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Rodrigues T, Torres CAV, Marques S, Gírio F, Freitas F, Reis MAM. Polyhydroxyalkanoate Production from Eucalyptus Bark's Enzymatic Hydrolysate. Materials (Basel) 2024; 17:1773. [PMID: 38673131 PMCID: PMC11050922 DOI: 10.3390/ma17081773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/06/2024] [Accepted: 04/09/2024] [Indexed: 04/28/2024]
Abstract
In recent years, polyhydroxyalkanoates (PHAs) have gained notoriety because of their desirable properties that include proven biodegradability, biocompatibility, and thermal stability, which make them suitable alternatives to fossil-based polymers. However, the widespread use of PHAs is still challenging because of their production costs, which are greatly associated with the cultivation medium used for bacterial cultivation. In Portugal, one-quarter of the forest area is covered by Eucalyptus globulus wood, making its residues a cheap, abundant, and sustainable potential carbon source for biotechnological uses. In this work, eucalyptus bark was used as the sole feedstock for PHA production in a circular bioeconomic approach. Eucalyptus bark hydrolysate was obtained after enzymatic saccharification using Cellic® CTec3, resulting in a sugar-rich solution containing glucose and xylose. Although with differing performances, several bacteria were able to grow and produce PHA with distinct compositions, using the enzymatic hydrolysate as the sole carbon source. Pseudomonas citronellolis NRRL B-2504 achieved a high cellular growth rate in bioreactor assays (24.4 ± 0.15 g/L) but presented a low accumulation of a medium-chain-length PHA (mcl-PHA) comprising the monomers hydroxydecanoate (HD, 65%), hydroxydodecanoate (HDd, 25%), and hydroxytetradecanoate (HTd, 14%). Burkholderia thailandensis E264, on the other hand, reached a lower cellular growth rate (8.87 ± 0.34 g/L) but showed a higher biopolymer accumulation, with a polyhydroxybutyrate (PHB) content in the cells of 12.3 wt.%. The new isolate, Pseudomonas sp., revealed that under nitrogen availability, it was able to reach a higher accumulation of the homopolymer PHB (31 wt.%). These results, although preliminary, demonstrate the suitability of eucalyptus bark's enzymatic hydrolysate as a feedstock for PHA production, thus offering an exciting avenue for achieving sustainable and environmentally responsible plastic products from an undervalued forestry waste.
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Affiliation(s)
- Thomas Rodrigues
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; (T.R.); (C.A.V.T.); (M.A.M.R.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - Cristiana A. V. Torres
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; (T.R.); (C.A.V.T.); (M.A.M.R.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - Susana Marques
- Unidade de Bioenergia e Biorrefinarias, Laboratório Nacional de Energia e Geologia I.P., 2610-999 Lisboa, Portugal; (S.M.); (F.G.)
| | - Francisco Gírio
- Unidade de Bioenergia e Biorrefinarias, Laboratório Nacional de Energia e Geologia I.P., 2610-999 Lisboa, Portugal; (S.M.); (F.G.)
| | - Filomena Freitas
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; (T.R.); (C.A.V.T.); (M.A.M.R.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - Maria A. M. Reis
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; (T.R.); (C.A.V.T.); (M.A.M.R.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
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Catalão M, Fernandes M, Galdon L, Rodrigues CF, Sobral RG, Gaudêncio SP, Torres CAV. Exopolysaccharide Production from Marine-Derived Brevundimonas huaxiensis Obtained from Estremadura Spur Pockmarks Sediments Revealing Potential for Circular Economy. Mar Drugs 2023; 21:419. [PMID: 37504950 PMCID: PMC10381572 DOI: 10.3390/md21070419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/20/2023] [Accepted: 07/20/2023] [Indexed: 07/29/2023] Open
Abstract
Marine environments represent an enormous biodiversity reservoir due to their numerous different habitats, being abundant in microorganisms capable of producing biomolecules, namely exopolysaccharides (EPS), with unique physical characteristics and applications in a broad range of industrial sectors. From a total of 67 marine-derived bacteria obtained from marine sediments collected at depths of 200 to 350 m from the Estremadura Spur pockmarks field, off the coast of Continental Portugal, the Brevundimonas huaxiensis strain SPUR-41 was selected to be cultivated in a bioreactor with saline culture media and glucose as a carbon source. The bacterium exhibited the capacity to produce 1.83 g/L of EPS under saline conditions. SPUR-41 EPS was a heteropolysaccharide composed of mannose (62.55% mol), glucose (9.19% mol), rhamnose (19.41% mol), glucuronic acid (4.43% mol), galactose (2.53% mol), and galacturonic acid (1.89% mol). Moreover, SPUR-41 EPS also revealed acyl groups in its composition, namely acetyl, succinyl, and pyruvyl. This study revealed the importance of research on marine environments for the discovery of bacteria that produce new value-added biopolymers for pharmaceutical and other biotechnological applications, enabling us to potentially address saline effluent pollution via a sustainable circular economy.
