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Fukala I, Kučera I. Natural Polyhydroxyalkanoates-An Overview of Bacterial Production Methods. Molecules 2024; 29:2293. [PMID: 38792154 PMCID: PMC11124392 DOI: 10.3390/molecules29102293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/05/2024] [Accepted: 05/10/2024] [Indexed: 05/26/2024] Open
Abstract
Polyhydroxyalkanoates (PHAs) are intracellular biopolymers that microorganisms use for energy and carbon storage. They are mechanically similar to petrochemical plastics when chemically extracted, but are completely biodegradable. While they have potential as a replacement for petrochemical plastics, their high production cost using traditional carbon sources remains a significant challenge. One potential solution is to modify heterotrophic PHA-producing strains to utilize alternative carbon sources. An alternative approach is to utilize methylotrophic or autotrophic strains. This article provides an overview of bacterial strains employed for PHA production, with a particular focus on those exhibiting the highest PHA content in dry cell mass. The strains are organized according to their carbon source utilization, encompassing autotrophy (utilizing CO2, CO) and methylotrophy (utilizing reduced single-carbon substrates) to heterotrophy (utilizing more traditional and alternative substrates).
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Affiliation(s)
| | - Igor Kučera
- Department of Biochemistry, Faculty of Science, Masaryk University, Kotlářská 267/2, CZ-61137 Brno, Czech Republic;
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2
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Bhatia SK, Patel AK, Yang YH. The green revolution of food waste upcycling to produce polyhydroxyalkanoates. Trends Biotechnol 2024:S0167-7799(24)00066-0. [PMID: 38582658 DOI: 10.1016/j.tibtech.2024.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 02/16/2024] [Accepted: 03/07/2024] [Indexed: 04/08/2024]
Abstract
This review emphasizes the urgent need for food waste upcycling as a response to the mounting global food waste crisis. Focusing on polyhydroxyalkanoates (PHAs) as an alternative to traditional plastics, it examines the potential of various food wastes as feedstock for microbial fermentation and PHA production. The upcycling of food waste including cheese whey, waste cooking oil, coffee waste, and animal fat is an innovative practice for food waste management. This approach not only mitigates environmental impacts but also contributes to sustainable development and economic growth. Downstream processing techniques for PHAs are discussed, highlighting their role in obtaining high-quality materials. The study also addresses sustainability considerations, emphasizing biodegradability and recycling, while acknowledging the challenges associated with this path.
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Affiliation(s)
- Shashi Kant Bhatia
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea; Institute for Ubiquitous Information Technology and Applications, Seoul 05029, Republic of Korea
| | - Anil Kumar Patel
- Institute of Aquatic Science and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Yung-Hun Yang
- Department of Biological Engineering, College of Engineering, Konkuk University, Seoul 05029, Republic of Korea; Institute for Ubiquitous Information Technology and Applications, Seoul 05029, Republic of Korea.
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3
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Peña-Castro JM, Muñoz-Páez KM, Robledo-Narvaez PN, Vázquez-Núñez E. Engineering the Metabolic Landscape of Microorganisms for Lignocellulosic Conversion. Microorganisms 2023; 11:2197. [PMID: 37764041 PMCID: PMC10535843 DOI: 10.3390/microorganisms11092197] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/16/2023] [Accepted: 08/18/2023] [Indexed: 09/29/2023] Open
Abstract
Bacteria and yeast are being intensively used to produce biofuels and high-added-value products by using plant biomass derivatives as substrates. The number of microorganisms available for industrial processes is increasing thanks to biotechnological improvements to enhance their productivity and yield through microbial metabolic engineering and laboratory evolution. This is allowing the traditional industrial processes for biofuel production, which included multiple steps, to be improved through the consolidation of single-step processes, reducing the time of the global process, and increasing the yield and operational conditions in terms of the desired products. Engineered microorganisms are now capable of using feedstocks that they were unable to process before their modification, opening broader possibilities for establishing new markets in places where biomass is available. This review discusses metabolic engineering approaches that have been used to improve the microbial processing of biomass to convert the plant feedstock into fuels. Metabolically engineered microorganisms (MEMs) such as bacteria, yeasts, and microalgae are described, highlighting their performance and the biotechnological tools that were used to modify them. Finally, some examples of patents related to the MEMs are mentioned in order to contextualize their current industrial use.
