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Emilia N, Pia SV, Tiina HP, Antti N, Anniina V, Anneli R, Michael L, Natalia RS. In vitro protein digestion and carbohydrate colon fermentation of microbial biomass samples from bacterial, filamentous fungus and yeast sources. Food Res Int 2024; 182:114146. [PMID: 38519176 DOI: 10.1016/j.foodres.2024.114146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/13/2024] [Accepted: 02/17/2024] [Indexed: 03/24/2024]
Abstract
This study evaluated the nutritional quality of different microbial biomass samples by assessing their protein digestibility and carbohydrate fermentability in the colon using in vitro methods. Four microbial samples were produced: one hydrogen-oxidizing bacterial strain (Nocardioides nitrophenolicus KGS-27), two strains of filamentous fungi (Rhizopus oligosporus and Paecilomyces variotii), and one yeast strain (Rhodotorula babjevae). The microorganisms were grown in bioreactors, harvested and dried before analysis. The commercial fungal product Quorn was used as a reference. The protein digestibility of the microbial samples was analysed using the INFOGEST in vitro model, followed by quantification of N-terminal amine groups. An in vitro faecal fermentation experiment was also performed to evaluate the degradation of carbohydrates in microbial biomass samples and formation of short-chain fatty acids (SCFA). The fungal biomass samples had higher protein hydrolysis (60-75 %) than the bacterial sample (12 %) and Quorn (45 %), while the yeast biomass had the highest protein digestibility (85 %). Heat-treatment of the biomass significantly reduced its protein digestibility. Total dietary fibre (DF) content of fungal biomass was 31 - 43 %(DW), mostly insoluble, whereas the bacterial biomass contained mainly soluble DF (total DF: 25.7 %, of which 23.5 % were soluble and 2.2 % insoluble). After 24 h of colonic in vitro fermentation, SCFA production from the biomass of Paecilomyces, Quorn and Rhodotorula was similar to that of wheat bran, while 17 % and 32 % less SCFA were produced from the biomass of Rhizopus and the bacterial strain, respectively. Further studies are needed to clarify the reasons for the observed differences in protein digestibility and DF fermentability, especially regarding the cell wall structures and role of post-processing.
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Affiliation(s)
- Nordlund Emilia
- VTT Technical Research Centre of Finland, Ltd, P.O. Box 1000, FI-02044, Finland.
| | | | | | - Nyyssölä Antti
- VTT Technical Research Centre of Finland, Ltd, P.O. Box 1000, FI-02044, Finland
| | - Valtonen Anniina
- VTT Technical Research Centre of Finland, Ltd, P.O. Box 1000, FI-02044, Finland; Nordic Umami Company Ltd., Karamalmintie 2, 02630 Espoo, Finland(1)
| | - Ritala Anneli
- VTT Technical Research Centre of Finland, Ltd, P.O. Box 1000, FI-02044, Finland
| | - Lienemann Michael
- VTT Technical Research Centre of Finland, Ltd, P.O. Box 1000, FI-02044, Finland
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2
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Zhang B, Cai C, Zhou Y. Iron and nitrogen regulate carbon transformation in a methanotroph-microalgae system. Sci Total Environ 2023; 904:166287. [PMID: 37591392 DOI: 10.1016/j.scitotenv.2023.166287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 08/11/2023] [Accepted: 08/12/2023] [Indexed: 08/19/2023]
Abstract
Nutrient supply is important for maintaining a methanotroph and microalgae (MOB-MG) system for biogas valorization. However, there is a lack of understanding regarding how key elements regulate the growth of a MOB-MG coculture. In this study, a MOB-MG coculture with high protein content (0.47 g/g biomass) was established from waste activated sludge using synthetic biogas. An increase in iron availability substantially stimulated the specific growth rate (from 0.18 to 0.62 day-1) and biogas conversion rate (from 26.81 to 106.57 mg-C L-1 day-1) of the coculture. Moreover, the protein content remained high (0.51 g/g biomass), and the total lipid content increased (from 0.09 to 0.14 g/g biomass). Nitrogen limitation apparently constrained the specific growth rate (from 0.64 to 0.28 day-1) and largely reduced the protein content (from 0.51 to 0.31 g/g biomass) of the coculture. Intriguingly, the lipid content remained unchanged after nitrogen was depleted. The eukaryotic community was consistently dominated by MG belonging to Chlorella, while the populations of MOB shifted from Methylococcus/Methylosinus to Methylocystis due to iron and nitrogen amendment. In addition, diverse non-methanotrophic heterotrophs were present in the community. Their presence neither compromised the performance of the coculture system nor affected the protein content of the biomass. However, these heterotrophs may contribute to high carbon conversion efficiency by utilizing the dissolved organic carbon released by MOB and MG. Overall, the findings highlight the vital roles of iron and nitrogen in achieving efficient conversion of biogas, fast growth of cells, and optimal biomass composition in a MOB-MG coculture system.
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Affiliation(s)
- Baorui Zhang
- Interdisciplinary Graduate Program, Nanyang Technological University, 61 Nanyang Drive, 637335, Singapore; Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore
| | - Chen Cai
- Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei, China.
| | - Yan Zhou
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
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3
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Woern C, Grossmann L. Microbial gas fermentation technology for sustainable food protein production. Biotechnol Adv 2023; 69:108240. [PMID: 37647973 DOI: 10.1016/j.biotechadv.2023.108240] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 08/16/2023] [Accepted: 08/21/2023] [Indexed: 09/01/2023]
Abstract
The development of novel, sustainable, and robust food production technologies represents one of the major pillars to address the most significant challenges humanity is going to face on earth in the upcoming decades - climate change, population growth, and resource depletion. The implementation of microfoods, i.e., foods formulated with ingredients from microbial cultivation, into the food supply chain has a huge potential to contribute towards energy-efficient and nutritious food manufacturing and represents a means to sustainably feed a growing world population. This review recapitulates and assesses the current state in the establishment and usage of gas fermenting bacteria as an innovative feedstock for protein production. In particular, we focus on the most promising representatives of this taxon: the hydrogen-oxidizing bacteria (hydrogenotrophs) and the methane-oxidizing bacteria (methanotrophs). These unicellular microorganisms can aerobically metabolize gaseous hydrogen and methane, respectively, to provide the required energy for building up cell material. A protein yield over 70% in the dry matter cell mass can be reached with no need for arable land and organic substrates making it a promising alternative to plant- and animal-based protein sources. We illuminate the holistic approach to incorporate protein extracts obtained from the cultivation of gas fermenting bacteria into microfoods. Herein, the fundamental properties of the bacteria, cultivation methods, downstream processing, and potential food applications are discussed. Moreover, this review covers existing and future challenges as well as sustainability aspects associated with the production of microbial protein through gas fermentation.
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Affiliation(s)
- Carlos Woern
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA
| | - Lutz Grossmann
- Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA.
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Gao L, Meng J, Dai W, Zhang Z, Dong H, Yuan Q, Zhang W, Liu S, Wu X. Deciphering cell wall sensors enabling the construction of robust P. pastoris for single-cell protein production. Biotechnol Biofuels Bioprod 2023; 16:178. [PMID: 37978550 PMCID: PMC10655344 DOI: 10.1186/s13068-023-02428-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 11/08/2023] [Indexed: 11/19/2023]
Abstract
Single-cell protein (SCP) production in the methylotrophic yeast Pichia pastoris has the potential to achieve a sustainable protein supply. However, improving the methanol fermentation efficiency and reducing carbon loss has been a long-standing challenge with far-reaching scientific and practical implications. Here, comparative transcriptomics revealed that PAS_0305, a gene directly associated with cell wall thickness under methanol stress, can be used as a target for unlocking cell wall sensors. Intracellular trehalose accumulation confirmed that cell wall sensors were activated after knocking out PAS_0305, which resulted in increased cell wall permeability. Genome-wide signal perturbations were transduced through the HOG module and the CWI pathway, which was confirmed to connected by Pbs2-Mkk. As a consequence of CWI pathway activation, ΔPAS_0305 elicited a rescue response of cell wall remodeling by increasing the β-1,3-glucan content and decreasing the chitin/mannose content. Remarkably, perturbations in global stress signals led to a fine-tuning of the metabolic network of ΔPAS_0305, resulting in a superior phenotype with highest crude protein and methanol conversion rate of 67.21% and 0.46 gDCW/g. Further genome-scale metabolic models were constructed to validate the experimental results, confirming that unlocking cell wall sensors resulted in maximized flux from methanol towards SCP and effectively addressing the issue of carbon loss in methanol fermentation. This work sheds new light on the potential of manipulating cellular signaling pathways to optimize metabolic networks and achieve exceptional phenotypic characteristics, providing new strategies for constructing versatile cell factories in P. pastoris.
