Optimization and Analysis of Fermentation Process for Microbial Products

A special issue of Fermentation (ISSN 2311-5637). This special issue belongs to the section "Industrial Fermentation".

Deadline for manuscript submissions: closed (31 March 2024) | Viewed by 26125

Special Issue Editors

Department of Bioengineering, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250353, China
Interests: food biotechnology; microbial fermentation engineering; metabolic engineering
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Guest Editor
Department of Bioengineering, Qilu University of Technology, Jinan, China
Interests: food biotechnology; fermentation engineering

Special Issue Information

Dear Colleagues,

Fermentation process optimization refers to the improvement of the production, productivity and conversion rate of target metabolites in the fermenter through the control of operating conditions on the basis of the obtained high-yield strain. The fermentation process is usually carried out in a specific reactor. Since the microbial reaction is a self-catalytic reaction, the microbial cell itself is also a reactor, and all the substances to come out of the microreactor of the cell must pass through the boundary line between the cell and the environment, so that all reactions that occur in the cell (i.e., the biological phase) are closely linked to the environmental condition (i.e., the abiotic phase). The actual biological reaction system is a very complex three-phase system, that is, a mixture of gas, liquid and solid phases, and the concentration gradient between the three phases varies greatly, by several orders of magnitude. Therefore, to optimize such a complex system, an elaborate analysis and study of the fermentation process must be done.

The aim of this Special Issue is to publish both recent innovative research results as well as review papers on the optimization and analysis of fermentation processes for microbial products.

Sincerely,

Dr. Xidong Ren
Dr. Deqiang Zhu
Guest Editors

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Keywords

  • process optimization
  • fermentation
  • transcriptomics
  • proteomics
  • metabolomics
  • regulatory mechanism

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Published Papers (13 papers)

