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Goswami L, Kushwaha A, Napathorn SC, Kim BS. Valorization of organic wastes using bioreactors for polyhydroxyalkanoate production: Recent advancement, sustainable approaches, challenges, and future perspectives. Int J Biol Macromol 2023; 247:125743. [PMID: 37423435 DOI: 10.1016/j.ijbiomac.2023.125743] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Revised: 06/23/2023] [Accepted: 07/06/2023] [Indexed: 07/11/2023]
Abstract
Microbial polyhydroxyalkanoates (PHA) are encouraging biodegradable polymers, which may ease the environmental problems caused by petroleum-derived plastics. However, there is a growing waste removal problem and the high price of pure feedstocks for PHA biosynthesis. This has directed to the forthcoming requirement to upgrade waste streams from various industries as feedstocks for PHA production. This review covers the state-of-the-art progress in utilizing low-cost carbon substrates, effective upstream and downstream processes, and waste stream recycling to sustain entire process circularity. This review also enlightens the use of various batch, fed-batch, continuous, and semi-continuous bioreactor systems with flexible results to enhance the productivity and simultaneously cost reduction. The life-cycle and techno-economic analyses, advanced tools and strategies for microbial PHA biosynthesis, and numerous factors affecting PHA commercialization were also covered. The review includes the ongoing and upcoming strategies viz. metabolic engineering, synthetic biology, morphology engineering, and automation to expand PHA diversity, diminish production costs, and improve PHA production with an objective of "zero-waste" and "circular bioeconomy" for a sustainable future.
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Affiliation(s)
- Lalit Goswami
- Department of Chemical Engineering, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea
| | - Anamika Kushwaha
- Department of Chemical Engineering, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea
| | | | - Beom Soo Kim
- Department of Chemical Engineering, Chungbuk National University, Cheongju, Chungbuk 28644, Republic of Korea.
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Abdelmalek F, Steinbüchel A, Rofeal M. The Hyperproduction of Polyhydroxybutyrate Using Bacillus mycoides ICRI89 through Enzymatic Hydrolysis of Affordable Cardboard. Polymers (Basel) 2022; 14:polym14142810. [PMID: 35890586 PMCID: PMC9322056 DOI: 10.3390/polym14142810] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/06/2022] [Accepted: 07/08/2022] [Indexed: 12/14/2022] Open
Abstract
Bioplastics are contemplated as remarkable substitutes for conventional plastics to accommodate green technological advancements. However, their industrial production has not been fully implemented owing to the cost of carbon resources. From another perspective, valorizing different paper mill wastes has become a prominent research topic. These materials may serve as an affording sustainable feedstock for bioplastic production. Adjustment of cardboard waste hydrolysate as suitable fermentation media for production of bacterial polyhydroxyalkanoates (PHAs) has been investigated. Cardboard samples were defibered and dried before enzymatic hydrolysis. The enzymatic degradation of commercial cellulase was monitored over 15 days. Interestingly, 18.2 ± 0.2 g/L glucose yield was obtained from 50 g cardboard samples using a 1.5% (v/v) enzyme concentration. The samples exhibited maximum weight loss values of 69-73%. Meanwhile, five soil samples were collected from local sites in Lodz, Poland. A total of 31 bacterial isolates were screened and cultured on Nile blue plates. Analysis of the 16S rRNA gene sequence of the most potent producer revealed 100% similarity to Bacillus mycoides. Cardboard hydrolysates whole medium, modified MSM with cardboard hydrolysate and nitrogen depleted MSM with cardboard hydrolysate were utilized for PHA production, followed by PHA productivity and cell dry weight (CDW) estimation compared to glucose as a standard carbon source. An impressive PHA accumulation of 56% CDW was attained when the waste hydrolysate was used as a carbon source. FTIR and NMR analysis of the isolated PHA indicated that functional groups of the polymer were related to PHB (polyhydroxybutyrate). Thermal analysis demonstrates that PHB and PHB-CB (PHB produced from cardboard hydrolysate) have degradation temperatures of 380 and 369 °C, respectively, which reflect the high thermal stability and heat resistance compared to the same properties for a standard polymer. This is the first demonstration of full saccharification of corrugated cardboard paper waste for high-level production of PHA. In addition, the attained PHB productivity is one of the highest levels achieved from a real lignocellulosic waste.
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Affiliation(s)
- Fady Abdelmalek
- International Center for Research on Innovative Biobased Materials (ICRI-BioM)-International Research Agenda, Lodz University of Technology, Zeromskiego 116, 90-924 Lodz, Poland; (F.A.); (A.S.)
| | - Alexander Steinbüchel
- International Center for Research on Innovative Biobased Materials (ICRI-BioM)-International Research Agenda, Lodz University of Technology, Zeromskiego 116, 90-924 Lodz, Poland; (F.A.); (A.S.)
| | - Marian Rofeal
- International Center for Research on Innovative Biobased Materials (ICRI-BioM)-International Research Agenda, Lodz University of Technology, Zeromskiego 116, 90-924 Lodz, Poland; (F.A.); (A.S.)