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Affiliation(s)
- Le Gao
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Jiao Meng
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Wuling Dai
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Zhaokun Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Haofan Dong
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Qianqian Yuan
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Wuyuan Zhang
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin, 300308, China
| | - Shuguang Liu
- Beijing Chasing future Biotechnology Co., Ltd, Beijing, China
| | - Xin Wu
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, National Technology Innovation Center of Synthetic Biology, No. 32, Xiqi Road, Tianjin Airport Economic Park, Tianjin, 300308, China.
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Diaz-Bustamante ML, Keppler JK, Reyes LH, Alvarez Solano OA. Trends and prospects in dairy protein replacement in yogurt and cheese. Heliyon 2023; 9:e16974. [PMID: 37346362 PMCID: PMC10279912 DOI: 10.1016/j.heliyon.2023.e16974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 05/26/2023] [Accepted: 06/02/2023] [Indexed: 06/23/2023] Open
Abstract
There is a growing demand for nutritional, functional, and eco-friendly dairy products, which has increased the need for research regarding alternative and sustainable protein sources. Plant-based, single-cell (SCP), and recombinant proteins are being explored as alternatives to dairy proteins. Plant-Based Proteins (PBPs) are commonly used to replace total dairy protein. However, PBPs are generally mixed with dairy proteins to improve their functional properties, which makes them dependent on animal protein sources. In contrast, single-Cell Proteins (SCPs) and recombinant dairy proteins are promising alternatives for dairy protein replacement since they provide nutritional components, essential amino acids, and high protein yield and can use industrial and agricultural waste as carbon sources. Although alternative protein sources offer numerous advantages over conventional dairy proteins, several technical and sensory challenges must be addressed to fully incorporate them into cheese and yogurt products. Future research can focus on improving the functional and sensory properties of alternative protein sources and developing new processing technologies to optimize their use in dairy products. This review highlights the current status of alternative dairy proteins in cheese and yogurt, their functional properties, and the challenges of their use in these products.
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Affiliation(s)
- Martha L. Diaz-Bustamante
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Julia K. Keppler
- AFSG: Laboratory of Food Process Engineering, Wageningen University & Research, Wageningen, Netherlands
| | - Luis H. Reyes
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
| | - Oscar Alberto Alvarez Solano
- Grupo de Diseño de Productos y Procesos (GDPP), Department of Chemical and Food Engineering, Universidad de Los Andes, Bogotá, Colombia
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Kobayashi Y, El-Wali M, Guðmundsson H, Guðmundsdóttir EE, Friðjónsson ÓH, Karlsson EN, Roitto M, Tuomisto HL. Life-cycle assessment of yeast-based single-cell protein production with oat processing side-stream. Sci Total Environ 2023; 873:162318. [PMID: 36805067 DOI: 10.1016/j.scitotenv.2023.162318] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 02/13/2023] [Accepted: 02/14/2023] [Indexed: 06/18/2023]
Abstract
Production of fish meal and plant-based feed proteins continues to increase to meet the growing demand for seafood, leading to impacts on marine and terrestrial ecosystems. Microbial proteins such as single-cell proteins (SCPs) have been introduced as feed alternatives since they can replace current fish feed ingredients, e.g., soybean, which are associated with negative environmental impacts. Microbial protein production also enables utilization of grain processing side-streams as feedstock sources. This study assesses the environmental impacts of yeast-based SCP using oat side-stream as feedstock (OS-SCP). Life-cycle assessment with a cradle-to-gate approach was used to quantify global warming, freshwater eutrophication, marine eutrophication, terrestrial acidification, land use, and water consumption of OS-SCP production in Finland. Dried and wet side-streams of oat were compared with each other to identify differences in energy consumption and transportation effects. Sensitivity analysis was performed to examine the difference in impacts at various locations and fermentation times. Benchmarking was used to evaluate the environmental impacts of OS-SCP and other feed products, including both conventional and novel protein products. Results highlight the importance of energy sources in quantifying the environmental performance of OS-SCP production. OS-SCP produced with dried side-streams resulted in higher global warming (16.3 %) and water consumption (7.5 %) than OS-SCP produced from wet side-streams, reflecting the energy and water requirements for the drying process. Compared with conventional products, such as soy protein concentrates, OS-SCP resulted in 61 % less land use, while exacerbating the environmental impacts in all the other categories. OS-SCP had more impact on global warming (205-754 %), water consumption (166-1401 %), freshwater eutrophication (118-333 %), and terrestrial acidification (85-340 %) than other novel products, including yeast protein concentrate, methanotrophic bacterial SCP, and insect meal, while lowering global warming (11 %) and freshwater eutrophication (20 %) compared with dry microalgae biomass.
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Affiliation(s)
- Yumi Kobayashi
- Department of Agricultural Sciences, Faculty of Agriculture and Forestry, 27, 00014, University of Helsinki, Finland; Helsinki Institute of Sustainability Science (HELSUS), 4, 00014, University of Helsinki, Finland
| | - Mohammad El-Wali
- Department of Agricultural Sciences, Faculty of Agriculture and Forestry, 27, 00014, University of Helsinki, Finland; Helsinki Institute of Sustainability Science (HELSUS), 4, 00014, University of Helsinki, Finland.
| | | | | | | | | | - Marja Roitto
- Department of Agricultural Sciences, Faculty of Agriculture and Forestry, 27, 00014, University of Helsinki, Finland; Helsinki Institute of Sustainability Science (HELSUS), 4, 00014, University of Helsinki, Finland
| | - Hanna L Tuomisto
- Department of Agricultural Sciences, Faculty of Agriculture and Forestry, 27, 00014, University of Helsinki, Finland; Helsinki Institute of Sustainability Science (HELSUS), 4, 00014, University of Helsinki, Finland; Natural Resources Institute Finland, 2, 00790 Helsinki, Finland
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7
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Capson-Tojo G, Zuo Meng Gan A, Ledezma P, Batstone DJ, Hülsen T. Resource recovery using enriched purple phototrophic bacteria in an outdoor flat plate photobioreactor: Suspended vs. attached growth. Bioresour Technol 2023; 373:128709. [PMID: 36754239 DOI: 10.1016/j.biortech.2023.128709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
Purple phototrophic bacteria (PPB) can produce single-cell protein from wastewater at high yields. Growing in a biofilm vs suspended can improve product quality and consistency. This study compares suspended and attached growths of enriched PPB cultures in an outdoor flat plate photobioreactor treating poultry-processing wastewater. Attached growth had lower VFA removal efficiencies (95 ± 2.7 vs 84 ± 6.4 %) due to light limitations and low substrate diffusion rates. Nevertheless, similar overall treatment performances and productivities were achieved (16 ± 2.2 and 18 ± 2.4 gCOD·m-2·d-1 for attached and suspended) at loading rates of 1.2-1.5 gCOD·L-1·d-1. Biofilms had higher quality than suspended biomass, with lower ash contents (6.9(0.6)% vs 57(16)%) and higher PPB abundances (0.45-0.67 vs 0.30-0.45). The biofilm (20-50 % of the total biomass) might be used as feed and the suspended fraction as fertiliser, improving the economics of the process. Semi-continuous PPB growth outdoors as biofilm is technically feasible, obtaining a superior product without jeopardising performance.