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Affiliation(s)
- Marta Catalão
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
- UCIBIO-Applied Molecular Biosciences Unit, Chemistry and Life Sciences Departments, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
| | - Mafalda Fernandes
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
- UCIBIO-Applied Molecular Biosciences Unit, Chemistry and Life Sciences Departments, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
| | - Lorena Galdon
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
- UCIBIO-Applied Molecular Biosciences Unit, Chemistry and Life Sciences Departments, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
| | - Clara F Rodrigues
- CESAM-Centre for Environmental and Marine Studies, Department of Biology, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Rita G Sobral
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
- UCIBIO-Applied Molecular Biosciences Unit, Chemistry and Life Sciences Departments, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
| | - Susana P Gaudêncio
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
- UCIBIO-Applied Molecular Biosciences Unit, Chemistry and Life Sciences Departments, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
| | - Cristiana A V Torres
- Associate Laboratory i4HB, Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
- UCIBIO-Applied Molecular Biosciences Unit, Chemistry and Life Sciences Departments, NOVA School of Science and Technology, NOVA University of Lisbon, 2819-516 Almada, Portugal
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Serafim B, Bernardino AR, Freitas F, Torres CAV. Recent Developments in the Biological Activities, Bioproduction, and Applications of Pseudomonas spp. Phenazines. Molecules 2023; 28:molecules28031368. [PMID: 36771036 PMCID: PMC9919295 DOI: 10.3390/molecules28031368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/20/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Phenazines are a large group of heterocyclic nitrogen-containing compounds with demonstrated insecticidal, antimicrobial, antiparasitic, and anticancer activities. These natural compounds are synthesized by several microorganisms originating from diverse habitats, including marine and terrestrial sources. The most well-studied producers belong to the Pseudomonas genus, which has been extensively investigated over the years for its ability to synthesize phenazines. This review is focused on the research performed on pseudomonads' phenazines in recent years. Their biosynthetic pathways, mechanism of regulation, production processes, bioactivities, and applications are revised in this manuscript.
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Affiliation(s)
- Bruno Serafim
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2825-149 Caparica, Portugal
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2825-149 Caparica, Portugal
| | - Ana R. Bernardino
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2825-149 Caparica, Portugal
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2825-149 Caparica, Portugal
| | - Filomena Freitas
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2825-149 Caparica, Portugal
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2825-149 Caparica, Portugal
| | - Cristiana A. V. Torres
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2825-149 Caparica, Portugal
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2825-149 Caparica, Portugal
- Correspondence:
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Gil CV, Rebocho AT, Esmail A, Sevrin C, Grandfils C, Torres CAV, Reis MAM, Freitas F. Characterization of the Thermostable Biosurfactant Produced by Burkholderia thailandensis DSM 13276. Polymers (Basel) 2022; 14:polym14102088. [PMID: 35631971 PMCID: PMC9143496 DOI: 10.3390/polym14102088] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 05/15/2022] [Accepted: 05/16/2022] [Indexed: 02/04/2023] Open
Abstract
Biosurfactants synthesized by microorganisms represent safe and sustainable alternatives to the use of synthetic surfactants, due to their lower toxicity, better biodegradability and biocompatibility, and their production from low-cost feedstocks. In line with this, the present study describes the physical, chemical, and functional characterization of the biopolymer secreted by the bacterium Burkholderia thailandensis DSM 13276, envisaging its validation as a biosurfactant. The biopolymer was found to be a glycolipopeptide with carbohydrate and protein contents of 33.1 ± 6.4% and 23.0 ± 3.2%, respectively. Galactose, glucose, rhamnose, mannose, and glucuronic acid were detected in the carbohydrate moiety at a relative molar ratio of 4:3:2:2:1. It is a high-molecular-weight biopolymer (1.0 × 107 Da) with low polydispersity (1.66), and forms aqueous solutions with shear-thinning behavior, which remained after autoclaving. The biopolymer has demonstrated a good emulsion-stabilizing capacity towards different hydrophobic compounds, namely, benzene, almond oil, and sunflower oil. The emulsions prepared with the biosurfactant, as well as with its autoclaved solution, displayed high emulsification activity (>90% and ~50%, respectively). Moreover, the almond and sunflower oil emulsions stabilized with the biosurfactant were stable for up to 4 weeks, which further supports the potential of this novel biopolymer for utilization as a natural bioemulsifier.
