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Zhou W, Bergsma S, Colpa DI, Euverink GJW, Krooneman J. Polyhydroxyalkanoates (PHAs) synthesis and degradation by microbes and applications towards a circular economy. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 341:118033. [PMID: 37156023 DOI: 10.1016/j.jenvman.2023.118033] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 04/15/2023] [Accepted: 04/25/2023] [Indexed: 05/10/2023]
Abstract
Overusing non-degradable plastics causes a series of environmental issues, inferring a switch to biodegradable plastics. Polyhydroxyalkanoates (PHAs) are promising biodegradable plastics that can be produced by many microbes using various substrates from waste feedstock. However, the cost of PHAs production is higher compared to fossil-based plastics, impeding further industrial production and applications. To provide a guideline for reducing costs, the potential cheap waste feedstock for PHAs production have been summarized in this work. Besides, to increase the competitiveness of PHAs in the mainstream plastics economy, the influencing parameters of PHAs production have been discussed. The PHAs degradation has been reviewed related to the type of bacteria, their metabolic pathways/enzymes, and environmental conditions. Finally, the applications of PHAs in different fields have been presented and discussed to induce comprehension on the practical potentials of PHAs.
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Affiliation(s)
- Wen Zhou
- Products and Processes for Biotechnology, Engineering and Technology Institute Groningen, Faculty of Science and Engineering, University of Groningen, Groningen, the Netherlands
| | - Simon Bergsma
- Products and Processes for Biotechnology, Engineering and Technology Institute Groningen, Faculty of Science and Engineering, University of Groningen, Groningen, the Netherlands
| | - Dana Irene Colpa
- Products and Processes for Biotechnology, Engineering and Technology Institute Groningen, Faculty of Science and Engineering, University of Groningen, Groningen, the Netherlands
| | - Gert-Jan Willem Euverink
- Products and Processes for Biotechnology, Engineering and Technology Institute Groningen, Faculty of Science and Engineering, University of Groningen, Groningen, the Netherlands
| | - Janneke Krooneman
- Products and Processes for Biotechnology, Engineering and Technology Institute Groningen, Faculty of Science and Engineering, University of Groningen, Groningen, the Netherlands; Bioconversion and Fermentation Technology, Research Centre Biobased Economy, Hanze University of Applied Sciences, Groningen, the Netherlands.
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2
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Lhamo P, Mahanty B. Structural Variability, Implementational Irregularities in Mathematical Modelling of Polyhydroxyalkanoates (PHAs) Production– a State of the Art Review. Biotechnol Bioeng 2022; 119:3079-3095. [DOI: 10.1002/bit.28213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/09/2022] [Accepted: 08/17/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Pema Lhamo
- Department of Biotechnology, Karunya Institute of Technology and SciencesCoimbatore641114Tamil NaduIndia
| | - Biswanath Mahanty
- Department of Biotechnology, Karunya Institute of Technology and SciencesCoimbatore641114Tamil NaduIndia
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3
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Miu DM, Eremia MC, Moscovici M. Polyhydroxyalkanoates (PHAs) as Biomaterials in Tissue Engineering: Production, Isolation, Characterization. MATERIALS 2022; 15:ma15041410. [PMID: 35207952 PMCID: PMC8875380 DOI: 10.3390/ma15041410] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/30/2022] [Accepted: 02/07/2022] [Indexed: 12/21/2022]
Abstract
Polyhydroxyalkanoates (PHAs) are biodegradable and biocompatible biopolymers. These biomaterials have grown in importance in the fields of tissue engineering and tissue reconstruction for structural applications where tissue morphology is critical, such as bone, cartilage, blood vessels, and skin, among others. Furthermore, they can be used to accelerate the regeneration in combination with drugs, as drug delivery systems, thus reducing microbial infections. When cells are cultured under stress conditions, a wide variety of microorganisms produce them as a store of intracellular energy in the form of homo- and copolymers of [R]—hydroxyalkanoic acids, depending on the carbon source used for microorganism growth. This paper gives an overview of PHAs, their biosynthetic pathways, producing microorganisms, cultivation bioprocess, isolation, purification and characterization to obtain biomaterials with medical applications such as tissue engineering.
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Affiliation(s)
- Dana-Maria Miu
- The National Institute for Chemical Pharmaceutical Research & Development, 031299 Bucharest, Romania; (D.-M.M.); (M.M.)
- Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 011061 Bucharest, Romania
| | - Mihaela Carmen Eremia
- The National Institute for Chemical Pharmaceutical Research & Development, 031299 Bucharest, Romania; (D.-M.M.); (M.M.)
- Correspondence:
| | - Misu Moscovici
- The National Institute for Chemical Pharmaceutical Research & Development, 031299 Bucharest, Romania; (D.-M.M.); (M.M.)
