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Frank C, Emmerstorfer-Augustin A, Rath T, Trimmel G, Nachtnebel M, Stelzer F. Bio-Polyester/Rubber Compounds: Fabrication, Characterization, and Biodegradation. Polymers (Basel) 2023; 15:2593. [PMID: 37376240 DOI: 10.3390/polym15122593] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 05/23/2023] [Accepted: 05/26/2023] [Indexed: 06/29/2023] Open
Abstract
Biobased and biodegradable polymers (BBDs) such as poly(3-hydroxy-butyrate), PHB, and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) are considered attractive alternatives to fossil-based plastic materials since they are more environmentally friendly. One major problem with these compounds is their high crystallinity and brittleness. In order to generate softer materials without using fossil-based plasticizers, the suitability of natural rubber (NR) as an impact modifier was investigated in PHBV blends. Mixtures with varying proportions of NR and PHBV were generated, and samples were prepared by mechanical mixing (roll mixer and/or internal mixer) and cured by radical C-C crosslinking. The obtained specimens were investigated with respect to their chemical and physical characteristics, applying a variety of different methods such as size exclusion chromatography, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermal analysis, XRD, and mechanical testing. Our results clearly indicate that NR-PHBV blends exhibit excellent material characteristics including high elasticity and durability. Additionally, biodegradability was tested by applying heterologously produced and purified depolymerases. pH shift assays and morphology analyses of the surface of depolymerase-treated NR-PHBV through electron scanning microscopy confirmed the enzymatic degradation of PHBV. Altogether, we prove that NR is highly suitable to substitute fossil-based plasticizers; NR-PHBV blends are biodegradable and, hence, should be considered as interesting materials for a great number of applications.
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Affiliation(s)
- Carina Frank
- Acib-GmbH, Krenngasse 32, A-8010 Graz, Austria
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria
| | - Anita Emmerstorfer-Augustin
- Acib-GmbH, Krenngasse 32, A-8010 Graz, Austria
- Institute for Molecular Biotechnology, Graz University of Technology, NAWI Graz, BioTechMed-Graz, Petersgasse 14, A-8010 Graz, Austria
| | - Thomas Rath
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria
| | - Gregor Trimmel
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria
| | - Manfred Nachtnebel
- Graz Centre for Electron Microscopy, Steyrergasse 17, A-8010 Graz, Austria
| | - Franz Stelzer
- Acib-GmbH, Krenngasse 32, A-8010 Graz, Austria
- Institute for Chemistry and Technology of Materials, Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria
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Kumar V, Lakkaboyana SK, Tsouko E, Maina S, Pandey M, Umesh M, Singhal B, Sharma N, Awasthi MK, Andler R, Jayaraj I, Yuzir A. Commercialization potential of agro-based polyhydroxyalkanoates biorefinery: A technical perspective on advances and critical barriers. Int J Biol Macromol 2023; 234:123733. [PMID: 36801274 DOI: 10.1016/j.ijbiomac.2023.123733] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 02/12/2023] [Accepted: 02/13/2023] [Indexed: 02/18/2023]
Abstract
The exponential increase in the use and careless discard of synthetic plastics has created an alarming concern over the environmental health due to the detrimental effects of petroleum based synthetic polymeric compounds. Piling up of these plastic commodities on various ecological niches and entry of their fragmented parts into soil and water has clearly affected the quality of these ecosystems in the past few decades. Among the many constructive strategies developed to tackle this global issue, use of biopolymers like polyhydroxyalkanoates as sustainable alternatives for synthetic plastics has gained momentum. Despite their excellent material properties and significant biodegradability, polyhydroxyalkanoates still fails to compete with their synthetic counterparts majorly due to the high cost associated with their production and purification thereby limiting their commercialization. Usage of renewable feedstocks as substrates for polyhydroxyalkanoates production has been the thrust area of research to attain the sustainability tag. This review work attempts to provide insights about the recent developments in the production of polyhydroxyalkanoates using renewable feedstock along with various pretreatment methods used for substrate preparation for polyhydroxyalkanoates production. Further, the application of blends based on polyhydroxyalkanoates, and the challenges associated with the waste valorization based polyhydroxyalkanoates production strategy is elaborated in this review work.