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Affiliation(s)
- Cátia V. Gil
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 1099-085 Caparica, Portugal; (C.V.G.); (A.T.R.); (A.E.); (M.A.M.R.); (F.F.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829–516 Caparica, Portugal
| | - Ana Teresa Rebocho
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 1099-085 Caparica, Portugal; (C.V.G.); (A.T.R.); (A.E.); (M.A.M.R.); (F.F.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829–516 Caparica, Portugal
| | - Asiyah Esmail
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 1099-085 Caparica, Portugal; (C.V.G.); (A.T.R.); (A.E.); (M.A.M.R.); (F.F.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829–516 Caparica, Portugal
| | - Chantal Sevrin
- Interfaculty Research Centre of Biomaterials (CEIB), University of Liège, B-4000 Liège, Belgium; (C.S.); (C.G.)
| | - Christian Grandfils
- Interfaculty Research Centre of Biomaterials (CEIB), University of Liège, B-4000 Liège, Belgium; (C.S.); (C.G.)
| | - Cristiana A. V. Torres
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 1099-085 Caparica, Portugal; (C.V.G.); (A.T.R.); (A.E.); (M.A.M.R.); (F.F.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829–516 Caparica, Portugal
- Correspondence: ; Tel.: +351-212948300
| | - Maria A. M. Reis
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 1099-085 Caparica, Portugal; (C.V.G.); (A.T.R.); (A.E.); (M.A.M.R.); (F.F.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829–516 Caparica, Portugal
| | - Filomena Freitas
- Laboratory i4HB—Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 1099-085 Caparica, Portugal; (C.V.G.); (A.T.R.); (A.E.); (M.A.M.R.); (F.F.)
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829–516 Caparica, Portugal
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Aloui H, Khomlaem C, Torres CAV, Freitas F, Reis MAM, Kim BS. Enhanced co-production of medium-chain-length polyhydroxyalkanoates and phenazines from crude glycerol by high cell density cultivation of Pseudomonas chlororaphis in membrane bioreactor. Int J Biol Macromol 2022; 211:545-555. [PMID: 35577193 DOI: 10.1016/j.ijbiomac.2022.05.089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/09/2022] [Accepted: 05/10/2022] [Indexed: 11/05/2022]
Abstract
Enhanced co-production of medium-chain-length polyhydroxyalkanoates (mcl-PHA) and extracellular phenazines was assessed through a high cell density cultivation of Pseudomonas chlororaphis subsp. aurantiaca (DSM 19603) in a membrane bioreactor using crude glycerol as a fermentative substrate. A maximum dry cell weight (DCW) of 59.25 ± 0.31 g/L was achieved at 90 h of cultivation with a maximum mcl-PHA and extracellular phenazines concentrations of respectively 19.05 ± 0.04 g/L (32.16% of DCW) and 79.42 ± 0.35 mg/L. mcl-PHA concentration achieved through cell retention culture was 28.43-folds higher than that obtained by batch culture. Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry, and 1H nuclear magnetic resonance analysis identified the produced PHA as a mcl-PHA copolymer of 3-hydroxyhexanoate (0.68%), 3-hydroxyoctanoate (7.76%), 3-hydroxydecanoate (49.18%), 3-hydroxydodecanoate (4.89%), and 3-hydroxytetradecanoate (37.50%). The mcl-PHA exhibited a highly amorphous structure with low crystallinity index (4.19%) and high thermal stability. This is the first report on the enhanced co-production of mcl-PHA and phenazines in a membrane bioreactor.