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Bosco F, Cirrincione S, Carletto R, Marmo L, Chiesa F, Mazzoli R, Pessione E. PHA Production from Cheese Whey and "Scotta": Comparison between a Consortium and a Pure Culture of Leuconostoc mesenteroides. Microorganisms 2021; 9:2426. [PMID: 34946028 PMCID: PMC8704080 DOI: 10.3390/microorganisms9122426] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 11/17/2021] [Indexed: 11/19/2022] Open
Abstract
It is urgent to expand the market of biodegradable alternatives to oil-derived plastics owing to (i) increasingly limited oil availability/accessibility, and (ii) the dramatic impact of traditional plastics on aquatic life, the food chain, all Earth ecosystems, and ultimately, human health. Polyhydroxyalkanoates (PHAs) are promising biodegradable polymers that can be obtained through microbial fermentation of agro-industrial byproducts, e.g., milk and cheese whey. Here, the PHA-accumulating efficiency of a mixed microbial culture (MMC, derived from activated sludges) grown on dairy byproducts (cheese and scotta whey) was measured. Bioreactor tests featuring temperature and pH control showed that both scotta and pre-treated Toma cheese whey could be used for PHA production by MMC, although scotta cheese whey supported higher PHA yield and productivity. The advantages of open MMCs include their plasticity and versatility to fast changing conditions; furthermore, no growth-medium sterilization is needed prior to fermentation. However, the use of pure cultures of efficient PHA producers may support better metabolic performances. Therefore, PHA-producing strains were isolated from a MMC, leading to the satisfactory identification of two bacterial strains, Citrobacter freundii and Leuconostoc spp., whose ability to accumulate PHAs in synthetic media was confirmed. A more detailed investigation by mass spectrometry revealed that the strain was L. mesenteroides. Although the validation of L. mesenteroides potential to produce PHA through fermentation of agro-industrial byproducts requires further investigations, this is the first study reporting PHA production with the Leuconostoc genus.
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Affiliation(s)
- Francesca Bosco
- Department of Applied Science and Technology, Politecnico di Torino, 10129 Turin, Italy;
| | - Simona Cirrincione
- Structural and Functional Biochemistry, Laboratory of Microbial Biochemistry and Proteomics, Department of Life Sciences and Systems Biology, Università di Torino, 10123 Torino, Italy; (S.C.); (R.M.); (E.P.)
| | - Riccardo Carletto
- CNR-STIIMA, Consiglio Nazionale delle Ricerche- Istituto di Sistemi e Tecnologie Industriali Intelligenti per il Manifatturiero Avanzato, 13900 Biella, Italy;
| | - Luca Marmo
- Department of Applied Science and Technology, Politecnico di Torino, 10129 Turin, Italy;
| | - Francesco Chiesa
- Department of Veterinary Science (DSV), Università degli Studi di Torino, 10095 Grugliasco, Italy;
| | - Roberto Mazzoli
- Structural and Functional Biochemistry, Laboratory of Microbial Biochemistry and Proteomics, Department of Life Sciences and Systems Biology, Università di Torino, 10123 Torino, Italy; (S.C.); (R.M.); (E.P.)
| | - Enrica Pessione
- Structural and Functional Biochemistry, Laboratory of Microbial Biochemistry and Proteomics, Department of Life Sciences and Systems Biology, Università di Torino, 10123 Torino, Italy; (S.C.); (R.M.); (E.P.)
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5
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Magdalena JA, González-Fernández C. Microalgae Biomass as a Potential Feedstock for the Carboxylate Platform. Molecules 2019; 24:molecules24234404. [PMID: 31810301 PMCID: PMC6930456 DOI: 10.3390/molecules24234404] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 11/26/2019] [Accepted: 11/30/2019] [Indexed: 11/16/2022] Open
Abstract
Volatile fatty acids (VFAs) are chemical building blocks for industries, and are mainly produced via the petrochemical pathway. However, the anaerobic fermentation (AF) process gives a potential alternative to produce these organic acids using renewable resources. For this purpose, waste streams, such as microalgae biomass, might constitute a cost-effective feedstock to obtain VFAs. The present review is intended to summarize the inherent potential of microalgae biomass for VFA production. Different strategies, such as the use of pretreatments to the inoculum and the manipulation of operational conditions (pH, temperature, organic loading rate or hydraulic retention time) to promote VFA production from different microalgae strains, are discussed. Microbial structure analysis using microalgae biomass as a substrate is pointed out in order to further comprehend the roles of bacteria and archaea in the AF process. Finally, VFA applications in different industry fields are reviewed.
