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San Miguel-González GDJ, Alemán-Huerta ME, Martínez-Herrera RE, Quintero-Zapata I, de la Torre-Zavala S, Avilés-Arnaut H, Gandarilla-Pacheco FL, de Luna-Santillana EDJ. Alkaline-Tolerant Bacillus cereus 12GS: A Promising Polyhydroxybutyrate (PHB) Producer Isolated from the North of Mexico. Microorganisms 2024; 12:863. [PMID: 38792693 PMCID: PMC11124092 DOI: 10.3390/microorganisms12050863] [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: 03/21/2024] [Revised: 04/16/2024] [Accepted: 04/24/2024] [Indexed: 05/26/2024] Open
Abstract
Environmental pollution caused by petroleum-derived plastics continues to increase annually. Consequently, current research is interested in the search for eco-friendly bacterial polymers. The importance of Bacillus bacteria as producers of polyhydroxyalkanoates (PHAs) has been recognized because of their physiological and genetic qualities. In this study, twenty strains of Bacillus genus PHA producers were isolated. Production was initially evaluated qualitatively to screen the strains, and subsequently, the strain B12 or Bacillus sp. 12GS, with the highest production, was selected through liquid fermentation. Biochemical and molecular identification revealed it as a novel isolate of Bacillus cereus. Production optimization was carried out using the Taguchi methodology, determining the optimal parameters as 30 °C, pH 8, 150 rpm, and 4% inoculum, resulting in 87% and 1.91 g/L of polyhydroxybutyrate (PHB). Kinetic studies demonstrated a higher production within 48 h. The produced biopolymer was analyzed using Fourier-transform infrared spectroscopy (FTIR), confirming the production of short-chain-length (scl) polyhydroxyalkanoate, named PHB, and differential scanning calorimetry (DSC) analysis revealed thermal properties, making it a promising material for various applications. The novel B. cereus isolate exhibited a high %PHB, emphasizing the importance of bioprospecting, study, and characterization for strains with biotechnological potential.
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Affiliation(s)
- Gustavo de J. San Miguel-González
- Instituto de Biotecnología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, Av. Pedro de Alba y Manuel L. Barragán S/N, San Nicolás de los Garza C.P. 66455, Nuevo León, Mexico; (G.d.J.S.M.-G.); (I.Q.-Z.); (S.d.l.T.-Z.); (H.A.-A.); (F.L.G.-P.)
| | - María E. Alemán-Huerta
- Instituto de Biotecnología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, Av. Pedro de Alba y Manuel L. Barragán S/N, San Nicolás de los Garza C.P. 66455, Nuevo León, Mexico; (G.d.J.S.M.-G.); (I.Q.-Z.); (S.d.l.T.-Z.); (H.A.-A.); (F.L.G.-P.)
| | - Raul E. Martínez-Herrera
- Escuela de Ingenería y Ciencias, Tecnológico de Monterrey, Av. Eugenio Garza Sada 2501 Sur, Tecnológico, Monterrey C.P. 64849, Nuevo León, Mexico
- Institute of Advanced Materials for Sustainable Manufacturing, Tecnológico de Monterrey, Av. Eugenio Garza Sada 2501 Sur, Tecnológico, Monterrey C.P. 64849, Nuevo León, Mexico
| | - Isela Quintero-Zapata
- Instituto de Biotecnología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, Av. Pedro de Alba y Manuel L. Barragán S/N, San Nicolás de los Garza C.P. 66455, Nuevo León, Mexico; (G.d.J.S.M.-G.); (I.Q.-Z.); (S.d.l.T.-Z.); (H.A.-A.); (F.L.G.-P.)
| | - Susana de la Torre-Zavala
- Instituto de Biotecnología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, Av. Pedro de Alba y Manuel L. Barragán S/N, San Nicolás de los Garza C.P. 66455, Nuevo León, Mexico; (G.d.J.S.M.-G.); (I.Q.-Z.); (S.d.l.T.-Z.); (H.A.-A.); (F.L.G.-P.)
| | - Hamlet Avilés-Arnaut
- Instituto de Biotecnología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, Av. Pedro de Alba y Manuel L. Barragán S/N, San Nicolás de los Garza C.P. 66455, Nuevo León, Mexico; (G.d.J.S.M.-G.); (I.Q.-Z.); (S.d.l.T.-Z.); (H.A.-A.); (F.L.G.-P.)
