1
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Yan Q, Han L, Liu Z, Zhou S, Zhou Z. Stepwise genetic modification for efficient expression of heterologous proteins in Aspergillus nidulans. Appl Microbiol Biotechnol 2023; 107:6923-6935. [PMID: 37698610 DOI: 10.1007/s00253-023-12755-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 08/09/2023] [Accepted: 08/26/2023] [Indexed: 09/13/2023]
Abstract
Filamentous fungi are widely used in food fermentation and therapeutic protein production due to their prominent protein secretion and post-translational modification system. Aspergillus nidulans is an important model strain of filamentous fungi, but not a fully developed cell factory for heterologous protein expression. One of the limitations is its relatively low capacity of protein secretion. To alleviate this limitation, in this study, the protein secretory pathway and mycelium morphology were stepwise modified. With eGFP as a reporter protein, protein secretion was significantly enhanced through reducing the degradation of heterologous proteins by endoplasmic reticulum-associated protein degradation (ERAD) and vacuoles in the secretory pathway. Elimination of mycelial aggregation resulted in a 1.5-fold and 1.3-fold increase in secretory expression of eGFP in typical constitutive and inducible expression systems, respectively. Combined with these modifications, high secretory expression of human interleukin-6 (HuIL-6) was achieved. Consequently, a higher yield of secretory HuIL-6 was realized by further disruption of extracellular proteases. Overall, a superior chassis cell of A. nidulans suitable for efficient secretory expression of heterologous proteins was successfully obtained, providing a promising platform for biosynthesis using filamentous fungi as hosts. KEY POINTS: • Elimination of mycelial aggregation and decreasing the degradation of heterologous protein are effective strategies for improving the heterologous protein expression. • The work provides a high-performance chassis host △agsB-derA for heterologous protein secretory expression. • Human interleukin-6 (HuIL-6) was expressed efficiently in the high-performance chassis host △agsB-derA.
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Affiliation(s)
- Qin Yan
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Laichuang Han
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Zhongmei Liu
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, 214122, China
| | - Shengmin Zhou
- State Key Laboratory of Bioreactor Engineering, School of Biotechnology, East China University of Science and Technology, Shanghai, China.
| | - Zhemin Zhou
- School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China.
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, Jiangsu, 214122, China.
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2
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Kheirkhah T, Neubauer P, Junne S. Controlling Aspergillus niger morphology in a low shear-force environment in a rocking-motion bioreactor. Biochem Eng J 2023. [DOI: 10.1016/j.bej.2023.108905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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3
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Assessing Edible Filamentous Fungal Carriers as Cell Supports for Growth of Yeast and Cultivated Meat. Foods 2022; 11:foods11193142. [PMID: 36230217 PMCID: PMC9564274 DOI: 10.3390/foods11193142] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 09/03/2022] [Accepted: 09/05/2022] [Indexed: 12/03/2022] Open
Abstract
The growth and activity of adherent cells can be enabled or enhanced through attachment to a solid surface. For food and beverage production processes, these solid supports should be food-grade, low-cost, and biocompatible with the cell of interest. Solid supports that are edible can be a part of the final product, thus simplifying downstream operations in the production of fermented beverages and lab grown meat. We provide proof of concept that edible filamentous fungal pellets can function as a solid support by assessing the attachment and growth of two model cell types: yeast, and myoblast cells. The filamentous fungus Aspergillus oryzae was cultured to produce pellets with 0.9 mm diameter. These fugal pellets were inactivated by heat or chemical methods and characterized physicochemically. Chemically inactivated pellets had the lowest dry mass and were the most hydrophobic. Scanning electron microscope images showed that both yeast and myoblast cells naturally adhered to the fungal pellets. Over 48 h of incubation, immobilized yeast increased five-fold on active pellets and six-fold on heat-inactivated pellets. Myoblast cells proliferated best on heat-treated pellets, where viable cell activity increased almost two-fold, whereas on chemically inactivated pellets myoblasts did not increase in the cell mass. These results support the use of filamentous fungi as a novel cell immobilization biomaterial for food technology applications.
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Mahmoodi M, Nassireslami E. Control algorithms and strategies of feeding for fed-batch fermentation of Escherichia coli: a review of 40 years of experience. Prep Biochem Biotechnol 2021; 52:823-834. [PMID: 34730470 DOI: 10.1080/10826068.2021.1998112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Fed-batch cultivation is a well-known type of submerged fermentation that is frequently used in manufacture of recombinant proteins and various kinds of enzymes, owing to its ability to produce products with high concentrations and high efficiency. In fed-batch culture, several issues must be considered; most of them are also presented in batch culture. However, feed flow rate calculation only corresponds to fed-batch fermentation and its value has a significant impact on productivity, efficiency, final concentration of product, formation of by-products, and viscosity of the culture. From this background, the present review article is an effort to gather the information on feeding strategies for fed-batch cultivation of Escherichia coli, which is a well-known microorganism in the production of recombinant proteins and industrial enzymes, especially for therapeutic applications. Moreover, this review is an aid to comprehend and compare the fundamental concept of different feeding strategies and their advantages and drawbacks.
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Affiliation(s)
- Mohammad Mahmoodi
- Department of Pharmacology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Ehsan Nassireslami
- Department of Pharmacology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran.,Toxicology Research Center, AJA University of Medical Sciences, Tehran, Iran
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Ichikawa H, Miyazawa K, Komeiji K, Susukida S, Zhang S, Muto K, Orita R, Takeuchi A, Kamachi Y, Hitosugi M, Yoshimi A, Shintani T, Kato Y, Abe K. Improved recombinant protein production in Aspergillus oryzae lacking both α-1,3-glucan and galactosaminogalactan in batch culture with a lab-scale bioreactor. J Biosci Bioeng 2021; 133:39-45. [PMID: 34627690 DOI: 10.1016/j.jbiosc.2021.09.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 09/08/2021] [Accepted: 09/11/2021] [Indexed: 12/22/2022]
Abstract
Filamentous fungi are used as production hosts for various commercially valuable enzymes and chemicals including organic acids and secondary metabolites. We previously revealed that α-1,3-glucan and galactosaminogalactan (GAG) contribute to hyphal aggregation in the industrial fungus Aspergillus oryzae, and that production of recombinant protein in shake-flask culture is higher in a mutant lacking both α-1,3-glucan and GAG (AGΔ-GAGΔ) than in the parental strain. Here, we compared the productivity of the wild type, AGΔ-GAGΔ, and mutants lacking α-1,3-glucan (AGΔ) or GAG (GAGΔ) in batch culture with intermittent addition of glucose in a 5-L lab-scale bioreactor. The hyphae of the wild type and all mutants were dispersed by agitation, although the wild type and AGΔ formed small amounts of aggregates. Although mycelial weight was similar among the strains, the concentration of a secreted recombinant protein (CutL1) was the highest in AGΔ-GAGΔ. Evaluation of fluid properties revealed that the apparent viscosities of mycelial cultures of the wild type and AGΔ-GAGΔ decreased as the agitation speed was increased. The apparent viscosity of the AGΔ-GAGΔ culture tended to be lower than that of the wild-type strain at each agitation speed, and was significantly lower at 600 rpm. Overall, the lack of α-1,3-glucan and GAG in the hyphae improved culture rheology, resulting in an increase in recombinant protein production in AGΔ-GAGΔ. This is the first report of flow behavior improvement by a cell-surface component defect in a filamentous fungus.