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6
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Wang X, Jiang X, Wu F, Ma Y, Che X, Chen X, Liu P, Zhang W, Ma X, Chen G. Microbial Poly‐3‐Hydroxybutyrate (PHB) as a Feed Additive for Fishes and Piglets. Biotechnol J 2019; 14:e1900132. [PMID: 31119892 DOI: 10.1002/biot.201900132] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 05/13/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Xuan Wang
- School of Life Sciences, Tsinghua‐Peking Center for Life Sciences, Center for Synthetic and Systems BiologyTsinghua UniversityBeijing 100084 China
| | - Xiao‐Ran Jiang
- School of Life Sciences, Tsinghua‐Peking Center for Life Sciences, Center for Synthetic and Systems BiologyTsinghua UniversityBeijing 100084 China
| | - Fuqing Wu
- School of Life Sciences, Tsinghua‐Peking Center for Life Sciences, Center for Synthetic and Systems BiologyTsinghua UniversityBeijing 100084 China
- Center for Nano and Micro‐MechanicsTsinghua UniversityBeijing 100084 China
- MOE Key Lab for Industrial BiocatalysisTsinghua UniversityBeijing 100084 China
| | - Yiming Ma
- School of Life Sciences, Tsinghua‐Peking Center for Life Sciences, Center for Synthetic and Systems BiologyTsinghua UniversityBeijing 100084 China
- Center for Nano and Micro‐MechanicsTsinghua UniversityBeijing 100084 China
| | - Xuemei Che
- School of Life Sciences, Tsinghua‐Peking Center for Life Sciences, Center for Synthetic and Systems BiologyTsinghua UniversityBeijing 100084 China
- Center for Nano and Micro‐MechanicsTsinghua UniversityBeijing 100084 China
| | - Xiyue Chen
- State Key Laboratory of Animal NutritionChina Agricultural UniversityNo. 2 Yuanmingyuan West Road Beijing 100193 China
| | - Ping Liu
- State Key Laboratory of Animal NutritionChina Agricultural UniversityNo. 2 Yuanmingyuan West Road Beijing 100193 China
| | - Wenbing Zhang
- The Key Laboratory of Aquaculture Nutrition and Feeds, Ministry of Agriculture, The Key Laboratory of Mariculture (Ministry of Education)Ocean University of ChinaQingdao 266003 China
| | - Xi Ma
- State Key Laboratory of Animal NutritionChina Agricultural UniversityNo. 2 Yuanmingyuan West Road Beijing 100193 China
| | - Guo‐Qiang Chen
- School of Life Sciences, Tsinghua‐Peking Center for Life Sciences, Center for Synthetic and Systems BiologyTsinghua UniversityBeijing 100084 China
- Center for Nano and Micro‐MechanicsTsinghua UniversityBeijing 100084 China
- MOE Key Lab for Industrial BiocatalysisTsinghua UniversityBeijing 100084 China
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Van Hung N, Bossier P, Hong NTX, Ludeseve C, Garcia-Gonzalez L, Nevejan N, De Schryver P. Does Ralstonia eutropha, rich in poly-β hydroxybutyrate (PHB), protect blue mussel larvae against pathogenic vibrios? JOURNAL OF FISH DISEASES 2019; 42:777-787. [PMID: 30850999 DOI: 10.1111/jfd.12981] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/23/2019] [Accepted: 01/25/2019] [Indexed: 06/09/2023]
Abstract
The natural amorphous polymer poly-β-hydroxybutyrate (PHB-A: lyophilized Ralstonia eutropha containing 75% PHB) was used as a biological agent to control bacterial pathogens of blue mussel (Mytilus edulis) larvae. The larvae were supplied with PHB-A at a concentration of 1 or 10 mg/L for 6 or 24 hr, followed by exposure to either the rifampicin-resistant pathogen Vibrio splendidus or Vibrio coralliilyticus at a concentration of 105 CFU/ml. Larvae pretreated 6 hr with PHB-A (1 mg/L) survived a Vibrio challenge better relative to 24 hr pretreatment. After 96 hr of pathogen exposure, the survival of PHB-A-treated mussel larvae was 1.41- and 1.76-fold higher than the non-treated larvae when challenged with V. splendidus and V. coralliilyticus, respectively. Growth inhibition of the two pathogens at four concentrations of the monomer β-HB (1, 5, 25 and 125 mM) was tested in vitro in LB35 medium, buffered at two different pH values (pH 7 and pH 8). The highest concentration of 125 mM significantly inhibited the pathogen growth in comparison to the lower levels. The effect of β-HB on the production of virulence factors in the tested pathogenic Vibrios revealed a variable pattern of responses.
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Affiliation(s)
- Nguyen Van Hung
- Laboratory of Aquaculture & Artemia Reference Center, Ghent University, Ghent, Belgium
- Research Institute for Aquaculture No.3, Nhatrang, Vietnam
| | - Peter Bossier
- Laboratory of Aquaculture & Artemia Reference Center, Ghent University, Ghent, Belgium
| | - Nguyen Thi X Hong
- Laboratory of Aquaculture & Artemia Reference Center, Ghent University, Ghent, Belgium
| | - Christine Ludeseve
- Laboratory of Aquaculture & Artemia Reference Center, Ghent University, Ghent, Belgium
| | | | - Nancy Nevejan
- Laboratory of Aquaculture & Artemia Reference Center, Ghent University, Ghent, Belgium
| | - Peter De Schryver
- Laboratory of Aquaculture & Artemia Reference Center, Ghent University, Ghent, Belgium
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8
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John G, Nagarajan S, Vemula PK, Silverman JR, Pillai C. Natural monomers: A mine for functional and sustainable materials – Occurrence, chemical modification and polymerization. Prog Polym Sci 2019. [DOI: 10.1016/j.progpolymsci.2019.02.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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9
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Liao Q, Guo L, Ran Y, Gao M, She Z, Zhao Y, Liu Y. Optimization of polyhydroxyalkanoates (PHA) synthesis with heat pretreated waste sludge. WASTE MANAGEMENT (NEW YORK, N.Y.) 2018; 82:15-25. [PMID: 30509577 DOI: 10.1016/j.wasman.2018.10.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 09/03/2018] [Accepted: 10/11/2018] [Indexed: 06/09/2023]
Abstract
To reduce the cost of polyhydroxyalkanoates (PHA) production and disposal amount of waste sludge simultaneously, the feasibility of using different heat pretreated sludge (60 °C, 80 °C, 100 °C, 120 °C) as external carbon source to synthesize PHA was examined in this study. The maximal PHA accumulation (24.1% of the dry cell weight) was achieved with 60 °C pretreated waste sludge, with the utilization efficiency of COD, proteins, carbohydrate and VFAs were 74.3%, 82.3%,47.2%,81.4%, respectively. Both of VFAs and non VFAs organics could be used as carbon source for PHA synthesis. The results of kinetic parameter analysis showed that the highest PHA production rate (0.23 mg COD/mg X·h) and the PHA conversion rate (0.46 mg COD/mg COD) all occurred when using 60 °C pretreated waste sludge. In order to further investigate the utilization of sludge carbon source for PHA synthesis, the three-dimensional fluorescence excitation-emission matrix (EEM) spectroscopy with fluorescence regional integration (FRI) analysis were introduced.