| | - Fátima L. Gandarilla-Pacheco
- Instituto de Biotecnología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, Av. Pedro de Alba y Manuel L. Barragán S/N, San Nicolás de los Garza C.P. 66455, Nuevo León, Mexico; (G.d.J.S.M.-G.); (I.Q.-Z.); (S.d.l.T.-Z.); (H.A.-A.); (F.L.G.-P.)
| | - Erick de J. de Luna-Santillana
- Laboratorio Medicina de Conservación, Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Blvd. del Maestro esq, Elías Piña, Colonia Narciso Mendoza, Reynosa C.P. 88700, Tamaulipas, Mexico;
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Rivas-Castillo AM, Valdez-Calderón A, Angeles-Padilla AF, Figueroa-Ocampo CB, Carrillo-Ibarra S, Quezada-Cruz M, Espinosa-Roa A, Pérez-García BD, Rojas-Avelizapa NG. PHB production by Bacillus megaterium strain MNSH1-9K-1 using low-cost media. Braz J Microbiol 2024; 55:245-254. [PMID: 38212508 PMCID: PMC10920526 DOI: 10.1007/s42770-023-01232-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 12/21/2023] [Indexed: 01/13/2024] Open
Abstract
Plastics are widely used for diverse applications due to their versatility. However, their negative impact on ecosystems is undeniable due to their long-term degradation. Thus, there is a rising need for developing eco-friendlier alternatives to substitute fossil-based plastics, like biopolymers. PHA are synthesized intracellularly by microorganisms under stressful conditions of growth and have similar characteristics to conventional polymers, like their melting point, transition temperatures, crystallinity, and flexibility. Although it is feasible to use biopolymers for diverse industrial applications, their elevated production cost due to the supplies needed for microbiological procedures and the low productivity yields obtained have been the main limiting factors for their commercial success. The present study assessed the ability of Bacillus megaterium strain MNSH1-9K-1 to produce biopolymers using low-cost media from different kinds of fruit-peel residues. The results show that MNSH1-9K-1 can produce up to 58 g/L of PHB when grown in a medium prepared from orange-peel residues. The data obtained provide information to enhance the scalability of these kinds of biotechnological processes.
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Affiliation(s)
- Andrea M Rivas-Castillo
- Universidad Tecnológica de la Zona Metropolitana del Valle de México, Miguel Hidalgo y Costilla 5, Col. Los Héroes de Tizayuca, 43816, Tizayuca, Hgo, México
| | - Alejandro Valdez-Calderón
- Universidad Tecnológica de la Zona Metropolitana del Valle de México, Miguel Hidalgo y Costilla 5, Col. Los Héroes de Tizayuca, 43816, Tizayuca, Hgo, México
| | - Arturo F Angeles-Padilla
- Universidad Tecnológica de la Zona Metropolitana del Valle de México, Miguel Hidalgo y Costilla 5, Col. Los Héroes de Tizayuca, 43816, Tizayuca, Hgo, México
| | - César B Figueroa-Ocampo
- Universidad Tecnológica de la Zona Metropolitana del Valle de México, Miguel Hidalgo y Costilla 5, Col. Los Héroes de Tizayuca, 43816, Tizayuca, Hgo, México
| | - Sandra Carrillo-Ibarra
- Escuela de Ciencias de la Salud, Universidad del Valle de México Campus Zapopan, Periférico Poniente 7900, Col. Jardines de Collí, 45010, Zapopan, Jal, México
| | - Maribel Quezada-Cruz
- Laboratorio de Tecnología Ambiental, Universidad Tecnológica de Tecámac, Carretera Federal México-Pachuca Km 37.5, Predio Sierra Hermosa, 55740, Tecámac, Edo, México
| | - Arian Espinosa-Roa
- CONACyT-Centro de Investigación en Química Aplicada, Unidad Monterrey, Alianza Sur 204, Parque de Innovación e Investigación Tecnológica (PIIT), 66628, Apodaca, N. L, México
| | - Brandon D Pérez-García
- Universidad Tecnológica de la Zona Metropolitana del Valle de México, Miguel Hidalgo y Costilla 5, Col. Los Héroes de Tizayuca, 43816, Tizayuca, Hgo, México
- Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada del IPN, Unidad Querétaro, Cerro Blanco 141, Col. Colinas del Cimatario, 76090, Santiago de Querétaro, Qro, México
| | - Norma G Rojas-Avelizapa
- Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada del IPN, Unidad Querétaro, Cerro Blanco 141, Col. Colinas del Cimatario, 76090, Santiago de Querétaro, Qro, México.