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Research

Jump to: Review

12 pages, 1891 KiB  
Article
Optimizing Curdlan Synthesis: Engineering Agrobacterium tumefaciens ATCC31749 for Enhanced Production Using Dextrin as a Carbon Source
by Tingting Yu, Yu Wang, Wei Wang, Yonggang Zhang, Yanmin Zhang, Hongyu Han, Yang Liu, Siduo Zhou and Xueqian Dong
Fermentation 2024, 10(5), 240; https://doi.org/10.3390/fermentation10050240 - 30 Apr 2024
Viewed by 1393
Abstract
A key goal in current research on industrial curdlan production is the expansion of carbon sources for fermentation. In this study, a recombinant bacterial strain, sp-AmyAXCC, capable of fermenting and synthesizing curdlan using dextrin as a carbon source, was produced via heterologous expression [...] Read more.
A key goal in current research on industrial curdlan production is the expansion of carbon sources for fermentation. In this study, a recombinant bacterial strain, sp-AmyAXCC, capable of fermenting and synthesizing curdlan using dextrin as a carbon source, was produced via heterologous expression of IPTG-inducible α-amylase from Xanthomonas campestris NRRL B-1459 in Agrobacterium tumefaciens ATCC31749. External expression of the enzyme was confirmed by western blotting, and the expression levels of exogenous proteins during the fermentation process were monitored. Additionally, the properties of the curdlan product were characterized using attenuated total reflectance-Fourier transform infrared spectroscopy and X-ray diffraction. The recombinant strain produced curdlan at a titer of 30.40 ± 0.14 g/L, gel strength of 703.5 ± 34.2 g/cm2, and a molecular weight of 3.58 × 106 Da, which is 33% greater than the molecular weight of native curdlan (2.69 × 106 Da). In the batch fermentation of sp-AmyAXCC with 12% dextrin as a carbon source, the titer of curdlan was 66.7 g/L with a yield of 0.56 g/g, and a productivity rate of 0.62 g/L/h at 108 h. The results of this study expand the substrate spectrum for Agrobacterium fermentation in curdlan production and provides guidance for further industrialization of curdlan production. Full article
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13 pages, 1595 KiB  
Article
Optimization of Fermentation Process of Wheat Germ Protein by Aspergillus niger and Analysis of Antioxidant Activity of Peptide
by Yingying Liu, Yu Zhou, Chaohong Zhu, Yanglin Meng, Jingjing Wang, Xinyang Chen, Yinchen Hou, Aimei Liao, Long Pan and Jihong Huang
Fermentation 2024, 10(3), 121; https://doi.org/10.3390/fermentation10030121 - 22 Feb 2024
Viewed by 2157
Abstract
Utilizing wheat embryos as the raw material and employing Aspergillus niger as the fermentation strain, wheat embryo polypeptides were produced through microbial liquid fermentation. The protein concentration post-fermentation served as the response variable, and the preparation process underwent optimization through single-factor testing and [...] Read more.
Utilizing wheat embryos as the raw material and employing Aspergillus niger as the fermentation strain, wheat embryo polypeptides were produced through microbial liquid fermentation. The protein concentration post-fermentation served as the response variable, and the preparation process underwent optimization through single-factor testing and a response surface methodology, followed by the assessment of antioxidant activity. The findings revealed that the optimal conditions for wheat embryo peptide preparation via Aspergillus niger fermentation included a fermentation duration of 24 h, an inoculum volume of 4%, an initial pH of 7, and a protein concentration of 21.47 mg/mL. Peptides with different molecular weights were then prepared by dead-end filtration. The results showed that F6 (<3 kDa) had strong scavenging ability against DPPH, ABTS, and ·OH radicals, which provided a basis for the preparation of antioxidant peptides in wheat germ and related research. Full article
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16 pages, 2490 KiB  
Article
Two-Step Optimization for Improving Prodigiosin Production Using a Fermentation Medium for Serratia marcescens and an Extraction Process
by Xin Wang, Zhihao Cui, Zongyu Zhang, Jiacheng Zhao, Xiaoquan Liu, Guangfan Meng, Jing Zhang and Jie Zhang
Fermentation 2024, 10(2), 85; https://doi.org/10.3390/fermentation10020085 - 30 Jan 2024
Viewed by 2530
Abstract
Prodigiosin (PG) is a secondary metabolite produced by Serratia marcescens which has a promising future in food, textile, and other industries due to its bright color and diverse biological activities. Currently, the production of PG is mainly restricted by the components of the [...] Read more.