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Affiliation(s)
- Hikaru Ichikawa
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Ken Miyazawa
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Keisuke Komeiji
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Shunya Susukida
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Silai Zhang
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Kiyoaki Muto
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Ryutaro Orita
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Ayumu Takeuchi
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Yuka Kamachi
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Masahiro Hitosugi
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Akira Yoshimi
- Laboratory of Environmental Interface Technology of Filamentous Fungi, Graduate School of Agriculture, Kyoto University, Oiwake-cho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan; ABE-Project, New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Takahiro Shintani
- Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan
| | - Yoshikazu Kato
- Mixing Technology Laboratory, Satake Chemical Equipment Mfg., Ltd., 60 Niizo, Toda, Saitama 335-0021, Japan
| | - Keietsu Abe
- Laboratory of Applied Microbiology, Department of Microbial Biotechnology, Graduate School of Agricultural Sciences, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan; ABE-Project, New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan; Department of Microbial Resources, Graduate School of Agricultural Science, Tohoku University, 468-1 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8572, Japan.
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Kalra R, Conlan XA, Goel M. Fungi as a Potential Source of Pigments: Harnessing Filamentous Fungi. Front Chem 2020; 8:369. [PMID: 32457874 PMCID: PMC7227384 DOI: 10.3389/fchem.2020.00369] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 04/08/2020] [Indexed: 12/20/2022] Open
Abstract
The growing concern over the harmful effects of synthetic colorants on both the consumer and the environment has raised a strong interest in natural coloring alternatives. As a result the worldwide demand for colorants of natural origin is rapidly increasing in the food, cosmetic and textile sectors. Natural colorants have the capacity to be used for a variety of industrial applications, for instance, as dyes for textile and non-textile substrates such as leather, paper, within paints and coatings, in cosmetics, and in food additives. Currently, pigments and colorants produced through plants and microbes are the primary source exploited by modern industries. Among the other non-conventional sources, filamentous fungi particularly ascomycetous and basidiomycetous fungi (mushrooms), and lichens (symbiotic association of a fungus with a green alga or cyanobacterium) are known to produce an extraordinary range of colors including several chemical classes of pigments such as melanins, azaphilones, flavins, phenazines, and quinines. This review seeks to emphasize the opportunity afforded by pigments naturally found in fungi as a viable green alternative to current sources. This review presents a comprehensive discussion on the capacity of fungal resources such as endophytes, halophytes, and fungi obtained from a range or sources such as soil, sediments, mangroves, and marine environments. A key driver of the interest in fungi as a source of pigments stems from environmental factors and discussion here will extend on the advancement of greener extraction techniques used for the extraction of intracellular and extracellular pigments. The search for compounds of interest requires a multidisciplinary approach and techniques such as metabolomics, metabolic engineering and biotechnological approaches that have potential to deal with various challenges faced by pigment industry.
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Affiliation(s)
- Rishu Kalra
- Division of Sustainable Agriculture, TERI-Deakin Nanobiotechnology Centre, The Energy and Resources Institute, Gurugram, India
| | - Xavier A Conlan
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC, Australia
| | - Mayurika Goel
- Division of Sustainable Agriculture, TERI-Deakin Nanobiotechnology Centre, The Energy and Resources Institute, Gurugram, India
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Sun X, Su X. Harnessing the knowledge of protein secretion for enhanced protein production in filamentous fungi. World J Microbiol Biotechnol 2019; 35:54. [PMID: 30900052 DOI: 10.1007/s11274-019-2630-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 03/08/2019] [Indexed: 12/19/2022]
Abstract
Filamentous fungi are important microorganisms used in industrial production of proteins and enzymes. Among these organisms, Trichoderma reesei, Aspergilli, and more recently Myceliophthora thermophile are the most widely used and promising ones which have powerful protein secretion capability. In recent years, there have been tremendous achievements in understanding the molecular mechanisms of the secretory pathways in filamentous fungi. The acquired pieces of knowledge can be harnessed to enhance protein production in filamentous fungi with assistance of state-of-the-art genetic engineering techniques.
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Affiliation(s)
- Xianhua Sun
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 South Zhongguancun Street, Beijing, 100081, China
| | - Xiaoyun Su
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 South Zhongguancun Street, Beijing, 100081, China.
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8
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Lin L, Sun Z, Li J, Chen Y, Liu Q, Sun W, Tian C. Disruption of gul-1 decreased the culture viscosity and improved protein secretion in the filamentous fungus Neurospora crassa. Microb Cell Fact 2018; 17:96. [PMID: 29908565 PMCID: PMC6004096 DOI: 10.1186/s12934-018-0944-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 06/12/2018] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND The cellulolytic fungus Neurospora crassa is considered a potential host for enzyme and bioethanol production. However, large scale applications are hindered by its filamentous growth. Although previous investigations have shown that mycelial morphology in submerged culture can be controlled by altering physical factors, there is little knowledge available about the potential for morphology control by genetic modification. RESULTS In this study, we screened morphological mutants in the filamentous fungus N. crassa. Of the 90 morphological mutants screened, 14 mutants exhibited considerably higher viscosity compared with that of the wild type strain, and only two mutants showed low-viscosity morphologies in submerged culture. We observed that disruption of gul-1 (NCU01197), which encodes an mRNA binding protein involved in cell wall remodeling, caused pellet formation as the fermentation progressed, and resulted in the most significant decrease in viscosity of culture broth. Moreover, over-expression of gul-1 caused dramatically increased viscosity, suggesting that the gul-1 had an important function in mycelial morphology during submerged cultivation. Transcriptional profiling showed that expression of genes encoding eight GPI-anchored cell wall proteins was lowered in Δgul-1 while expression of genes associated with two non-anchored cell wall proteins was elevated. Meanwhile, the expression levels of two hydrophobin genes were also significantly altered. These results suggested that GUL-1 affected the transcription of cell wall-related genes, thereby influencing cell wall structure and mycelial morphology. Additionally, the deletion of gul-1 caused increased protein secretion, probably due to a defect in cell wall integrity, suggesting this as an alternative strategy of strain improvement for enzyme production. To confirm practical applications, deletion of gul-1 in the hyper-cellulase producing strain (∆ncw-1∆Ncap3m) significantly reduced the viscosity of culture broth. CONCLUSIONS Using the model filamentous fungus N. crassa, genes that affect mycelial morphology in submerged culture were explored through systematic screening of morphological mutants. Disrupting several candidate genes altered viscosities in submerged culture. This work provides an example for controlling fungal morphology in submerged fermentation by genetic engineering, and will be beneficial for industrial fungal strain improvement.