- Department of Botany and Microbiology, Faculty of Science, Alexandria University, Moharam Bek, Alexandria 21521, Egypt
- Correspondence:
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Kataki S, Nityanand K, Chatterjee S, Dwivedi SK, Kamboj DV. Plastic waste management practices pertaining to India with particular focus on emerging technologies. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:24478-24503. [PMID: 35064479 DOI: 10.1007/s11356-021-17974-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 12/02/2021] [Indexed: 06/14/2023]
Abstract
Under the parent petrochemical industries, plastic industry is proliferating enormously over the past several years globally due to its advantages in terms of weight, robustness, expense, versatility, and durability. Due to the diversified consumer base representing varied climate zones, food habits, and standards of living, the generation and growth opportunities for the plastic industry in India are particularly distinct and humongous. The present work extensively reviews the Indian plastic industry with primary focus on the evolving technologies for plastic waste valorization encompassing their level of utilization, technology readiness, and progress achieved at R&D level. The study attempts to recognize different issues related to technology, recycling, policy, research, regulation that should be given attention to formulate an improved plastic waste management strategy in the region. Though significant shares of waste plastics in the country are processed by traditional practices, state-of-the-art technologies primarily plastic to oil conversion, in road making and in cement manufacturing, are being deployed at increasing rate. Action to tackle the problem of plastic contamination in India will need to adopt a pan India strategic consensus/concurrent approach for effective waste collection and segregation with active participation of urban local bodies, fixing the role of the informal sectors, investment for reliable technology adoption with skilled manpower for operation, adoption of circular economy schemes involving plastic waste co-processing, and providing support to work on R&D for better penetration of the proven plastic valorization options along with their environmental and social implications.
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Affiliation(s)
- Sampriti Kataki
- Biodegradation Technology Division, Defence Research Laboratory, DRDO, Tezpur, 784001, Assam, India
| | - Krithika Nityanand
- Biodegradation Technology Division, Defence Research Laboratory, DRDO, Tezpur, 784001, Assam, India
- Delhi Technological University, Shahbad, Daulatpur, Delhi, 110042, India
| | - Soumya Chatterjee
- Biodegradation Technology Division, Defence Research Laboratory, DRDO, Tezpur, 784001, Assam, India.
| | - Sanjai K Dwivedi
- Biodegradation Technology Division, Defence Research Laboratory, DRDO, Tezpur, 784001, Assam, India
| | - Dev Vrat Kamboj
- Biodegradation Technology Division, Defence Research Laboratory, DRDO, Tezpur, 784001, Assam, India
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Haloarchaea as emerging big players in future polyhydroxyalkanoate bioproduction: Review of trends and perspectives. CURRENT RESEARCH IN BIOTECHNOLOGY 2022. [DOI: 10.1016/j.crbiot.2022.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Ghosh S, Coons J, Yeager C, Halley P, Chemodanov A, Belgorodsky B, Gozin M, Chen GQ, Golberg A. Halophyte biorefinery for polyhydroxyalkanoates production from Ulva sp. Hydrolysate with Haloferax mediterranei in pneumatically agitated bioreactors and ultrasound harvesting. BIORESOURCE TECHNOLOGY 2022; 344:125964. [PMID: 34728090 DOI: 10.1016/j.biortech.2021.125964] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
The present study tested the outdoor cultivation of Haloferax mediterranei for PHA production from green macroalgae Ulva sp. in pneumatically agitated bioreactors and applied ultrasonic separation for enhanced settling of archaeal cells. Scaled-up cultivation (40 L) yielded maximum biomass productivity of 50.1 ± 0.11 mg·L-1·h-1 with a PHA productivity of 27 ± 0.01 mg·L-1·h-1 and conversion yield of 0.107 g PHA per gram UlvaDW. The maximum mass fraction of PHA achieved in biomass was calculated to be 56% w/w. Ultrasonic harvesting of Hfx. mediterranei cells approached 30% removal at energy inputs around 7.8 kWh·m-3, and indicated no significant aggregation enhancement by Ca2+ addition. Molecular weight analysis showed an increase in Polydispersity Index (PDI) when the corresponding air velocities were increased suggesting that the polymer was more homogeneous at lower mixing velocities. The current study demonstrated scalable processes for PHA production using Ulva sp. feedstock providing new technologies for halophilic biorefinery.
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Affiliation(s)
- Supratim Ghosh
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel.