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Affiliation(s)
- Gabriel Capson-Tojo
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, QLD 4072, Australia; CRETUS Institute, Department of Chemical Engineering, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Galicia, Spain; INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100 Narbonne, France.
| | - Albie Zuo Meng Gan
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Pablo Ledezma
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Damien J Batstone
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Tim Hülsen
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, QLD 4072, Australia; Fouling Doctors, Brisbane, QLD 4108, Australia
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Cardoso Alves S, Díaz-Ruiz E, Lisboa B, Sharma M, Mussatto SI, Thakur VK, Kalaskar DM, Gupta VK, Chandel AK. Microbial meat: A sustainable vegan protein source produced from agri-waste to feed the world. Food Res Int 2023; 166:112596. [PMID: 36914347 DOI: 10.1016/j.foodres.2023.112596] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 01/27/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023]
Abstract
In the modern world, animal and plant protein may not meet the sustainability criteria due to their high need for arable land and potable water consumption, among other practices. Considering the growing population and food shortage, finding alternative protein sources for human consumption is an urgent issue that needs to be solved, especially in developing countries. In this context, microbial bioconversion of valuable materials in nutritious microbial cells represent a sustainable alternative to the food chain. Microbial protein, also known as single-cell protein (SCP), consist of algae biomass, fungi or bacteria that are currently used as food source for both humans and animals. Besides contributing as a sustainable source of protein to feed the world, producing SCP, is important to reduce waste disposal problems and production costs meeting the sustainable development goals. However, for microbial protein as feed or food to become an important and sustainable alternative, addressing the challenges of raising awareness and achieving wider public regulatory acceptance is real and must be addressed with care and convenience. In this work, we critically reviewed the potential technologies for microbial protein production, its benefits, safety, and limitations associated with its uses, and perspectives for broader large-scale implementation. We argue that the information documented in this manuscript will assist in developing microbial meat as a major protein source for the vegan world.
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Affiliation(s)
- Samara Cardoso Alves
- Department of Biotechnology, Engineering School of Lorena, University of São Paulo, Lorena, São Paulo 12.602.810, Brazil
| | - Erick Díaz-Ruiz
- Department of Biotechnology, Engineering School of Lorena, University of São Paulo, Lorena, São Paulo 12.602.810, Brazil
| | - Bruna Lisboa
- Department of Biotechnology, Engineering School of Lorena, University of São Paulo, Lorena, São Paulo 12.602.810, Brazil
| | - Minaxi Sharma
- Haute Ecole Provinciale de Hainaut- Condorcet, 7800 ATH, Belgium
| | - Solange I Mussatto
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 223, 2800 Kongens Lyngby, Denmark
| | - Vijay Kumar Thakur
- Biorefining and Advanced Materials Research Center, Scotland's Rural College (SRUC), Kings Buildings, West Mains Road, Edinburgh, UK; School of Engineering, University of Petroleum & Energy Studies (UPES), Dehradun 248007, Uttarakhand, India
| | - Deepak M Kalaskar
- UCL Institute of orthopedics and Musculoskeletal Sciences (IOMS), Division of Surgery and Interventional Science, Royal National Orthopaedic Hospital-NHS Trust, Stanmore, Middlesex HA7 4LP, UK.
| | - Vijai Kumar Gupta
- Biorefining and Advanced Materials Research Center, Scotland's Rural College (SRUC), Kings Buildings, West Mains Road, Edinburgh, UK; Department of Biotechnology, Graphic Era Deemed to be University, Dehradun 248002, Uttarakhand, India.
| | - Anuj K Chandel
- Department of Biotechnology, Engineering School of Lorena, University of São Paulo, Lorena, São Paulo 12.602.810, Brazil.
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Muys M, González Cámara SJ, Derese S, Spiller M, Verliefde A, Vlaeminck SE. Dissolution rate and growth performance reveal struvite as a sustainable nutrient source to produce a diverse set of microbial protein. Sci Total Environ 2023; 866:161172. [PMID: 36572313 DOI: 10.1016/j.scitotenv.2022.161172] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/19/2022] [Accepted: 12/20/2022] [Indexed: 06/18/2023]
Abstract
To provide for the globally increasing demand for proteinaceous food, microbial protein (MP) has the potential to become an alternative food or feed source. Phosphorus (P), on the other hand, is a critical raw material whose global reserves are declining. Growing MP on recovered phosphorus, for instance, struvite obtained from wastewater treatment, is a promising MP production route that could supply protein-rich products while handling P scarcity. The aim of this study was to explore struvite dissolution kinetics in different MP media and characterize MP production with struvite as sole P-source. Different operational parameters, including pH, temperature, contact surface area, and ion concentrations were tested, and struvite dissolution rates were observed between 0.32 and 4.7 g P/L/d and a solubility between 0.23 and 2.22 g P-based struvite/L. Growth rates and protein production of the microalgae Chlorella vulgaris and Limnospira sp. (previously known as Arthrospira sp.), and the purple non‑sulfur bacterium Rhodopseudomonas palustris on struvite were equal to or higher than growth on conventional potassium phosphate. For aerobic heterotrophic bacteria, two slow-growing communities showed decreased growth on struvite, while the growth was increased for a third fast-growing one. Furthermore, MP protein content on struvite was always comparable to the one obtained when grown on standard media. Together with the low content in metals and micropollutants, these results demonstrate that struvite can be directly applied as an effective nutrient source to produce fast-growing MP, without any previous dissolution step. Combining a high purity recovered product with an efficient way of producing protein results in a strong environmental win-win.
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Affiliation(s)
- Maarten Muys
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - Sergio J González Cámara
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - Sebastiaan Derese
- Research Group of Particle and Interfacial Technology, Department of Applied Analytical and Physical Chemistry, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Marc Spiller
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium; Centre for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Frieda Saeysstraat 1, 9052 Ghent, Belgium
| | - Arne Verliefde
- Research Group of Particle and Interfacial Technology, Department of Applied Analytical and Physical Chemistry, Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Centre for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Frieda Saeysstraat 1, 9052 Ghent, Belgium
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium; Centre for Advanced Process Technology for Urban Resource Recovery (CAPTURE), Frieda Saeysstraat 1, 9052 Ghent, Belgium.
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10
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Tian Y, Li J, Meng J, Li J. High-yield production of single-cell protein from starch processing wastewater using co-cultivation of yeasts. Bioresour Technol 2023; 370:128527. [PMID: 36572157 DOI: 10.1016/j.biortech.2022.128527] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 12/20/2022] [Accepted: 12/21/2022] [Indexed: 06/17/2023]
Abstract
Single-cell protein (SCP) from potato starch processing wastewater (PSPW) shows great potential against protein scarcity and unsustainable production of plant and animal proteins. In this study, five yeasts were selected to conduct a series of PSPW fermentation for obtaining high-value SCP by optimizing fermentation conditions. The yeast combination was optimized as Candida utilis, Geotrichum candidum and Candida tropicalis with the volume proportion of 9:5:1. The inoculum size, temperature, rotation speed and initial pH were optimized at 12 %, 24℃, 200 r·min-1 and ∼ 4.13 (natural pH), respectively. At the optimal conditions, SCP yield of 3.06 g·L-1 and water-soluble protein of 17.32 % were obtained with the chemical oxygen demand removal of 56.9 %. A resource-recycling process of PSPW was proposed by coupling yeast fermentation and up-flow anaerobic sludge blanket (UASB) treatment to achieve simultaneous high-level organic removal and SCP production, which could be a promising alternative technology for PSPW treatment.
