1
|
Abdella A, Segato F, Wilkins MR. Optimization of process parameters and fermentation strategy for xylanase production in a stirred tank reactor using a mutant Aspergillus nidulans strain. ACTA ACUST UNITED AC 2020; 26:e00457. [PMID: 32420050 PMCID: PMC7218019 DOI: 10.1016/j.btre.2020.e00457] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/27/2020] [Accepted: 04/18/2020] [Indexed: 12/02/2022]
Abstract
In batch fermentation, xylanase productivity was 313 U/mL/day. Maximum xylanase productivity was achieved at aeration of 2 vvm and 400 rpm. The optimum kLa for an efficient xylanase production was found to be 38.5 h−1. Repeated batch fermentation increased xylanase productivity to 373 U/mL/day.
The present work studied the optimization of aeration rate, agitation rate and oxygen transfer and the use of various batch fermentation strategies for xylanase production from a recombinant Aspergillus nidulans strain in a 3 L stirred tank reactor. Maximum xylanase production of 1250 U/mL with productivity of 313 U/mL/day was obtained under an aeration rate of 2 vvm and an agitation rate of 400 rpm using batch fermentation. The optimum volumetric oxygen transfer coefficient (kLa) for efficient xylanase production was found to be 38.6 h−1. Fed batch mode and repeated batch fermentation was also performed with kLa was 38.6 h−1. Xylanase enzyme productivity increased to 327 with fed batch fermentation and 373 U/mL/day with repeated batch fermentation. Also, maximum xylanase activity increased to 1410 U/mL with fed batch fermentation and 1572 U/mL with repeated batch fermentation.
Collapse
Affiliation(s)
- Asmaa Abdella
- Department of Industrial Biotechnology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, PO Box 79, Sadat City, 22857 Egypt
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, 3605 Fair Street, Lincoln, NE, 68583-0726 USA
- Industrial Agricultural Products Center, University of Nebraska-Lincoln, 3605 Fair Street, Lincoln, NE, 68583-0730 USA
| | - Fernando Segato
- Synthetic and Molecular Biology Laboratory, Department of Biotechnology, Lorena School of Engineering, University of São Paulo, Estrada Municipal do Campinho, s/n, Lorena, SP, Brazil
| | - Mark R. Wilkins
- Department of Biological Systems Engineering, University of Nebraska-Lincoln, 3605 Fair Street, Lincoln, NE, 68583-0726 USA
- Industrial Agricultural Products Center, University of Nebraska-Lincoln, 3605 Fair Street, Lincoln, NE, 68583-0730 USA
- Department of Food Science and Technology, 1901 N 21stSt. University of Nebraska-Lincoln, Lincoln, NE, 68588-6205 USA
- Corresponding author at: University of Nebraska-Lincoln, 211 Chase Hall, PO Box 830726, Lincoln, NE, 68583-0726 USA.
| |
Collapse
|
2
|
Abdella A, Segato F, Wilkins MR. Optimization of nutrient medium components for production of a client endo-β-1,4-xylanase from Aspergillus fumigatus var. niveus using a recombinant Aspergillus nidulans strain. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.101267] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
3
|
Pardo-Planas O, Atiyeh HK, Prade RA, Müller M, Wilkins MR. Continuous aryl alcohol oxidase production under growth-limited conditions using a trickle bed reactor. BIORESOURCE TECHNOLOGY 2018; 255:149-155. [PMID: 29414160 DOI: 10.1016/j.biortech.2018.01.098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 01/19/2018] [Accepted: 01/20/2018] [Indexed: 06/08/2023]
Abstract
An A. nidulans strain with a pyridoxine marker was used for continuous production of aryl alcohol oxidase (AAO) in a trickle bed reactor (TBR). Modified medium with reduced zinc, no copper, and 5 g/L ascorbic acid that reduced melanin production and increased AAO productivity under growth limited conditions was used. Two air flow rates, 0.11 L/min (0.1 vvm) and 1.1 L/min (1.0 vvm) were tested. More melanin formation and reduced protein productivity were observed with air flow rate of 1.1 L/min. Three random packings were used as support for the fungus inside the TBR column, two of which were hydrophobic and one which was hydrophilic, and three different dilution rates were tested. The use of GEA BCN 030 hydrophobic packing resulted in greater AAO yield and productivity than the other packings. Increasing dilution rates favored melanin formation and citric, lactic and succinic acid accumulation, which decreased AAO yield and productivity.
Collapse
Affiliation(s)
- Oscar Pardo-Planas
- Department of Biosystems and Agricultural Engineering, 111 Agriculture Hall, Oklahoma State University, Stillwater, OK 74078, USA
| | - Hasan K Atiyeh
- Department of Biosystems and Agricultural Engineering, 111 Agriculture Hall, Oklahoma State University, Stillwater, OK 74078, USA
| | - Rolf A Prade
- Department of Microbiology and Molecular Genetics, 307 Life Sciences East, Oklahoma State University, Stillwater, OK 74078, USA
| | - Michael Müller
- Prüf-und-Forschungsinstitut Pirmasens, Marie-Curie-Straβe 19, 66953 Pirmasens, Germany
| | - Mark R Wilkins
- Department of Biosystems and Agricultural Engineering, 111 Agriculture Hall, Oklahoma State University, Stillwater, OK 74078, USA.