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Affiliation(s)
- Vinay Kumar
- Ecotoxicity and Bioconversion Laboratory, Department of Community Medicine, Saveetha Medical College and Hospital, Saveetha Institute of Medical and Technical Sciences (SIMATS), Chennai, Thandalam 602105, India; Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India.
| | - Sivarama Krishna Lakkaboyana
- Department of Chemistry, Vel Tech Rangarajan Dr. Sagunthala R&D Institute of Science and Technology, Avadi, Chennai 600062, India; Department of Chemical and Environmental Engineering (ChEE), Malaysia-Japan International Institute of Technology (MJIIT)-Universiti Technologi Malaysia, Jalan Sultan Yahya Petra, 54100 Kuala Lumpur, Malaysia
| | - Erminta Tsouko
- Department of Food Science and Nutrition, School of Environment, University of the Aegean, Metropolite Ioakeim 2, 81400, Myrina, Lemnos, Greece
| | - Sofia Maina
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece
| | - Muskan Pandey
- School of Biotechnology, Gautam Buddha University, Greater Noida, U.P., India
| | - Mridul Umesh
- Department of Life Sciences, CHRIST (Deemed to be University), Hosur Road, Bengaluru 560029, Karnataka, India
| | - Barkha Singhal
- School of Biotechnology, Gautam Buddha University, Greater Noida, U.P., India
| | - Neha Sharma
- Metagenomics and Bioprocess Design Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Mukesh Kumar Awasthi
- College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, PR China
| | - Rodrigo Andler
- Escuela de Ingeniería en Biotecnología, Centro de Biotecnología de los Recursos Naturales (Cenbio), Universidad Católica del Maule, Chile
| | - Iyyappan Jayaraj
- Department of Bioengineering, Institute of Biotechnology, Saveetha School of Engineering, SIMATS, Chennai 602105, India
| | - Ali Yuzir
- Department of Chemical and Environmental Engineering (ChEE), Malaysia-Japan International Institute of Technology (MJIIT)-Universiti Technologi Malaysia, Jalan Sultan Yahya Petra, 54100 Kuala Lumpur, Malaysia
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Jeon JM, Park SJ, Son YS, Yang YH, Yoon JJ. Bioconversion of Mixed Alkanes to Polyhydroxyalkanoate by Pseudomonas resinovornas: Upcycling of Pyrolysis Oil from Waste-Plastic. Polymers (Basel) 2022; 14:polym14132624. [PMID: 35808670 PMCID: PMC9268961 DOI: 10.3390/polym14132624] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/21/2022] [Accepted: 06/22/2022] [Indexed: 11/16/2022] Open
Abstract
Polyhydroxyalkanoate (PHA) is a biodegradable plastic that can be used to replace petroleum-based plastic. In addition, as a medium-chain-length PHA (mcl-PHA), it can be used to provide elastomeric properties in specific applications. Because of these characteristics, recently, there has been much research on mcl-PHA production using inexpensive biomass materials as substrates. In this study, mcl-PHA producers were screened using alkanes (n-octane, n-decane, and n-dodecane) as sources of carbon. The amount of PHA produced by Pseudomonas resinovorans using sole n-octane, n-decane, or n-dodecane was 0.48 g/L, 0.27 g/L, or 0.07 g/L, respectively, while that produced using mixed alkane was 0.74 g/L. As a larger amount of PHA was produced using mixed alkane compared with sole alkane, a statistical mixture analysis was used to determine the optimal ratio of alkanes in the mixture. The optimal ratio predicted by the analysis was a medium with 9.15% n-octane, 6.44% n-decane, and 4.29% n-dodecane. In addition, through several concentration-specific experiments, the optimum concentrations of nitrogen and phosphorus for cell growth and maximum PHA production were determined as 0.05% and 1.0%, respectively. Finally, under the determined optimal conditions, 2.1 g/L of mcl-PHA and 60% PHA content were obtained using P. resinovorans in a 7 L fermenter.
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Affiliation(s)
- Jong-Min Jeon
- Green & Sustainable Materials Research and Development Department, Korea Institute of Industrial Technology (KITECH), Cheonan 31056, Korea; (J.-M.J.); (S.-J.P.); (Y.-S.S.)
| | - So-Jin Park
- Green & Sustainable Materials Research and Development Department, Korea Institute of Industrial Technology (KITECH), Cheonan 31056, Korea; (J.-M.J.); (S.-J.P.); (Y.-S.S.)
