrophs could better accumulate the polymer with low valeric acid concentrations. A methane-abundant gas stream (0.5 atm of methane) could increase process yields up to 0.32 kg m-3 d-1.
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Affiliation(s)
- Claudia Amabile
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, 81031Aversa, Italy
| | - Teresa Abate
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, 81031Aversa, Italy
| | - Carmen De Crescenzo
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, 81031Aversa, Italy
| | - Simona Sabbarese
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, 81031Aversa, Italy
| | - Raul Muñoz
- Institute
of Sustainable Processes, University of
Valladolid, Dr. Mergelina, s/n, 47011Valladolid, Spain
| | - Simeone Chianese
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, 81031Aversa, Italy
| | - Dino Musmarra
- Department
of Engineering, University of Campania “Luigi
Vanvitelli”, Via Roma 29, 81031Aversa, Italy
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11
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Cattaneo CR, Rodríguez Y, Rene ER, García-Depraect O, Muñoz R. Biogas bioconversion into poly(3-hydroxybutyrate) by a mixed microbial culture in a novel Taylor flow bioreactor. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 150:364-372. [PMID: 35914413 DOI: 10.1016/j.wasman.2022.07.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 07/07/2022] [Accepted: 07/16/2022] [Indexed: 06/15/2023]
Abstract
Biogas-based biopolymer production represents an alternative biogas valorization route with potential to cut down plastic pollution and greenhouse gas emissions. This study investigated for the first time the continuous bioconversion of methane, contained in biogas, into poly(3-hydroxybutyrate) (PHB) by a mixed methanotrophic culture using an innovative high mass-transfer Taylor flow bioreactor. Following a hydrodynamic flow regime mapping, the influence of the gas residence time and the internal gas recirculation on CH4 abatement was assessed under non nutrient limiting conditions. Under optimal operational conditions (gas residence time of 60 min and internal gas recycling ratio of 17), the bioreactor was able to support a CH4 removal efficiency of 63.3%, a robust CH4 elimination capacity (17.2 g-CH4 m-3h-1) and a stable biomass concentration (1.0 g L-1). The simultaneous CH4 abatement and PHB synthesis was investigated under 24-h:24-h nitrogen feast/famine continuous operation. The cyclic nitrogen starvation and the Taylor flow imposed in the bioreactor resulted in a relatively constant biomass concentration of 0.6 g L-1 with PHB contents ranging from 11 to 32% w w-1 (on a dry weight basis), entailing an average PHB productivity of 5.9 g-PHB m-3 d-1 with an associated PHB yield of 19.8 mg-PHB g-CH4-1. Finally, the molecular analysis of the microbial population structure indicated that type II methanotrophs outcompeted non-PHB accumulating type I methanotrophs, with a heterotrophic-methanotrophic consortium enriched in Methylocystis, Hyphomicrobium, Rubinisphaeraceae SH PL14 and Pseudonocardia.
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Affiliation(s)
- Carlos R Cattaneo
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain; Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain; Department of Water Supply, Sanitation and Environmental Engineering, IHE Delft Institute for Water Education, Westvest 7, 2611AX Delft, the Netherlands
| | - Yadira Rodríguez
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain; Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Eldon R Rene
- Department of Water Supply, Sanitation and Environmental Engineering, IHE Delft Institute for Water Education, Westvest 7, 2611AX Delft, the Netherlands
| | - Octavio García-Depraect
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain; Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Raúl Muñoz
- Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain; Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina s/n, 47011 Valladolid, Spain.
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12
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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%.
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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.