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Affiliation(s)
- Hajer Aloui
- Department of Chemical Engineering, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea
| | - Chanin Khomlaem
- Department of Chemical Engineering, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea
| | - Cristiana A V Torres
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - Filomena Freitas
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - Maria A M Reis
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - Beom Soo Kim
- Department of Chemical Engineering, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea.
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Esmail A, Rebocho AT, Marques AC, Silvestre S, Gonçalves A, Fortunato E, Torres CAV, Reis MAM, Freitas F. Bioconversion of Terephthalic Acid and Ethylene Glycol Into Bacterial Cellulose by Komagataeibacter xylinus DSM 2004 and DSM 46604. Front Bioeng Biotechnol 2022; 10:853322. [PMID: 35480983 PMCID: PMC9036990 DOI: 10.3389/fbioe.2022.853322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 03/14/2022] [Indexed: 11/16/2022] Open
Abstract
Komagataeibacter xylinus strains DSM 2004 and DSM 46604 were evaluated for their ability to grow and produce bacterial cellulose (BC) upon cultivation on terephthalic acid (TA) and ethylene glycol (EG), which are monomers of the petrochemical-derived plastic polyethylene terephthalate (PET). Both strains were able to utilize TA, EG, and their mixtures for BC synthesis, with different performances. K. xylinus DSM 2004 achieved higher BC production from TA (0.81 ± 0.01 g/L), EG (0.64 ± 0.02 g/L), and TA + EG mixtures (0.6 ± 0.1 g/L) than strain DSM 46604. The latter was unable to utilize EG as the sole carbon source and reached a BC production of 0.16 ± 0.01 g/L and 0.23 ± 0.1 g/L from TA alone or TA + EG mixtures, respectively. Further supplementing the media with glucose enhanced BC production by both strains. During cultivation on media containing TA and EG, rapid pH drop due to metabolization of EG into acidic compounds led to some precipitation of TA that was impregnated into the BC pellicles. An adaptation of the downstream procedure involving BC dissolution in NaOH was used for the recovery of pure BC. The different medium composition tested, as well as the downstream procedure, impacted the BC pellicles’ physical properties. Although no variation in terms of the chemical structure were observed, differences in crystallinity degree and microstructure of the produced BC were observed. The BC produced by K. xylinus DSM 2004 had a higher crystallinity (19–64%) than that of the strain DSM 46604 (17–53%). Moreover, the scanning electron microscopy analysis showed a higher fiber diameter for K. xylinus DSM 2004 BC (46–56 nm) than for K. xylinus DSM 46604 (37–49 nm). Dissolution of BC in NaOH did not influence the chemical structure; however, it led to BC conversion from type I to type II, as well as a decrease in crystallinity. These results demonstrate that PET monomers, TA and EG, can be upcycled into a value-added product, BC, presenting an approach that will contribute to lessening the environmental burden caused by plastic disposal in the environment.
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Affiliation(s)
- Asiyah Esmail
- Associate Laboratory Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal.,UCIBIO-Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal
| | - Ana T Rebocho
- Associate Laboratory Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal.,UCIBIO-Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal
| | - Ana C Marques
- Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, Caparica, Portugal
| | - Sara Silvestre
- Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, Caparica, Portugal
| | - Alexandra Gonçalves
- Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, Caparica, Portugal
| | - Elvira Fortunato
- Department of Materials Science, School of Science and Technology, NOVA University Lisbon and CEMOP/UNINOVA, Caparica, Portugal
| | - Cristiana A V Torres
- Associate Laboratory Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal.,UCIBIO-Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal
| | - Maria A M Reis
- Associate Laboratory Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal.,UCIBIO-Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal
| | - Filomena Freitas
- Associate Laboratory Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal.,UCIBIO-Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Portugal
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Joulak I, Concórdio-Reis P, Torres CAV, Sevrin C, Grandfils C, Attia H, Freitas F, Reis MAM, Azabou S. Sustainable use of agro-industrial wastes as potential feedstocks for exopolysaccharide production by selected Halomonas strains. Environ Sci Pollut Res Int 2022; 29:22043-22055. [PMID: 34773587 DOI: 10.1007/s11356-021-17207-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 10/21/2021] [Indexed: 06/13/2023]
Abstract
Large quantities of waste biomass are generated annually worldwide by many industries and are vastly underutilized. However, these wastes contain sugars and other dissolved organic matter and therefore can be exploited to produce microbial biopolymers. In this study, four selected Halomonas strains, namely, Halomonas caseinilytica K1, Halomonas elongata K4, Halomonas smyrnensis S3, and Halomonas halophila S4, were investigated for the production of exopolysaccharides (EPS) using low-cost agro-industrial wastes as the sole carbon source: cheese whey, grape pomace, and glycerol. Interestingly, both yield and monosaccharide composition of EPS were affected by the carbon source. Glucose, mannose, galactose, and rhamnose were the predominant monomers, but their relative molar ratio was different. Similarly, the average molecular weight of the synthesized EPS was affected, ranging from 54.5 to 4480 kDa. The highest EPS concentration (446 mg/L) was obtained for H. caseinilytica K1 grown on cheese whey that produced an EPS composed mostly of galactose, rhamnose, glucose, and mannose, with lower contents of galacturonic acid, ribose, and arabinose and with a molecular weight of 54.5 kDa. Henceforth, the ability of Halomonas strains to use cost-effective substrates, especially cheese whey, is a promising approach for the production of EPS with distinct physicochemical properties suitable for various applications.