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Affiliation(s)
- Qianru Liao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Liang Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China; Key Laboratory of Marine Environmental and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China.
| | - Yihe Ran
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Mengchun Gao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Zonglian She
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Yangguo Zhao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
| | - Yiping Liu
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China
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10
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The production of poly(3-hydroxybutyrate) by thermophilic Caldimonas manganoxidans from glycerol. JOURNAL OF POLYMER RESEARCH 2018. [DOI: 10.1007/s10965-018-1486-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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11
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Koller M, Vadlja D, Braunegg G, Atlić A, Horvat P. Formal- and high-structured kinetic process modelling and footprint area analysis of binary imaged cells: Tools to understand and optimize multistage-continuous PHA biosynthesis. EUROBIOTECH JOURNAL 2017. [DOI: 10.24190/issn2564-615x/2017/03.01] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Abstract
Competitive polyhydroxyalkanoate (PHAs) production requires progress in microbial strain performance, feedstock selection, downstream processing, and more importantly according to the process design with process kinetics of the microbial growth phase and the phase of product formation. The multistage continuous production in a bioreactor cascade was described for the first time in a continuously operated, flexible five-stage bioreactor cascade that mimics the characteristics involved in the engineering process of tubular plug flow reactors. This process was developed and used for Cupriavidus necator-mediated PHA production at high volumetric and specific PHA productivity (up to 2.31 g/(Lh) and 0.105 g/(gh), respectively). Based on the experimental data, formal kinetic and high structured kinetic models were established, accompanied by footprint area analysis of binary imaged cells. As a result of the study, there has been an enhanced understanding of the long-term continuous PHA production under balanced, transient, and nutrient-deficient conditions that was achieved on both the micro and the macro kinetic level. It can also be concluded that there were novel insights into the complex metabolic occurrences that developed during the multistage- continuous production of PHA as a secondary metabolite. This development was essential in paving the way for further process improvement. At the same time, a new method of specific growth rate and specific production rate based on footprint area analysis was established by using the electron microscope.
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Affiliation(s)
- Martin Koller
- University of Graz, Office of Research Management and Service, c/o Institute of Chemistry, NAWI Graz , Austria
- ARENA (Association for Resource Efficient and Sustainable Technologies), Graz , Austria
| | - Denis Vadlja
- University of Zagreb, Faculty of Food Technology and Biotechnology, Department of Biochemical Engineering, Zagreb , Croatia
| | - Gerhart Braunegg
- ARENA (Association for Resource Efficient and Sustainable Technologies), Graz , Austria
| | - Aid Atlić
- VTU Technology GmbH, Grambach/ Graz , Austria
| | - Predrag Horvat
- University of Zagreb, Faculty of Food Technology and Biotechnology, Department of Biochemical Engineering, Zagreb , Croatia
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N Lyubenova V, N Ignatova M. On-line estimation of physiological states for monitoring and control of bioprocesses. AIMS BIOENGINEERING 2017. [DOI: 10.3934/bioeng.2017.1.93] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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14
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Perez-Garcia O, Lear G, Singhal N. Metabolic Network Modeling of Microbial Interactions in Natural and Engineered Environmental Systems. Front Microbiol 2016; 7:673. [PMID: 27242701 PMCID: PMC4870247 DOI: 10.3389/fmicb.2016.00673] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 04/25/2016] [Indexed: 12/14/2022] Open
Abstract
We review approaches to characterize metabolic interactions within microbial communities using Stoichiometric Metabolic Network (SMN) models for applications in environmental and industrial biotechnology. SMN models are computational tools used to evaluate the metabolic engineering potential of various organisms. They have successfully been applied to design and optimize the microbial production of antibiotics, alcohols and amino acids by single strains. To date however, such models have been rarely applied to analyze and control the metabolism of more complex microbial communities. This is largely attributed to the diversity of microbial community functions, metabolisms, and interactions. Here, we firstly review different types of microbial interaction and describe their relevance for natural and engineered environmental processes. Next, we provide a general description of the essential methods of the SMN modeling workflow including the steps of network reconstruction, simulation through Flux Balance Analysis (FBA), experimental data gathering, and model calibration. Then we broadly describe and compare four approaches to model microbial interactions using metabolic networks, i.e., (i) lumped networks, (ii) compartment per guild networks, (iii) bi-level optimization simulations, and (iv) dynamic-SMN methods. These approaches can be used to integrate and analyze diverse microbial physiology, ecology and molecular community data. All of them (except the lumped approach) are suitable for incorporating species abundance data but so far they have been used only to model simple communities of two to eight different species. Interactions based on substrate exchange and competition can be directly modeled using the above approaches. However, interactions based on metabolic feedbacks, such as product inhibition and synthropy require extensions to current models, incorporating gene regulation and compounding accumulation mechanisms. SMN models of microbial interactions can be used to analyze complex “omics” data and to infer and optimize metabolic processes. Thereby, SMN models are suitable to capitalize on advances in high-throughput molecular and metabolic data generation. SMN models are starting to be applied to describe microbial interactions during wastewater treatment, in-situ bioremediation, microalgae blooms methanogenic fermentation, and bioplastic production. Despite their current challenges, we envisage that SMN models have future potential for the design and development of novel growth media, biochemical pathways and synthetic microbial associations.