| | - Jim Coons
- Chemical Diagnostics and Engineering Group, Chemistry Division, Los Alamos National Laboratory, MS J964, Bikini Atoll Rd, Los Alamos, NM 87545 USA
| | - Chris Yeager
- Chemical Diagnostics and Engineering Group, Chemistry Division, Los Alamos National Laboratory, MS J964, Bikini Atoll Rd, Los Alamos, NM 87545 USA
| | - Peter Halley
- School of Chemical Engineering, University of Queensland, St Lucia QLD 4072 Australia
| | - Alexander Chemodanov
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Bogdan Belgorodsky
- School of Chemistry, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Michael Gozin
- School of Chemistry, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Guo-Qiang Chen
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, PR China
| | - Alexander Golberg
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
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Obruča S, Dvořák P, Sedláček P, Koller M, Sedlář K, Pernicová I, Šafránek D. Polyhydroxyalkanoates synthesis by halophiles and thermophiles: towards sustainable production of microbial bioplastics. Biotechnol Adv 2022; 58:107906. [DOI: 10.1016/j.biotechadv.2022.107906] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 12/15/2021] [Accepted: 01/07/2022] [Indexed: 01/10/2023]
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de la Haba RR, Minegishi H, Kamekura M, Shimane Y, Ventosa A. Phylogenomics of Haloarchaea: The Controversy of the Genera Natrinema-Haloterrigena. Front Microbiol 2021; 12:740909. [PMID: 34690986 PMCID: PMC8530250 DOI: 10.3389/fmicb.2021.740909] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 08/25/2021] [Indexed: 02/03/2023] Open
Abstract
The haloarchaeal genera Natrinema and Haloterrigena were described almost simultaneously by two different research groups and some strains studied separately were described as different species of these genera. Furthermore, the description of additional species were assigned to either Natrinema or Haloterrigena, mainly on the basis of the phylogenetic comparative analysis of single genes (16S rRNA gene and more recently rpoB’ gene), but these species were not adequately separated or assigned to the corresponding genus. Some studies suggested that the species of these two genera should be unified into a single genus, while other studies indicated that the genera should remain but some of the species should be reassigned. In this study, we have sequenced or collected the genomes of the type strains of species of Natrinema and Haloterrigena and we have carried out a comparative genomic analysis in order to clarify the controversy related to these two genera. The phylogenomic analysis based on the comparison of 525 translated single-copy orthologous genes and the Overall Genome Relatedness Indexes (i.e., AAI, POCP, ANI, and dDDH) clearly indicate that the species Haloterrigena hispanica, Haloterrigena limicola, Haloterrigena longa, Haloterrigena mahii, Haloterrigena saccharevitans, Haloterrigena thermotolerans, and Halopiger salifodinae should be transferred to the genus Natrinema, as Natrinema hispanicum, Natrinema limicola, Natrinema longum, Natrinema mahii, Natrinema saccharevitans, Natrinema thermotolerans, and Natrinema salifodinae, respectively. On the contrary, the species Haloterrigena turkmenica, Haloterrigena salifodinae, and Haloterrigena salina will remain as the only representative species of the genus Haloterrigena. Besides, the species Haloterrigena daqingensis should be reclassified as a member of the genus Natronorubrum, as Natronorubrum daqingense. At the species level, Haloterrigena jeotgali and Natrinema ejinorense should be considered as a later heterotypic synonyms of the species Haloterrigena (Natrinema) thermotolerans and Haloterrigena (Natrinema) longa, respectively. Synteny analysis and phenotypic features also supported those proposals.
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Affiliation(s)
- Rafael R de la Haba
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla, Sevilla, Spain
| | - Hiroaki Minegishi
- Department of Applied Chemistry, Faculty of Science and Engineering, Toyo University, Kawagoe, Japan
| | | | - Yasuhiro Shimane
- Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan
| | - Antonio Ventosa
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla, Sevilla, Spain
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Rekhi P, Goswami M, Ramakrishna S, Debnath M. Polyhydroxyalkanoates biopolymers toward decarbonizing economy and sustainable future. Crit Rev Biotechnol 2021; 42:668-692. [PMID: 34645360 DOI: 10.1080/07388551.2021.1960265] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Polymers are synonymous with the modern way of living. However, polymers with a large carbon footprint, especially those derived from nonrenewable petrochemical sources, are increasingly perceived as detrimental to the environment and a sustainable future. Polyhydroxyalkanoate (PHA) is a microbial biopolymer and a plausible alternative for renewable sources. However, PHA in its monomeric forms has very limited applications due to its limited flexibility, tensile strength, and moldability. Herein, the life cycle of PHA molecules, from biosynthesis to commercial utilization for diverse applications is discussed. For clarity, the applications of this bioplastic biocomposite material are further segregated into two domains, namely, the industrial sector and the medical sector. The industry sectors reviewed here include food packaging, textiles, agriculture, automotive, and electronics. High-value addition of PHA for a sustainable future can be foreseen in the medical domain. Properties such as biodegradability and biocompatibility make PHA a suitable candidate for decarbonizing biomaterials during tissue repair, organ reconstruction, drug delivery, bone tissue engineering, and chemotherapeutics.
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Affiliation(s)
- Pavni Rekhi
- Department of Biosciences, Manipal University Jaipur, Jaipur, India
| | - Moushmi Goswami
- Department of Biosciences, Manipal University Jaipur, Jaipur, India
| | - Seeram Ramakrishna
- Department of Mechanical Engineering, National University of Singapore, Singapore, Singapore
| | - Mousumi Debnath
- Department of Biosciences, Manipal University Jaipur, Jaipur, India
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Mohanrasu K, Guru Raj Rao R, Dinesh GH, Zhang K, Sudhakar M, Pugazhendhi A, Jeyakanthan J, Ponnuchamy K, Govarthanan M, Arun A. Production and characterization of biodegradable polyhydroxybutyrate by Micrococcus luteus isolated from marine environment. Int J Biol Macromol 2021; 186:125-134. [PMID: 34246666 DOI: 10.1016/j.ijbiomac.2021.07.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 07/02/2021] [Accepted: 07/03/2021] [Indexed: 11/26/2022]
Abstract
Marine microorganisms are reported to produce polyhydroxybutyrate (PHB) that has wide range of medical and industrial applications with the advantage of biodegradability. PHBs are synthesized as an energy and carbon storage element under metabolic pressure. The scope of this work is enhancing PHB production using marine microbial isolate, Micrococcus luteus by selectively optimizing various growth conditions such as different media components and growth parameters that influence the cell growth and PHB production were sampled. Micrococcus luteus produced 7.54 g/L of PHB utilizing glucose as a carbon source and ammonium sulphate as a nitrogen source with maximum efficiency. The same optimized operational conditions were further employed in batch fermentation over a time span of 72 h. Interestingly higher cell dry weight of 21.52 g/L with PHB yield of 12.18 g/L and 56.59% polymer content was observed in batch fermentation studies at 64 h. The chemical nature of the extracted polymer was validated with physio-chemical experiments and was at par with the commercially available PHB. This study will spotlight M. luteus as a potential source for large-scale industrial production of PHB with reducing environmental pollutions.