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Affiliation(s)
- Liangcai Lin
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
| | - Zhiyong Sun
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
| | - Jingen Li
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
| | - Yong Chen
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
| | - Qian Liu
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
| | - Wenliang Sun
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
| | - Chaoguang Tian
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
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Wang G, Wu B, Zhao J, Haringa C, Xia J, Chu J, Zhuang Y, Zhang S, Heijnen JJ, van Gulik W, Deshmukh AT, Noorman HJ. Power input effects on degeneration in prolonged penicillin chemostat cultures: A systems analysis at flux, residual glucose, metabolite, and transcript levels. Biotechnol Bioeng 2017; 115:114-125. [DOI: 10.1002/bit.26447] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 07/14/2017] [Accepted: 09/01/2017] [Indexed: 12/28/2022]
Affiliation(s)
- Guan Wang
- State Key Laboratory of Bioreactor Engineering; East China University of Science and Technology (ECUST); Shanghai People's Republic of China
| | - Baofeng Wu
- State Key Laboratory of Bioreactor Engineering; East China University of Science and Technology (ECUST); Shanghai People's Republic of China
| | - Junfei Zhao
- State Key Laboratory of Bioreactor Engineering; East China University of Science and Technology (ECUST); Shanghai People's Republic of China
| | - Cees Haringa
- Transport Phenomena, Chemical Engineering Department; Delft University of Technology; Delft The Netherlands
| | - Jianye Xia
- State Key Laboratory of Bioreactor Engineering; East China University of Science and Technology (ECUST); Shanghai People's Republic of China
| | - Ju Chu
- State Key Laboratory of Bioreactor Engineering; East China University of Science and Technology (ECUST); Shanghai People's Republic of China
| | - Yingping Zhuang
- State Key Laboratory of Bioreactor Engineering; East China University of Science and Technology (ECUST); Shanghai People's Republic of China
| | - Siliang Zhang
- State Key Laboratory of Bioreactor Engineering; East China University of Science and Technology (ECUST); Shanghai People's Republic of China
| | - Joseph J. Heijnen
- Cell Systems Engineering, Department of Biotechnology; Delft University of Technology; Delft The Netherlands
| | - Walter van Gulik
- Cell Systems Engineering, Department of Biotechnology; Delft University of Technology; Delft The Netherlands
| | | | - Henk J. Noorman
- DSM Biotechnology Center; Delft The Netherlands
- Bio Process Engineering, Department of Biotechnology; Delft University of Technology; Delft The Netherlands
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Dubey MK, Zehra A, Aamir M, Meena M, Ahirwal L, Singh S, Shukla S, Upadhyay RS, Bueno-Mari R, Bajpai VK. Improvement Strategies, Cost Effective Production, and Potential Applications of Fungal Glucose Oxidase (GOD): Current Updates. Front Microbiol 2017; 8:1032. [PMID: 28659876 PMCID: PMC5468390 DOI: 10.3389/fmicb.2017.01032] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 05/23/2017] [Indexed: 01/15/2023] Open
Abstract
Fungal glucose oxidase (GOD) is widely employed in the different sectors of food industries for use in baking products, dry egg powder, beverages, and gluconic acid production. GOD also has several other novel applications in chemical, pharmaceutical, textile, and other biotechnological industries. The electrochemical suitability of GOD catalyzed reactions has enabled its successful use in bioelectronic devices, particularly biofuel cells, and biosensors. Other crucial aspects of GOD such as improved feeding efficiency in response to GOD supplemental diet, roles in antimicrobial activities, and enhancing pathogen defense response, thereby providing induced resistance in plants have also been reported. Moreover, the medical science, another emerging branch where GOD was recently reported to induce several apoptosis characteristics as well as cellular senescence by downregulating Klotho gene expression. These widespread applications of GOD have led to increased demand for more extensive research to improve its production, characterization, and enhanced stability to enable long term usages. Currently, GOD is mainly produced and purified from Aspergillus niger and Penicillium species, but the yield is relatively low and the purification process is troublesome. It is practical to build an excellent GOD-producing strain. Therefore, the present review describes innovative methods of enhancing fungal GOD production by using genetic and non-genetic approaches in-depth along with purification techniques. The review also highlights current research progress in the cost effective production of GOD, including key advances, potential applications and limitations. Therefore, there is an extensive need to commercialize these processes by developing and optimizing novel strategies for cost effective GOD production.
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Affiliation(s)
- Manish K. Dubey
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu UniversityVaranasi, India
| | - Andleeb Zehra
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu UniversityVaranasi, India
| | - Mohd Aamir
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu UniversityVaranasi, India
| | - Mukesh Meena
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu UniversityVaranasi, India
| | - Laxmi Ahirwal
- Laboratory of Molecular Biology, Department of Botany, Dr. Hari Singh Gour UniversitySagar, India
| | - Siddhartha Singh
- Laboratory of Molecular Biology, Department of Botany, Dr. Hari Singh Gour UniversitySagar, India
| | - Shruti Shukla
- Department of Energy and Materials Engineering, Dongguk UniversitySeoul, South Korea
| | - Ram S. Upadhyay
- Laboratory of Mycopathology and Microbial Technology, Centre of Advanced Study in Botany, Institute of Science, Banaras Hindu UniversityVaranasi, India
| | - Ruben Bueno-Mari
- Research and Development (R+D) Department, Laboratorios LokímicaValencia, Spain
| | - Vivek K. Bajpai
- Department of Applied Microbiology and Biotechnology, Yeungnam UniversityGyeongsan, South Korea
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11
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Wang ZJ, Shi HL, Wang P. The Online Morphology Control and Dynamic Studies on Improving Vitamin B12 Production by Pseudomonas denitrificans with Online Capacitance and Specific Oxygen Consumption Rate. Appl Biochem Biotechnol 2016; 179:1115-27. [PMID: 27022751 DOI: 10.1007/s12010-016-2053-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/14/2016] [Indexed: 10/22/2022]
Abstract
The relationship between the morphological character of Pseudomonas denitrificans and vitamin B12 synthesis based on real-time capacitance measurement and online specific oxygen consumption rate (Q O2) control was established for enhancing vitamin B12 production. Results demonstrated that the threshold Q O2 value lower than 2.0 mmol/gDCW/l would greatly stimulate the state transfer from the cell number growth phase to the cell elongation phase and promote rapid vitamin B12 biosynthesis, while the vitamin B12 biosynthesis rate could also be inhibited when the rate of cell's length-to-width ratio (ratio-LW) was higher than 10:1. Furthermore, the optimal morphology controlling strategy was achieved based on online Q O2 control, which increases the appropriate active cell numbers at the former phase, and then control the elongation of ratio-LW no more than 10:1 at the vitamin B12 biosynthesis phase. The maximal vitamin B12 production reached 239.7 mg/l at 168 h, which was improved by 14.7 % compared with the control (208 mg/l). This online controlling strategy would be effectively applied for improving industrial vitamin B12 fermentation.