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Affiliation(s)
- Ichrak Joulak
- Laboratoire Analyse, Valorisation Et Sécurité Des Aliments, Université de Sfax, ENIS, 3038, Sfax, Tunisia
| | - Patrícia Concórdio-Reis
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Lisbon, Portugal
- UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Lisbon, Portugal
| | - Cristiana A V Torres
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Lisbon, Portugal
- UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Lisbon, Portugal
| | - Chantal Sevrin
- Interfaculty Research Centre of Biomaterials (CEIB), University of Liège, Liège, Belgium
| | - Christian Grandfils
- Interfaculty Research Centre of Biomaterials (CEIB), University of Liège, Liège, Belgium
| | - Hamadi Attia
- Laboratoire Analyse, Valorisation Et Sécurité Des Aliments, Université de Sfax, ENIS, 3038, Sfax, Tunisia
| | - Filomena Freitas
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Lisbon, Portugal
- UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Lisbon, Portugal
| | - Maria A M Reis
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, Caparica, Lisbon, Portugal
- UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, Caparica, Lisbon, Portugal
| | - Samia Azabou
- Laboratoire Analyse, Valorisation Et Sécurité Des Aliments, Université de Sfax, ENIS, 3038, Sfax, Tunisia.
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Guerreiro BM, Silva JC, Torres CAV, Alves VD, Lima JC, Reis MAM, Freitas F. Development of a Cryoprotective Formula Based on the Fucose-Containing Polysaccharide FucoPol. ACS Appl Bio Mater 2021; 4:4800-4808. [PMID: 35007029 DOI: 10.1021/acsabm.1c00007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
This study reports the performance of the polysaccharide FucoPol as an enhancer of cryoprotective formulations. FucoPol at a concentration of 0.25% (w/v) was added to several normothermic Dulbecco-derived solutions and hypothermic Euro-Collins, Custodiol-HTK, and Unisol-CV media, substituting some constituents in the latter class to develop FucoPol-based formulations that were tested for their ability to cryopreserve Vero cells. Supplementation yielded post-thaw cell recovery enhancements of at least 70% and averaged at 82%. The FucoPol-supplemented formulations Dulbecco(+)+FP and Unisol-CVS3 achieved cell viabilities capable of competing with the commercial cryogenic formula CryoStor CS5. Particularly in Unisol-CVS3, mannitol, glucose, gluconate, and dextran were all substituted by 0.25% FucoPol, and still, a similar viability was achieved. Multiparametric correlation clustering showed that FucoPol cryoprotection synergizes best with K+, Ca2+, and Cl- in its microenvironment. Component substitution analysis demonstrated that FucoPol acts consistently as a cryoprotectant, an impermeant, and a colloidal stabilizer, providing a combined alternative to glucose, mannitol, gluconate, and dextran, thus highlighting its potential in the development of high-performing cryoprotective formulas.