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13
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Yáñez L, Rodríguez Y, Scott F, Vergara-Fernández A, Muñoz R. Production of (R)-3-hydroxybutyric acid from methane by in vivo depolymerization of polyhydroxybutyrate in Methylocystis parvus OBBP. BIORESOURCE TECHNOLOGY 2022; 353:127141. [PMID: 35405209 DOI: 10.1016/j.biortech.2022.127141] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 04/06/2022] [Accepted: 04/07/2022] [Indexed: 06/14/2023]
Abstract
Methylocystis parvus OBBP accumulates polyhydroxybutyrate (PHB) using methane as the sole carbon and energy source. In this work, the feasibility of producing (R)-3-hydroxybutyric acid (R3HBA) via intracellularly accumulated PHB through depolymerization (in-vivo) was investigated. Results showed that a PHB to R3HBA conversion of 77.2 ± 0.9% (R3HBA titer of 0.153 ± 0.002 g L-1) can be attained in a mineral medium containing 1 g L-1 KNO3 at 30 °C with shaking at 200 rpm and a constant pH of 11 for 72 h. Nitrogen deprivation and neutral or acidic pHs strongly reduced the excreted R3HBA concentration. Reduced oxygen availability negatively affected the R3HBA yield, which decreased to 73.6 ± 4.9% (titer of 0.139 ± 0.01 g L-1) under microaerobic conditions. Likewise, the presence of increasing concentrations of R3HBA in the medium before the onset of PHB depolymerization reduced the initial R3HBA release rate and R3HBA yield.
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Affiliation(s)
- Luz Yáñez
- Institute of Sustainable Processes, Universidad de Valladolid, Doctor Mergelina s/n, 47011, Spain; Green Technology Research Group, Facultad de Ingeniería y Ciencias Aplicadas, Universidad de Los Andes, 7550000, Chile.
| | - Yadira Rodríguez
- Institute of Sustainable Processes, Universidad de Valladolid, Doctor Mergelina s/n, 47011, Spain.
| | - Felipe Scott
- Green Technology Research Group, Facultad de Ingeniería y Ciencias Aplicadas, Universidad de Los Andes, 7550000, Chile.
| | - Alberto Vergara-Fernández
- Green Technology Research Group, Facultad de Ingeniería y Ciencias Aplicadas, Universidad de Los Andes, 7550000, Chile.
| | - Raúl Muñoz
- Institute of Sustainable Processes, Universidad de Valladolid, Doctor Mergelina s/n, 47011, Spain.
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14
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Govindaraju A, Good NM, Zytnick AM, Martinez-Gomez NC. Employing methylotrophs for a green economy: one-carbon to fuel them all and through metabolism redesign them. Curr Opin Microbiol 2022; 67:102145. [PMID: 35525169 DOI: 10.1016/j.mib.2022.102145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 02/24/2022] [Accepted: 02/28/2022] [Indexed: 11/03/2022]
Abstract
Microbial platforms are currently being optimized to revolutionize industrial energy production while mitigating shortages of global resources and food supplies. Here, we address recent advances to develop bacterial methylotrophic platforms as promising platforms enabling the reuse of products and materials (at their highest value) while reducing waste and pollution.
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Affiliation(s)
- Alekhya Govindaraju
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Nathan M Good
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
| | - Alexa M Zytnick
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA
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Yoon J, Oh MK. Strategies for Biosynthesis of C1 Gas-derived Polyhydroxyalkanoates: A review. BIORESOURCE TECHNOLOGY 2022; 344:126307. [PMID: 34767907 DOI: 10.1016/j.biortech.2021.126307] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 06/13/2023]
Abstract
Biosynthesis of polyhydroxyalkanoates (PHAs) from C1 gases is highly desirable in solving problems such as climate change and microplastic pollution. PHAs are biopolymers synthesized in microbial cells and can be used as alternatives to petroleum-based plastics because of their biodegradability. Because 50% of the cost of PHA production is due to organic carbon sources and salts, the utilization of costless C1 gases as carbon sources is expected to be a promising approach for PHA production. In this review, strategies for PHA production using C1 gases through fermentation and metabolic engineering are discussed. In particular, autotrophs, acetogens, and methanotrophs are strains that can produce PHA from CO2, CO, and CH4. In addition, integrated bioprocesses for the efficient utilization of C1 gases are introduced. Biorefinery processes from C1 gas into bioplastics are prospective strategies with promising potential and feasibility to alleviate environmental issues.
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Affiliation(s)
- Jihee Yoon
- Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul 02841, Republic of Korea
| | - Min-Kyu Oh
- Department of Chemical and Biological Engineering, Korea University, Seongbuk-gu, Seoul 02841, Republic of Korea.