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Affiliation(s)
- Ze-Jian Wang
- State Key Laboratory of Bioreactor Engineering, Shanghai Institute of Biomanufacturing Technology & Collaborative Innovation Center, East China University of Science and Technology, P.O. Box 329, 130 Meilong Road, Shanghai, 200237, China. .,Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628BC, Delft, The Netherlands.
| | - Hui-Lin Shi
- State Key Laboratory of Bioreactor Engineering, Shanghai Institute of Biomanufacturing Technology & Collaborative Innovation Center, East China University of Science and Technology, P.O. Box 329, 130 Meilong Road, Shanghai, 200237, China
| | - Ping Wang
- State Key Laboratory of Bioreactor Engineering, Shanghai Institute of Biomanufacturing Technology & Collaborative Innovation Center, East China University of Science and Technology, P.O. Box 329, 130 Meilong Road, Shanghai, 200237, China
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12
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Das RK, Brar SK, Verma M. A fermentative approach towards optimizing directed biosynthesis of fumaric acid by Rhizopus oryzae 1526 utilizing apple industry waste biomass. Fungal Biol 2015; 119:1279-1290. [DOI: 10.1016/j.funbio.2015.10.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/18/2015] [Accepted: 10/02/2015] [Indexed: 01/16/2023]
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13
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Modelling of the oxygen level response to feed rate perturbations in an industrial scale fermentation process. Process Biochem 2015. [DOI: 10.1016/j.procbio.2015.01.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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14
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Lu H, Li C, Tang W, Wang Z, Xia J, Zhang S, Zhuang Y, Chu J, Noorman H. Dependence of fungal characteristics on seed morphology and shear stress in bioreactors. Bioprocess Biosyst Eng 2015; 38:917-28. [DOI: 10.1007/s00449-014-1337-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 12/07/2014] [Indexed: 11/30/2022]
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15
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Quintanilla D, Hagemann T, Hansen K, Gernaey KV. Fungal Morphology in Industrial Enzyme Production--Modelling and Monitoring. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2015; 149:29-54. [PMID: 25724310 DOI: 10.1007/10_2015_309] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Filamentous fungi are widely used in the biotechnology industry for the production of industrial enzymes. Thus, considerable work has been done with the purpose of characterizing these processes. The ultimate goal of these efforts is to be able to control and predict fermentation performance on the basis of "standardized" measurements in terms of morphology, rheology, viscosity, mass transfer and productivity. However, because the variables are connected or dependent on each other, this task is not trivial. The aim of this review article is to gather available information in order to explain the interconnectivity between the different variables in submerged fermentations. An additional factor which makes the characterization of a fermentation broth even more challenging is that the data obtained are also dependent on the way they have been collected-meaning which technologies or probes have been used, and on the way the data is interpreted-i.e. which models were applied. The main filamentous fungi used in industrial fermentation are introduced, ranging from Trichoderma reesei to Aspergillus species. Due to the fact that secondary metabolites, like antibiotics, are not to be considered bulk products, organisms like e.g. Penicillium chrysogenum are just briefly touched upon for the description of some characterization techniques. The potential for development of different morphological phenotypes is discussed as well, also in view of what this could mean to productivity and-equally important-the collection of the data. An overview of the state of the art techniques for morphology characterization is provided, discussing methods that finally can be employed as the computational power has grown sufficiently in the recent years. Image analysis (IA) clearly benefits most but it also means that methods like near infrared measurement (NIR), capacitance and on-line viscosity now provide potential alternatives as powerful tools for characterizing morphology. These measuring techniques, and to some extent their combination, allow obtaining the data necessary for supporting the creation of mathematical models describing the fermentation process. An important part of this article will indeed focus on describing the different models, and on discussing their importance to fermentations of filamentous fungi in general. The main conclusion is that it has not yet been attempted to develop an overarching model that spans across strains and scales, as most studies indeed conclude that their respective results might be strain specific and not necessarily valid across scales.
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Affiliation(s)
- Daniela Quintanilla
- Department of Chemical and Biochemical Engineering, Technical University of Denmark (DTU), Building 229, 2800, Lyngby, Denmark
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16
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Serrano-Carreón L, Galindo E, Rocha-Valadéz JA, Holguín-Salas A, Corkidi G. Hydrodynamics, Fungal Physiology, and Morphology. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2015; 149:55-90. [PMID: 25652005 DOI: 10.1007/10_2015_304] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Filamentous cultures, such as fungi and actinomycetes, contribute substantially to the pharmaceutical industry and to enzyme production, with an annual market of about 6 billion dollars. In mechanically stirred reactors, most frequently used in fermentation industry, microbial growth and metabolite productivity depend on complex interactions between hydrodynamics, oxygen transfer, and mycelial morphology. The dissipation of energy through mechanically stirring devices, either flasks or tanks, impacts both microbial growth through shearing forces on the cells and the transfer of mass and energy, improving the contact between phases (i.e., air bubbles and microorganisms) but also causing damage to the cells at high energy dissipation rates. Mechanical-induced signaling in the cells triggers the molecular responses to shear stress; however, the complete mechanism is not known. Volumetric power input and, more importantly, the energy dissipation/circulation function are the main parameters determining mycelial size, a phenomenon that can be explained by the interaction of mycelial aggregates and Kolmogorov eddies. The use of microparticles in fungal cultures is also a strategy to increase process productivity and reproducibility by controlling fungal morphology. In order to rigorously study the effects of hydrodynamics on the physiology of fungal microorganisms, it is necessary to rule out the possible associated effects of dissolved oxygen, something which has been reported scarcely. At the other hand, the processes of phase dispersion (including the suspended solid that is the filamentous biomass) are crucial in order to get an integral knowledge about biological and physicochemical interactions within the bioreactor. Digital image analysis is a powerful tool for getting relevant information in order to establish the mechanisms of mass transfer as well as to evaluate the viability of the mycelia. This review focuses on (a) the main characteristics of the two most common morphologies exhibited by filamentous microorganisms; (b) how hydrodynamic conditions affect morphology and physiology in filamentous cultures; and (c) techniques using digital image analysis to characterize the viability of filamentous microorganisms and mass transfer in multiphase dispersions. Representative case studies of fungi (Trichoderma harzianum and Pleurotus ostreatus) exhibiting different typical morphologies (disperse mycelia and pellets) are discussed.
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Affiliation(s)
- L Serrano-Carreón
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, 62210, Cuernavaca, Mor, México,
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17
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Hadibarata T, Teh ZC. Optimization of pyrene degradation by white-rot fungus Pleurotus pulmonarius F043 and characterization of its metabolites. Bioprocess Biosyst Eng 2014; 37:1679-84. [PMID: 24554082 DOI: 10.1007/s00449-014-1140-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 01/26/2014] [Indexed: 11/28/2022]
Abstract
Pleurotus pulmonarius F043, a fungus collected from tropical rain forest, was used to degrade pyrene, a four-rings polycyclic aromatic hydrocarbons (PAHs), in a mineral medium broth. A maximum degradation rate of pyrene (90 %) was occurred at pH 3 and the lowest degradation rate was found in the culture at pH 10 (2 %). More than 90 % pyrene degradation was achieved at pH ranged from 3 to 5, whereas the degradation rate significantly declined when the pH was >5. The degradation of pyrene increased from 2 to 96 % when the temperature rose from 4 to 25 °C. When the temperature was increased to 60 °C resulting the lowest degradation rate into 7 %. Among the agitation rates tested, 120 rpm was the best with 95 % degradation, followed by 100 rpm (90 %). The optimum agitation range for pyrene degradation by P. pulmonarius F043 was 100-120 rpm. Among all the concentrations tested, 0.5 % Tween 80 was the best with 98 % degradation, followed by 1 % Tween 80 (90 %). The optimum concentration of Tween 80 for pyrene degradation by P. pulmonarius F043 was 0.5-1 %. The degradation rate decreased, while the concentration of Tween 80 was increased. The metabolic product was found during degradation process through the identification of gentisic acid by TLC, UV-Spectrophotometer, and GC-MS.