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Affiliation(s)
- K Mohanrasu
- Department of Microbiology, Alagappa University, Karaikudi, Tamil Nadu, India.
| | - R Guru Raj Rao
- Structural Biology and Bio-Computing Lab, Department of Bioinformatics, Alagappa University, Karaikudi 630 004, Tamil Nadu, India
| | - G H Dinesh
- Department of Microbiology, Alagappa University, Karaikudi, Tamil Nadu, India
| | - Kunyu Zhang
- School of Chemical Engineering and Technology, Tianjin University, China
| | - Muniyasamy Sudhakar
- CSIR Chemical Cluster, Advanced Polymers and Composites Research, Pretoria, South Africa; Dept of Chemistry, Nelson Mandela University, Port Elizabeth, South Africa
| | - A Pugazhendhi
- Innovative Green Product Synthesis and Renewable Environment Development Research Group, Faculty of Environment and Labour Safety, Ton Duc Thang University, Ho Chi Minh City, Viet Nam
| | - J Jeyakanthan
- Structural Biology and Bio-Computing Lab, Department of Bioinformatics, Alagappa University, Karaikudi 630 004, Tamil Nadu, India
| | - Kumar Ponnuchamy
- Department of Animal Health and Management, Alagappa University, Karaikudi, Tamil Nadu 630003, India
| | - M Govarthanan
- Department of Environmental Engineering, Kyungpook National University, Daegu, South Korea.
| | - A Arun
- Department of Microbiology, Alagappa University, Karaikudi, Tamil Nadu, India.
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Ghosh S, Greiserman S, Chemodanov A, Slegers PM, Belgorodsky B, Epstein M, Kribus A, Gozin M, Chen GQ, Golberg A. Polyhydroxyalkanoates and biochar from green macroalgal Ulva sp. biomass subcritical hydrolysates: Process optimization and a priori economic and greenhouse emissions break-even analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 770:145281. [PMID: 33517017 DOI: 10.1016/j.scitotenv.2021.145281] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 01/14/2021] [Accepted: 01/16/2021] [Indexed: 06/12/2023]
Abstract
Although macroalgae biomass is an emerging sustainable feedstock for biorefineries, the optimum process parameters for their hydrolysis and fermentation are still not known. In the present study, the simultaneous production of polyhydroxyalkanoates (PHA) and biochar from green macroalgae Ulva sp. is examined, applying subcritical water hydrolysis and Haloferax mediterranei fermentation. First, the effects of temperature, treatment time, salinity, and solid load on the biomass and PHA productivity were optimized following the Taguchi method. Hydrolysis at 170 °C, 20 min residence time, 38 g L-1 salinity with a seaweed solid load of 5% led to the maximum PHA yield of 0.104 g g-1Ulva and a biochar yield of 0.194 ± 1.23 g g-1Ulva. Second, the effect of different initial culture densities on the biomass and PHA productivity was studied. An initial culture density of 50 g L-1 led to the maximum volumetric PHA productivity of 0.024 ± 0.002 g L-1 h-1 with a maximum PHA content of 49.38 ± 0.3% w/w Sensitivity analysis shows that within 90% confidence, the annual PHA production from Ulva sp. is 148.14 g PHA m-2 year-1 with an annual biochar production of 42.6 g m-2 year-1. Priori economic and greenhouse gas break-even analyses of the process were done to estimate annual revenues and allowable greenhouse gas emissions. The study illustrates that PHA production from seaweed hydrolysate using extreme halophiles coupled to biochar production could become a benign and promising step in a marine biorefinery.
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Affiliation(s)
- Supratim Ghosh
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel.
| | - Semion Greiserman
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Alexander Chemodanov
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Petronella Margaretha Slegers
- Operations Research and Logistics, Wageningen University & Research, P.O. Box 8130, 6700 EW Wageningen, the Netherlands
| | - Bogdan Belgorodsky
- School of Chemistry, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Michael Epstein
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Abraham Kribus
- School of Mechanical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Michael Gozin
- School of Chemistry, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Guo-Qiang Chen
- Center for Synthetic and Systems Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Alexander Golberg
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
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Haloarchaea as Cell Factories to Produce Bioplastics. Mar Drugs 2021; 19:md19030159. [PMID: 33803653 PMCID: PMC8003077 DOI: 10.3390/md19030159] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/03/2021] [Accepted: 03/16/2021] [Indexed: 11/16/2022] Open
Abstract
Plastic pollution is a worldwide concern causing the death of animals (mainly aquatic fauna) and environmental deterioration. Plastic recycling is, in most cases, difficult or even impossible. For this reason, new research lines are emerging to identify highly biodegradable bioplastics or plastic formulations that are more environmentally friendly than current ones. In this context, microbes, capable of synthesizing bioplastics, were revealed to be good models to design strategies in which microorganisms can be used as cell factories. Recently, special interest has been paid to haloarchaea due to the capability of some species to produce significant concentrations of polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PHB), and polyhydroxyvalerate (PHV) when growing under a specific nutritional status. The growth of those microorganisms at the pilot or industrial scale offers several advantages compared to that of other microbes that are bioplastic producers. This review summarizes the state of the art of bioplastic production and the most recent findings regarding the production of bioplastics by halophilic microorganisms with special emphasis on haloarchaea. Some protocols to produce/analyze bioplastics are highlighted here to shed light on the potential use of haloarchaea at the industrial scale to produce valuable products, thus minimizing environmental pollution by plastics made from petroleum.