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Kumar R, Sadeghi K, Jang J, Seo J. Mechanical, chemical, and bio-recycling of biodegradable plastics: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 882:163446. [PMID: 37075991 DOI: 10.1016/j.scitotenv.2023.163446] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 04/07/2023] [Accepted: 04/07/2023] [Indexed: 05/03/2023]
Abstract
The extensive use of petroleum-based non-biodegradable plastics for various applications has led to global concerns regarding the severe environmental issues associated with them. However, biodegradable plastics are emerging as green alternatives to petroleum-based non-biodegradable plastics. Biodegradable plastics, which include bio-based and petroleum-based biodegradable polymers, exhibit advantageous properties such as renewability, biocompatibility, and non-toxicity. Furthermore, certain biodegradable plastics are compatible with existing recycling streams intended for conventional plastics and are biodegradable in controlled and/or predicted environments. Recycling biodegradable plastics before their end-of-life (EOL) degradation further enhances their sustainability and reduces their carbon footprint. Since the production of biodegradable plastic is increasing and these materials will coexist with conventional plastics for many years to come, it is essential to identify the optimal recycling options for each of the most prevalent biodegradable plastics. The substitution of virgin biodegradable plastics by their recyclates leads to higher savings in the primary energy demand and reduces global warming impact. This review covers the current state of the mechanical, chemical, and bio-recycling of post-industrial and post-consumer waste of biodegradable plastics and their related composites. The effects of recycling on the chemical structure and thermomechanical properties of biodegradable plastics are also reported. Additionally, the improvement of biodegradable plastics by blending them with other polymers and nanoparticles is comprehensively discussed. Finally, the status of bioplastic usage, life cycle assessment, EOL management, bioplastic market, and the challenges associated with the recyclability of biodegradable plastics are addressed. This review gives comprehensive insights into the recycling processes that may be employed for the recycling of biodegradable plastics.
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Affiliation(s)
- Ritesh Kumar
- Department of Packaging, Yonsei University, 1 Yonseidae-gil, Wonju-si, Gangwon-do 26493, South Korea
| | - Kambiz Sadeghi
- Department of Packaging, Yonsei University, 1 Yonseidae-gil, Wonju-si, Gangwon-do 26493, South Korea
| | - Jaeyoung Jang
- Department of Packaging, Yonsei University, 1 Yonseidae-gil, Wonju-si, Gangwon-do 26493, South Korea
| | - Jongchul Seo
- Department of Packaging, Yonsei University, 1 Yonseidae-gil, Wonju-si, Gangwon-do 26493, South Korea.
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Martínez-Herrera RE, Alemán-Huerta ME, Rutiaga-Quiñones OM, de Luna-Santillana EJ, Elufisan TO. A comprehensive view of Bacillus cereus as a polyhydroxyalkanoate (PHA) producer: A promising alternative to Petroplastics. Process Biochem 2023. [DOI: 10.1016/j.procbio.2023.03.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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Chauviat A, Meyer T, Favre-Bonté S. Versatility of Stenotrophomonas maltophilia: Ecological roles of RND efflux pumps. Heliyon 2023; 9:e14639. [PMID: 37089375 PMCID: PMC10113797 DOI: 10.1016/j.heliyon.2023.e14639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/13/2023] [Accepted: 03/14/2023] [Indexed: 03/30/2023] Open
Abstract
S. maltophilia is a widely distributed bacterium found in natural, anthropized and clinical environments. The genome of this opportunistic pathogen of environmental origin includes a large number of genes encoding RND efflux pumps independently of the clinical or environmental origin of the strains. These pumps have been historically associated with the uptake of antibiotics and clinically relevant molecules because they confer resistance to many antibiotics. However, considering the environmental origin of S. maltophilia, the ecological role of these pumps needs to be clarified. RND efflux systems are highly conserved within bacteria and encountered both in pathogenic and non-pathogenic species. Moreover, their evolutionary origin, conservation and multiple copies in bacterial genomes suggest a primordial role in cellular functions and environmental adaptation. This review is aimed at elucidating the ecological role of S. maltophilia RND efflux pumps in the environmental context and providing an exhaustive description of the environmental niches of S. maltophilia. By looking at the substrates and functions of the pumps, we propose different involvements and roles according to the adaptation of the bacterium to various niches. We highlight that i°) regulatory mechanisms and inducer molecules help to understand the conditions leading to their expression, and ii°) association and functional redundancy of RND pumps and other efflux systems demonstrate their complex role within S. maltophilia cells. These observations emphasize that RND efflux pumps play a role in the versatility of S. maltophilia.