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Affiliation(s)
- Tony Hadibarata
- Institute of Environmental and Water Resource Management, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia,
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18
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Das RK, Brar SK. Enhanced Fumaric Acid Production from Brewery Wastewater and Insight into the Morphology of Rhizopus oryzae 1526. Appl Biochem Biotechnol 2014; 172:2974-88. [DOI: 10.1007/s12010-014-0739-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 01/10/2014] [Indexed: 12/01/2022]
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19
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Qiao B, Lu H, Cao YX, Chen R, Yuan YJ. Phospholipid profiles ofPenicillium chrysogenumin different scales of fermentations. Eng Life Sci 2013. [DOI: 10.1002/elsc.201200139] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Bin Qiao
- Key Laboratory of Systems Bioengineering, Ministry of Education; School of Chemical Engineering and Technology, Tianjin University; Tianjin P. R. China
| | - Hua Lu
- Key Laboratory of Systems Bioengineering, Ministry of Education; School of Chemical Engineering and Technology, Tianjin University; Tianjin P. R. China
- Hebei Zhongrun Pharmaceutical Co., Ltd; China, Shijiazhuang Pharmaceutical Group Co., Ltd. (CSPC); Shijiazhuang P. R. China
| | - Ying-Xiu Cao
- Key Laboratory of Systems Bioengineering, Ministry of Education; School of Chemical Engineering and Technology, Tianjin University; Tianjin P. R. China
| | - Rao Chen
- Hebei Zhongrun Pharmaceutical Co., Ltd; China, Shijiazhuang Pharmaceutical Group Co., Ltd. (CSPC); Shijiazhuang P. R. China
| | - Ying-Jin Yuan
- Key Laboratory of Systems Bioengineering, Ministry of Education; School of Chemical Engineering and Technology, Tianjin University; Tianjin P. R. China
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20
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Biotechnological production of ethanol from renewable resources by Neurospora crassa: an alternative to conventional yeast fermentations? Appl Microbiol Biotechnol 2013; 97:1457-73. [DOI: 10.1007/s00253-012-4655-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Revised: 12/11/2012] [Accepted: 12/13/2012] [Indexed: 12/21/2022]
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21
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Enhancement of n-decane hydroxylation activity of Monilliera sp. NAP 00702 in a liquid–liquid interface bioreactor by mixing of anion-exchange resin microparticles. Process Biochem 2012. [DOI: 10.1016/j.procbio.2012.10.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Fontana RC, da Silveira MM. Production of polygalacturonases by Aspergillus oryzae in stirred tank and internal- and external-loop airlift reactors. BIORESOURCE TECHNOLOGY 2012; 123:157-163. [PMID: 22940313 DOI: 10.1016/j.biortech.2012.07.053] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2012] [Revised: 07/13/2012] [Accepted: 07/16/2012] [Indexed: 06/01/2023]
Abstract
The production of endo- and exo-polygalacturonase (PG) by Aspergillus oryzae was assessed in stirred tank reactors (STRs), internal-loop airlift reactors (ILARs) and external-loop airlift reactors (ELARs). For STR production, we compared culture media formulated with either pectin (WBE) or partially hydrolyzed pectin. The highest enzyme activities were obtained in medium that contained 50% pectin in hydrolyzed form (WBE5). PG production in the three reactor types was compared for WBE5 and low salt WBE medium, with additional salts added at 48, 60 and 72h (WBES). The ELARs performed better than the ILARs in WBES medium where the exo-PG was the same concentration as for STRs and the endo-PG was 20% lower. These results indicate that PG production is higher under experimental conditions that result in higher cell growth with minimum pH values less than 3.0.
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Affiliation(s)
- Roselei Claudete Fontana
- Instituto de Biotecnologia, Universidade de Caxias do Sul, Caixa Postal 1352, CEP 95001-970, Caxias do Sul, RS, Brazil.
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Dhandapani B, Mahadevan S, Dhilipkumar SS, Rajkumar S, Mandal AB. Impact of aeration and agitation on metabolic heat and protease secretion of Aspergillus tamarii in a real-time biological reaction calorimeter. Appl Microbiol Biotechnol 2012; 94:1533-42. [DOI: 10.1007/s00253-012-3974-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 02/13/2012] [Accepted: 02/14/2012] [Indexed: 11/25/2022]
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24
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Dhandapani B, Mahadevan S, Mandal AB. Energetics of growth of Aspergillus tamarii in a biological real-time reaction calorimeter. Appl Microbiol Biotechnol 2011; 93:1927-36. [PMID: 22113563 DOI: 10.1007/s00253-011-3722-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2011] [Revised: 10/27/2011] [Accepted: 11/08/2011] [Indexed: 11/30/2022]
Abstract
Fungal cultivation in a biological real-time reaction calorimeter (BioRTCal) is arduous due to the heterogeneous nature of the system and difficulty in optimizing the process variables. The aim of this investigation is to monitor the growth of fungi Aspergillus tamarii MTCC 5152 in a calorimeter. Experiments carried out with a spore concentration of 10(5) spores/mL indicate that the growth based on biomass and heat generation profiles was comparable to those obtained hitherto. Heat yield due to biomass growth, substrate uptake, and oxygen uptake rate was estimated from calorimetric experiments. The results would be useful in fermenter design and scale-up. Heat of combustion of fungal biomass was determined experimentally and compared to the four models reported so far. The substrate concentration had significant effects on pellet formation with variation in pellet porosity and apparent density. Metabolic heat generation is an online process variable portraying the instantaneous activity of monitoring fungal growth and BioRTCal is employed to measure the exothermic heat in a noninvasive way.
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Affiliation(s)
- Balaji Dhandapani
- Chemical Engineering Department, Central Leather Research Institute, Adyar, Chennai, India, 600 020
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25
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Indigestible dextrin is an excellent inducer for α-amylase, α-glucosidase and glucoamylase production in a submerged culture of Aspergillus oryzae. Biotechnol Lett 2011; 34:347-51. [DOI: 10.1007/s10529-011-0777-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Accepted: 10/06/2011] [Indexed: 10/16/2022]
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26
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Zhou Z, Du G, Hua Z, Zhou J, Chen J. Optimization of fumaric acid production by Rhizopus delemar based on the morphology formation. BIORESOURCE TECHNOLOGY 2011; 102:9345-9349. [PMID: 21880482 DOI: 10.1016/j.biortech.2011.07.120] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 07/25/2011] [Accepted: 07/28/2011] [Indexed: 05/28/2023]
Abstract
The effects of temperature, agitation rate and medium composition, including concentrations of glucose, soybean peptone, and inorganic ions, on pellet formation and pellet diameter of Rhizopus delemar (Rhizopus oryzae) NRRL1526 during pre-culture were studied. Inorganic ions and soybean peptone had negative and positive effects on pellet formation, respectively. The initial glucose and soybean peptone concentrations directly affected pellet diameter. Within a certain range, pellet diameter decreased with increased initial substrate concentrations; however, above this range there was an opposite trend. Thus, optimal concentrations of substrate during pre-culture were beneficial for producing small pellets of R. delemar. Furthermore, dry cell mass and yield of fumaric acid tended to increase with decreased pellet diameter. Based on the pellet morphology optimization, the final fumaric acid concentration was improved by 46.13% when fermented in a flask and 31.82% in stirred bioreactor tank fermentation.