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Affiliation(s)
- Yajie Tian
- National-Local Joint Engineering Research Center for Biomass Energy Development and Utilization, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, PR China
| | - Jianzheng Li
- National-Local Joint Engineering Research Center for Biomass Energy Development and Utilization, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, PR China
| | - Jia Meng
- National-Local Joint Engineering Research Center for Biomass Energy Development and Utilization, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, PR China.
| | - Jiuling Li
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland 4072, Australia
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11
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Papini G, Muys M, Van Winckel T, Meerburg FA, Van Beeck W, Vermeir P, Vlaeminck SE. Boosting aerobic microbial protein productivity and quality on brewery wastewater: Impact of anaerobic acidification, high-rate process and biomass age. Bioresour Technol 2023; 368:128285. [PMID: 36368491 DOI: 10.1016/j.biortech.2022.128285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 11/01/2022] [Accepted: 11/02/2022] [Indexed: 06/16/2023]
Abstract
Consortia of aerobic heterotrophic bacteria (AHB) are appealing as sustainable alternative protein ingredient for aquaculture given their high nutritional qualities, and their production potential on feed-grade industrial wastewater. Today, the impacts of pre-treatment, bioprocess choice and key parameter settings on AHB productivity and nutritional properties are unknown. This study investigated for the first time AHB microbial protein production effects based on (i) raw vs anaerobically fermented brewery wastewater, (ii) high-rate activated sludge (HRAS) without vs with feast-famine conditions, and (iii) three short solid retention time (SRT): 0.25, 0.50 and 1.00 d. High biomass (4.4-8.0 g TSS/L/d) and protein productivities (1.9-3.2 g protein/L/d) were obtained while achieving COD removal efficiencies up to 98 % at SRT 0.50 d. The AHB essential amino acid (EAA) profiles were above rainbow trout requirements, excluding the S-containing EAA, highlighting the AHB biomass replacement potential for unsustainable fishmeal in salmonid diets.
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Affiliation(s)
- Gustavo Papini
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Maarten Muys
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Tim Van Winckel
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | | | - Wannes Van Beeck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Pieter Vermeir
- Laboratory of Chemical Analysis, Department of Green Chemistry and Technology, Ghent University, Valentin Vaerwyckweg 1, 9000 Ghent, Belgium
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium.
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12
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Spanoghe J, Ost KJ, Van Beeck W, Vermeir P, Lebeer S, Vlaeminck SE. Purple bacteria screening for photoautohydrogenotrophic food production: Are new H(2)-fed isolates faster and nutritionally better than photoheterotrophically obtained reference species? N Biotechnol 2022; 72:38-47. [PMID: 36049649 DOI: 10.1016/j.nbt.2022.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/26/2022] [Accepted: 08/28/2022] [Indexed: 12/14/2022]
Abstract
Photoautohydrogenotrophic enrichments of wastewater treatment microbiomes were performed to obtain hypothetically high-potential specialist species for biotechnological applications. From these enrichment cultures, ten photoautohydrogenotrophic species were isolated: six Rhodopseudomonas species, three Rubrivivax members and Rhodobacter blasticus. The performance of these isolates was compared to three commonly studied, and originally photoheterotrophically enriched species (Rhodopseudomonas palustris, Rhodobacter capsulatus and Rhodobacter sphaeroides), designated as reference species. Repeated subcultivations were applied to improve the initial poor performance of the isolates (acclimation effect), which resulted in increases in both maximum growth rate and protein productivity. However, the maximum growth rate of the reference species remained 3-7 times higher compared to the isolates (0.42-0.84 d-1 at 28 °C), while protein productivities remained 1.5-1.7 times higher. This indicated that H2-based enrichment did not result in photoautohydrogenotrophic specialists, suggesting that the reference species are more suitable for intensified biomass and protein production. On the other hand, the isolates were able to provide equally high protein quality profiles as the references species, providing full dietary essential amino acid matches for human food. Lastly, the effect of metabolic carbon/electron switching (back and forth between auto- to heterotrophic conditions) initially boosted µmax when returning to photoautohydrogenotrophic conditions. However, the switch negatively impacted lag phase, protein productivities and pigment contents. In the case of protein productivity, the acquired acclimation was partially lost with decreases of up to 44 % and 40 % respectively for isolates and reference species. Finally, the three reference species, and specifically Rh. capsulatus, remained the most suitable candidate(s) for further biotechnological development.
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13
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Yang R, Chen Z, Hu P, Zhang S, Luo G. Two-stage fermentation enhanced single-cell protein production by Yarrowia lipolytica from food waste. Bioresour Technol 2022; 361:127677. [PMID: 35878768 DOI: 10.1016/j.biortech.2022.127677] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
The resource utilization of food waste is crucial, and single-cell protein (SCP) is attracting much attention due to its high value. This study aimed to convert food waste to SCP by Yarrowia lipolytica. It was found the chemical oxygen demand (COD) removal rate 77 ± 1.70% was achieved at 30 g COD/L with the protein content of biomass only 24.1 ± 0.4% w/w biomass dry weight (BDW) in one-stage fermentation system. However, the protein content was significantly increased to 38.8 ± 0.2% w/w BDW with the COD removal rate 85.5 ± 0.7% by a two-stage fermentation process, where the food waste was firstly anaerobically fermented to volatile fatty acids and then converted to SCP with Yarrowia lipolytica. Transcriptomic analysis showed that the expression of SCP-producing genes including ATP citrate (pro-S)-lyase and fumarate hydratase class II were up-regulated in the two-stage transformation, resulting in more organic degradation for SCP synthesis.
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Affiliation(s)
- Rui Yang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai 200438, China
| | - Zheng Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai 200438, China
| | - Peng Hu
- Shanghai GTL Biotech Co., Ltd., 1688 North Guoquan Road, Shanghai 200438, China
| | - Shicheng Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai 200438, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Gang Luo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Technical Service Platform for Pollution Control and Resource Utilization of Organic Wastes, Shanghai 200438, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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14
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Abstract
This chapter reviews the uses of processed fungal cells as protein-rich foods in substitution to meat. Yeasts, mushrooms, and filamentous fungi have long been part of the human diet, improving the nutritional quality and taste of different foods. Recently, because of the populational growth and environmental impact caused by animal farming, the use of animal-derived protein has been raising concerns in public and scientific debates. Fungal biomass represents a nutritious, safe meat alternative that can help society in the reduction of greenhouse gases emissions and improve public health. Additionally, it provides all essential amino acids and has an interesting fatty acid profile. Current research is involved in finding new strains with improved efficiency, the investigation of new substrates (especially agro-industrial wastes) to reduce the environmental impact, and the development of new formulations to use mycoprotein in different dishes.
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Affiliation(s)
- Pedro F Souza Filho
- Laboratory of Biochemical Engineering, Chemical Engineering Department, Federal University of Rio Grande do Norte (UFRN), Natal, RN, Brazil.
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15
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Tong S, Zhao L, Zhu D, Chen W, Chen L, Li D. From formic acid to single-cell protein: genome-scale revealing the metabolic network of Paracoccus communis MA5. BIORESOUR BIOPROCESS 2022; 9:55. [PMID: 38647589 PMCID: PMC10992362 DOI: 10.1186/s40643-022-00544-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 04/29/2022] [Indexed: 11/10/2022] Open
Abstract
With the increase in population growth and environmental pollution, the daily protein supply is facing great challenges. Single-cell protein (SCP) produced by microorganism fermentation is a good alternative for substituting plant- and animal-derived proteins. In this study, Paracoccus communis MA5 isolated from soil previously demonstrated an excellent ability to synthesize SCP directly from sodium formate. To investigate the central metabolic network of formic acid assimilation and protein synthesis, genome-scale analyses were performed. Genomic analysis showed that complete tetrahydrofolate cycle-, serine cycle-, glycolytic pathway-, tricarboxylic acid (TCA) cycle- and nitrogen metabolism-relevant genes were annotated in the genome. These pathways play key roles in the conversion of formic acid into proteins. Transcriptional analysis showed that sodium formate stress could stimulate the metabolic pathway in response to environmental stress, but weaken the sulfur metabolic pathway to inhibit amino acid synthesis, resulting in a decrease in protein content (30% vs 44%). However, under culture conditions with ammonium sulfate, metabolic pathways associated with protein synthesis were accelerated, causing an increase in protein content (53% vs 44%); while the tetrahydrofolate cycle associated with formic acid assimilation was inhibited, causing a 62.5% decrease in growth rate (OD600: 0.21 vs 0.56). These results provide evidence of protein synthesis from sodium formate in strain MA5 at the gene level and lay a theoretical foundation for the optimization of fermentation systems using formic acid as a carbon source.