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Devadarshini D, Mohapatra S, Pati S, Maity S, Rath CC, Jena PK, Samantaray D. Evaluation of PHAs production by mixed bacterial culture under submerged fermentation. Biologia (Bratisl) 2022. [DOI: 10.1007/s11756-022-01302-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Liang SY, Wan SC, Ho YP, Horng YT, Soo PC, Peng WP. Rapid Quantification of Polyhydroxybutyrate Polymer from Single Bacterial Cells with Mass Spectrometry. Anal Chem 2022; 94:11734-11738. [PMID: 35977070 DOI: 10.1021/acs.analchem.2c02807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Polyhydroxyalkanoate (PHA) is one of the biocompatible and biodegradable plastics that can be produced and accumulated as granules inside microorganisms. In this study, a new approach to rapidly quantify a short-chain-length PHA, polyhydroxybutyrate (PHB), produced from genetically engineered Escherichia coli containing phaCAB is presented. The mass of each bacterial cell was measured using a laser-induced radio frequency (rf) plasma charge detection quadrupole ion trap mass spectrometer (LIRFP CD QIT-MS), and then, the PHB contents were determined by calculating the change in cellular mass. The quantitative results showed that the PHB contents measured by LIRFP CD QIT-MS were consistent with those by reference analysis, gas chromatography (GC). The PHB content of each bacterial sample can be obtained within 20 min from sampling using LIRFP CD QIT-MS while GC analysis takes 2 days. In addition, LIRFP CD QIT-MS does not use any hazardous chemicals in cellular mass quantification as compared to GC. This indicates that LIRFP CD QIT-MS has potential in routine monitoring of PHB production.
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Affiliation(s)
- Shao-Yu Liang
- Department of Physics, National Dong Hwa University, Shoufeng, Hualien, Taiwan 974
| | - Shih-Chih Wan
- Department of Physics, National Dong Hwa University, Shoufeng, Hualien, Taiwan 974
| | - Yen-Peng Ho
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien, Taiwan 974
| | - Yu-Tze Horng
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien, Hualien, Taiwan 970
| | - Po-Chi Soo
- Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien, Hualien, Taiwan 970
| | - Wen-Ping Peng
- Department of Physics, National Dong Hwa University, Shoufeng, Hualien, Taiwan 974
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Martínez-Avila O, Llenas L, Ponsá S. Sustainable polyhydroxyalkanoates production via solid-state fermentation: Influence of the operational parameters and scaling up of the process. FOOD AND BIOPRODUCTS PROCESSING 2022. [DOI: 10.1016/j.fbp.2021.12.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Optimization of Propagation Medium for Enhanced Polyhydroxyalkanoate Production by Pseudomonas oleovorans. FERMENTATION-BASEL 2021. [DOI: 10.3390/fermentation8010016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Polyhydroxyalkanoates (PHAs) represent a promising alternative to commercially used petroleum-based plastics. Pseudomonas oleovorans is a natural producer of medium-chain-length PHA (mcl-PHA) under cultivation conditions with nitrogen limitation and carbon excess. Two-step cultivation appears to be an efficient but more expensive method of PHA production. Therefore, the aim of this work was to prepare a minimal synthetic medium for maximum biomass yield and to optimize selected independent variables by response surface methodology (RSM). The highest biomass yield (1.71 ± 0.04 g/L) was achieved in the optimized medium containing 8.4 g/L glucose, 5.7 g/L sodium ammonium phosphate and 35.4 mM phosphate buffer. Under these conditions, both carbon and nitrogen sources were completely consumed after 48 h of the cultivation and the biomass yield was 1.7-fold higher than in the conventional medium recommended by the literature. This approach demonstrates the possibility of using two-stage PHA cultivation to obtain the maximum amount of biomass and PHA.
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Chavan S, Yadav B, Tyagi RD, Drogui P. A review on production of polyhydroxyalkanoate (PHA) biopolyesters by thermophilic microbes using waste feedstocks. BIORESOURCE TECHNOLOGY 2021; 341:125900. [PMID: 34523565 DOI: 10.1016/j.biortech.2021.125900] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/31/2021] [Accepted: 09/03/2021] [Indexed: 05/26/2023]
Abstract
Polyhydroxyalkanoates (PHAs) are produced by numerous microbes as a subcellular energy source. Despite of their diverse applications, exorbitant production cost limits their commercial synthesis. Apart from various cost determining factors such as cost-effective feedstocks or economic recovery methods, the use of appropriate bacteria holds the key to reduce the fermentation economics. Extremophiles, especially thermophilic PHA producers, could make the bioprocess economically viable by reducing the production cost in several aspects. Using variety of waste feedstocks as carbon substrates could open the way for the valorisation of industrial waste streams and cost-effective PHA production. Therefore, the article critically reviews the current knowledge of the synthesis of PHA polyesters in thermophilic conditions. Additionally, it summarises several studies on thermophilic PHA producing bacteria grown on various waste substrates. To conclude, the paper focuses on screening and recovery methods as well as technical challenges in thermophilic PHA production.