Prodigiosin (PG) is a secondary metabolite produced by Serratia marcescens which has a promising future in food, textile, and other industries due to its bright color and diverse biological activities. Currently, the production of PG is mainly restricted by the components of the fermentation medium and large losses during its extraction process, making large-scale industrial production impossible. In this study, a Box–Behnken design (BBD) was used to optimize the response surface of the fermentation medium of S. marcescens. The optimum medium composition was found to be sucrose, 16.29 g/L; peptone, 11.76 g/L; and tween 80, 2.64 g/L. This composition produced a PG amount of 1653.95 ± 32.12 mg/L, which is a 64-fold increase compared to the initial medium. A Box–Behnken design (BBD) was then used to optimize the response surface of the extraction process of PG, aiming to reduce loss during extraction. The optimal extraction conditions were determined to be a solvent fermentation liquid ratio of 9.12:1, an extraction temperature of 25.35 °C, and an extraction time of 30.33 min. These conditions resulted in a final PG production amount of 2142.75 ± 12.55 mg/L, which was nearly 84 times higher than the initial production amount of PG. These results provide essential theoretical and experimental support for the industrial production of PG. Full article
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17 pages, 2975 KiB  
Article
Identification and Combinatorial Overexpression of Key Genes for Enhancing ε-Poly-L-lysine Biosynthesis in Streptomyces albulus
by Hongjian Zhang, Hao Yang, Chongyang Zhang, Daojun Zhu, Liang Wang, Jianhua Zhang and Xusheng Chen
Fermentation 2024, 10(1), 65; https://doi.org/10.3390/fermentation10010065 - 17 Jan 2024
Cited by 1 | Viewed by 1483
Abstract
ε-Poly-L-lysine (ε-PL) is a natural and safe food preservative mainly produced by the aerobic, filamentous bacterium Streptomyces albulus. Therefore, it is crucial to breed superior ε-PL-producing strains to enhance fermentation efficiency to reduce production costs. Metabolic engineering is an effective measure for [...] Read more.
ε-Poly-L-lysine (ε-PL) is a natural and safe food preservative mainly produced by the aerobic, filamentous bacterium Streptomyces albulus. Therefore, it is crucial to breed superior ε-PL-producing strains to enhance fermentation efficiency to reduce production costs. Metabolic engineering is an effective measure for strain modification, but there are few reports on key genes for ε-PL biosynthesis. In this study, metabolic flux analysis was employed to identify potential key genes in ε-PL biosynthesis in S. albulus WG-608. A total of six potential key genes were identified. Three effective key genes (ppc, pyc and pls) were identified for the first time in ε-PL biosynthesis through overexpression experiments. It also presents the first demonstration of the promoting effects of ppc and pyc on ε-PL biosynthesis. Three genes were then co-expressed in S. albulus WG-608 to obtain OE-ppc-pyc-pls, which exhibited an 11.4% increase in ε-PL production compared to S. albulus WG-608, with a 25.5% increase in specific ε-PL production. Finally, the metabolic flux analysis of OE-ppc-pyc-pls compared to S. albulus WG-608 demonstrated that OE-ppc-pyc-pls successfully altered the metabolic flux as expected. This study not only provides a theoretical basis for the metabolic engineering of ε-PL-producing strains but also provides an effective approach for the metabolic engineering of other metabolites. Full article
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14 pages, 2586 KiB  
Article
Transcriptional Analysis of Antrodin C Synthesis in Taiwanofungus camphoratus (Syn. Antrodia camphorate, Antrodia cinnamomea) to Understand Its Biosynthetic Mechanism
by Wei Jia, Shu-Ping Gai, Xiao-Hui Li, Jing-Song Zhang and Wen-Han Wang
Fermentation 2024, 10(1), 28; https://doi.org/10.3390/fermentation10010028 - 29 Dec 2023
Cited by 1 | Viewed by 1432
Abstract
Antrodin C, a bioactive component of Taiwanofungus camphoratus, exhibits good immunophysiological and antitumour activities, including a broad spectrum of anticancer effects. Exogenous additives can bind to metabolites during the submerged culture of T. camphoratus and affect secondary metabolite yields. However, the lack [...] Read more.
Antrodin C, a bioactive component of Taiwanofungus camphoratus, exhibits good immunophysiological and antitumour activities, including a broad spectrum of anticancer effects. Exogenous additives can bind to metabolites during the submerged culture of T. camphoratus and affect secondary metabolite yields. However, the lack of molecular genetic studies on T. camphoratus has hindered the study of the antrodin C biosynthetic pathway. In this study, we conducted a ribonucleic acid-sequencing-based transcriptional analysis to identify the differentially expressed genes involved in the synthesis of antrodin C by T. camphoratus, using inositol and maleic acid (MAC) as exogenous additives. The addition of inositol significantly upregulated carbohydrate and sugar metabolism pathway genes (E3.2.1.14, UGDH, and IVD). When MAC was used, amino and nucleotide sugar metabolism and starch and sucrose metabolism pathways were significantly inhibited, and the associated genes (E3.2.1.14 and E3.2.1.58) were also significantly downregulated. The biosynthesis pathway genes for ubiquinone and other terpene quinones (COQ2, ARO8, and wrbA), which may play an important role in antrodin C synthesis, were significantly downregulated. This study advances our understanding of how the additives inositol and MAC affect metabolite biosynthesis in T. camphorates. This could be beneficial in proposing potential strategies for improving antrodin C production using a genetic approach. Full article