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Affiliation(s)
- Zhengxiong Zhou
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
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27
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BARRY D, WILLIAMS G. Microscopic characterisation of filamentous microbes: towards fully automated morphological quantification through image analysis. J Microsc 2011; 244:1-20. [DOI: 10.1111/j.1365-2818.2011.03506.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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28
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Albaek MO, Gernaey KV, Hansen MS, Stocks SM. Modeling enzyme production with Aspergillus oryzae in pilot scale vessels with different agitation, aeration, and agitator types. Biotechnol Bioeng 2011; 108:1828-40. [DOI: 10.1002/bit.23121] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Revised: 02/16/2011] [Accepted: 02/22/2011] [Indexed: 11/06/2022]
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29
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Osma JF, Toca-Herrera JL, Rodríguez-Couto S. Environmental, scanning electron and optical microscope image analysis software for determining volume and occupied area of solid-state fermentation fungal cultures. Biotechnol J 2010; 6:45-55. [DOI: 10.1002/biot.201000256] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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30
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Bredenkamp A, Velankar H, van Zyl WH, Görgens JF. Effect of dimorphic regulation on heterologous glucose oxidase production by Mucor circinelloides. Yeast 2010; 27:849-60. [DOI: 10.1002/yea.1793] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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31
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Effect of volumetric power input by aeration and agitation on pellet morphology and product formation of Aspergillus niger. Biochem Eng J 2010. [DOI: 10.1016/j.bej.2009.12.016] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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32
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Hadibarata T, Tachibana S. Characterization of phenanthrene degradation by strain polyporus sp. S133. J Environ Sci (China) 2010; 22:142-149. [PMID: 20397398 DOI: 10.1016/s1001-0742(09)60085-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Polyporus sp. S133, a fungus collected from contaminated soil, was used to degrade phenanthrene, a polycyclic aromatic hydrocarbon, in a mineral salt broth liquid culture. A maximal degradation rate (92%) was obtained when Polyporus sp. S133 was cultured for 30 days with agitation at 120 r/min, as compared to 44% degradation in non-agitated cultures. Furthermore, the degradation was affected by the addition of surfactants. Tween 80 was the most suitable surfactant for the degradation of phenanthrene by Polyporus sp. S133. The degradation rate increased as the amount of Tween 80 added increased. The rate in agitated cultures was about 2 times that in non-agitated cultures. The mechanism of degradation was determined through the identification of metabolites; 9,10-phenanthrenequinone, 2,2'-diphenic acid, phthalic acid, and protocatechuic acid. Several enzymes (manganese peroxidase, lignin peroxidase, laccase, 1,2-dioxygenase and 2,3-dioxygenase) produced by Polyporus sp. S133 were detected during the incubation. The highest level of activity was shown by 1,2-dioxygenase (187.4 U/L) after 20 days of culture.
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Affiliation(s)
- Tony Hadibarata
- Department of Applied Bioscience, Faculty ofAgriculture, Ehime University, 3-5-7 Tarumi, Matsuyama, Ehime, 790-8566, Japan.
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33
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Approaches for refining heterologous protein production in filamentous fungi. World J Microbiol Biotechnol 2009. [DOI: 10.1007/s11274-009-0128-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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34
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Abstract
It has been known for many years that oxygen (O2) may have toxic effects on aerobically growing microorganisms, mainly due to the threat arising from reactive oxygen species (ROS). In submerged culture industrial fermentation processes, maintenance of adequate levels of O2 (usually measured as dissolved oxygen tension (DOT)) can often be critical to the success of the manufacturing process. In viscous cultures of filamentous cultures, actively respiring, supplying adequate levels of O2 to the cultures by conventional air sparging is difficult and various strategies have been adopted to improve or enhance O2 transfer. However, adoption of those strategies to maintain adequate levels of DOT, that is, to avoid O2 limitation, may expose the fungi to potential oxidative damage caused by enhanced flux through the respiratory system. In the past, there have been numerous studies investigating the effects of DOT on fungal bioprocesses. Generally, in these studies moderately enhanced levels of O2 supply resulted in improvement in growth, product formation and acceptable morphological changes, while the negative impact of higher levels of DOT on morphology and product synthesis were generally assumed to be a consequence of "oxidative stress." However, very little research has actually been focused on investigation of this implicit link, and the mechanisms by which such effects might be mediated within industrial fungal processes. To elucidate this neglected topic, this review first surveys the basic knowledge of the chemistry of ROS, defensive systems in fungi and the effects of DOT on fungal growth, metabolism and morphology. The physiological responses of fungal cells to oxidative stress imposed by artificial and endogenous stressors are then critically reviewed. It is clear that fungi have a range of methods available to minimize the negative impacts of elevated ROS, but also that development of the various defensive systems or responses, can itself have profound consequences upon many process-related parameters. It is also clear that many of the practically convenient and widely used experimental methods of simulating oxidative stress, for example, addition of exogenous menadione or hydrogen peroxide, have effects on fungal cultures quite distinct from the effects of elevated levels of O2, and care must thus be exercised in the interpretation of results from such studies. The review critically evaluates our current understanding of the responses of fungal cultures to elevated O2 levels, and highlights key areas requiring further research to remedy gaps in knowledge.
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Affiliation(s)
- Zhonghu Bai
- Strathclyde Fermentation Center, Department of Bioscience, Strathclyde University, Glasgow, UK
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35
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Abstract
Fungal pellets of Aspergillus niger 405, Aspergillus ustus 326, and Stachybotrys sp. 1103 were used for the removal of humic substances from aqueous solutions. Batchwise biosorption, carried out at pH 6 and 25 degrees C, was monitored spectrophotometrically and the process described with Freundlich's model. Calculated sorption coefficients K(f) and n showed that A. niger exhibited the highest efficiency. A good match between the model and experimental data and a high correlation coefficient (R2) pointed out to judicious choice of the mechanism for removal of humic substances from the reaction medium. The sorption rate constants (k) for A. ustus and Stachybotrys sp. were almost equal, however higher than that for A. niger. Comparison of test results with the simulated ones demonstrated the applicability of the designed kinetic model for removal of humic substances from natural water by biosorption with fungal pellets. Different morphological structure of the examined fungal pellets showed that faster sorption does not imply the most efficient removal of humic substances. Desorption of humic substances from fungal pellets was complete, rapid, and yielded uniform results.
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Affiliation(s)
- Marija Vuković
- Division of Industrial Ecology, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, HR 10000 Zagreb, Croatia.