| |
Collapse
|
4
|
Pardo-Planas O, Prade RA, Müller M, Atiyeh HK, Wilkins MR. Prevention of melanin formation during aryl alcohol oxidase production under growth-limited conditions using an Aspergillus nidulans cell factory. BIORESOURCE TECHNOLOGY 2017; 243:874-882. [PMID: 28738504 DOI: 10.1016/j.biortech.2017.06.183] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 06/27/2017] [Accepted: 06/28/2017] [Indexed: 06/07/2023]
Abstract
An Aspergillus nidulans cell factory was genetically engineered to produce an aryl alcohol oxidase (AAO). The cell factory initiated production of melanin when growth-limited conditions were established using stationary plates and shaken flasks. This phenomenon was more pronounced when the strain was cultured in a trickle bed reactor (TBR). This study investigated different approaches to reduce melanin formation in fungal mycelia and liquid medium in order to increase the enzyme production yield. Removal of copper from the medium recipe reduced melanin formation in agar cultures and increased enzyme activities by 48% in agitated liquid cultures. Copper has been reported as a key element for tyrosinase, an enzyme responsible for melanin production. Ascorbic acid (0.44g/L) stopped melanin accumulation, did not affect growth parameters and resulted in AAO activity that was more than two-fold greater than a control treatment with no ascorbic acid.
Collapse
Affiliation(s)
- Oscar Pardo-Planas
- Department of Biosystems and Agricultural Engineering, 111 Agriculture Hall, Oklahoma State University, Stillwater, OK 74078, USA
| | - Rolf A Prade
- Department of Microbiology and Molecular Genetics, 307 Life Sciences East, Oklahoma State University, Stillwater, OK 74078, USA
| | - Michael Müller
- Prüf- und Forschungsinstitut Pirmasens e.V, Marie-Curie-Strasse 19, 66953 Pirmasens, Germany
| | - Hasan K Atiyeh
- Department of Biosystems and Agricultural Engineering, 111 Agriculture Hall, Oklahoma State University, Stillwater, OK 74078, USA
| | - Mark R Wilkins
- Department of Biosystems and Agricultural Engineering, 111 Agriculture Hall, Oklahoma State University, Stillwater, OK 74078, USA.
| |
Collapse
|
5
|
High-yield production of aryl alcohol oxidase under limited growth conditions in small-scale systems using a mutant Aspergillus nidulans strain. ACTA ACUST UNITED AC 2017; 44:247-257. [DOI: 10.1007/s10295-016-1884-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 12/03/2016] [Indexed: 10/20/2022]
Abstract
Abstract
Aryl alcohol oxidase (MtGloA) is an enzyme that belongs to the ligninolytic consortium and can play an important role in the bioenergy industry. This study investigated production of an MtGloA client enzyme by a mutant strain of Aspergillus nidulans unable to synthesize its own pyridoxine. Pyridoxine limitation can be used to control cell growth, diverting substrate to protein production. In agitated culture, enzyme production was similar when using media with 1 mg/L and without pyridoxine (26.64 ± 6.14 U/mg mycelia and 26.14 ± 8.39 U/mg mycelia using media with and without pyridoxine, respectively). However, the treatment lacking pyridoxine had to be supplemented with pyridoxine after 156 h of fermentation to sustain continued enzyme production. Use of extremely diluted pyridoxine levels allowed reduced fungal growth while maintaining steady enzyme production. Concentrations of 9 and 13.5 µg/L pyridoxine allowed MtGloA production with a growth rate of only 5% of that observed when using the standard 1 mg/L pyridoxine media.
Collapse
|
6
|
Classification, mode of action and production strategy of xylanase and its application for biofuel production from water hyacinth. Int J Biol Macromol 2016; 82:1041-54. [DOI: 10.1016/j.ijbiomac.2015.10.086] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 10/26/2015] [Accepted: 10/27/2015] [Indexed: 01/07/2023]
|
7
|
Müller M, Prade RA, Segato F, Atiyeh HK, Wilkins MR. Continuous xylanase production with Aspergillus nidulans under pyridoxine limitation using a trickle bed reactor. BIORESOURCE TECHNOLOGY 2015; 188:219-225. [PMID: 25683507 DOI: 10.1016/j.biortech.2015.01.085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 01/19/2015] [Accepted: 01/20/2015] [Indexed: 06/04/2023]
Abstract
A trickle bed reactor (TBR) with recycle was designed and tested using Aspergillus nidulans with a pyridoxine marker and over-expressing/secreting recombinant client xylanase B (XynB). The pyridoxine marker prevented the fungus from synthesizing its own pyridoxine and fungus was unable to grow when no pyridoxine was present in the medium; however, enzyme production was unaffected. Uncontrolled mycelia growth that led to clogging of the TBR was observed when fungus without a pyridoxine marker was used for XynB production. Using the fungus with pyridoxine marker, the TBR was operated continuously for 18 days and achieved a XynB output of 41 U/ml with an influent and effluent flow rate of 0.5 ml/min and a recycle flow rate of 56 ml/min. Production yields in the TBR were 1.4 times greater than a static tray culture and between 1.1 and 67 times greater than yields for SSF enzyme production stated in the literature.
Collapse
Affiliation(s)
- Michael Müller
- Department of Biosystems Engineering, Oklahoma State University, 111 Agriculture Hall, Stillwater, OK 74078, USA.
| | - Rolf A Prade
- Department of Microbiology and Molecular Genetics, Oklahoma State University, 307 Life Sciences East, Stillwater, OK 74078, USA.
| | - Fernando Segato
- Department of Microbiology and Molecular Genetics, Oklahoma State University, 307 Life Sciences East, Stillwater, OK 74078, USA
| | - Hasan K Atiyeh
- Department of Biosystems Engineering, Oklahoma State University, 111 Agriculture Hall, Stillwater, OK 74078, USA.
| | - Mark R Wilkins
- Department of Biosystems Engineering, Oklahoma State University, 111 Agriculture Hall, Stillwater, OK 74078, USA.
| |
Collapse
|