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Affiliation(s)
- Sheng Tong
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Innovation Centre for Synthetic Biology, Tianjin, 300308, China
| | - Lizhi Zhao
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-Utilization, Tianjin University of Sciences and Technology, Tianjin, 300457, China
| | - Daling Zhu
- Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-Utilization, Tianjin University of Sciences and Technology, Tianjin, 300457, China
| | - Wuxi Chen
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Innovation Centre for Synthetic Biology, Tianjin, 300308, China
| | - Limei Chen
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China
- National Innovation Centre for Synthetic Biology, Tianjin, 300308, China
| | - Demao Li
- Tianjin Key Laboratory for Industrial Biological Systems and Bioprocessing Engineering, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308, China.
- National Innovation Centre for Synthetic Biology, Tianjin, 300308, China.
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16
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Najari Z, Khodaiyan F, Yarmand MS, Hosseini SS. Almond hulls waste valorization towards sustainable agricultural development: Production of pectin, phenolics, pullulan, and single cell protein. Waste Manag 2022; 141:208-219. [PMID: 35149477 DOI: 10.1016/j.wasman.2022.01.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 12/16/2021] [Accepted: 01/09/2022] [Indexed: 06/14/2023]
Abstract
This research aimed to valorize almond hulls based on a zero-waste strategy towards sustainable agricultural developments for the recovery and production of valuable compounds. For this purpose, the potential to produce four products, including pectin (AHP), phenolic compounds (AHPC), pullulan (PUL), and single-cell protein (SCP), was examined. The acidic extraction factors were optimized using a Box-Behnken design for the simultaneous extraction of AHP and AHPC, and the obtained results showed that the maximum AHP (26.32% w/w) and AHPC (6.97% w/w) yields were achieved at 90 °C, pH of 1.4, 58.65 min, and liquid-solid ratio (LSR) of 20.13 v/w as the optimum point. In the next step, the solid residues that remained from the AHP and AHPC extraction process (PESR) were treated with cellulase enzyme and ultrasound and were used for simultaneous microbial production of PUL (34.29-24.56 g/L) and biomass containing SCP (19.31-13.44% w/w). Furthermore, the obtained results showed that AHP was low methylated (26.40%), rich in galacturonic acid (67.88%), and high in molecular weight (595.299 kDa). Also, the investigations of structural properties of AHP and PUL confirmed the presence of chemical structures of these polysaccharides in the formed supernatants. In addition, the AHPC showed considerable antioxidant activity compared with ascorbic acid (ASC) and BHA.
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Affiliation(s)
- Zahra Najari
- Bioprocessing and Biodetection Laboratory, Department of Food Science and Engineering, University of Tehran, Karaj 31587-77871, Iran
| | - Faramarz Khodaiyan
- Bioprocessing and Biodetection Laboratory, Department of Food Science and Engineering, University of Tehran, Karaj 31587-77871, Iran.
| | - Mohammad Saeid Yarmand
- Bioprocessing and Biodetection Laboratory, Department of Food Science and Engineering, University of Tehran, Karaj 31587-77871, Iran
| | - Seyed Saeid Hosseini
- Bioprocessing and Biodetection Laboratory, Department of Food Science and Engineering, University of Tehran, Karaj 31587-77871, Iran
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17
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Gu Y, Hu Y, Huang C, Lai C, Ling Z, Yong Q. Co-production of amino acid-rich xylooligosaccharide and single-cell protein from paper mulberry by autohydrolysis and fermentation technologies. Biotechnol Biofuels Bioprod 2022; 15:1. [PMID: 35418087 PMCID: PMC8746646 DOI: 10.1186/s13068-021-02095-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 12/18/2021] [Indexed: 11/10/2022]
Abstract
Background Autohydrolysis is an extensively investigated pretreatment method due to its environmental friendliness. During autohydrolysis, most xylan from hemicellulose can be converted into xylooligosaccharides (XOS), and cellulose in the autohydrolyzed residues can be transformed into glucose after enzymatic hydrolysis. Both of these are value-added biochemicals in the biorefining process. In this work, paper mulberry (PM), which contains abundant protein, was utilized as a raw material to coproduce XOS and single-cell protein (SCP) through autohydrolysis and fermentation technologies. Results The results showed that 8.3 g of XOS and 1.8 g of amino acids could be recovered in the autohydrolysate (based on 100 g raw material) after autohydrolysis (170 °C, 1 h). Moreover, 5.7 g of low-DP XOS along with 1.8 g of amino acids could be further obtained from the autohydrolysate after hydrolysis with endo-β-1-4-xylanase. In addition, 20.1 g of fermentable monosaccharides was recovered after hydrolyzing the autohydrolyzed PM with cellulase, which can be used to produce 4.8 g of SCP after fermentation with Candida utilis. Conclusion As a valuable application of PM, a novel process is proposed to coproduce amino acid-rich XOS and SCP through autohydrolysis. The carbohydrate of PM is effectively converted to high value-added products.
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Affiliation(s)
- Yang Gu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Yingying Hu
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Caoxing Huang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Chenhuan Lai
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Zhe Ling
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China.,State Key Laboratory of Pulp Paper Engineering, South China University of Technology, Guangzhou, 510640, China
| | - Qiang Yong
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China.
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18
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Spanoghe J, Vermeir P, Vlaeminck SE. Microbial food from light, carbon dioxide and hydrogen gas: Kinetic, stoichiometric and nutritional potential of three purple bacteria. Bioresour Technol 2021; 337:125364. [PMID: 34120062 DOI: 10.1016/j.biortech.2021.125364] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/28/2021] [Accepted: 05/29/2021] [Indexed: 06/12/2023]
Abstract
The urgency for a protein transition towards more sustainable solutions is one of the major societal challenges. Microbial protein is one of the alternative routes, in which land- and fossil-free production should be targeted. The photohydrogenotrophic growth of purple bacteria, which builds on the H2- and CO2-economy, is unexplored for its microbial protein potential. The three tested species (Rhodobacter capsulatus, Rhodobacter sphaeroides and Rhodopseudomonas palustris) obtained promising growth rates (2.3-2.7 d-1 at 28°C) and protein productivities (0.09-0.12 g protein L-1 d-1), rendering them likely faster and more productive than microalgae. The achieved protein yields (2.6-2.9 g protein g-1 H2) transcended the ones of aerobic hydrogen oxidizing bacteria. Furthermore, all species provided full dietary protein matches for humans and their fatty acid content was dominated by vaccenic acid (82-86%). Given its kinetic and nutritional performance we recommend to consider Rhodobacter capsulatus as a high-potential sustainable source of microbial food.
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Affiliation(s)
- Janne Spanoghe
- Research Group of Sustainable Energy, Air and Water Technology (DuEL), Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, Antwerpen 2020, Belgium
| | - Pieter Vermeir
- Laboratory for Chemical Analysis, Department of Green Chemistry and Technology, Ghent University, Valentin Vaerwyckweg 1, Gent 9000, Belgium
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology (DuEL), Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, Antwerpen 2020, Belgium.
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19
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Alloul A, Muys M, Hertoghs N, Kerckhof FM, Vlaeminck SE. Cocultivating aerobic heterotrophs and purple bacteria for microbial protein in sequential photo- and chemotrophic reactors. Bioresour Technol 2021; 319:124192. [PMID: 33039841 DOI: 10.1016/j.biortech.2020.124192] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/24/2020] [Accepted: 09/25/2020] [Indexed: 06/11/2023]
Abstract
Aerobic heterotrophic bacteria (AHB) and purple non-sulfur bacteria (PNSB) are typically explored as two separate types of microbial protein, yet their properties as respectively a bulk and added-value feed ingredient make them appealing for combined use. The feasibility of cocultivation in a sequential photo- and chemotrophic approach was investigated. First, mapping the chemotrophic growth kinetics for four Rhodobacter, Rhodopseudomonas and Rhodospirillum species on different carbon sources showed a preference for fructose (µmax 2.4-3.9 d-1 28 °C; protein 36-59%DW). Secondly, a continuous photobioreactor inoculated with Rhodobacter capsulatus (VFA as C-source) delivered the starter culture for an aerobic batch reactor (fructose as C-source). This two-stage system showed an improved nutritional quality compared to AHB production: higher protein content (45-71%DW), more attractive amino/fatty acid profile and contained up to 10% PNSB. The findings strengthen protein production with cocultures and might enable the implementation of the technology for resource recovery on streams such as wastewater.