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Production of Poly(3-Hydroxybutyrate) by Haloarcula, Halorubrum, and Natrinema Haloarchaeal Genera Using Starch as a Carbon Source. ACTA ACUST UNITED AC 2021; 2021:8888712. [PMID: 33574733 PMCID: PMC7860971 DOI: 10.1155/2021/8888712] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 01/15/2021] [Accepted: 01/19/2021] [Indexed: 11/17/2022]
Abstract
Microbial production of bioplastics, derived from poly(3-hydroxybutyrate) (PHB), have provided a promising alternative towards plastic pollution. Compared to other extremophiles, halophilic archaea are considered as cell factories for PHB production by using renewable, inexpensive carbon sources, thus decreasing the fermentation cost. This study is aimed at screening 33 halophilic archaea isolated from three enrichment cultures from Tunisian hypersaline lake, Chott El Jerid, using starch as the sole carbon source by Nile Red/Sudan Black staining and further confirmed by PCR amplification of phaC and phaE polymerase genes. 14 isolates have been recognized as positive candidates for PHA production and detected during both seasons. The identification of these strains through 16S rRNA gene analyses showed their affiliation to Halorubrum, Natrinema, and Haloarcula genera. Among them, three PHB-producing strains, CEJ34-14, CEJ5-14, and CEJ48-10, related to Halorubrum chaoviator, Natrinema pallidum, and Haloarcula tradensis were found to be the best ones reaching values of 9.25, 7.11, and 1.42% of cell dry weight (CDW), respectively. Our findings highlighted that Halorubrum, Natrinema, and Haloarcula genera were promising candidates for PHB production using soluble starch as a carbon source under high salinity (250 g L−1 NaCl).
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Kasirajan L, Maupin-Furlow JA. Halophilic archaea and their potential to generate renewable fuels and chemicals. Biotechnol Bioeng 2020; 118:1066-1090. [PMID: 33241850 DOI: 10.1002/bit.27639] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 10/27/2020] [Accepted: 11/17/2020] [Indexed: 12/16/2022]
Abstract
Lignocellulosic biofuels and chemicals have great potential to reduce our dependence on fossil fuels and mitigate air pollution by cutting down on greenhouse gas emissions. Chemical, thermal, and enzymatic processes are used to release the sugars from the lignocellulosic biomass for conversion to biofuels. These processes often operate at extreme pH conditions, high salt concentrations, and/or high temperature. These harsh treatments add to the cost of the biofuels, as most known biocatalysts do not operate under these conditions. To increase the economic feasibility of biofuel production, microorganisms that thrive in extreme conditions are considered as ideal resources to generate biofuels and value-added products. Halophilic archaea (haloarchaea) are isolated from hypersaline ecosystems with high salt concentrations approaching saturation (1.5-5 M salt concentration) including environments with extremes in pH and/or temperature. The unique traits of haloarchaea and their enzymes that enable them to sustain catalytic activity in these environments make them attractive resources for use in bioconversion processes that must occur across a wide range of industrial conditions. Biocatalysts (enzymes) derived from haloarchaea occupy a unique niche in organic solvent, salt-based, and detergent industries. This review focuses on the use of haloarchaea and their enzymes to develop and improve biofuel production. The review also highlights how haloarchaea produce value-added products, such as antibiotics, carotenoids, and bioplastic precursors, and can do so using feedstocks considered "too salty" for most microbial processes including wastes from the olive-mill, shell fish, and biodiesel industries.