- School of Industrial technology, University of Science and Technology (UST), Daejeon 34113, Korea
| | - Ye-Seung Son
- Green & Sustainable Materials Research and Development Department, Korea Institute of Industrial Technology (KITECH), Cheonan 31056, Korea; (J.-M.J.); (S.-J.P.); (Y.-S.S.)
| | - Yung-Hun Yang
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Korea;
| | - Jeong-Jun Yoon
- Green & Sustainable Materials Research and Development Department, Korea Institute of Industrial Technology (KITECH), Cheonan 31056, Korea; (J.-M.J.); (S.-J.P.); (Y.-S.S.)
- Correspondence: ; Tel.: +82-41-589-8266
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Kettner A, Noll M, Griehl C. Leptolyngbya sp. NIVA-CYA 255, a Promising Candidate for Poly(3-hydroxybutyrate) Production under Mixotrophic Deficiency Conditions. Biomolecules 2022; 12:biom12040504. [PMID: 35454093 PMCID: PMC9030801 DOI: 10.3390/biom12040504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/19/2022] [Accepted: 03/21/2022] [Indexed: 12/01/2022] Open
Abstract
Cyanobacteria are a promising source for the sustainable production of biodegradable bioplastics such as poly(3-hydroxybutyrate) (PHB). The auto-phototrophic biomass formation is based on light and CO2, which is an advantage compared to heterotrophic PHB-producing systems. So far, only a handful of cyanobacterial species suitable for the high-yield synthesis of PHB have been reported. In the present study, the PHB formation, biomass, and elemental composition of Leptolyngbya sp. NIVA-CYA 255 were investigated. Therefore, a three-stage cultivation process was applied, consisting of a growth stage; an N-, P-, and NP-depleted phototrophic stage; and a subsequent mixotrophic deficiency stage, initiated by sodium acetate supplementation. The extracted cyanobacterial PHB was confirmed by FTIR- and GC-MS analyses. Furthermore, the fluorescent dyes LipidGreen2 and Nile red were used for fluorescence-based monitoring and the visualization of PHB. LipidGreen2 was well suited for PHB quantification, while the application of Nile red was limited by fluorescence emission crosstalk with phycocyanin. The highest PHB yields were detected in NP- (325 mg g−1) and N-deficiency (213 mg g−1). The glycogen pool was reduced in all cultures during mixotrophy, while lipid composition was not affected. The highest glycogen yield was formed under N-deficiency (217 mg g−1). Due to the high carbon storage capacity and PHB formation, Leptolyngbya sp. NIVA-CYA 255 is a promising candidate for PHB production. Further work will focus on upscaling to a technical scale and monitoring the formation by LipidGreen2-based fluorometry.
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Affiliation(s)
- Alexander Kettner
- Competence Center Algal Biotechnology, Department of Applied Biosciences and Process Engineering, Anhalt University of Applied Sciences, Bernburger Strasse 55, 06366 Koethen, Germany;
| | - Matthias Noll
- Institute of Bioanalysis, Coburg University of Applied Sciences and Arts, Friedrich-Streib-Str. 2, 96450 Coburg, Germany;
| | - Carola Griehl
- Competence Center Algal Biotechnology, Department of Applied Biosciences and Process Engineering, Anhalt University of Applied Sciences, Bernburger Strasse 55, 06366 Koethen, Germany;
- Correspondence: ; Tel.: +49-(0)-3496-67-2526
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Brown B, Immethun C, Alsiyabi A, Long D, Wilkins M, Saha R. Heterologous phasin expression in Rhodopseudomonas palustris CGA009 for bioplastic production from lignocellulosic biomass. Metab Eng Commun 2022; 14:e00191. [PMID: 35028290 PMCID: PMC8741599 DOI: 10.1016/j.mec.2021.e00191] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 12/17/2021] [Accepted: 12/26/2021] [Indexed: 12/18/2022] Open
Abstract
Rhodopseudomonas palustris CGA009 is a metabolically robust microbe that can utilize lignin breakdown products to produce polyhydroxyalkanoates (PHAs), biopolymers with the potential to replace conventional plastics. Our recent efforts suggest PHA granule formation is a limiting factor for maximum production of the bioplastic poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) by R. palustris. The Phap1 phasin (phaP1) from the PHB-producing model bacterium Cupriavidus necator H16 was expressed in R. palustris with the aim of overproducing PHBV from the lignin breakdown product p-coumarate by fostering smaller and more abundant granules. Expression of phaP1 yielded PHBV production from R. palustris aerobically (0.7 g/L), which does not occur in the wild-type strain, and led to a significantly higher PHBV titer than wild-type anaerobic production (0.41 g/L). The 3HV fractions were also significantly increased under both anaerobic and aerobic conditions, which boosts thermomechanical properties and potential for application. Thus, heterologous phasin expression in R. palustris provides flexibility for industrial processing and could foster compositional changes in copolymers with better thermomechanical properties compared to PHB alone. Heterologous phasin expression in R. palustris fostered aerobic bioplastic production. Offers flexibility for industrial processing of high-value products from lignocellosic biomass. Composition increases in desirable monomer fractions occurred due to phasin expression. Further develops the metabolically robust R. palustris as a biotechnology chassis.