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36
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Rocha-Valadez JA, Albiter V, Caro MA, Serrano-Carreón L, Galindo E. A fermentation system designed to independently evaluate mixing and/or oxygen tension effects in microbial processes: development, application and performance. Bioprocess Biosyst Eng 2007; 30:115-22. [PMID: 17225992 DOI: 10.1007/s00449-006-0108-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Accepted: 12/15/2006] [Indexed: 10/23/2022]
Abstract
In order to evaluate the independent effects of hydrodynamic conditions and/or oxygen tension on culture physiology and productivity, a fermentation system designed to control dissolved oxygen at constant power drawn (P/V) was developed. The system included a fully instrumented 14 l bioreactor coupled to a PC for data acquisition and control. Power drawn was measured (using a commercial torquemeter coupled to the shaft) and maintained constant by varying the agitation speed; while gas blending was used to control dissolved oxygen concentration. To validate the system, rheological-complex fermentations involving xanthan gum production and filamentous fungal cultivation (using Xanthomonas campestris and Trichoderma harzianum) were developed. In both cases, and despite the changing environmental conditions (due to increased broth viscosities and microbial respiration), both variables were controlled at the desired set points. Through such a system, a rigorous evaluation of the hydrodynamic conditions and/or oxygen tension on culture physiology and productivity is now feasible.
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Affiliation(s)
- J A Rocha-Valadez
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, Mexico
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37
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Oncu S, Tari C, Unluturk S. Effect of Various Process Parameters on Morphology, Rheology, and Polygalacturonase Production byAspergillus sojaein a Batch Bioreactor. Biotechnol Prog 2007. [DOI: 10.1002/bp070079c] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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38
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Relationship between morphology, rheology and polygalacturonase production by Aspergillus sojae ATCC 20235 in submerged cultures. Biochem Eng J 2006. [DOI: 10.1016/j.bej.2006.09.023] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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39
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Kelly S, Grimm LH, Jonas R, Hempel DC, Krull R. Investigations of the Morphogenesis of Filamentous Microorganisms. Eng Life Sci 2006. [DOI: 10.1002/elsc.200620148] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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40
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Junker B. Measurement of bubble and pellet size distributions: past and current image analysis technology. Bioprocess Biosyst Eng 2006; 29:185-206. [PMID: 16855822 DOI: 10.1007/s00449-006-0070-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2006] [Accepted: 05/18/2006] [Indexed: 11/25/2022]
Abstract
Measurements of bubble and pellet size distributions are useful for biochemical process optimizations. The accuracy, representation, and simplicity of these measurements improve when the measurement is performed on-line and in situ rather than off-line using a sample. Historical and currently available measurement systems for photographic methods are summarized for bubble and pellet (morphology) measurement applications. Applications to cells, mycelia, and pellets measurements have driven key technological developments that have been applied for bubble measurements. Measurement trade-offs exist to maximize accuracy, extend range, and attain reasonable cycle times. Mathematical characterization of distributions using standard statistical techniques is straightforward, facilitating data presentation and analysis. For the specific application of bubble size distributions, selected bioreactor operating parameters and physicochemical conditions alter distributions. Empirical relationships have been established in some cases where sufficient data have been collected. In addition, parameters and conditions with substantial effects on bubble size distributions were identified and their relative effects quantified. This information was used to guide required accuracy and precision targets for bubble size distribution measurements from newly developed novel on-line and in situ bubble measurement devices.
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Affiliation(s)
- Beth Junker
- Fermentation and Development Operations, Merck Research Laboratories, RY810-127, PO Box 2000, Rahway, NJ 07065, USA.
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41
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Kelly S, Grimm L, Jonas R, Krull R, Hempel D. Untersuchungen zur Morphogenese myzelbildender Mikroorganismen. CHEM-ING-TECH 2006. [DOI: 10.1002/cite.200500159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Papagianni M, Mattey M. Morphological development of Aspergillus niger in submerged citric acid fermentation as a function of the spore inoculum level. Application of neural network and cluster analysis for characterization of mycelial morphology. Microb Cell Fact 2006; 5:3. [PMID: 16433930 PMCID: PMC1386700 DOI: 10.1186/1475-2859-5-3] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2005] [Accepted: 01/25/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Although the citric acid fermentation by Aspergillus niger is one of the most important industrial microbial processes and various aspects of the fermentation appear in a very large number of publications since the 1950s, the effect of the spore inoculum level on fungal morphology is a rather neglected area. The aim of the presented investigations was to quantify the effects of changing spore inoculum level on the resulting mycelial morphology and to investigate the physiology that underlines the phenomena. Batch fermentations were carried out in a stirred tank bioreactor, which were inoculated directly with spores in concentrations ranging from 10(4) to 10(9) spores per ml. Morphological features, evaluated by digital image analysis, were classified using an artificial neural network (ANN), which considered four main object types: globular and elongated pellets, clumps and free mycelial trees. The significance of the particular morphological features and their combination was determined by cluster analysis. RESULTS Cell volume fraction analysis for the various inoculum levels tested revealed that by rising the spore inoculum level from 10(4) to 10(9) spores per ml, a clear transition from pelleted to dispersed forms occurs. Glucosamine formation and release by the mycelium appears to be related to spore inoculum level. Maximum concentrations detected in fermentations inoculated with 10(4) and 10(5) spores/ml, where pellets predominated. At much higher inoculum levels (10(8), 10(9) spores/ml), lower dissolved oxygen levels during the early fermentation phase were associated with slower ammonium ions uptakes and significantly lower glucosamine concentrations while the mycelium developed in dispersed morphologies. A big increase in the main and total hyphal lengths and branching frequency was observed in mycelial trees as inoculum levels rise from 10(4) to 10(9) spores/ml, while in aggregated forms particle sizes and their compactness decreased. CONCLUSION The methods used in this study, allowed for the detailed quantification of the transition between the two extreme morphological forms. The impact of spore inoculum level on the detailed characteristics of the particular morphological forms produced was high. Control of mycelial morphology is often regarded as a prerequisite to ensure increased productivities in industrial applications. The research described here demonstrates that adjusting the spore inoculum level controls effectively mycelial morphology.
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Affiliation(s)
- Maria Papagianni
- Department of Hygiene and Technology of Food of Animal Origin, School of Veterinary Medicine, Aristotle University of Thessaloniki, Thessaloniki 54006, Greece
| | - Michael Mattey
- Department of Bioscience, University of Strathclyde, Royal College Building, 204 George street, Glasgow G1 1XW, UK
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Rodríguez Porcel E, Casas López J, Sánchez Pérez J, Fernández Sevilla J, Chisti Y. Effects of pellet morphology on broth rheology in fermentations of Aspergillus terreus. Biochem Eng J 2005. [DOI: 10.1016/j.bej.2005.04.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Rocha-Valadez JA, Hassan M, Corkidi G, Flores C, Galindo E, Serrano-Carreón L. 6-pentyl-alpha-pyrone production by Trichoderma harzianum: the influence of energy dissipation rate and its implications on fungal physiology. Biotechnol Bioeng 2005; 91:54-61. [PMID: 15880469 DOI: 10.1002/bit.20489] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The influence of the agitation conditions on biomass growth, morphology, carbon metabolism, viability, and 6-pentyl-alpha-pyrone (6PP) production by Trichoderma harzianum were studied in an extractive fermentation system. Batch spore-inoculated cultures developed at dissolved oxygen concentrations above 35% of air saturation were carried out in a 14 L bioreactor. The effect of energy dissipation rate over culture performance was assessed using two sets of three Rushton turbines (having different diameters) operated at different agitation speeds. Higher mechanical stress enhanced cellular differentiation (i.e., sporulation), while yielding lower specific growth rates and increased specific CO(2) production rates (CPRs) at relatively constant specific glucose consumption rates. In addition, fungal viability and clump mean diameter decreased gradually at higher energy dissipation rates. 6PP biosynthesis was growth associated and its specific productivity showed a bell-shaped relationship with the energy dissipation rate. T. harzianum physiology was, therefore, strongly influenced by the prevailing hydrodynamic conditions as it triggered cellular metabolism and differentiation shifts.