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Affiliation(s)
- Octavio Perez-Garcia
- Department of Civil and Environmental Engineering, University of Auckland Auckland, New Zealand
| | - Gavin Lear
- School of Biological Sciences, The University of Auckland Auckland, New Zealand
| | - Naresh Singhal
- Department of Civil and Environmental Engineering, University of Auckland Auckland, New Zealand
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15
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Mazzoli R, Bosco F, Mizrahi I, Bayer EA, Pessione E. Towards lactic acid bacteria-based biorefineries. Biotechnol Adv 2014; 32:1216-1236. [PMID: 25087936 DOI: 10.1016/j.biotechadv.2014.07.005] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 07/14/2014] [Accepted: 07/16/2014] [Indexed: 10/25/2022]
Abstract
Lactic acid bacteria (LAB) have long been used in industrial applications mainly as starters for food fermentation or as biocontrol agents or as probiotics. However, LAB possess several characteristics that render them among the most promising candidates for use in future biorefineries in converting plant-derived biomass-either from dedicated crops or from municipal/industrial solid wastes-into biofuels and high value-added products. Lactic acid, their main fermentation product, is an attractive building block extensively used by the chemical industry, owing to the potential for production of polylactides as biodegradable and biocompatible plastic alternative to polymers derived from petrochemicals. LA is but one of many high-value compounds which can be produced by LAB fermentation, which also include biofuels such as ethanol and butanol, biodegradable plastic polymers, exopolysaccharides, antimicrobial agents, health-promoting substances and nutraceuticals. Furthermore, several LAB strains have ascertained probiotic properties, and their biomass can be considered a high-value product. The present contribution aims to provide an extensive overview of the main industrial applications of LAB and future perspectives concerning their utilization in biorefineries. Strategies will be described in detail for developing LAB strains with broader substrate metabolic capacity for fermentation of cheaper biomass.
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Affiliation(s)
- Roberto Mazzoli
- Laboratory of Biochemistry: Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Torino, Via Accademia Albertina 13, 10123 Torino, Italy.
| | - Francesca Bosco
- Department of Applied Science and Technology (DISAT), Politecnico of Torino, Corso Duca degli Abruzzi, 24, 10129 Torino, Italy.
| | - Itzhak Mizrahi
- Institute of Animal Science, ARO, Volcani Research Center, P.O. Box 6Â, Bet Dagan 50-250, Israel.
| | - Edward A Bayer
- Department of Biological Chemistry, the Weizmann Institute of Science, Rehovot 76100 Israel.
| | - Enrica Pessione
- Laboratory of Biochemistry: Proteomics and Metabolic Engineering of Prokaryotes, Department of Life Sciences and Systems Biology, University of Torino, Via Accademia Albertina 13, 10123 Torino, Italy.
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16
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Lyubenova V, Ignatova M, Novak M, Patarinska T. Reaction Rate Estimators of Fed-Batch Process for Poly-β-Hydroxybutyrate (PHB) Production by Mixed Culture. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.1080/13102818.2007.10817426] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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17
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Mozumder MSI, Goormachtigh L, Garcia-Gonzalez L, De Wever H, Volcke EIP. Modeling pure culture heterotrophic production of polyhydroxybutyrate (PHB). BIORESOURCE TECHNOLOGY 2014; 155:272-280. [PMID: 24457311 DOI: 10.1016/j.biortech.2013.12.103] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 12/19/2013] [Accepted: 12/22/2013] [Indexed: 06/03/2023]
Abstract
In this contribution a mechanistic model describing the production of polyhydroxybutyrate (PHB) through pure-culture fermentation was developed, calibrated and validated for two different substrates, namely glucose and waste glycerol. In both cases, non-growth-associated PHB production was triggered by applying nitrogen limitation. The occurrence of some growth-associated PHB production besides non-growth-associated PHB production was demonstrated, although it is inhibited in the presence of nitrogen. Other phenomena observed experimentally and described by the model included biomass growth on PHB and non-linear product inhibition of PHB production. The accumulated impurities from the waste substrate negatively affected the obtained maximum PHB content. Overall, the developed mathematical model provided an accurate prediction of the dynamic behavior of heterotrophic biomass growth and PHB production in a two-phase pure culture system.
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Affiliation(s)
- Md Salatul Islam Mozumder
- Flemish Institute for Technological Research (VITO), Business Unit Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium; Ghent University, Department of Biosystems Engineering, Coupure Links 653, 9000 Gent, Belgium.