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Affiliation(s)
- Julián Mario Peña-Castro
- Centro de Investigaciones Científicas, Instituto de Biotecnología, Universidad del Papaloapan, Tuxtepec 68301, Oaxaca, Mexico;
| | - Karla M. Muñoz-Páez
- CONAHCYT—Instituto de Ingeniería, Unidad Académica Juriquilla, Universidad Nacional Autónoma de México, Queretaro 76230, Queretaro, Mexico;
| | | | - Edgar Vázquez-Núñez
- Grupo de Investigación Sobre Aplicaciones Nano y Bio Tecnológicas para la Sostenibilidad (NanoBioTS), Departamento de Ingenierías Química, Electrónica y Biomédica, División de Ciencias e Ingenierías, Universidad de Guanajuato, Lomas del Bosque 103, Lomas del Campestre, León 37150, Guanajuato, Mexico
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4
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Xu M, Yang M, Sun H, Gao M, Wang Q, Wu C. Bioconversion of biowaste into renewable energy and resources: A sustainable strategy. ENVIRONMENTAL RESEARCH 2022; 214:113929. [PMID: 35868577 DOI: 10.1016/j.envres.2022.113929] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 07/07/2022] [Accepted: 07/15/2022] [Indexed: 05/27/2023]
Abstract
Due to its high amount of organic and biodegradable components that can be recycled, biowaste is not only a major cause of environmental contamination, but also a vast store of useful materials. The transformation of biowaste into energy and resources via biorefinery is an unavoidable trend, which could aid in reducing carbon emissions and alleviating the energy crisis in light of dwindling energy supplies and mounting environmental difficulties related with solid waste. In addition, the current pandemic and the difficult worldwide situation, with their effects on the economic, social, and environmental aspects of human life, have offered an opportunity to promote the transition to greener energy and sources. In this context, the current advancements and possible trends of utilizing widely available biowaste to produce key biofuels (such as biogas and biodiesel) and resources (such as organic acid, biodegradable plastic, protein product, biopesticide, bioflocculant, and compost) are studied in this review. To achieve the goal of circular bioeconomy, it is necessary to turn biowaste into high-value energy and resources utilizing biological processes. In addition, the usage of recycling technologies and the incorporation of bioconversion to enhance process performance are analyzed critically. Lastly, this work seeks to reduce a number of enduring obstacles to the recycling of biowaste for future use in the circular economy. Although it could alleviate the global energy issue, additional study, market analysis, and finance are necessary to commercialize alternative products and promote their future use. Utilization of biowaste should incorporate a comprehensive approach and a methodical style of thinking, which can facilitate product enhancement and decision optimization through multidisciplinary integration and data-driven techniques.
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Affiliation(s)
- Mingyue Xu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Min Yang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Haishu Sun
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Ming Gao
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, Beijing, 100083, China
| | - Qunhui Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, Beijing, 100083, China
| | - Chuanfu Wu
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, Beijing, 100083, China.
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5
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Gutschmann B, Huang B, Santolin L, Thiele I, Neubauer P, Riedel SL. Native feedstock options for the polyhydroxyalkanoate industry in Europe: A review. Microbiol Res 2022; 264:127177. [DOI: 10.1016/j.micres.2022.127177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 08/05/2022] [Accepted: 08/24/2022] [Indexed: 11/26/2022]
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6
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Gutschmann B, Högl TH, Huang B, Maldonado Simões M, Junne S, Neubauer P, Grimm T, Riedel SL. Polyhydroxyalkanoate production from animal by-products: Development of a pneumatic feeding system for solid fat/protein-emulsions. Microb Biotechnol 2022; 16:286-294. [PMID: 36168730 PMCID: PMC9871516 DOI: 10.1111/1751-7915.14150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 09/02/2022] [Accepted: 09/10/2022] [Indexed: 01/27/2023] Open
Abstract
Fat-containing animal by-product streams are locally available in large quantities. Depending on their quality, they can be inexpensive substrates for biotechnological processes. To accelerate industrial polyhydroxyalkanoate (PHA) bioplastic production, the development of efficient bioprocesses that are based on animal by-product streams is a promising approach to reduce overall production costs. However, the solid nature of animal by-product streams requires a tailor-made process development. In this study, a fat/protein-emulsion (FPE), which is a by-product stream from industrial-scale pharmaceutical heparin production and of which several hundred tons are available annually, was evaluated for PHA production with Ralstonia eutropha. The FPE was used as the sole source of carbon and nitrogen in shake flask and bioreactor cultivations. A tailored pneumatic feeding system was built for laboratory bioreactors to facilitate fed-batch cultivations with the solid FPE. The process yielded up to 51 g L-1 cell dry weight containing 71 wt% PHA with a space-time yield of 0.6 gPHA L-1 h-1 without using any carbon or nitrogen sources other than FPE. The presented approach highlights the potential of animal by-product stream valorization into PHA and contributes to a transition towards a circular bioeconomy.
