1
|
Sarikaya B, Bück H, Pohen G, Rodrigues F, Günster K, Wefelmeier K, Miebach K, Blank LM, Büchs J. Adaptive laboratory evolution in a novel parallel shaken pH-auxostat. Biotechnol Bioeng 2024. [PMID: 38932440 DOI: 10.1002/bit.28789] [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: 04/15/2024] [Accepted: 06/15/2024] [Indexed: 06/28/2024]
Abstract
Adaptive laboratory evolution (ALE) is a widely used microbial strain development and optimization method. ALE experiments, to select for faster-growing strains, are commonly performed as serial batch cultivations in shake flasks, serum bottles, or microtiter plates or as continuous cultivations in bioreactors on a laboratory scale. To combine the advantages of higher throughput in parallel shaken cultures with continuous fermentations for conducting ALE experiments, a new Continuous parallel shaken pH-auxostat (CPA) was developed. The CPA consists of six autonomous parallel shaken cylindrical reactors, equipped with real-time pH control of the culture medium. The noninvasive pH measurement and control are realized by biocompatible pH sensor spots and a programmable pump module, to adjust the dilution rate of fresh medium for each reactor separately. Two different strains of the methylotrophic yeast Ogataea polymorpha were used as microbial model systems for parallel chemostat and pH-auxostat cultivations. During cultivation, the medium is acidified by the microbial activity of the yeast. For pH-auxostat cultivations, the growth-dependent acidification triggers the addition of fresh feed medium into the reactors, leading to a pH increase and thereby to the control of the pH to a predetermined set value. By controlling the pH to a predetermined set value, the dilution rate of the continuous cultivation is adjusted to values close to the washout point, in the range of the maximum specific growth rate of the yeast. The pH control was optimized by conducting a step-response experiment and obtaining tuned PI controller parameters by the Chien-Hrones-Reswick (CHR) PID tuning method. Two pH-auxostat cultivations were performed with two different O. polymorpha strains at high dilution rates for up to 18 days. As a result, up to 4.8-fold faster-growing strains were selected. The increased specific maximum growth rates of the selected strains were confirmed in subsequent batch cultivations.
Collapse
Affiliation(s)
- Burak Sarikaya
- AVT-Biochemical Engineering, RWTH Aachen University, Aachen, Germany
| | - Hendrik Bück
- AVT-Biochemical Engineering, RWTH Aachen University, Aachen, Germany
| | - Gino Pohen
- AVT-Biochemical Engineering, RWTH Aachen University, Aachen, Germany
| | - Filipe Rodrigues
- AVT-Biochemical Engineering, RWTH Aachen University, Aachen, Germany
| | - Karsten Günster
- AVT-Biochemical Engineering, RWTH Aachen University, Aachen, Germany
| | - Katrin Wefelmeier
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Katharina Miebach
- AVT-Biochemical Engineering, RWTH Aachen University, Aachen, Germany
| | - Lars M Blank
- iAMB-Institute of Applied Microbiology, ABBt-Aachen Biology and Biotechnology, RWTH Aachen University, Aachen, Germany
| | - Jochen Büchs
- AVT-Biochemical Engineering, RWTH Aachen University, Aachen, Germany
| |
Collapse
|
2
|
Chu PH, Jenol MA, Phang LY, Ibrahim MF, Purkan P, Hadi S, Abd-Aziz S. Innovative approaches for amino acid production via consolidated bioprocessing of agricultural biomass. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:33303-33324. [PMID: 38710845 DOI: 10.1007/s11356-024-33534-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Accepted: 04/27/2024] [Indexed: 05/08/2024]
Abstract
Agricultural plantations in Indonesia and Malaysia yield substantial waste, necessitating proper disposal to address environmental concerns. Yet, these wastes, rich in starch and lignocellulosic content, offer an opportunity for value-added product development, particularly amino acid production. Traditional methods often rely on costly commercial enzymes to convert biomass into fermentable sugars for amino acid production. An alternative, consolidated bioprocessing, enables the direct conversion of agricultural biomass into amino acids using selected microorganisms. This review provides a comprehensive assessment of the potential of agricultural biomass in Indonesia and Malaysia for amino acid production through consolidated bioprocessing. It explores suitable microorganisms and presents a case study on using Bacillus subtilis ATCC 6051 to produce 9.56 mg/mL of amino acids directly from pineapple plant stems. These findings contribute to the advancement of sustainable amino acid production methods using agricultural biomass especially in Indonesia and Malaysia through consolidated bioprocessing, reducing waste and enhancing environmental sustainability.