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16 pages, 5709 KiB  
Article
Comprehensive Analysis of Catalytic Characteristics and Molecular Mechanisms in Mutant Trametes versicolor Strains with Enhanced Laccase Activities
by Chi Zhang, Zhongjie Yan, Xiufang Li, Junming Wang, Xidong Ren and Xinli Liu
Fermentation 2023, 9(12), 995; https://doi.org/10.3390/fermentation9120995 - 22 Nov 2023
Cited by 2 | Viewed by 1667
Abstract
The commercial potential of Trametes versicolor laccases in the degradation of various persistent contaminants is significant. Despite numerous attempts through rational metabolic engineering to enhance the properties of laccases, the outcomes have proven unsatisfactory for practical implementation. The present study successfully generated two [...] Read more.
The commercial potential of Trametes versicolor laccases in the degradation of various persistent contaminants is significant. Despite numerous attempts through rational metabolic engineering to enhance the properties of laccases, the outcomes have proven unsatisfactory for practical implementation. The present study successfully generated two novel mutants, namely, TA-04 and TA-15, derived from Trametes versicolor ATCC20869, utilizing atmospheric and room temperature plasma (ARTP). The laccase activities of TA-04 and TA-15 showed a significant increase to 136.507 ± 4.827 U/mg DCW and 153.804 ± 6.884 U/mg DCW, respectively, which were 1.201 and 1.354 times than that of the original strain. The laccase activities of the mutant strains TA-04 and TA-15 surpassed that of the original strain by 10.372% and 18.914%, respectively, at a higher pH level of five. Sequencing analysis of TA-04 and TA-15 revealed that several alternative amino acids within their active regions may enhance their catalytic characteristics under a higher temperature and pH condition. This study employed ARTP mutagenesis to propose two highly efficient microbial mutants derived from Trametes versicolor ATCC20869, exhibiting enhanced laccase activities. These mutants hold promising potential for the degradation of diverse environmental pollutants. Full article
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20 pages, 3940 KiB  
Article
Design-of-Experiment-Guided Establishment of a Fermentative Bioprocess for Biomass-Bound Astaxanthin with Corynebacterium glutamicum
by Florian Meyer, Ina Schmitt, Thomas Schäffer, Volker F. Wendisch and Nadja A. Henke
Fermentation 2023, 9(11), 969; https://doi.org/10.3390/fermentation9110969 - 11 Nov 2023
Cited by 1 | Viewed by 2265
Abstract
Corynebacterium glutamicum is prominent in the industrial production of secreted amino acids. Notably, it naturally accumulates the carotenoid pigment decaprenoxanthin in its membranes. Metabolic engineering enabled the production of astaxanthin. Here, a bioprocess for astaxanthin production in lab-scale stirred bioreactors was established by [...] Read more.
Corynebacterium glutamicum is prominent in the industrial production of secreted amino acids. Notably, it naturally accumulates the carotenoid pigment decaprenoxanthin in its membranes. Metabolic engineering enabled the production of astaxanthin. Here, a bioprocess for astaxanthin production in lab-scale stirred bioreactors was established by a DoE-guided approach to optimize the basic process parameters pH, rDOS, aeration rate as well as inoculation cell density. The DoE-guided approach to characterize 2 L scale cultivation revealed that the pH showed the strongest effect on the product formation. Subsequently, an optimum at pH 8, an aeration rate of 0.25 vvm, 30% rDOS and an initial optical density of 1 was established that allowed production of 7.6 ± 0.6 mg L−1 astaxanthin in batch mode. These process conditions were successfully transferred to a fed-batch process resulting in a high cell density cultivation with up to 60 g CDW L−1 biomass and 64 mg L−1 astaxanthin and thus demonstrating an about 9-fold improvement compared to optimal batch conditions. Moreover, pH-shift experiments indicate that the cells can quickly adapt to a change from pH 6 to 8 and start producing astaxanthin, showing the possibility of biphasic bioprocesses for astaxanthin production. Full article
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21 pages, 2517 KiB  
Article
Co-Fermentation of Glucose–Xylose–Cellobiose–XOS Mixtures Using a Synthetic Consortium of Recombinant Saccharomyces cerevisiae Strains
by Ning Yan, Tao Luan, Mengqi Yin, Yaping Niu, Longhao Wu, Shuo Yang, Zailu Li, Hongxing Li, Jianzhi Zhao and Xiaoming Bao
Fermentation 2023, 9(8), 775; https://doi.org/10.3390/fermentation9080775 - 19 Aug 2023
Cited by 1 | Viewed by 1665
Abstract
The efficient conversion of cellulosic sugars is vital for the economically viable production of biofuels/biochemicals from lignocellulosic biomass hydrolysates. Based on comprehensive screening, Saccharomyces cerevisiae RC212 was chosen as the chassis strain for multiple integrations of heterologous β-glucosidase and β-xylosidase genes in the [...] Read more.