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Affiliation(s)
- Björn Gutschmann
- Technische Universität Berlin, Chair of Bioprocess EngineeringBerlinGermany
| | - Thomas H. Högl
- Technische Universität Berlin, Chair of Bioprocess EngineeringBerlinGermany
| | - Boyang Huang
- Technische Universität Berlin, Chair of Bioprocess EngineeringBerlinGermany
| | | | - Stefan Junne
- Technische Universität Berlin, Chair of Bioprocess EngineeringBerlinGermany
| | - Peter Neubauer
- Technische Universität Berlin, Chair of Bioprocess EngineeringBerlinGermany
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7
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Lin L, Huang H, Zhang X, Dong L, Chen Y. Hydrogen-oxidizing bacteria and their applications in resource recovery and pollutant removal. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 835:155559. [PMID: 35483467 DOI: 10.1016/j.scitotenv.2022.155559] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 04/16/2022] [Accepted: 04/23/2022] [Indexed: 06/14/2023]
Abstract
Hydrogen oxidizing bacteria (HOB), a type of chemoautotroph, are a group of bacteria from different genera that share the ability to oxidize H2 and fix CO2 to provide energy and synthesize cellular material. Recently, HOB have received growing attention due to their potential for CO2 capture and waste recovery. This review provides a comprehensive overview of the biological characteristics of HOB and their application in resource recovery and pollutant removal. Firstly, the enzymes, genes and corresponding regulation systems responsible for the key metabolic processes of HOB are discussed in detail. Then, the enrichment and cultivation methods including the coupled water splitting-biosynthetic system cultivation, mixed cultivation and two-stage cultivation strategies for HOB are summarized, which is the critical prerequisite for their application. On the basis, recent advances of HOB application in the recovery of high-value products and the removal of pollutants are presented. Finally, the key points for future investigation are proposed that more attention should be paid to the main limitations in the large-scale industrial application of HOB, including the mass transfer rate of the gases, the safety of the production processes and products, and the commercial value of the products.
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Affiliation(s)
- Lin Lin
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Haining Huang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Xin Zhang
- Shanghai Municipal Engineering Design Institute (Group) Co. LTD, 901 Zhongshan North Second Rd, Shanghai 200092, China
| | - Lei Dong
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China; Shanghai Municipal Engineering Design Institute (Group) Co. LTD, 901 Zhongshan North Second Rd, Shanghai 200092, China
| | - Yinguang Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
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8
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Gutschmann B, Maldonado Simões M, Schiewe T, Schröter ES, Münzberg M, Neubauer P, Bockisch A, Riedel SL. Continuous feeding strategy for polyhydroxyalkanoate production from solid waste animal fat at laboratory- and pilot-scale. Microb Biotechnol 2022; 16:295-306. [PMID: 35921398 PMCID: PMC9871520 DOI: 10.1111/1751-7915.14104] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 06/03/2022] [Accepted: 06/05/2022] [Indexed: 01/27/2023] Open
Abstract
Bioconversion of waste animal fat (WAF) to polyhydroxyalkanoates (PHAs) is an approach to lower the production costs of these plastic alternatives. However, the solid nature of WAF requires a tailor-made process development. In this study, a double-jacket feeding system was built to thermally liquefy the WAF to employ a continuous feeding strategy. During laboratory-scale cultivations with Ralstonia eutropha Re2058/pCB113, 70% more PHA (45 gPHA L-1 ) and a 75% higher space-time yield (0.63 gPHA L-1 h-1 ) were achieved compared to previously reported fermentations with solid WAF. During the development process, growth and PHA formation were monitored in real-time by in-line photon density wave spectroscopy. The process robustness was further evaluated during scale-down fermentations employing an oscillating aeration, which did not alter the PHA yield although cells encountered periods of oxygen limitation. Flow cytometry with propidium iodide staining showed that more than two-thirds of the cells were viable at the end of the cultivation and viability was even little higher in the scale-down cultivations. Application of this feeding system at 150-L pilot-scale cultivation yielded in 31.5 gPHA L-1 , which is a promising result for the further scale-up to industrial scale.