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Affiliation(s)
- Lakshmi Kasirajan
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, USA.,Division of Crop Improvement, ICAR Sugarcane Breeding Institute, Coimbatore, India
| | - Julie A Maupin-Furlow
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, USA.,Genetics Institute, University of Florida, Gainesville, Florida, USA
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14
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Raza ZA, Khalil S, Abid S. Recent progress in development and chemical modification of poly(hydroxybutyrate)-based blends for potential medical applications. Int J Biol Macromol 2020; 160:77-100. [DOI: 10.1016/j.ijbiomac.2020.05.114] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 04/25/2020] [Accepted: 05/15/2020] [Indexed: 02/06/2023]
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15
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El-malek FA, Farag A, Omar S, Khairy H. Polyhydroxyalkanoates (PHA) from Halomonas pacifica ASL10 and Halomonas salifodiane ASL11 isolated from Mariout salt lakes. Int J Biol Macromol 2020; 161:1318-1328. [DOI: 10.1016/j.ijbiomac.2020.07.258] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/22/2020] [Accepted: 07/23/2020] [Indexed: 12/22/2022]
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16
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Umemura RT, Felisberti MI. Plasticization of poly(3‐hydroxybutyrate) with triethyl citrate: Thermal and mechanical properties, morphology, and kinetics of crystallization. J Appl Polym Sci 2020. [DOI: 10.1002/app.49990] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Mahansaria R, Bhowmik S, Dhara A, Saha A, Mandal MK, Ghosh R, Mukherjee J. Production enhancement of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) in Halogeometricum borinquense, characterization of the bioplastic and desalination of the bioreactor effluent. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.04.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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18
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Mitra R, Xu T, Xiang H, Han J. Current developments on polyhydroxyalkanoates synthesis by using halophiles as a promising cell factory. Microb Cell Fact 2020; 19:86. [PMID: 32264891 PMCID: PMC7137286 DOI: 10.1186/s12934-020-01342-z] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Accepted: 03/26/2020] [Indexed: 11/17/2022] Open
Abstract
Plastic pollution is a severe threat to our environment which necessitates implementation of bioplastics to realize sustainable development for a green world. Polyhydroxyalkanoates (PHA) represent one of the potential candidates for these bioplastics. However, a major challenge faced by PHA is the high production cost which limits its commercial application. Halophiles are considered to be a promising cell factory for PHA synthesis due to its several unique characteristics including high salinity requirement preventing microbial contamination, high intracellular osmotic pressure allowing easy cell lysis for PHA recovery, and capability to utilize wide spectrum of low-cost substrates. Optimization of fermentation parameters has made it plausible to achieve large-scale production at low cost by using halophiles. Further deeper insights into halophiles have revealed the existence of diversified and even novel PHA synthetic pathways within different halophilic species that greatly affects PHA type. Thus, precise metabolic engineering of halophiles with the help of advanced tools and strategies have led to more efficient microbial cell factory for PHA production. This review is an endeavour to summarize the various research achievements in these areas which will help the readers to understand the current developments as well as the future efforts in PHA research.
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Affiliation(s)
- Ruchira Mitra
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, People's Republic of China.,International College, University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Tong Xu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, People's Republic of China
| | - Hua Xiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, People's Republic of China. .,College of Life Science, University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
| | - Jing Han
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, People's Republic of China. .,College of Life Science, University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China.
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19
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Application of osmotic challenge for enrichment of microbial consortia in polyhydroxyalkanoates producing thermophilic and thermotolerant bacteria and their subsequent isolation. Int J Biol Macromol 2020; 144:698-704. [DOI: 10.1016/j.ijbiomac.2019.12.128] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/04/2019] [Accepted: 12/15/2019] [Indexed: 12/23/2022]
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20
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Ben Abdallah M, Karray F, Sayadi S. Production of Polyhydroxyalkanoates by Two Halophilic Archaeal Isolates from Chott El Jerid Using Inexpensive Carbon Sources. Biomolecules 2020; 10:biom10010109. [PMID: 31936380 PMCID: PMC7022696 DOI: 10.3390/biom10010109] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 12/28/2019] [Accepted: 01/06/2020] [Indexed: 11/16/2022] Open
Abstract
The large use of conventional plastics has resulted in serious environmental problems. Polyhydroxyalkanoates represent a potent replacement to synthetic plastics because of their biodegradable nature. This study aimed to screen bacteria and archaea isolated from an extreme environment, the salt lake Chott El Jerid for the accumulation of these inclusions. Among them, two archaeal strains showed positive results with phenotypic and genotypic methods. Phylogenetic analysis, based on the 16S rRNA gene, indicated that polyhydroxyalkanoate (PHA)-producing archaeal isolates CEJGTEA101 and CEJEA36 were related to Natrinema altunense and Haloterrigena jeotgali, respectively. Gas chromatography and UV-visible spectrophotometric analyses revealed that the PHA were identified as polyhydroxybutyrate and polyhydroxyvalerate, respectively. According to gas chromatography analysis, the strain CEJGTEA101 produced maximum yield of 7 wt % at 37 °C; pH 6.5; 20% NaCl and the strain CEJEA36 produced 3.6 wt % at 37 °C; pH 7; 25% NaCl in a medium supplemented with 2% glucose. Under nutritionally optimal cultivation conditions, polymers were extracted from these strains and were determined by gravimetric analysis yielding PHA production of 35% and 25% of cell dry weight. In conclusion, optimization of PHA production from inexpensive industrial wastes and carbon sources has considerable interest for reducing costs and obtaining high yield.
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Affiliation(s)
- Manel Ben Abdallah
- Laboratory of Environmental Bioprocesses, Centre of Biotechnology of Sfax, BP 1177, Sfax 3018, Tunisia; (M.B.A.); (F.K.)
| | - Fatma Karray
- Laboratory of Environmental Bioprocesses, Centre of Biotechnology of Sfax, BP 1177, Sfax 3018, Tunisia; (M.B.A.); (F.K.)