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Affiliation(s)
- Brandi Brown
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA
| | - Cheryl Immethun
- Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Adil Alsiyabi
- Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Dianna Long
- Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Mark Wilkins
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA.,Industrial Agricultural Products Center, University of Nebraska-Lincoln, Lincoln, NE, 68583, USA.,Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Rajib Saha
- Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
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Selli F, Hufenus R, Gooneie A, Erdoğan UH, Perret E. Structure-Property Relationship in Melt-Spun Poly(hydroxybutyrate-co-3-hexanoate) Monofilaments. Polymers (Basel) 2022; 14:200. [PMID: 35012222 PMCID: PMC8747132 DOI: 10.3390/polym14010200] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/13/2021] [Accepted: 12/23/2021] [Indexed: 11/16/2022] Open
Abstract
Poly(hydroxybutyrate-co-3-hexanoate) (PHBH) is a biodegradable thermoplastic polyester with the potential to be used in textile and medical applications. We have aimed at developing an upscalable melt-spinning method to produce fine biodegradable PHBH filaments without the use of an ice water bath or offline drawing techniques. We have evaluated the effect of different polymer grades (mol% 3-hydroxy hexanoate, molecular weight etc.) and production parameters on the tensile properties of melt-spun filaments. PHBH monofilaments (diameter < 130 µm) have been successfully melt-spun and online drawn from three different polymer grades. We report thermal and rheological properties of the polymer grades as well as morphological, thermal, mechanical, and structural properties of the melt-spun filaments thereof. Tensile strengths up to 291 MPa have been achieved. Differences in tensile performance have been correlated to structural differences with wide-angle X-ray diffraction and small-angle X-ray scattering. The measurements obtained have revealed that a synergetic interaction of a highly oriented non-crystalline mesophase with highly oriented α-crystals leads to increased tensile strength. Additionally, the effect of aging on the structure and tensile performance has been investigated.
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Affiliation(s)
- Figen Selli
- Department of Textile Engineering, Dokuz Eylul University, Izmir 35397, Turkey; (F.S.); (U.H.E.)
- Laboratory for Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland; (R.H.); (A.G.)
| | - Rudolf Hufenus
- Laboratory for Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland; (R.H.); (A.G.)
| | - Ali Gooneie
- Laboratory for Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland; (R.H.); (A.G.)
| | - Umit Halis Erdoğan
- Department of Textile Engineering, Dokuz Eylul University, Izmir 35397, Turkey; (F.S.); (U.H.E.)
| | - Edith Perret
- Laboratory for Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland; (R.H.); (A.G.)
- Center for X-ray Analytics, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland
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7
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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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Obulisamy PK, Mehariya S. Polyhydroxyalkanoates from extremophiles: A review. BIORESOURCE TECHNOLOGY 2021; 325:124653. [PMID: 33465644 DOI: 10.1016/j.biortech.2020.124653] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/27/2020] [Accepted: 12/29/2020] [Indexed: 06/12/2023]
Abstract
Polyhydroxyalkanoates (PHAs) are group monomers/heteropolymers that are biodegradable and widely used in biomedical applications. They are considered as alternatives to fossil derived polymers and accumulated by microbes including extremophilic archaea as energy storage inclusions under nutrient limitations. The use of extremophilic archaea for PHA production is an economically viable option for conventional aerobic processes, but less is known about their pathways and PHA accumulation capacities. This review summarized: (a) specific adaptive mechanisms towards extreme environments by extremophiles and specific role of PHAs; (b) understanding of PHA synthesis/metabolism in archaea and specific functional genes; (c) genetic engineering and process engineering approaches required for high-rate PHA production using extremophilic archaea. To conclude, the future studies are suggested to understand the membrane lipids and PHAs accumulation to explain the adaptation mechanism of extremophiles and exploiting it for commercial production of PHAs.