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Affiliation(s)
- Abbas Alloul
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Maarten Muys
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Nick Hertoghs
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Frederiek-Maarten Kerckhof
- Center for Microbial Ecology and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000 Gent, Belgium
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium.
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20
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Bianco A, Budroni M, Zara S, Mannazzu I, Fancello F, Zara G. The role of microorganisms on biotransformation of brewers' spent grain. Appl Microbiol Biotechnol 2020; 104:8661-8678. [PMID: 32875363 PMCID: PMC7502439 DOI: 10.1007/s00253-020-10843-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/07/2020] [Accepted: 08/17/2020] [Indexed: 01/11/2023]
Abstract
Brewers' spent grain (BSG) is the most abundant by-product of brewing. Due to its microbiological instability and high perishability, fresh BSG is currently disposed of as low-cost cattle feed. However, BSG is an appealing source of nutrients to obtain products with high added value through microbial-based transformation. As such, BSG could become a potential source of income for the brewery itself. While recent studies have covered the relevance of BSG chemical composition in detail, this review aims to underline the importance of microorganisms from the stabilization/contamination of fresh BSG to its biotechnological exploitation. Indeed, the evaluation of BSG-associated microorganisms, which include yeast, fungi, and bacteria, can allow their safe use and the best methods for their exploitation. This bibliographical examination is particularly focused on the role of microorganisms in BSG exploitation to (1) produce enzymes and metabolites of industrial interest, (2) supplement human and animal diets, and (3) improve soil fertility. Emerging safety issues in the use of BSG as a food and feed additive is also considered, particularly considering the presence of mycotoxins.Key points• Microorganisms are used to enhance brewers' spent grain nutritional value.• Knowledge of brewers' spent grain microbiota allows the reduction of health risks. Graphical abstract.
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Affiliation(s)
- Angela Bianco
- Department of Agricultural Science, University of Sassari, Sassari, Italy
| | - Marilena Budroni
- Department of Agricultural Science, University of Sassari, Sassari, Italy.
| | - Severino Zara
- Department of Agricultural Science, University of Sassari, Sassari, Italy
| | - Ilaria Mannazzu
- Department of Agricultural Science, University of Sassari, Sassari, Italy
| | - Francesco Fancello
- Department of Agricultural Science, University of Sassari, Sassari, Italy
| | - Giacomo Zara
- Department of Agricultural Science, University of Sassari, Sassari, Italy
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21
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Capson-Tojo G, Batstone DJ, Grassino M, Vlaeminck SE, Puyol D, Verstraete W, Kleerebezem R, Oehmen A, Ghimire A, Pikaar I, Lema JM, Hülsen T. Purple phototrophic bacteria for resource recovery: Challenges and opportunities. Biotechnol Adv 2020; 43:107567. [PMID: 32470594 DOI: 10.1016/j.biotechadv.2020.107567] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/11/2020] [Accepted: 05/14/2020] [Indexed: 10/24/2022]
Abstract
Sustainable development is driving a rapid focus shift in the wastewater and organic waste treatment sectors, from a "removal and disposal" approach towards the recovery and reuse of water, energy and materials (e.g. carbon or nutrients). Purple phototrophic bacteria (PPB) are receiving increasing attention due to their capability of growing photoheterotrophically under anaerobic conditions. Using light as energy source, PPB can simultaneously assimilate carbon and nutrients at high efficiencies (with biomass yields close to unity (1 g CODbiomass·g CODremoved-1)), facilitating the maximum recovery of these resources as different value-added products. The effective use of infrared light enables selective PPB enrichment in non-sterile conditions, without competition with other phototrophs such as microalgae if ultraviolet-visible wavelengths are filtered. This review reunites results systematically gathered from over 177 scientific articles, aiming at producing generalized conclusions. The most critical aspects of PPB-based production and valorisation processes are addressed, including: (i) the identification of the main challenges and potentials of different growth strategies, (ii) a critical analysis of the production of value-added compounds, (iii) a comparison of the different value-added products, (iv) insights into the general challenges and opportunities and (v) recommendations for future research and development towards practical implementation. To date, most of the work has not been executed under real-life conditions, relevant for full-scale application. With the savings in wastewater discharge due to removal of organics, nitrogen and phosphorus as an important economic driver, priorities must go to using PPB-enriched cultures and real waste matrices. The costs associated with artificial illumination, followed by centrifugal harvesting/dewatering and drying, are estimated to be 1.9, 0.3-2.2 and 0.1-0.3 $·kgdry biomass-1. At present, these costs are likely to exceed revenues. Future research efforts must be carried out outdoors, using sunlight as energy source. The growth of bulk biomass on relatively clean wastewater streams (e.g. from food processing) and its utilization as a protein-rich feed (e.g. to replace fishmeal, 1.5-2.0 $·kg-1) appears as a promising valorisation route.
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Affiliation(s)
- Gabriel Capson-Tojo
- Advanced Water Management Centre, The University of Queensland, Brisbane, QLD 4072, Australia; CRETUS Institute, Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
| | - Damien J Batstone
- Advanced Water Management Centre, The University of Queensland, Brisbane, QLD 4072, Australia.
| | - María Grassino
- Advanced Water Management Centre, The University of Queensland, Brisbane, QLD 4072, Australia.
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium.
| | - Daniel Puyol
- Department of Chemical and Environmental Technology, ESCET, Rey Juan Carlos University, Móstoles, Spain.
| | - Willy Verstraete
- Center for Microbial Ecology and Technology (CMET), Ghent University, Coupure Links 653, 9000 Gent, Belgium; Avecom NV, Industrieweg 122P, 9032 Wondelgem, Belgium.
| | - Robbert Kleerebezem
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, the Netherlands.
| | - Adrian Oehmen
- School of Chemical Engineering, The University of Queensland, Brisbane, QLD 4072, Australia.
| | - Anish Ghimire
- Department of Environmental Science and Engineering, Kathmandu University, Dhulikhel, Nepal.
| | - Ilje Pikaar
- School of Civil Engineering, The University of Queensland, Brisbane, QLD 4072, Australia.
| | - Juan M Lema
- CRETUS Institute, Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
| | - Tim Hülsen
- Advanced Water Management Centre, The University of Queensland, Brisbane, QLD 4072, Australia.
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22
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Spiller M, Muys M, Papini G, Sakarika M, Buyle M, Vlaeminck SE. Environmental impact of microbial protein from potato wastewater as feed ingredient: Comparative consequential life cycle assessment of three production systems and soybean meal. Water Res 2020; 171:115406. [PMID: 31881500 DOI: 10.1016/j.watres.2019.115406] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 11/14/2019] [Accepted: 12/17/2019] [Indexed: 06/10/2023]
Abstract
Livestock production is utilizing large amounts of protein-rich feed ingredients such as soybean meal. The proven negative environmental impacts of soybean meal production incentivize the search for alternative protein sources. One promising alternative is Microbial Protein (MP), i.e. dried microbial biomass. To date, only few life cycle assessments (LCAs) for MP have been carried out, none of which has used a consequential modelling approach nor has been investigating the production of MP on food and beverage wastewater. Therefore, the objective of this study is to evaluate the environmental impact of MP production on a food and beverage effluent as a substitute for soybean meal using a consequential modelling approach. Three different types of MP production were analysed, namely consortia containing Aerobic Heterotrophic Bacteria (AHB), Microalgae and AHB (MaB), and Purple Non-Sulfur Bacteria (PNSB). The production of MP was modelled for high-strength potato wastewater (COD = 10 kg/m3) at a flow rate of 1,000 m3/day. LCA results were compared against soybean meal production for the endpoint impact categories human health, ecosystems, and resources. Soybean meal showed up to 52% higher impact on human health and up to 87% higher impact on ecosystems than MP. However, energy-related aspects resulted in an 8-88% higher resource exploitation for MP. A comparison between the MP production systems showed that MaB performed best when considering ecosystems (between 13 and 14% better) and resource (between 71 and 80% better) impact categories, while AHB and PNSB had lower values for the impact category human health (8-12%). The sensitivity analysis suggests that the conclusions drawn are robust as in the majority of 1,000 Monte Carlo runs the initial results are confirmed. In conclusion, it is suggested that MP is an alternative protein source of comparatively low environmental impact that should play a role in the future protein transition, in particular when further process improvements can be implemented and more renewable or waste energy sources will be used.