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Affiliation(s)
- Shraddha Chavan
- INRS Eau, Terre et Environnement, 490, rue de la Couronne, Québec G1K 9A9, Canada
| | - Bhoomika Yadav
- INRS Eau, Terre et Environnement, 490, rue de la Couronne, Québec G1K 9A9, Canada
| | - R D Tyagi
- School of Technology, Huzhou University, China; BOSK-Bioproducts, 100-399 rue Jacquard, Québec (QC) G1N 4J6, Canada.
| | - Patrick Drogui
- INRS Eau, Terre et Environnement, 490, rue de la Couronne, Québec G1K 9A9, Canada
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Li HF, Wang MR, Tian LY, Li ZJ. Production of Polyhydroxyalkanoates (PHAs) by Vibrio alginolyticus Strains Isolated from Salt Fields. Molecules 2021; 26:molecules26206283. [PMID: 34684864 PMCID: PMC8537743 DOI: 10.3390/molecules26206283] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/09/2021] [Accepted: 10/14/2021] [Indexed: 11/16/2022] Open
Abstract
Vibrio alginolyticus is a halophilic organism usually found in marine environments. It has attracted attention as an opportunistic pathogen of aquatic animals and humans, but there are very few reports on polyhydroxyalkanoate (PHA) production using V. alginolyticus as the host. In this study, two V. alginolyticus strains, LHF01 and LHF02, isolated from water samples collected from salt fields were found to produce poly(3-hydroxybutyrate) (PHB) from a variety of sugars and organic acids. Glycerol was the best carbon source and yielded the highest PHB titer in both strains. Further optimization of the NaCl concentration and culture temperature improved the PHB titer from 1.87 to 5.08 g/L in V. alginolyticus LHF01. In addition, the use of propionate as a secondary carbon source resulted in the production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). V. alginolyticus LHF01 may be a promising host for PHA production using cheap waste glycerol from biodiesel refining.
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Vu DH, Wainaina S, Taherzadeh MJ, Åkesson D, Ferreira JA. Production of polyhydroxyalkanoates (PHAs) by Bacillus megaterium using food waste acidogenic fermentation-derived volatile fatty acids. Bioengineered 2021; 12:2480-2498. [PMID: 34115556 PMCID: PMC8806590 DOI: 10.1080/21655979.2021.1935524] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
High production costs still hamper fast expansion of commercial production of polyhydroxyalkanoates (PHAs). This problem is greatly related to the cultivation medium which accounts for up to 50% of the whole process costs. The aim of this research work was to evaluate the potential of using volatile fatty acids (VFAs), derived from acidogenic fermentation of food waste, as inexpensive carbon sources for the production of PHAs through bacterial cultivation. Bacillus megaterium could assimilate glucose, acetic acid, butyric acid, and caproic acid as single carbon sources in synthetic medium with maximum PHAs production yields of 9-11%, on a cell dry weight basis. Single carbon sources were then replaced by a mixture of synthetic VFAs and by a VFAs-rich stream from the acidogenic fermentation of food waste. After 72 h of cultivation, the VFAs were almost fully consumed by the bacterium in both media and PHAs production yields of 9-10%, on cell dry weight basis, were obtained. The usage of VFAs mixture was found to be beneficial for the bacterial growth that tackled the inhibition of propionic acid, iso-butyric acid, and valeric acid when these volatile fatty acids were used as single carbon sources. The extracted PHAs were revealed to be polyhydroxybutyrate (PHB) by characterization methods of Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The obtained results proved the possibility of using VFAs from acidogenic fermentation of food waste as a cheap substrate to reduce the cost of PHAs production.
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Affiliation(s)
- Danh H Vu
- Swedish Centre for Resource Recovery, University of Borås, Sweden
| | - Steven Wainaina
- Swedish Centre for Resource Recovery, University of Borås, Sweden
| | | | - Dan Åkesson
- Swedish Centre for Resource Recovery, University of Borås, Sweden
| | - Jorge A Ferreira
- Swedish Centre for Resource Recovery, University of Borås, Sweden
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