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Affiliation(s)
- Björn Gutschmann
- Technische Universität BerlinChair of Bioprocess EngineeringBerlinGermany
| | | | | | - Edith S. Schröter
- Technische Universität BerlinChair of Bioprocess EngineeringBerlinGermany
| | | | - Peter Neubauer
- Technische Universität BerlinChair of Bioprocess EngineeringBerlinGermany
| | - Anika Bockisch
- Technische Universität BerlinChair of Bioprocess EngineeringBerlinGermany,Bio‐PAT e.VBerlinGermany
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9
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Anagnostopoulou C, Kontogiannopoulos KN, Gaspari M, Morlino MS, Assimopoulou AN, Kougias PG. Valorization of household food wastes to lactic acid production: A response surface methodology approach to optimize fermentation process. CHEMOSPHERE 2022; 296:133871. [PMID: 35157886 DOI: 10.1016/j.chemosphere.2022.133871] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/12/2022] [Accepted: 02/02/2022] [Indexed: 05/27/2023]
Abstract
Lactic acid is a valuable compound used in several industrial processes such as polymers, emulsifiers manufacturing, pharmaceutical, and cosmetic formulations. The present study aims to evaluate the potential use of food waste to produce lactic acid through fermentation, both by indigenous microbiota and by the bio-augmentation with two lactic acid bacteria, namely Lactobacillus plantarum BS17 and Lactobacillus casei BP2. Fermentation was studied both in batch and continuously fed anaerobic reactors at mesophilic conditions and a Response Surface Methodology approach was used to optimize the bioprocess performance and determine the environmental parameters (namely pH and time) that lead to the enhancement of lactic acid production during the batch fermentation by indigenous microorganisms. Results revealed an optimum set of conditions for lactic acid production at a pH value of 6.5 and a fermentation period of 3.5 days at 37 °C. Under these conditions lactic acid production reached a value of 23.07 g/L, which was very similar to the mathematically predicted ones, thus verifying the accuracy of the experimental design. This optimum set of conditions was further employed to examine the production of lactic acid under continuous fermentation operation. Furthermore, concentrations of volatile fatty acids and ethanol were monitored and found to be relatively low, with ethanol being the dominant by-product of fermentation, indicating the presence of heterofermentative bacteria in the food wastes. A final step of downstream process was performed resulting in the successful recovery of lactic acid with purity over 90%.
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Affiliation(s)
- Chrysa Anagnostopoulou
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece
| | | | - Maria Gaspari
- Soil and Water Resources Institute, Hellenic Agricultural Organisation Dimitra, Thermi, Thessaloniki, 57001, Greece
| | - Maria Silvia Morlino
- Department of Biology, University of Padova, Via U. Bassi 58/b, 35121, Padova, Italy
| | - Andreana N Assimopoulou
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece; Natural Products Research Centre of Excellence (NatPro-AUTh), Center of Interdisciplinary Research and Innovation of Aristotle University of Thessaloniki (CIRI-AUTh), Thessaloniki, 57001, Greece
| | - Panagiotis G Kougias
- Soil and Water Resources Institute, Hellenic Agricultural Organisation Dimitra, Thermi, Thessaloniki, 57001, Greece.
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10
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Brojanigo S, Gronchi N, Cazzorla T, Wong TS, Basaglia M, Favaro L, Casella S. Engineering Cupriavidus necator DSM 545 for the one-step conversion of starchy waste into polyhydroxyalkanoates. BIORESOURCE TECHNOLOGY 2022; 347:126383. [PMID: 34808314 DOI: 10.1016/j.biortech.2021.126383] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 06/13/2023]
Abstract
Starch-rich by-products could be efficiently exploited for polyhydroxyalkanoates (PHAs) production. Unfortunately, Cupriavidus necator DSM 545, one of the most efficient PHAs producers, is not able to grow on starch. In this study, a recombinant amylolytic strain of C. necator DSM 545 was developed for the one-step PHAs production from starchy residues, such as broken rice and purple sweet potato waste. The glucodextranase G1d from Arthrobacter globiformis I42 and the α-amylase amyZ from Zunongwangia profunda SM-A87 were co-expressed into C. necator DSM 545. The recombinant C. necator DSM 545 #11, selected for its promising hydrolytic activity, produced high biomass levels with noteworthy PHAs titers: 5.78 and 3.65 g/L from broken rice and purple sweet potato waste, respectively. This is the first report on the engineering of C. necator DSM 545 for efficient amylase production and paves the way to the one-step conversion of starchy waste into PHAs.