| | - Sami Sayadi
- Center for Sustainable Development, College of Arts and Sciences, Qatar University, Doha 2713, Qatar
- Correspondence:
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21
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Genome Sequences and Methylation Patterns of Natrinema versiforme BOL5-4 and Natrinema pallidum BOL6-1, Two Extremely Halophilic Archaea from a Bolivian Salt Mine. Microbiol Resour Announc 2019; 8:8/33/e00810-19. [PMID: 31416876 PMCID: PMC6696651 DOI: 10.1128/mra.00810-19] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Two extremely halophilic archaea, namely, Natrinema versiforme BOL5-4 and Natrinema pallidum BOL6-1, were isolated from a Bolivian salt mine and their genomes sequenced using single-molecule real-time sequencing. The GC-rich genomes of BOL5-4 and BOL6-1 were 4.6 and 3.8 Mbp, respectively, with large chromosomes and multiple megaplasmids. Genome annotation was incorporated into HaloWeb and methylation patterns incorporated into REBASE. Two extremely halophilic archaea, namely, Natrinema versiforme BOL5-4 and Natrinema pallidum BOL6-1, were isolated from a Bolivian salt mine and their genomes sequenced using single-molecule real-time sequencing. The GC-rich genomes of BOL5-4 and BOL6-1 were 4.6 and 3.8 Mbp, respectively, with large chromosomes and multiple megaplasmids. Genome annotation was incorporated into HaloWeb and methylation patterns incorporated into REBASE.
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22
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Zheng Y, Chen JC, Ma YM, Chen GQ. Engineering biosynthesis of polyhydroxyalkanoates (PHA) for diversity and cost reduction. Metab Eng 2019; 58:82-93. [PMID: 31302223 DOI: 10.1016/j.ymben.2019.07.004] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 06/23/2019] [Accepted: 07/11/2019] [Indexed: 11/29/2022]
Abstract
PHA, a family of natural biopolymers aiming to replace non-degradable plastics for short-term usages, has been developed to include various structures such as short-chain-length (scl) and medium-chain-length (mcl) monomers as well as their copolymers. However, PHA market has been grown slowly since 1980s due to limited variety with good mechanical properties and the high production cost. Here, we review most updated strategies or approaches including metabolic engineering, synthetic biology and morphology engineering on expanding PHA diversity, reducing production cost and enhancing PHA production. The extremophilic Halomonas spp. are taken as examples to show the feasibility and challenges to develop next generation industrial biotechnology (NGIB) for producing PHA more competitively.
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Affiliation(s)
- Yang Zheng
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China; School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Jin-Chun Chen
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China; School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yi-Ming Ma
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China; School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Guo-Qiang Chen
- Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, 100084, China; School of Life Sciences, Tsinghua University, Beijing, 100084, China; Center for Synthetic and Systems Biology, Tsinghua University, Beijing, 100084, China; Center for Nano- and Micro-Mechanics, Tsinghua University, Beijing, 100084, China; Dept of Chemical Engineering, Tsinghua University, Beijing, 100084, China.
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23
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Koller M. Polyhydroxyalkanoate Biosynthesis at the Edge of Water Activitiy-Haloarchaea as Biopolyester Factories. Bioengineering (Basel) 2019; 6:bioengineering6020034. [PMID: 30995811 PMCID: PMC6631277 DOI: 10.3390/bioengineering6020034] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 04/03/2019] [Accepted: 04/04/2019] [Indexed: 11/16/2022] Open
Abstract
Haloarchaea, the extremely halophilic branch of the Archaea domain, encompass a steadily increasing number of genera and associated species which accumulate polyhydroxyalkanoate biopolyesters in their cytoplasm. Such ancient organisms, which thrive in highly challenging, often hostile habitats characterized by salinities between 100 and 300 g/L NaCl, have the potential to outperform established polyhydroxyalkanoate production strains. As detailed in the review, this optimization presents due to multifarious reasons, including: cultivation setups at extreme salinities can be performed at minimized sterility precautions by excluding the growth of microbial contaminants; the high inner-osmotic pressure in haloarchaea cells facilitates the recovery of intracellular biopolyester granules by cell disintegration in hypo-osmotic media; many haloarchaea utilize carbon-rich waste streams as main substrates for growth and polyhydroxyalkanoate biosynthesis, which allows coupling polyhydroxyalkanoate production with bio-economic waste management; finally, in many cases, haloarchaea are reported to produce copolyesters from structurally unrelated inexpensive substrates, and polyhydroxyalkanoate biosynthesis often occurs in parallel to the production of additional marketable bio-products like pigments or polysaccharides. This review summarizes the current knowledge about polyhydroxyalkanoate production by diverse haloarchaea; this covers the detection of new haloarchaea producing polyhydroxyalkanoates, understanding the genetic and enzymatic particularities of such organisms, kinetic aspects, material characterization, upscaling and techno-economic and life cycle assessment.
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Affiliation(s)
- Martin Koller
- University of Graz, Office of Research Management and Service, c/o Institute of Chemistry, NAWI Graz, Heinrichstrasse 28/III, 8010 Graz, Austria.
- ARENA-Association for Resource Efficient and Sustainable Technologies, Inffeldgasse 21b, 8010 Graz, Austria.