The efficient conversion of cellulosic sugars is vital for the economically viable production of biofuels/biochemicals from lignocellulosic biomass hydrolysates. Based on comprehensive screening, Saccharomyces cerevisiae RC212 was chosen as the chassis strain for multiple integrations of heterologous β-glucosidase and β-xylosidase genes in the present study. The resulting recombinant BLN26 and LF1 form a binary synthetic consortium, and this co-culture system achieved partial fermentation of four sugars (glucose, xylose, cellobiose, and xylo-oligosaccharides). Then, we developed a ternary S. cerevisiae consortium consisting of LF1, BSGIBX, and 102SB. Almost all four sugars were efficiently fermented to ethanol within 24 h, and the ethanol yield is 0.482 g g−1 based on the consumed sugar. To our knowledge, this study represents the first exploration of the conversion of mixtures of glucose, xylose, cellobiose, and xylo-oligosaccharides by a synthetic consortium of recombinant S. cerevisiae strains. This synthetic consortium and subsequent improved ones have the potential to be used as microbial platforms to produce a wide array of biochemicals from lignocellulosic hydrolysates. Full article
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11 pages, 3070 KiB  
Communication
Biosynthesis of Glucaric Acid by Recombinant Strain of Escherichia coli Expressing Two Different Urinate Dehydrogenases
by Xinchao Yang, Linlin Niu, Chunjiang Ye, Yuanxiu Wang, Yuehui Liu, Fang Wang and Naxin Sun
Fermentation 2023, 9(8), 764; https://doi.org/10.3390/fermentation9080764 - 17 Aug 2023
Viewed by 1805
Abstract
D-glucaric acid is an important bio-based building block of polymers and is a high value-added chemical that can be used in a variety of applications. In the present study, the Udh target genes from Pseudomonas putida and Pseudomonas syringae were used together to [...] Read more.
D-glucaric acid is an important bio-based building block of polymers and is a high value-added chemical that can be used in a variety of applications. In the present study, the Udh target genes from Pseudomonas putida and Pseudomonas syringae were used together to construct the expression vector pETDuet-2 × Udh. The transformants of BL21 (DE3) with vector pETDuet-2 × Udh were applied to produce glucaric acid from glucuronic acid. After optimizing the induction conditions, the highest Udh expression was achieved when 0.4 mmol·L−1 isopropyl-β-d–thiogalactoside (IPTG) was added to the cell cultures at an OD600 value of 0.6 followed by culturing at 26 °C for 6 h. The production of glucaric acid substantially reached 5.24 ± 0.015 g·L−1 in fed-batch cultures in a 30 L tank. In the present study, a new system for glucaric acid production was established, which was more economic and friendly to the environment. Full article
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18 pages, 3100 KiB  
Article
High-Efficient Production of Cellulosic Ethanol from Corn Fiber Based on the Suitable C5/C6 Co-Fermentation Saccharomyces cerevisiae Strain
by Menglei Li, Fadi Xu, Yuping Zhao, Dongming Sun, Jiao Liu, Xiaolong Yin, Zailu Li, Jianzhi Zhao, Hongxing Li and Xiaoming Bao
Fermentation 2023, 9(8), 743; https://doi.org/10.3390/fermentation9080743 - 9 Aug 2023
Cited by 3 | Viewed by 2073
Abstract
As a potential alternative to fossil-based fuels, cellulosic ethanol has attracted much attention due to its great benefit to energy sustainability and environmental friendliness. However, at present, the industrial competitiveness of cellulosic ethanol production is still insufficient compared with fossil-based fuels because of [...] Read more.
As a potential alternative to fossil-based fuels, cellulosic ethanol has attracted much attention due to its great benefit to energy sustainability and environmental friendliness. However, at present, the industrial competitiveness of cellulosic ethanol production is still insufficient compared with fossil-based fuels because of the higher costs. Expanding the range of lignocellulosic biomass may be a promising measure to promote the economical production of cellulosic ethanol. Corn fiber, a byproduct from the corn deep-processing, is an attractive feedstock for cellulosic ethanol production because of its rich carbohydrate content (generally exceeding 65% of dry weight), almost no transportation cost, and low lignin content allow it to be easily handled. This study first optimized the hydrolysis conditions, including the pretreatment and enzymolysis process based on dilute sulfuric acid, to achieve a high sugar yield. Then, the corn fiber hydrolysates obtained under different hydrolysis conditions were suitably fermented by different C5/C6 co-fermentation Saccharomyces cerevisiae, indicating that the hydrolysate at high solid loading (20%) needs to detoxification to a certain extent but not low solid loading (10%) to achieve high ethanol yield. Finally, the fermentation of the 20% solid loading hydrolysates with resin detoxification was performed in a 50 L bioreactor, achieving the sugar (glucose and xylose) metabolic rate of 2.24 g L −1 h −1 and ethanol yield of 92% of the theoretical value, which are the highest reported levels to date. This study provided a potential process route for cellulosic ethanol production from corn fiber from the perspective of the suitability between the upstream hydrolysis process and the downstream fermentation strain. Full article
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12 pages, 2415 KiB  