| | - Laurens Goormachtigh
- Ghent University, Department of Biosystems Engineering, Coupure Links 653, 9000 Gent, Belgium
| | - Linsey Garcia-Gonzalez
- Flemish Institute for Technological Research (VITO), Business Unit Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium
| | - Heleen De Wever
- Flemish Institute for Technological Research (VITO), Business Unit Separation and Conversion Technology, Boeretang 200, 2400 Mol, Belgium
| | - Eveline I P Volcke
- Ghent University, Department of Biosystems Engineering, Coupure Links 653, 9000 Gent, Belgium
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Vijayendra SVN, Shamala TR. Film forming microbial biopolymers for commercial applications—A review. Crit Rev Biotechnol 2013; 34:338-57. [DOI: 10.3109/07388551.2013.798254] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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19
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Microbial production of poly(hydroxybutyrate) from C₁ carbon sources. Appl Microbiol Biotechnol 2013; 97:1407-24. [PMID: 23306640 DOI: 10.1007/s00253-012-4649-0] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Revised: 12/08/2012] [Accepted: 12/10/2012] [Indexed: 02/01/2023]
Abstract
Polyhydroxybutyrate (PHB) is an attractive substitute for petrochemical plastic due to its similar properties, biocompatibility, and biodegradability. The cost of scaled-up PHB production inhibits its widespread usage. Intensive researches are growing to reduce costs and improve thermomechanical, physical, and processing properties of this green biopolymer. Among cheap substrates which are used for reducing total cost of PHB production, some C₁ carbon sources, e.g., methane, methanol, and CO₂ have received a great deal of attention due to their serious role in greenhouse problem. This article reviews the fundamentals of strategies for reducing PHA production and moves on to the applications of several cheap substrates with a special emphasis on methane, methanol, and CO₂. Also, some explanation for involved microorganisms including the hydrogen-oxidizing bacteria and methanotrophs, their history, culture condition, and nutritional requirements are given. After description of some important strains among the hydrogen-oxidizing and methanotrophic producers of PHB, the article is focused on limitations, threats, and opportunities for application and their future trends.
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Najdegerami EH, Tran TN, Defoirdt T, Marzorati M, Sorgeloos P, Boon N, Bossier P. Effects of poly-β-hydroxybutyrate (PHB) on Siberian sturgeon (Acipenser baerii) fingerlings performance and its gastrointestinal tract microbial community. FEMS Microbiol Ecol 2012; 79:25-33. [PMID: 22066757 DOI: 10.1111/j.1574-6941.2011.01194.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Poly-β-hydroxybutyrate (PHB) is a natural polymer that can be depolymerized into water-soluble short-chain fatty acid monomers. These monomers can act as microbial control agents. In this study, the effects of partially replacing the diet of Siberian sturgeon fingerlings with 2% and 5% PHB were investigated. Replacing 2% of the diet with PHB improved weight gain, specific growth rate (SGR) and survival in the sturgeon fingerlings during the 10-week experimental period. Community-level physiological profiling and PCR-denaturing gradient gel electrophoresis (PCR-DGGE) were used to analyze the microbial community diversity and community organization in the sturgeon gastrointestinal tract. DGGE analysis revealed that PHB affected the intestinal microbial species richness and diversity. The highest species richness was observed with 2% PHB. DNA sequencing of the dominant bands in 2% and 5% PHB treatments revealed that PHB stimulated bacteria belonging to the genera Bacillus and Ruminococcaceae. Principal component analysis, Lorenz curves and the Shannon index of Biolog Ecoplate data revealed that aerobic metabolic potential of the bacterial community was different in the PHB-treated fishes as compared with the control situation. Overall, our results indicate that PHB act as microbial control agents and replacement of 2% of Siberian sturgeon fingerling diet with PHB has beneficial effects.
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Affiliation(s)
- Ebrahim H Najdegerami
- Laboratory of Aquaculture & Artemia Reference Center, Ghent University, Ghent, Belgium.
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Pillai CKS. Challenges for Natural Monomers and Polymers: Novel Design Strategies and Engineering to Develop Advanced Polymers. Des Monomers Polym 2012. [DOI: 10.1163/138577210x12634696333190] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- C. K. S. Pillai
- a Chemical Sciences and Technology Division, Regional Research Laboratory (Now NIIST), Thiruvanananthapuram-695 019, India
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22
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Wendlandt KD, Stottmeister U, Helm J, Soltmann B, Jechorek M, Beck M. The potential of methane-oxidizing bacteria for applications in environmental biotechnology. Eng Life Sci 2010. [DOI: 10.1002/elsc.200900093] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Bader J, Mast-Gerlach E, Popović MK, Bajpai R, Stahl U. Relevance of microbial coculture fermentations in biotechnology. J Appl Microbiol 2009; 109:371-387. [PMID: 20070440 DOI: 10.1111/j.1365-2672.2009.04659.x] [Citation(s) in RCA: 186] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The purpose of this article is to review coculture fermentations in industrial biotechnology. Examples for the advantageous utilization of cocultures instead of single cultivations include the production of bulk chemicals, enzymes, food additives, antimicrobial substances and microbial fuel cells. Coculture fermentations may result in increased yield, improved control of product qualities and the possibility of utilizing cheaper substrates. Cocultivation of different micro-organisms may also help to identify and develop new biotechnological substances. The relevance of coculture fermentations and the potential of improving existing processes as well as the production of new chemical compounds in industrial biotechnology are pointed out here by means of more than 35 examples.