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Affiliation(s)
- Bruno M Guerreiro
- UCIBIO-REQUIMTE, Chemistry Department, NOVA School of Sciences and Technology, Caparica 2829-516, Portugal.,CENIMAT/I3N, Physics Department, NOVA School of Sciences and Technology, Caparica 2829-516, Portugal.,LAQV-REQUIMTE, Chemistry Department, NOVA School of Sciences and Technology, Caparica 2829-516, Portugal
| | - Jorge C Silva
- CENIMAT/I3N, Physics Department, NOVA School of Sciences and Technology, Caparica 2829-516, Portugal
| | - Cristiana A V Torres
- UCIBIO-REQUIMTE, Chemistry Department, NOVA School of Sciences and Technology, Caparica 2829-516, Portugal
| | - Vítor D Alves
- LEAF - Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, Lisboa 1349-017, Portugal
| | - João C Lima
- LAQV-REQUIMTE, Chemistry Department, NOVA School of Sciences and Technology, Caparica 2829-516, Portugal
| | - Maria A M Reis
- UCIBIO-REQUIMTE, Chemistry Department, NOVA School of Sciences and Technology, Caparica 2829-516, Portugal
| | - Filomena Freitas
- UCIBIO-REQUIMTE, Chemistry Department, NOVA School of Sciences and Technology, Caparica 2829-516, Portugal
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9
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Valério R, Bernardino ARS, Torres CAV, Brazinha C, Tavares ML, Crespo JG, Reis MAM. Feeding strategies to optimize vanillin production by Amycolatopsis sp. ATCC 39116. Bioprocess Biosyst Eng 2021; 44:737-747. [PMID: 33389106 DOI: 10.1007/s00449-020-02482-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 11/10/2020] [Indexed: 01/28/2023]
Abstract
The growing consumer demand for natural products led to an increasing interest in vanillin production by biotechnological routes. In this work, the biotechnological vanillin production by Amycolatopsis sp. ATCC 39116 is studied using ferulic acid as precursor, aiming to achieve maximized vanillin productivities. During biotech-vanillin production, the effects of glucose, vanillin and ferulic acid concentrations in the broth proved to be relevant for vanillin productivity. Concerning glucose, its presence in the broth during the production phase avoids vanillin conversion to vanillic acid and, consequently, increases vanillin production. To avoid the accumulation of vanillin up to a toxic concentration level, a multiple-pulse-feeding strategy is implemented, with intercalated vanillin removal from the broth and biomass recovery. This strategy turned out fruitful, leading to 0.46 g L-1 h-1 volumetric productivity of vanillin of and a production yield of 0.69 gvanillin gferulic acid-1, which are among the highest values reported in the literature for non-modified bacteria.
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Affiliation(s)
- Rita Valério
- UCIBIO-REQUIMTE, Chemistry Department, FCT/Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal.,LAQV-REQUIMTE, Chemistry Department, FCT/Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal
| | - Ana R S Bernardino
- UCIBIO-REQUIMTE, Chemistry Department, FCT/Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal
| | - Cristiana A V Torres
- UCIBIO-REQUIMTE, Chemistry Department, FCT/Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal.
| | - Carla Brazinha
- LAQV-REQUIMTE, Chemistry Department, FCT/Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal
| | - Maria L Tavares
- Copam-Companhia Portuguesa de Amidos SA, 2695-722, S. João da Talha, Portugal
| | - João G Crespo
- LAQV-REQUIMTE, Chemistry Department, FCT/Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal
| | - Maria A M Reis
- UCIBIO-REQUIMTE, Chemistry Department, FCT/Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal
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Freitas F, Torres CAV, Reis MAM. Engineering aspects of microbial exopolysaccharide production. Bioresour Technol 2017; 245:1674-1683. [PMID: 28554522 DOI: 10.1016/j.biortech.2017.05.092] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/13/2017] [Accepted: 05/15/2017] [Indexed: 06/07/2023]
Abstract
Although the ability to secrete exopolysaccharides (EPS) is widespread among microorganisms, only a few bacterial (e.g. xanthan, levan, dextran) and fungal (e.g. pullulan) EPS have reached full commercialization. During the last years, other microbial EPS producers have been the subject of extensive research, including endophytes, extremophiles, microalgae and Cyanobacteria, as well as mixed microbial consortia. Those studies have demonstrated the great potential of such microbial systems to generate biopolymers with novel chemical structures and distinctive functional properties. In this work, an overview of the bioprocesses developed for EPS production by the wide diversity of reported microbial producers is presented, including their development and scale-up. Bottlenecks that currently hinder microbial EPS development are identified, along with future prospects for further advancement.
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Affiliation(s)
- Filomena Freitas
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Cristiana A V Torres
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Maria A M Reis
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal.