Article
Improvement of ε-Poly-l-lysine Production by Co-Culture Fermentation Strategy
by Long Pan, Cunjin Zhang, Xinyu Yuan, Yu Zhang, Xusheng Chen, Cuizhu Tian, Zishan Zhang, Mengqing Tian, Aimei Liao, Guanghai Yu, Ming Hui, Xin Zeng and Jihong Huang
Fermentation 2023, 9(7), 626; https://doi.org/10.3390/fermentation9070626 - 30 Jun 2023
Cited by 3 | Viewed by 1723
Abstract
ε-poly-l-lysine (ε-PL) has been routinely used as a natural and safe preservative for many years in the food industry. However, most existing production methods struggle to achieve low cost and high production simultaneously. In this work, we present a co-culture fermentation [...] Read more.
ε-poly-l-lysine (ε-PL) has been routinely used as a natural and safe preservative for many years in the food industry. However, most existing production methods struggle to achieve low cost and high production simultaneously. In this work, we present a co-culture fermentation strategy to enhance ε-PL production. Specifically, we screened a strain from five different strains that could be co-cultured with Streptomyces albulus to raise the production of ε-PL. Subsequently, a single factor experiment and response surface design were used to optimize the conditions of co-culture fermentation to further improve the production of ε-PL. Moreover, the optimal fermentation process was successfully verified in a 2-L fermentor with fed batch fermentation. The production of ε-PL reached 27.07 ± 0.47 g/L by 144 h. Compared with single strain (S. albulus) fermentation, the production of ε-PL was increased by 31.47%. At the same time, the amount of bacteria increased by 19.62%, which means that the ε-PL synthesis ability of bacteria had been improved. All the obtained results showed great potential for co-culture fermentation in large-scale ε-PL production and provide a new fermentation strategy for ε-PL biosynthesis. Full article
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14 pages, 2242 KiB  
Article
Comparison of Raspberry Ketone Production via Submerged Fermentation in Different Bioreactors
by Yi Zhang, Eric Charles Peterson, Yuen Ling Ng, Kheng-Lim Goh, Vladimir Zivkovic and Yvonne Chow
Fermentation 2023, 9(6), 546; https://doi.org/10.3390/fermentation9060546 - 6 Jun 2023
Cited by 2 | Viewed by 2162
Abstract
Raspberry ketone (RK) has high commercial value in the food and healthcare industries. A biological route to this flavour compound is an attractive prospect, considering the need to meet consumer demands and sustainable goals; however, it is yet to become an industrial reality. [...] Read more.
Raspberry ketone (RK) has high commercial value in the food and healthcare industries. A biological route to this flavour compound is an attractive prospect, considering the need to meet consumer demands and sustainable goals; however, it is yet to become an industrial reality. In this work, fungal production of raspberry ketone (RK) and raspberry compounds (RC) via submerged fermentation of Nidula niveo-tomentosa was characterized in flask, stirred-tank reactor (STR), panel bioreactor (PBR), and fluidized bed reactor (FBR) configurations. The results indicate that the panel bioreactor resulted in larger, floccose pellets accompanied by maximum titres of 20.6 mg/L RK and 50.9 mg/L RC. The stirred-tank bioreactor with impeller mixing yielded compact elliptical pellets, induced the highest volumetric productivity of 2.0 mg L−1 day−1, and showed RK selectivity of 0.45. While differing mixing strategies had clear effects on pellet morphology, RK production presented a more direct positive relationship with cultivation conditions, and showed appropriate mixing and aeration favour RK to raspberry alcohol (RA). Overall, this paper highlights the importance of bioreactor design to fungal fermentation, and gives insight into green and industrial bioproduction of value-added natural compounds. Full article
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Review

Jump to: Research

9 pages, 526 KiB  
Review
The Application of Corynebacterium glutamicum in l-Threonine Biosynthesis
by Min Duan, Shuo Chen, Xinli Liu, Jianhang Liu and Deqiang Zhu
Fermentation 2023, 9(9), 822; https://doi.org/10.3390/fermentation9090822 - 8 Sep 2023
Cited by 6 | Viewed by 2632
Abstract
l-threonine is an essential amino acid in human and animal nutrition. It is widely used in food, medicine, feed, and other fields. The global market scale exceeds 700,000 tons per year. Corynebacterium glutamicum, as a chassis cell for industrial amino acid [...] Read more.
l-threonine is an essential amino acid in human and animal nutrition. It is widely used in food, medicine, feed, and other fields. The global market scale exceeds 700,000 tons per year. Corynebacterium glutamicum, as a chassis cell for industrial amino acid production, has the advantages of biological safety and strong environmental adaptability, and is a potential strain for the efficient production of l-threonine. This article systematically reviewed the function and application of l-threonine, the pathway of C. glutamicum to synthesize l-threonine, and the use of metabolic engineering technology to improve the production of l-threonine. Full article
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