Collapse
Affiliation(s)
- Pei-Hsia Chu
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
| | - Mohd Azwan Jenol
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
| | - Lai-Yee Phang
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
| | - Mohamad Faizal Ibrahim
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
| | - Purkan Purkan
- Biochemistry Division, Department of Chemistry, Faculty of Science and Technology, Airlangga University, Jl. Mulyorejo, Surabaya, 60115, Indonesia
| | - Sofijan Hadi
- Biochemistry Division, Department of Chemistry, Faculty of Science and Technology, Airlangga University, Jl. Mulyorejo, Surabaya, 60115, Indonesia
| | - Suraini Abd-Aziz
- Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia.
- Biochemistry Division, Department of Chemistry, Faculty of Science and Technology, Airlangga University, Jl. Mulyorejo, Surabaya, 60115, Indonesia.
| |
Collapse
|
3
|
Dinter C, Gumprecht A, Menze MA, Azizan A, Niehoff PJ, Hansen S, Büchs J. Validation of computational fluid dynamics of shake flask experiments at moderate viscosity by liquid distributions and volumetric power inputs. Sci Rep 2024; 14:3658. [PMID: 38351095 PMCID: PMC10864319 DOI: 10.1038/s41598-024-53980-7] [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: 09/06/2023] [Accepted: 02/07/2024] [Indexed: 02/16/2024] Open
Abstract
Computational fluid dynamics (CFD) has recently become a pivotal tool in the design and scale-up of bioprocesses. While CFD has been extensively utilized for stirred tank reactors (STRs), there exists a relatively limited body of literature focusing on CFD applications for shake flasks, almost exclusively concentrated on fluids at waterlike viscosity. The importance of CFD model validation cannot be overstated. While techniques to elucidate the internal flow field are necessary for model validation in STRs, the liquid distribution, caused by the orbital shaking motion of shake flasks, can be exploited for model validation. An OpenFOAM CFD model for shake flasks has been established. Calculated liquid distributions were compared to suitable, previously published experimental data. Across a broad range of shaking conditions, at waterlike and moderate viscosity (16.7 mPa∙s), the CFD model's liquid distributions align excellently with the experimental data, in terms of overall shape and position of the liquid relative to the direction of the centrifugal force. Additionally, the CFD model was used to calculate the volumetric power input, based on the energy dissipation. Depending on the shaking conditions, the computed volumetric power inputs range from 0.1 to 7 kW/m3 and differed on average by 0.01 kW/m3 from measured literature data.
Collapse
Affiliation(s)
- Carl Dinter
- RWTH Aachen University, Forckenbeckstraße 51, 52074, Aachen, Germany
| | - Andreas Gumprecht
- Evonik Operations GmbH, Rodenbacher Chaussee 4, 63457, Hanau-Wolfgang, Germany
| | | | - Amizon Azizan
- School of Chemical Engineering, College of Engineering, Universiti Teknologi MARA, 40450, Shah Alam, Selangor, Malaysia
| | | | - Sven Hansen
- Evonik Operations GmbH, Paul-Baumann-Straße 1, 45772, Marl, Germany
| | - Jochen Büchs
- RWTH Aachen University, Forckenbeckstraße 51, 52074, Aachen, Germany.
| |
Collapse
|