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Lourenço SC, Torres CAV, Nunes D, Duarte P, Freitas F, Reis MAM, Fortunato E, Moldão-Martins M, da Costa LB, Alves VD. Using a bacterial fucose-rich polysaccharide as encapsulation material of bioactive compounds. Int J Biol Macromol 2017; 104:1099-1106. [PMID: 28687391 DOI: 10.1016/j.ijbiomac.2017.07.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 06/06/2017] [Accepted: 07/03/2017] [Indexed: 12/11/2022]
Abstract
The potential of a bacterial exopolysaccharide named FucoPol, produced by the bacterium Enterobacter A47, as encapsulation matrix was explored. Spherical capsules with a smooth surface were produced by spray drying. The obtained microcapsules had average diameters ranging from 0.5 to 26.7μm and presented thin walls (thickness from 222 to 1094nm). The capsules were loaded with two bioactive compounds: gallic acid (GA) and oregano essential oil (OEO). Both bioactive materials were encapsulated in FucoPol particles, retaining their antioxidant activity after the drying process. Release studies showed that GA release in simulated gastric and intestinal fluids was faster than that of OEO, envisaging that the latter had established stronger interactions with the polymer matrix. These results suggest that FucoPol has a good potential for use as encapsulating material of bioactive compounds for application in several areas, including food, cosmetic or pharmaceutical products.
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Affiliation(s)
- Sofia C Lourenço
- LEAF, Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
| | - Cristiana A V Torres
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Daniela Nunes
- CENIMAT/i3N, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa and CEMOP-UNINOVA, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Paulo Duarte
- CENIMAT/i3N, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa and CEMOP-UNINOVA, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Filomena Freitas
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Maria A M Reis
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Elvira Fortunato
- CENIMAT/i3N, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa and CEMOP-UNINOVA, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Margarida Moldão-Martins
- LEAF, Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
| | - Luísa Beirão da Costa
- LEAF, Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
| | - Vítor D Alves
- LEAF, Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal.
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Marques R, von Stosch M, Portela RMC, Torres CAV, Antunes S, Freitas F, Reis MAM, Oliveira R. Hybrid modeling of microbial exopolysaccharide (EPS) production: The case of Enterobacter A47. J Biotechnol 2017; 246:61-70. [PMID: 28153767 DOI: 10.1016/j.jbiotec.2017.01.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 01/13/2017] [Accepted: 01/27/2017] [Indexed: 11/25/2022]
Abstract
Enterobacter A47 is a bacterium that produces high amounts of a fucose-rich exopolysaccharide (EPS) from glycerol residue of the biodiesel industry. The fed-batch process is characterized by complex non-linear dynamics with highly viscous pseudo-plastic rheology due to the accumulation of EPS in the culture medium. In this paper, we study hybrid modeling as a methodology to increase the predictive power of models for EPS production optimization. We compare six hybrid structures that explore different levels of knowledge-based and machine-learning model components. Knowledge-based components consist of macroscopic material balances, Monod type kinetics, cardinal temperature and pH (CTP) dependency and power-law viscosity models. Unknown dependencies are set to be identified by a feedforward artificial neural network (ANN). A semiparametric identification schema is applied resorting to a data set of 13 independent fed-batch experiments. A parsimonious hybrid model was identified that describes the dynamics of the 13 experiments with the same parameterization. The final model is specific to Enterobacter A47 but can be easily extended to other microbial EPS processes.
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Affiliation(s)
- Rodolfo Marques
- LAQV-REQUIMTE, Systems Biology and Engineering Group, Chemistry Department, FCT/Universidade Nova de Lisboa, 2829-516 Campus Caparica, Portugal
| | - Moritz von Stosch
- LAQV-REQUIMTE, Systems Biology and Engineering Group, Chemistry Department, FCT/Universidade Nova de Lisboa, 2829-516 Campus Caparica, Portugal
| | - Rui M C Portela
- LAQV-REQUIMTE, Systems Biology and Engineering Group, Chemistry Department, FCT/Universidade Nova de Lisboa, 2829-516 Campus Caparica, Portugal
| | - Cristiana A V Torres
- UCIBIO-REQUIMTE, Biochemical Engineering Group, Chemistry Department, FCT/Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Sílvia Antunes
- UCIBIO-REQUIMTE, Biochemical Engineering Group, Chemistry Department, FCT/Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Filomena Freitas
- UCIBIO-REQUIMTE, Biochemical Engineering Group, Chemistry Department, FCT/Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Maria A M Reis
- UCIBIO-REQUIMTE, Biochemical Engineering Group, Chemistry Department, FCT/Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | - Rui Oliveira
- LAQV-REQUIMTE, Systems Biology and Engineering Group, Chemistry Department, FCT/Universidade Nova de Lisboa, 2829-516 Campus Caparica, Portugal.