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Medium optimization for polyhydroxyalkanoate production by Pseudomonas pseudoalcaligenes strain Te using D-optimal design. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.01.039] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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25
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Ghosh S, Gnaim R, Greiserman S, Fadeev L, Gozin M, Golberg A. Macroalgal biomass subcritical hydrolysates for the production of polyhydroxyalkanoate (PHA) by Haloferax mediterranei. BIORESOURCE TECHNOLOGY 2019; 271:166-173. [PMID: 30268011 DOI: 10.1016/j.biortech.2018.09.108] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 09/19/2018] [Accepted: 09/20/2018] [Indexed: 05/11/2023]
Abstract
Non-conventional carbon sources, such as macroalgae, are sustainable alternatives for large-scale production of biopolymers. The present study examined macroalgae-derived carbohydrates, as carbon sources for the production of polyhydroxyalkanoates (PHAs) by Haloferax mediterranei. Simulants of the hydrolysates of seven different macroalgal biomasses were prepared and the PHA production was studied. A maximum biomass concentration with maximum PHA content was detected in medium prepared from green macroalgae. The highest cell dry weight and PHA concentrations were 3.8 ± 0.2 g·L-1 and 2.2 ± 0.12 g·L-1 respectively when Haloferax mediterranei was grown in 25% (w/w) of Ulva sp. hydrolysate, at 42 °C temperature and initial pH of 7.2. Poly(3-hydroxy-butyrate-co-3-hydroxyvalerate was the major PHA constituent. The present study demonstrated that Ulva sp. is a promising feedstock for PHA production.
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Affiliation(s)
- Supratim Ghosh
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel; School of Chemistry, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Rima Gnaim
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Semion Greiserman
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ludmila Fadeev
- School of Chemistry, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Michael Gozin
- School of Chemistry, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel
| | - Alexander Golberg
- Porter School of the Environment and Earth Sciences, Faculty of Exact Science, Tel Aviv University, Tel Aviv 69978, Israel.
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Sedlacek P, Slaninova E, Koller M, Nebesarova J, Marova I, Krzyzanek V, Obruca S. PHA granules help bacterial cells to preserve cell integrity when exposed to sudden osmotic imbalances. N Biotechnol 2018; 49:129-136. [PMID: 30389520 DOI: 10.1016/j.nbt.2018.10.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 10/29/2018] [Accepted: 10/29/2018] [Indexed: 11/28/2022]
Abstract
Polyhydroxyalkanoates (PHA) are microbial polyesters which accumulate as intracellular granules in numerous prokaryotes and mainly serve as storage materials; beyond this primary function, PHA also enhance the robustness of bacteria against various stress factors. We have observed that the presence of PHA in bacterial cells substantially enhances their ability to maintain cell integrity when suddenly exposed to osmotic imbalances. In the case of the non-halophilic bacterium Cupriavidus necator, the presence of PHA decreased plasmolysis-induced cytoplasmic membrane damage during osmotic up-shock, which subsequently enabled the cells to withstand subsequent osmotic downshock. In contrast, sudden induction of osmotic up- and subsequent down-shock resulted in massive hypotonic lysis of non-PHA containing cells as determined by Transmission Electron Microscopy and Thermogravimetrical Analysis. Furthermore, a protective effect of PHA against hypotonic lysis was also observed in the case of the halophilic bacterium Halomonas halophila; here, challenged PHA-rich cells were capable of retaining cell integrity more effectively than their PHA-poor counterparts. Hence, it appears that the fact that PHA granules, as an added value to their primary storage function, protect halophiles from the harmful effect of osmotic down-shock might explain why PHA accumulation is such a common feature among halophilic prokaryotes. The results of this study, apart from their fundamental importance, are also of practical biotechnological significance: because PHA-rich bacterial cells are resistant to osmotic imbalances, they could be utilized in in-situ bioremediation technologies or during enrichment of mixed microbial consortia in PHA producers under conditions of fluctuating salinity.
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Affiliation(s)
- Petr Sedlacek
- Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00, Brno, Czech Republic
| | - Eva Slaninova
- Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00, Brno, Czech Republic
| | - Martin Koller
- Institute of Chemistry, NAWI Graz, University of Graz, Heinrichstrasse 28/III, 8010, Graz, Austria; ARENA Arbeitsgemeinschaft für Ressourcenschonende & Nachhaltige Technologien, Inffeldgasse 21b, 8010, Graz, Austria
| | - Jana Nebesarova
- The Czech Academy of Sciences, Biology Centre, v.v.i., Branisovska 31, 370 05, Ceske Budejovice, Czech Republic; University of South Bohemia, Faculty of Science, Branisovska 31, 370 05, Ceske Budejovice, Czech Republic
| | - Ivana Marova
- Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00, Brno, Czech Republic
| | - Vladislav Krzyzanek
- The Czech Academy of Sciences, Institute of Scientific Instruments, v.v.i., Kralovopolska 147, 612 64, Brno, Czech Republic
| | - Stanislav Obruca
- Faculty of Chemistry, Brno University of Technology, Purkynova 118, 612 00, Brno, Czech Republic.
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Affiliation(s)
- Xu Zhang
- MOE Lab of Bioinformatics; School of Life Sciences; Tsinghua University; Beijing 100084 China
- Center for Synthetic and Systems Biology; Tsinghua University; Beijing 100084 China
| | - Yina Lin
- MOE Lab of Bioinformatics; School of Life Sciences; Tsinghua University; Beijing 100084 China
- Center for Synthetic and Systems Biology; Tsinghua University; Beijing 100084 China
- Tsinghua-Peking Center for Life Sciences; Tsinghua University; Beijing 100084 China
| | - Guo-Qiang Chen
- MOE Lab of Bioinformatics; School of Life Sciences; Tsinghua University; Beijing 100084 China
- Center for Synthetic and Systems Biology; Tsinghua University; Beijing 100084 China
- Tsinghua-Peking Center for Life Sciences; Tsinghua University; Beijing 100084 China
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