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Affiliation(s)
- Marc Spiller
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium.
| | - Maarten Muys
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
| | - Gustavo Papini
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
| | - Myrsini Sakarika
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
| | - Matthias Buyle
- Energy and Materials in Infrastructure and Buildings EMIB, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium; Sustainable Materials Management, Flemish Institute for Technological Research (VITO), Boeretang 200, 2400, Mol, Belgium
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
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23
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Lapeña D, Olsen PM, Arntzen MØ, Kosa G, Passoth V, Eijsink VGH, Horn SJ. Spruce sugars and poultry hydrolysate as growth medium in repeated fed-batch fermentation processes for production of yeast biomass. Bioprocess Biosyst Eng 2019; 43:723-736. [PMID: 31883034 PMCID: PMC7064453 DOI: 10.1007/s00449-019-02271-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 12/13/2019] [Indexed: 02/07/2023]
Abstract
The production of microbial protein in the form of yeast grown on lignocellulosic sugars and nitrogen-rich industrial residues is an attractive approach for reducing dependency on animal and plant protein. Growth media composed of enzymatically saccharified sulfite-pulped spruce wood, enzymatic hydrolysates of poultry by-products and urea were used for the production of single-cell protein. Strains of three different yeast species, Cyberlindnera jadinii, Wickerhamomyces anomalus and Blastobotrys adeninivorans, were cultivated aerobically using repeated fed-batch fermentation up to 25 L scale. Wickerhamomyces anomalus was the most efficient yeast with yields of 0.6 g of cell dry weight and 0.3 g of protein per gram of glucose, with cell and protein productivities of 3.92 g/L/h and 1.87 g/L/h, respectively. Using the conditions developed here for producing W. anomalus, it would take 25 industrial (200 m3) continuously operated fermenters to replace 10% of the fish feed protein used in Norway.
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Affiliation(s)
- David Lapeña
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432, Ås, Norway
| | - Pernille M Olsen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432, Ås, Norway
| | - Magnus Ø Arntzen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432, Ås, Norway
| | - Gergely Kosa
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432, Ås, Norway
| | - Volkmar Passoth
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, P.O. Box 7015, S-75007, Uppsala, Sweden
| | - Vincent G H Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432, Ås, Norway
| | - Svein J Horn
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O. Box 5003, N-1432, Ås, Norway.
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24
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Sui Y, Muys M, Van de Waal DB, D'Adamo S, Vermeir P, Fernandes TV, Vlaeminck SE. Enhancement of co-production of nutritional protein and carotenoids in Dunaliella salina using a two-phase cultivation assisted by nitrogen level and light intensity. Bioresour Technol 2019; 287:121398. [PMID: 31078812 DOI: 10.1016/j.biortech.2019.121398] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/26/2019] [Accepted: 04/28/2019] [Indexed: 05/06/2023]
Abstract
Microalga Dunaliella salina is known for its carotenogenesis. At the same time, it can also produce high-quality protein. The optimal conditions for D. salina to co-produce intracellular pools of both compounds, however, are yet unknown. This study investigated a two-phase cultivation strategy to optimize combined high-quality protein and carotenoid production of D. salina. In phase-one, a gradient of nitrogen concentrations was tested. In phase-two, effects of nitrogen pulse and high illumination were tested. Results reveal optimized protein quantity, quality (expressed as essential amino acid index EAAI) and carotenoids content in a two-phase cultivation, where short nitrogen starvation in phase-one was followed by high illumination during phase-two. Adopting this strategy, productivities of protein, EAA and carotenoids reached 22, 7 and 3 mg/L/d, respectively, with an EAAI of 1.1. The quality of this biomass surpasses FAO/WHO standard for human nutrition, and the observed level of β-carotene presents high antioxidant pro-vitamin A activity.
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Affiliation(s)
- Yixing Sui
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Maarten Muys
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Dedmer B Van de Waal
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), PO Box 50, 6700 AB Wageningen, The Netherlands
| | - Sarah D'Adamo
- Bioprocess Engineering, Wageningen University & Research, PO Box 16, 6700 AA, Wageningen, The Netherlands
| | - Pieter Vermeir
- Laboratory of Chemical Analysis, Department of Green Chemistry and Technology, Ghent University, Valentin Vaerwyckweg 1, 9000 Gent, Belgium
| | - Tânia V Fernandes
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), PO Box 50, 6700 AB Wageningen, The Netherlands
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium.
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25
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Alloul A, Wuyts S, Lebeer S, Vlaeminck SE. Volatile fatty acids impacting phototrophic growth kinetics of purple bacteria: Paving the way for protein production on fermented wastewater. Water Res 2019; 152:138-147. [PMID: 30665160 DOI: 10.1016/j.watres.2018.12.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 12/02/2018] [Accepted: 12/21/2018] [Indexed: 06/09/2023]
Abstract
Nutrient losses in our food chain severely surpass our planetary boundaries. Resource recovery can contribute to mitigation, for instance through converting wastewater resources to microbial protein for animal feed. Wastewater typically holds a complex mixture of organics, posing a challenge to selectively produce heterotrophic biomass. Ensuring the product's quality could be achieved by anaerobic generation of volatile fatty acids (VFAs) followed by photoheterotrophic production of purple non-sulfur bacteria (PNSB) with infrared light. This study aimed to determine the most suitable PNSB culture for VFA conversion and map the effect of acetate, propionate, butyrate and a VFA mixture on growth and biomass yield. Six cultures were screened in batch: (i) Rhodopseudomonas palustris, (ii) Rhodobacter sphaeroides, (iii) Rhodospirillum rubrum, (iv) a 3-species synthetic community (i+ii+iii), (v) a community enriched on VFA holding Rb. capsulatus, and (vi) Rb. capsulatus (isolate 'v'). The VFA mixture elevated growth rates with a factor 1.3-2.5 compared to individual VFA. Rb. capsulatus showed the highest growth rates: 1.8-2.2 d-1 (enriched) and 2.3-3.8 d-1 (isolated). In a photobioreactor (PBR) inoculated with the Rb. capsulatus enrichment, decreasing sludge retention time (SRT) yielded lower biomass concentrations, yet increased productivities, reaching 1.7 g dry weight (DW) L-1 d-1, the highest phototrophic rate reported thus far, and a growth rate of up to 5 d-1. PNSB represented 26-57% of the community and the diversity index was low (3-7), with a dominance of Rhodopseudomonas at long SRT and Rhodobacter at short SRT. The biomass yield for all cultures, in batch and reactor cultivation, approached 1 g CODBiomass g-1 CODRemoved. An economic estimation for a two-stage approach on brewery wastewater (load 2427 kg COD d-1) showed that 0.5 d SRT allowed for the lowest production cost (€ 10 kg-1 DW; equal shares for capex and opex). The findings strengthen the potential for a novel two-stage approach for resource recovery from industrial wastewater, enabling high-rate PNSB production.
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Affiliation(s)
- Abbas Alloul
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
| | - Sander Wuyts
- Research Group of Environmental Ecology & Microbiology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
| | - Sarah Lebeer
- Research Group of Environmental Ecology & Microbiology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerpen, Belgium.