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Affiliation(s)
- Silvia Brojanigo
- Department of Agronomy Food Natural resources Animals and Environment (DAFNAE), Università degli Studi di Padova, Agripolis, Viale dell'Università 16, 35020 Legnaro, (PD), Italy
| | - Nicoletta Gronchi
- Department of Agronomy Food Natural resources Animals and Environment (DAFNAE), Università degli Studi di Padova, Agripolis, Viale dell'Università 16, 35020 Legnaro, (PD), Italy
| | - Tiziano Cazzorla
- Department of Agronomy Food Natural resources Animals and Environment (DAFNAE), Università degli Studi di Padova, Agripolis, Viale dell'Università 16, 35020 Legnaro, (PD), Italy
| | - Tuck Seng Wong
- Department of Chemical & Biological Engineering, The University of Sheffield, Sir Robert Hadfield Building, Mappin Street, Sheffield S1 3JD, United Kingdom; National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, 12120, Pathum Thani, Thailand
| | - Marina Basaglia
- Department of Agronomy Food Natural resources Animals and Environment (DAFNAE), Università degli Studi di Padova, Agripolis, Viale dell'Università 16, 35020 Legnaro, (PD), Italy
| | - Lorenzo Favaro
- Department of Agronomy Food Natural resources Animals and Environment (DAFNAE), Università degli Studi di Padova, Agripolis, Viale dell'Università 16, 35020 Legnaro, (PD), Italy.
| | - Sergio Casella
- Department of Agronomy Food Natural resources Animals and Environment (DAFNAE), Università degli Studi di Padova, Agripolis, Viale dell'Università 16, 35020 Legnaro, (PD), Italy
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11
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Acedos MG, Moreno-Cid J, Verdú F, González JA, Tena S, López JC. Exploring the potential of slaughterhouse waste valorization: Development and scale-up of a new bioprocess for medium-chain length polyhydroxyalkanoates production. CHEMOSPHERE 2022; 287:132401. [PMID: 34600930 DOI: 10.1016/j.chemosphere.2021.132401] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/19/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
The progressive increase of slaughterhouse waste production requires actions for both addressing an environmental issue and creating additional value within a biorefinery concept. In this regard, some of these animal by-products exhibit a significant content of fatty acids that could be efficiently converted into bioplastics such as polyhydroxyalkanoates (PHAs) by adequately performing substrate screening with producing bacterial strains and applying affordable pretreatments. One of the main challenges also relies on the difficulty to emulsify these fat-rich substrates within culture broth and make the fatty acids accessible for the producing bacteria. In this work, the potential of two fat-rich animal by-products, grease trap waste (GTW) and tallow-based jelly (TBJ), as inexpensive carbon sources for microbial growth and PHA production was evaluated for the first time. Upon substrate screening, using different pseudomonadal strains (P. resinovorans, P. putida GPo1, P. putida KT2440) and pretreatment conditions (autoclave-based, thermally-treated or saponified substrates), the highest growth and mcl-PHA production performance was obtained for P. resinovorans, thus producing up to 47% w/w mcl-PHA simply using hygienized GTW. The novel bioprocess described in this study was successfully scaled up to 5 and 15 L, resulting in CDW concentrations of 5.9-12.8 g L-1, mcl-PHA contents of 33-62% w/w and PHA yields of 0.1-0.4 gPHA g-1fatty acids, greatly depending on the substrate dosing strategy used and depending on culture conditions. Moreover, process robustness was confirmed along Test Series by the roughly stable monomeric composition of the biopolymer produced, mainly formed by 3-hydroxyoctanoate and 3-hydroxydecanoate. The research here conducted is crucial for the cost-effectiveness of mcl-PHA production along this new slaughterhouse waste-based biorefinery concept.
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Affiliation(s)
- Miguel G Acedos
- Biotechnology Department, AINIA, Parque Tecnológico de Valencia, Av/ Benjamín Franklin 5-11, 46980, Paterna, Valencia, Spain
| | - Juan Moreno-Cid
- R&D Department, Bionet Engineering, Av/ Azul, Parque Tecnológico Fuente Álamo, El Estrecho-Lobosillo, 30320, Fuente Álamo, Murcia, Spain
| | - Fuensanta Verdú
- R&D Department, Bionet Engineering, Av/ Azul, Parque Tecnológico Fuente Álamo, El Estrecho-Lobosillo, 30320, Fuente Álamo, Murcia, Spain
| | - José Antonio González
- R&D Department, Bionet Engineering, Av/ Azul, Parque Tecnológico Fuente Álamo, El Estrecho-Lobosillo, 30320, Fuente Álamo, Murcia, Spain
| | - Sara Tena
- Biotechnology Department, AINIA, Parque Tecnológico de Valencia, Av/ Benjamín Franklin 5-11, 46980, Paterna, Valencia, Spain
| | - Juan Carlos López
- Biotechnology Department, AINIA, Parque Tecnológico de Valencia, Av/ Benjamín Franklin 5-11, 46980, Paterna, Valencia, Spain.
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