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Affiliation(s)
- J Bader
- Technische Universität Berlin, Fachgebiet Mikrobiologie and Genetik, Seestraβe 13, Berlin, Germany
| | - E Mast-Gerlach
- Technische Universität Berlin, Fachgebiet Mikrobiologie and Genetik, Seestraβe 13, Berlin, Germany
| | - M K Popović
- Beuth Hochschule für Technik, Fachbereich Biotechnologie, Seestraβe 64, Berlin, Germany
| | - R Bajpai
- Chemical Engineering Department, University of Louisiana at Lafayette, Lafayette, LA, USA
| | - U Stahl
- Technische Universität Berlin, Fachgebiet Mikrobiologie and Genetik, Seestraβe 13, Berlin, Germany
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Short-chain fatty acids and poly-beta-hydroxyalkanoates: (New) Biocontrol agents for a sustainable animal production. Biotechnol Adv 2009; 27:680-685. [PMID: 19422908 DOI: 10.1016/j.biotechadv.2009.04.026] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 04/27/2009] [Accepted: 04/28/2009] [Indexed: 01/18/2023]
Abstract
Because of the risk of antibiotic resistance development, there is a growing awareness that antibiotics should be used more carefully in animal production. However, a decreased use of antibiotics could result in a higher frequency of pathogenic bacteria, which in its turn could lead to a higher incidence of infections. Short-chain fatty acids (SCFAs) have long been known to exhibit bacteriostatic activity. These compounds also specifically downregulate virulence factor expression and positively influence the gastrointestinal health of the host. As a consequence, there is currently considerable interest in SCFAs as biocontrol agents in animal production. Polyhydroxyalkanoates (PHAs) are polymers of beta-hydroxy short-chain fatty acids. Currently, PHAs are applied as replacements for synthetic polymers. These biopolymers can be depolymerised by many different microorganisms that produce extracellular PHA depolymerases. Interestingly, different studies provided some evidence that PHAs can also be degraded upon passage through the gastrointestinal tract of animals and consequently, adding these compounds to the feed might result in biocontrol effects similar to those described for SCFAs.
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Mengmeng C, Hong C, Qingliang Z, Shirley SN, Jie R. Optimal production of polyhydroxyalkanoates (PHA) in activated sludge fed by volatile fatty acids (VFAs) generated from alkaline excess sludge fermentation. BIORESOURCE TECHNOLOGY 2009; 100:1399-405. [PMID: 18945612 DOI: 10.1016/j.biortech.2008.09.014] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 09/04/2008] [Accepted: 09/04/2008] [Indexed: 05/20/2023]
Abstract
To reduce the production cost of polyhydroxyalkanoates (PHA) and disposal amount of excess sludge simultaneously, the feasibility of using fermentative volatile fatty acids (VFAs) as carbon sources to synthesize PHA by activated sludge was examined. At pH 11.0, 60 degrees C and fermentative time of 7d, the VFAs yield was 258.65 mgTOC/gVSS. To restrain cell growth during PHA production, the released phosphorus and residual ammonium in the fermentative VFAs was recovered by the formation of struvite precipitation. Acetic acid was the predominant composition of the fermentative VFAs. PHA accumulation in excess sludge occurred feeding by fermentative VFAs with aerobic dynamic feeding process. The maximum PHA content accounted for 56.5% of the dry cell. It can be concluded from this study that the VFAs generated from excess sludge fermentation were a suitable carbon source for PHA production by activated sludge.
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Affiliation(s)
- Cai Mengmeng
- School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, China.
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Patnaik PR. Cognitive optimization of microbial PHB production in an optimally dispersed bioreactor by single and mixed cultures. Bioprocess Biosyst Eng 2008; 32:557-68. [DOI: 10.1007/s00449-008-0277-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Accepted: 10/27/2008] [Indexed: 12/21/2022]
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Patnaik PR. Design Considerations in Hybrid Neural Optimization of Fed-Batch Fermentation for PHB Production by Ralstonia eutropha. FOOD BIOPROCESS TECH 2008. [DOI: 10.1007/s11947-008-0086-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Vijayendra SVN, Rastogi NK, Shamala TR, Anil Kumar PK, Kshama L, Joshi GJ. Optimization of polyhydroxybutyrate production by Bacillus sp. CFR 256 with corn steep liquor as a nitrogen source. Indian J Microbiol 2007; 47:170-5. [PMID: 23100662 PMCID: PMC3450111 DOI: 10.1007/s12088-007-0033-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Revised: 03/29/2007] [Accepted: 03/30/2007] [Indexed: 11/26/2022] Open
Abstract
Polyhydroxyalkanotes (PHAs), the eco-friendly biopolymers produced by many bacteria, are gaining importance in curtailing the environmental pollution by replacing the non-biodegradable plastics derived from petroleum. The present study was carried out to economize the polyhydroxybutyrate (PHB) production by optimizing the fermentation medium using corn steep liquor (CSL), a by-product of starch processing industry, as a cheap nitrogen source, by Bacillus sp. CFR 256. Response surface methodology (RSM) was used to optimize the fermentation medium using the variables such as corn steep liquor (5-25 g l(-1)), Na(2)HPO(4) 2H(2)O (2.2-6.2 g l(-1)), KH(2)PO(4) (0.5-2.5 g l(-1)), sucrose (5-55 g l(-1)) and inoculum concentration (1-25 ml l(-1)). Central composite rotatable design (CCRD) experiments were carried out to study the complex interactions of the variables.The optimum conditions for maximum PHB production were (g l(-1)): CSL-25, Na(2)HPO(4) 2H(2)O-2.2, KH(2)PO(4) - 0.5, sucrose - 55 and inoculum - 10 (ml l(-1)). After 72 h of fermentation, the amount of PHA produced was 8.20 g l(-1) (51.20% of dry cell biomass). It is the first report on optimization of fermentation medium using CSL as a nitrogen source, for PHB production by Bacillus sp.