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Affiliation(s)
| | - Sanjeet Mehariya
- Department of Engineering, University of Campania "Luigi Vanvitelli", Real Casa dell'Annunziata, Italy
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Biosynthesis of Polyhydroxyalkanoates (PHAs) by the Valorization of Biomass and Synthetic Waste. Molecules 2020; 25:molecules25235539. [PMID: 33255864 PMCID: PMC7728366 DOI: 10.3390/molecules25235539] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 11/10/2020] [Accepted: 11/12/2020] [Indexed: 12/20/2022] Open
Abstract
Synthetic pollutants are a looming threat to the entire ecosystem, including wildlife, the environment, and human health. Polyhydroxyalkanoates (PHAs) are natural biodegradable microbial polymers with a promising potential to replace synthetic plastics. This research is focused on devising a sustainable approach to produce PHAs by a new microbial strain using untreated synthetic plastics and lignocellulosic biomass. For experiments, 47 soil samples and 18 effluent samples were collected from various areas of Punjab, Pakistan. The samples were primarily screened for PHA detection on agar medium containing Nile blue A stain. The PHA positive bacterial isolates showed prominent orange-yellow fluorescence on irradiation with UV light. They were further screened for PHA estimation by submerged fermentation in the culture broth. Bacterial isolate 16a produced maximum PHA and was identified by 16S rRNA sequencing. It was identified as Stenotrophomonas maltophilia HA-16 (MN240936), reported first time for PHA production. Basic fermentation parameters, such as incubation time, temperature, and pH were optimized for PHA production. Wood chips, cardboard cutouts, plastic bottle cutouts, shredded polystyrene cups, and plastic bags were optimized as alternative sustainable carbon sources for the production of PHAs. A vital finding of this study was the yield obtained by using plastic bags, i.e., 68.24 ± 0.27%. The effective use of plastic and lignocellulosic waste in the cultivation medium for the microbial production of PHA by a novel bacterial strain is discussed in the current study.
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Shahid S, Razzaq S, Farooq R, Nazli ZIH. Polyhydroxyalkanoates: Next generation natural biomolecules and a solution for the world's future economy. Int J Biol Macromol 2020; 166:297-321. [PMID: 33127548 DOI: 10.1016/j.ijbiomac.2020.10.187] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 10/21/2020] [Accepted: 10/23/2020] [Indexed: 02/08/2023]
Abstract
Petrochemical plastics have become a cause of pollution for decades and finding alternative plastics that are environmental friendly. Polyhydroxyalkanoate (PHA), a biopolyester produced by microbial cells, has characteristics (biocompatible, biodegradable, non-toxic) that make it appropriate as a biodegradable plastic substance. The different forms of PHA make it suitable to a wide choice of products, from packaging materials to biomedical applications. The major challenge in commercialization of PHA is the cost of manufacturing. There are a lot of factors that could affect the efficiency of a development method. The development of new strategic parameters for better synthesis, including consumption of low cost carbon substrates, genetic modification of PHA-producing strains, and fermentational strategies are discussed. Recently, many efforts have been made to develop a method for the cost-effective production of PHAs. The isolation, analysis as well as characterization of PHAs are significant factors for any developmental process. Due to the biodegradable and biocompatible properties of PHAs, they are majorly used in biomedical applications such as vascular grafting, heart tissue engineering, skin tissue repairing, liver tissue engineering, nerve tissue engineering, bone tissue engineering, cartilage tissue engineering and therapeutic carrier. The emerging and interesting area of research is the development of self-healing biopolymer that could significantly broaden the operational life and protection of the polymeric materials for a broad range of uses. Biodegradable and biocompatible polymers are considered as the green materials in place of petroleum-based plastics in the future.
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Affiliation(s)
- Salma Shahid
- Department of Biochemistry, Government College Women University Faisalabad, Pakistan.
| | - Sadia Razzaq
- Department of Chemistry, Government College Women University Faisalabad, Pakistan
| | - Robina Farooq
- Department of Chemistry, Government College Women University Faisalabad, Pakistan
| | - Zill-I-Huma Nazli
- Department of Chemistry, Government College Women University Faisalabad, Pakistan
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