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16
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Gęsicka A, Oleskowicz-Popiel P, Łężyk M. Recent trends in methane to bioproduct conversion by methanotrophs. Biotechnol Adv 2021; 53:107861. [PMID: 34710553 DOI: 10.1016/j.biotechadv.2021.107861] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 10/11/2021] [Accepted: 10/20/2021] [Indexed: 12/26/2022]
Abstract
Methane is an abundant and low-cost gas with high global warming potential and its use as a feedstock can help mitigate climate change. Variety of valuable products can be produced from methane by methanotrophs in gas fermentation processes. By using methane as a sole carbon source, methanotrophic bacteria can produce bioplastics, biofuels, feed additives, ectoine and variety of other high-value chemical compounds. A lot of studies have been conducted through the years for natural methanotrophs and engineered strains as well as methanotrophic consortia. These have focused on increasing yields of native products as well as proof of concept for the synthesis of new range of chemicals by metabolic engineering. This review shows trends in the research on key methanotrophic bioproducts since 2015. Despite certain limitations of the known production strategies that makes commercialization of methane-based products challenging, there is currently much attention placed on the promising further development.
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Affiliation(s)
- Aleksandra Gęsicka
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland
| | - Piotr Oleskowicz-Popiel
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland.
| | - Mateusz Łężyk
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland.
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17
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Ángeles R, Arnaiz E, Gutiérrez J, Muñoz R, Lebrero R. Biogas-based production of glycogen by Nostoc muscorum: Assessing the potential of transforming CO 2 into value added products. CHEMOSPHERE 2021; 275:129885. [PMID: 33636520 DOI: 10.1016/j.chemosphere.2021.129885] [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: 08/30/2020] [Revised: 01/08/2021] [Accepted: 02/02/2021] [Indexed: 06/12/2023]
Abstract
The potential of the filamentous N2-fixing cyanobacterium Nostoc muscorum for CO2 capture from high-loaded streams (i.e. flue gas or biogas) combined with the accumulation of glycogen (GL) and polyhydroxybutyrate (PHB), was evaluated under nutrient-sufficient and nutrient-limited conditions. N. muscorum was able to grow under CO2 contents from 0.03 up to 30% v/v, thus tolerating CO2 concentrations similar to those found in raw biogas or flue-gas, with maximum CO2-fixation rates of 191.9 ± 46 g m-3 d-1 at a biomass concentration of 733.3 ± 207.4 mg TSS L-1. Despite N. muscorum was inhibited by the presence of H2S, the co-inoculation with activated sludge resulted in both CO2 and H2S depletion. Moreover, N. muscorum accumulated GL up to ∼54% dcw under N and P-deprivation, almost 36 times higher than that recorded under nutrients sufficient condition. The addition of 10% extra carbon in the form of valeric acid not only did not hamper the growth of N. muscorum (336.0 ± 113.1 mg TSS L-1) but also increased the GL content to ∼58% dcw. On the contrary, a negligible PHB accumulation was found under the tested conditions, likely due to the high CO2 concentration of 30% v/v in the headspace and therefore the high availability of inorganic carbon for the cultures. N. muscorum cultures achieved VFAs degradations up to ∼78% under controlled pH. These results supported N. muscorum as a sustainable alternative for CO2-capture and greenhouse gas mitigation or for photosynthetic biogas upgrading coupled with value added biomass production.
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Affiliation(s)
- Roxana Ángeles
- Department of Chemical Engineering and Environmental Technology, University of Valladolid. Dr. Mergelina S/n., 47011, Valladolid, Spain; Institute of Sustainable Processes, University of Valladolid. Spain, Dr. Mergelina S/n., 47011, Valladolid, Spain
| | - Esther Arnaiz
- Department of Chemical Engineering and Environmental Technology, University of Valladolid. Dr. Mergelina S/n., 47011, Valladolid, Spain; Institute of Sustainable Processes, University of Valladolid. Spain, Dr. Mergelina S/n., 47011, Valladolid, Spain
| | - Julia Gutiérrez
- 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; Institute of Sustainable Processes, University of Valladolid. Spain, Dr. Mergelina S/n., 47011, Valladolid, Spain
| | - Raquel Lebrero
- Department of Chemical Engineering and Environmental Technology, University of Valladolid. Dr. Mergelina S/n., 47011, Valladolid, Spain; Institute of Sustainable Processes, University of Valladolid. Spain, Dr. Mergelina S/n., 47011, Valladolid, Spain.
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18
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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.
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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.
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