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Affiliation(s)
- J Antonio Rocha-Valadez
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, 62210 Morelos, México
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Károlyi G. Fractal scaling of microbial colonies affects growth. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2005; 71:031915. [PMID: 15903467 DOI: 10.1103/physreve.71.031915] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2004] [Indexed: 05/02/2023]
Abstract
The growth dynamics of filamentary microbial colonies is investigated. Fractality of the fungal or actinomycetes colonies is shown both theoretically and in numerical experiments to play an important role. The growth observed in real colonies is described by the assumption of time-dependent fractality related to the different ages of various parts of the colony. The theoretical results are compared to a simulation based on branching random walks.
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Affiliation(s)
- György Károlyi
- Center for Applied Mathematics and Computational Physics, and Department of Structural Mechanics, Budapest University of Technology and Economics, Hungary.
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Bhargava S, Wenger KS, Rane K, Rising V, Marten MR. Effect of cycle time on fungal morphology, broth rheology, and recombinant enzyme productivity during pulsed addition of limiting carbon source. Biotechnol Bioeng 2005; 89:524-9. [PMID: 15643626 DOI: 10.1002/bit.20355] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
For many years, high broth viscosity has remained a key challenge in large-scale filamentous fungal fermentations. In previous studies, we showed that broth viscosity could be reduced by pulsed addition of limiting carbon during fed-batch fermentation. The objective in this study was to determine how changing the frequency of pulsed substrate addition affects fungal morphology, broth rheology, and recombinant enzyme productivity. To accomplish this, a series of duplicate fed-batch fermentations were performed in 20-L fermentors with a recombinant glucoamylase producing strain of Aspergillus oryzae. The total cycle time for substrate pulsing was varied over a wide range (30-2,700 s), with substrate added only during the first 30% of each cycle. As a control, a fermentation was conducted with continuous substrate feeding, and in all fermentations the same total amount of substrate was added. Results show that the total biomass concentration remained relatively unaltered, while a substantial decrease in the mean projected area of fungal elements (i.e., average size) was observed with increasing cycle time. This led to reduced broth viscosity and increased oxygen uptake rate. However, high values of cycle time (i.e., 900-2,700 s) showed a significant increase in fungal conidia formation and significantly reduced recombinant enzyme productivity, suggesting that the fungi channeled substrate to storage compounds rather than to recombinant protein. In addition to explaining the effect of cycle time on fermentation performance, these results may aid in explaining the discrepancies observed on scale-up to larger fermentors.
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Affiliation(s)
- Swapnil Bhargava
- University of Maryland, Baltimore County, Department of Chemical and Biochemical Engineering, 1000 Hilltop Circle, Baltimore, Maryland 21250, USA
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Wang R, Chau Sing Law R, Webb C. Protease production and conidiation by Aspergillus oryzae in flour fermentation. Process Biochem 2005. [DOI: 10.1016/j.procbio.2003.12.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Casas López JL, Sánchez Pérez JA, Fernández Sevilla JM, Rodríguez Porcel EM, Chisti Y. Pellet morphology, culture rheology and lovastatin production in cultures of Aspergillus terreus. J Biotechnol 2004; 116:61-77. [PMID: 15652430 DOI: 10.1016/j.jbiotec.2004.10.005] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2004] [Revised: 10/07/2004] [Accepted: 10/13/2004] [Indexed: 12/16/2022]
Abstract
Pellet growth of Aspergillus terreus ATCC 20542 in submerged batch fermentations in stirred bioreactors was used to examine the effects of agitation (impeller tip speed u(t) of 1.01-2.71 ms(-1)) and aeration regimens (air or an oxygen-enriched mixture containing 80% oxygen and 20% nitrogen by volume) on the fungal pellet morphology, broth rheology and lovastatin production. The agitation speed and aeration methods used did not affect the biomass production profiles, but significantly influenced pellet morphology, broth rheology and the lovastatin titers. Pellets of approximately 1200 microm initial diameter were reduced to a final stable size of approximately 900 microm when the agitation intensity was >/=600 rpm (u(t)>/=2.03 ms(-1)). A stable pellet diameter of approximately 2500 microm could be attained in less intensely agitated cultures. These large fluffy pellets produced high lovastatin titers when aerated with oxygen-enriched gas but not with air. Much smaller pellets obtained under highly agitated conditions did not attain high lovastatin productivity even in an oxygen-enriched atmosphere. This suggests that both an upper limit on agitation intensity and a high level of dissolved oxygen are essential for attaining high titers of lovastatin. Pellet size in the bioreactor correlated equally well with the specific energy dissipation rate and the energy dissipation circulation function. The latter took into account the frequency of passage of the pellets through the high shear regions of the impellers. Pellets that gave high lovastatin titers produced highly shear thinning cultivation broths.
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Affiliation(s)
- J L Casas López
- Department of Chemical Engineering, University of Almería, 04120 Almería, Spain.
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Bennamoun L, Meraihi Z, Dakhmouche S. Utilisation de la planification expérimentale pour l'optimisation de la production de l'α-amylase par Aspergillus oryzae Ahlburg (Cohen) 1042.72 cultivé sur milieu à base de déchets d'oranges. J FOOD ENG 2004. [DOI: 10.1016/j.jfoodeng.2003.10.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kelly S, Grimm LH, Hengstler J, Schultheis E, Krull R, Hempel DC. Agitation effects on submerged growth and product formation of Aspergillus niger. Bioprocess Biosyst Eng 2004; 26:315-23. [PMID: 15309605 DOI: 10.1007/s00449-004-0368-y] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2003] [Accepted: 06/30/2004] [Indexed: 10/26/2022]
Abstract
Product formation of mycelial organisms, like Aspergillus niger, is intimately connected with their morphology. Pellet morphology is often requested for product formation. Therefore, it is important to reveal the influence of the hydrodynamic conditions on the morphological development. In the present study, pellet morphology and glucoamylase formation were studied under different agitation intensities of A. niger AB1.13. For pellet formation inside the bioreactor, without the use of precultures, it is necessary to work at low energy dissipation rates. Biomass growth and glucoamylase activity were correlated with energy dissipation. Furthermore, product yield was analysed in dependence of pellet size and concentration. The present work shows that simple equations based on Monod-kinetics can describe growth and product formation, in general, also in mycelian organisms. All measured morphological data, like pellet concentration, as well as glucoamylase formation, strongly depend on the hydrodynamic conditions.
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Affiliation(s)
- Sven Kelly
- Institute of Biochemical Engineering, Technical University of Braunschweig, 38106 Braunschweig, Germany.
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