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Torres CAV, Antunes S, Ricardo AR, Grandfils C, Alves VD, Freitas F, Reis MAM. Study of the interactive effect of temperature and pH on exopolysaccharide production by Enterobacter A47 using multivariate statistical analysis. Bioresour Technol 2012; 119:148-156. [PMID: 22728195 DOI: 10.1016/j.biortech.2012.05.106] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 04/26/2012] [Accepted: 05/22/2012] [Indexed: 06/01/2023]
Abstract
Enterobacter A47 synthesizes fucose-containing exopolysaccharides (EPS). Maximum EPS production (>7.00 g L(-1)) was obtained for temperature and pH within 25-35°C and 6.0-8.0, respectively. Under these conditions, the polymers contained over 30% fucose. Glucose, galactose, and glucuronic acid contents were about 28%, 25%, and 10%, respectively, and the total acyl groups content was about 20 wt.%. The average molecular weight (Mw) was around 4.0 × 10(6). Outside the optimal temperature and pH ranges, fucose, galactose and glucuronic acid, and the total acyl group contents were reduced, while the glucose content increased, new monomers (rhamnose and glucosamine) were detected, and the Mw increased to ≥ 1.10 × 10(7). This study revealed the ability of Enterobacter A47 to synthesize different heteropolysaccharides as a function of pH and temperature, a feature that can be exploited to obtain tailored polymer composition. Moreover, the production of high fucose content EPS was stable for wide pH and temperature ranges, which is important for the envisaged industrial development of the bioprocess.
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Affiliation(s)
- Cristiana A V Torres
- REQUIMTE/CQFB, Chemistry Department, FCT/Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
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Albuquerque MGE, Torres CAV, Reis MAM. Polyhydroxyalkanoate (PHA) production by a mixed microbial culture using sugar molasses: effect of the influent substrate concentration on culture selection. Water Res 2010; 44:3419-33. [PMID: 20427069 DOI: 10.1016/j.watres.2010.03.021] [Citation(s) in RCA: 178] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Revised: 03/18/2010] [Accepted: 03/19/2010] [Indexed: 05/06/2023]
Abstract
In Polyhydroxyalkanoate (PHA) production processes using Mixed Microbial Culture (MMC), the success of the culture selection step determines, to a great extent, the PHA accumulation performance obtained in the final PHA production stage. In this study, the effect of the influent substrate concentration (30-60Cmmol VFA/L) on the selection of a PHA-storing culture using a complex feedstock, fermented sugar molasses, was assessed. At 30 and 45Cmmol VFA/L, substrate concentration impacted on the process kinetics through a substrate dependent kinetic limitation effect. However, further increasing the carbon substrate concentration to 60Cmmol VFA/L, resulted in an unforeseen growth limitation effect associated with a micronutrient deficiency of the fermented feedstock (magnesium) and high operating pH. Struvite precipitation caused a nutrient limitation which prevented biomass concentration increase, thus causing the feast to famine length ratio to vary in the selection reactor, with subsequent impact on the selective pressure for PHA-storing organisms. A highly dynamic response of the selected population to transient conditions of feast to famine ratio, in the range of 0.21-1.1, was observed. Kinetic (limiting concentration of carbon source) and physiological (loss of internal growth limitation due to the shorter length of famine phase) effects, resulting from variation of the influent substrate concentration, were subsequently demonstrated in batch studies. The culture selected at an influent substrate concentration of 45Cmmol VFA/L showed the best PHA-storing capacity since neither substrate concentration nor feast to famine ratio were limiting factors. This culture, highly enriched in PHA-storing organisms (88%), reached a maximum PHA content of 74.6%.
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Affiliation(s)
- M G E Albuquerque
- REQUIMTE/CQFB, Department of Chemistry, FCT, Universidade Nova de Lisboa, P-2829-516 Caparica, Portugal
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