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Affiliation(s)
- S. V. N. Vijayendra
- Department of Food Microbiology, Central Food Technological Research Institute, Mysore, 570 020 India
| | - N. K. Rastogi
- Department of Food Engineering, Central Food Technological Research Institute, Mysore, 570 020 India
| | - T. R. Shamala
- Department of Food Microbiology, Central Food Technological Research Institute, Mysore, 570 020 India
| | - P. K. Anil Kumar
- Department of Food Microbiology, Central Food Technological Research Institute, Mysore, 570 020 India
| | - L. Kshama
- Department of Food Microbiology, Central Food Technological Research Institute, Mysore, 570 020 India
| | - G. J. Joshi
- Department of Food Microbiology, Central Food Technological Research Institute, Mysore, 570 020 India
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Verlinden RAJ, Hill DJ, Kenward MA, Williams CD, Radecka I. Bacterial synthesis of biodegradable polyhydroxyalkanoates. J Appl Microbiol 2007; 102:1437-49. [PMID: 17578408 DOI: 10.1111/j.1365-2672.2007.03335.x] [Citation(s) in RCA: 368] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Various bacterial species accumulate intracellular polyhydroxyalkanoates (PHAs) granules as energy and carbon reserves inside their cells. PHAs are biodegradable, environmentally friendly and biocompatible thermoplastics. Varying in toughness and flexibility, depending on their formulation, they can be used in various ways similar to many nonbiodegradable petrochemical plastics currently in use. They can be used either in pure form or as additives to oil-derived plastics such as polyethylene. However, these bioplastics are currently far more expensive than petrochemically based plastics and are therefore used mostly in applications that conventional plastics cannot perform, such as medical applications. PHAs are immunologically inert and are only slowly degraded in human tissue, which means they can be used as devices inside the body. Recent research has focused on the use of alternative substrates, novel extraction methods, genetically enhanced species and mixed cultures with a view to make PHAs more commercially attractive.
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Affiliation(s)
- R A J Verlinden
- School of Applied Sciences, University of Wolverhampton, Wolverhampton, UK
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Patnaik PR. ANALYSIS OF THE EFFECT OF FLOW INTERRUPTIONS ON FED-BATCH FERMENTATION FOR PHB PRODUCTION BYRALSTONIA EUTROPHAIN FINITELY DISPERSED BIOREACTORS. CHEM ENG COMMUN 2007. [DOI: 10.1080/00986440600992677] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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32
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Keenan TM, Nakas JP, Tanenbaum SW. Polyhydroxyalkanoate copolymers from forest biomass. J Ind Microbiol Biotechnol 2006; 33:616-26. [PMID: 16761168 DOI: 10.1007/s10295-006-0131-2] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Accepted: 04/04/2006] [Indexed: 11/24/2022]
Abstract
The potential for the use of woody biomass in poly-beta-hydroxyalkanoate (PHA) biosynthesis is reviewed. Based on previously cited work indicating incorporation of xylose or levulinic acid (LA) into PHAs by several bacterial strains, we have initiated a study for exploring bioconversion of forest resources to technically relevant copolymers. Initially, PHA was synthesized in shake-flask cultures of Burkholderia cepacia grown on 2.2% (w/v) xylose, periodically amended with varying concentrations of levulinic acid [0.07-0.67% (w/v)]. Yields of poly(beta-hydroxybutyrate-co-beta-hydroxyvalerate) [P(3HB-co-3HV)] from 1.3 to 4.2 g/l were obtained and could be modulated to contain from 1.0 to 61 mol% 3-hydroxyvalerate (3HV), as determined by 1H and 13C NMR analyses. No evidence for either the 3HB or 4HV monomers was found. Characterization of these P(3HB-co-3HV) samples, which ranged in molecular mass (viscometric, Mv) from 511-919 kDa, by differential scanning calorimetry and thermogravimetric analyses (TGA) provided data which were in agreement for previously reported P(3HB-co-3HV) copolymers. For these samples, it was noted that melting temperature (Tm) and glass transition temperature (Tg) decreased as a function of 3HVcontent, with Tm demonstrating a pseudoeutectic profile as a function of mol% 3HV content. In order to extend these findings to the use of hemicellulosic process streams as an inexpensive carbon source, a detoxification procedure involving sequential overliming and activated charcoal treatments was developed. Two such detoxified process hydrolysates (NREL CF: aspen and CESF: maple) were each fermented with appropriate LA supplementation. For the NREL CF hydrolysate-based cultures amended with 0.25-0.5% LA, P(3HB-co-3HV) yields, PHA contents (PHA as percent of dry biomass), and mol% 3HV compositions of 2.0 g/l, 40% (w/w), and 16-52 mol% were obtained, respectively. Similarly, the CESF hydrolysate-based shake-flask cultures yielded 1.6 g/l PHA, 39% (w/w) PHA contents, and 4-67 mol% 3HV compositions. These data are comparable to copolymer yields and cellular contents reported for hexose plus levulinic acid-based shake-flask cultures, as reported using Alcaligenes eutrophus and Pseudomonas putida. However, our findings presage a conceivable alternative, forestry-based biorefinery approach for the production of value-added biodegradable PHA polymers. Specifically, this review describes the current and potential utilization of lignocellulosic process streams as platform precursors to PHA polymers including hemicellulosic hydrolysates, residual cellulose-derived levulinic acid, tall oil fatty acids (Kraft pulping residual), and lignin-derived aromatics.
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Affiliation(s)
- Thomas M Keenan
- Department of Environmental and Forest Biology, State University of New York, College of Environmental Science and Forestry (SUNY-ESF), Syracuse, NY 13210, USA
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