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26
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Sui Y, Muys M, Vermeir P, D'Adamo S, Vlaeminck SE. Light regime and growth phase affect the microalgal production of protein quantity and quality with Dunaliella salina. Bioresour Technol 2019; 275:145-152. [PMID: 30583115 DOI: 10.1016/j.biortech.2018.12.046] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 12/13/2018] [Accepted: 12/14/2018] [Indexed: 06/09/2023]
Abstract
The microalga Dunaliella salina has been widely studied for carotenogenesis, yet its protein production for human nutrition has rarely been reported. This study unveils the effects of growth phase and light regime on protein and essential amino acid (EAA) levels in D. salina. Cultivation under 24-h continuous light was compared to 12-h/12-h light/dark cycle. The essential amino acid index (EAAI) of D. salina showed accumulating trends up to 1.53 in the stationary phase, surpassing FAO/WHO standard for human nutrition. Light/dark conditions inferred a higher light-usage efficiency, yielding 5-97% higher protein and 18-28% higher EAA mass on light energy throughout the growth, accompanied by 138% faster growth during the light phase of the light/dark cycle, compared to continuous light. The findings revealed D. salina to be especially suitable for high-quality protein production, particularly grown under light/dark conditions, with nitrogen limitation as possible trigger, and harvested in the stationary phase.
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Affiliation(s)
- Yixing Sui
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Maarten Muys
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Pieter Vermeir
- Laboratory of Chemical Analysis, Department of Green Chemistry and Technology, Gent University, Valentin Vaerwyckweg 1, 9000 Gent, Belgium
| | - Sarah D'Adamo
- Bioprocess Engineering, Wageningen University & Research, PO Box 16, 6700 AA, Wageningen, The Netherlands
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium.
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27
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Wu J, Hu J, Zhao S, He M, Hu G, Ge X, Peng N. Single-cell Protein and Xylitol Production by a Novel Yeast Strain Candida intermedia FL023 from Lignocellulosic Hydrolysates and Xylose. Appl Biochem Biotechnol 2018; 185:163-78. [PMID: 29098561 DOI: 10.1007/s12010-017-2644-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 10/19/2017] [Indexed: 11/06/2022]
Abstract
Yeasts are good candidates to utilize the hydrolysates of lignocellulose, the most abundant bioresource, for bioproducts. This study aimed to evaluate the efficiencies of single-cell protein (SCP) and xylitol production by a novel yeast strain, Candida intermedia FL023, from lignocellulosic hydrolysates and xylose. This strain efficiently assimilated hexose, pentose, and cellubiose for cell mass production with the crude protein content of 484.2 g kg−1 dry cell mass. SCP was produced by strain FL023 using corncob hydrolysate and urea as the carbon and nitrogen sources with the dry cell mass productivity 0.86 g L−1 h−1 and the yield of 0.40 g g−1 sugar. SCP was also produced using NaOH-pretreated Miscanthus sinensis straw and corn steep liquor as the carbon and nitrogen sources through simultaneous saccharification and fermentation with the dry cell productivity of 0.23 g L−1 h−1 and yield of 0.17 g g−1 straw. C. intermedia FL023 was tolerant to 0.5 g L−1 furfural, acetic acid, and syringaldehyde in xylitol fermentation and produced 45.7 g L−1 xylitol from xylose with the productivity of 0.38 g L−1 h−1 and the yield of 0.57 g g−1 xylose. This study provides feasible methods for feed and food additive production from the abundant lignocellulosic bioresources.
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28
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Steinberg LM, Kronyak RE, House CH. Coupling of anaerobic waste treatment to produce protein- and lipid-rich bacterial biomass. Life Sci Space Res (Amst) 2017; 15:32-42. [PMID: 29198312 DOI: 10.1016/j.lssr.2017.07.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/26/2017] [Accepted: 07/18/2017] [Indexed: 06/07/2023]
Abstract
Future long-term manned space missions will require effective recycling of water and nutrients as part of a life support system. Biological waste treatment is less energy intensive than physicochemical treatment methods, yet anaerobic methanogenic waste treatment has been largely avoided due to slow treatment rates and safety issues concerning methane production. However, methane is generated during atmosphere regeneration on the ISS. Here we propose waste treatment via anaerobic digestion followed by methanotrophic growth of Methylococcus capsulatus to produce a protein- and lipid-rich biomass that can be directly consumed, or used to produce other high-protein food sources such as fish. To achieve more rapid methanogenic waste treatment, we built and tested a fixed-film, flow-through, anaerobic reactor to treat an ersatz wastewater. During steady-state operation, the reactor achieved a 97% chemical oxygen demand (COD) removal rate with an organic loading rate of 1740 g d-1 m-3 and a hydraulic retention time of 12.25 d. The reactor was also tested on three occasions by feeding ca. 500 g COD in less than 12 h, representing 50x the daily feeding rate, with COD removal rates ranging from 56-70%, demonstrating the ability of the reactor to respond to overfeeding events. While investigating the storage of treated reactor effluent at a pH of 12, we isolated a strain of Halomonas desiderata capable of acetate degradation under high pH conditions. We then tested the nutritional content of the alkaliphilic Halomonas desiderata strain, as well as the thermophile Thermus aquaticus, as supplemental protein and lipid sources that grow in conditions that should preclude pathogens. The M. capsulatus biomass consisted of 52% protein and 36% lipids, the H. desiderata biomass consisted of 15% protein and 7% lipids, and the Thermus aquaticus biomass consisted of 61% protein and 16% lipids. This work demonstrates the feasibility of rapid waste treatment in a compact reactor design, and proposes recycling of nutrients back into foodstuffs via heterotrophic (including methanotrophic, acetotrophic, and thermophilic) microbial growth.
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Affiliation(s)
- Lisa M Steinberg
- Department of Geosciences and Penn State Astrobiology Research Center, 220 Deike Building, Penn State University, University Park, PA 16802, United States
| | - Rachel E Kronyak
- Department of Geosciences and Penn State Astrobiology Research Center, 220 Deike Building, Penn State University, University Park, PA 16802, United States
| | - Christopher H House
- Department of Geosciences and Penn State Astrobiology Research Center, 220 Deike Building, Penn State University, University Park, PA 16802, United States.
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29
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Canedo MS, de Paula FG, da Silva FA, Vendruscolo F. Protein enrichment of brewery spent grain from Rhizopus oligosporus by solid-state fermentation. Bioprocess Biosyst Eng 2016; 39:1105-13. [PMID: 26984742 DOI: 10.1007/s00449-016-1587-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Accepted: 03/07/2016] [Indexed: 11/24/2022]
Abstract
Brewery spent grain represents approximately 85 % of total by-products generated in a brewery. Consisting of carbohydrates, fiber, minerals and low amounts of protein, the use of brewery spent grain is limited to the feeding of ruminants; however, its potential use should be investigated. The reuse of this by-product using microorganisms by solid-state fermentation process as the case of protein enrichment by single-cell protein incorporation is an alternative to ensure sustainability and generate commercially interesting products. In this context, the aim of this study was to grow Rhizopus oligosporus in brewery spent grain under different initial moisture contents and nitrogen sources to increase the protein content of the fermented material. After 7 days of fermentation, increase of 2-4 times in the crude protein and soluble protein content was verified, respectively, compared to unfermented brewery spent grain. The kinetics of protein enrichment demonstrated the possibility of application of this technique, which can be a great alternative for use in diets for animals.
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Affiliation(s)
- Marianny Silva Canedo
- Escola de Agronomia, Universidade Federal de Goiás, Caixa Postal 131, Goiânia, GO, CEP 74.690-900, Brazil
| | - Fernanda Gomes de Paula
- Escola de Veterinária e Zootecnia, Universidade Federal de Goiás, Caixa Postal 131, Goiânia, GO, CEP 74.690-900, Brazil
| | - Flávio Alves da Silva
- Escola de Agronomia, Universidade Federal de Goiás, Caixa Postal 131, Goiânia, GO, CEP 74.690-900, Brazil
| | - Francielo Vendruscolo
- Escola de Agronomia, Universidade Federal de Goiás, Caixa Postal 131, Goiânia, GO, CEP 74.690-900, Brazil.
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