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Effect of Adding Bifidobacterium animalis BZ25 on the Flavor, Functional Components and Biogenic Amines of Natto by Bacillus subtilis GUTU09. Foods 2022; 11:foods11172674. [PMID: 36076859 PMCID: PMC9455604 DOI: 10.3390/foods11172674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/25/2022] [Accepted: 08/27/2022] [Indexed: 11/17/2022] Open
Abstract
Natto is a high-value fermented soybean produced by B. subtilis. However, B. subtilis produces a pungent amine odor. This study compared the volatile organic compounds (VOCs), free amino acids (FAAs) and biogenic amines (BAs), nattokinase (NK) of natto made by two-strain fermentation with Bifidobacterium animalis BZ25 and Bacillus subtilis GUTU09 (NMBB) and that of natto made by single-strain fermentation with Bacillus subtilis GUTU09 (NMB). Compared with NMB, volatile amine substances disappeared, ketones and aldehydes of NMBB were reduced, and alcohols increased. Besides that, the taste activity value of other bitter amino acids was lowered, and BA content was decreased from 255.88 mg/kg to 238.35 mg/kg but increased NK activity from 143.89 FU/g to 151.05 FU/g. Correlation analysis showed that the addition of BZ25 reduced the correlation between GUTU09 and BAs from 0.878 to 0.808, and pH was changed from a positive correlation to a negative one. All these results showed that the quality of natto was improved by two-strain co-fermentation, which laid a foundation for its potential industrial application.
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Heterologous expression of nattokinase from B. subtilis natto using Pichia pastoris GS115 and assessment of its thrombolytic activity. BMC Biotechnol 2021; 21:49. [PMID: 34372833 PMCID: PMC8353737 DOI: 10.1186/s12896-021-00708-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 07/14/2021] [Indexed: 11/10/2022] Open
Abstract
Background Nattokinase is a fibrinolytic enzyme that has huge market value as a nutritional supplement for health promotion. In order to increase nattokinase yields, fermentation conditions, strains, cultivation media, and feeding strategies have been optimized. Nattokinase has been expressed using several heterologous expression systems. Pichia pastoris heterologous expression system was the alternative. Results This report aimed to express high levels of nattokinase from B. subtilis natto (NK-Bs) using a Pichia pastoris heterologous expression system and assess its fibrinolytic activity in vivo. Multicopy expression strains bearing 1–7 copies of the aprN gene were constructed. The expression level of the target protein reached a maximum at five copies of the target gene. However, multicopy expression strains were not stable in shake-flask or high-density fermentation, causing significant differences in the yield of the target protein among batches. Therefore, P. pastoris bearing a single copy of aprN was used in shake-flask and high-density fermentation. Target protein yield was 320 mg/L in shake-flask fermentation and approximately 9.5 g/L in high-density fermentation. The recombinant nattokinase showed high thermo- and pH-stability. The present study also demonstrated that recombinant NK-Bs had obvious thrombolytic activity. Conclusions This study suggests that the P. pastoris expression system is an ideal platform for the large-scale, low-cost preparation of nattokinase. Supplementary Information The online version contains supplementary material available at 10.1186/s12896-021-00708-4.
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Yao Z, Meng Y, Le HG, Lee SJ, Jeon HS, Yoo JY, Kim JH. Increase of a Fibrinolytic Enzyme Production through Promoter Replacement of aprE3-5 from Bacillus subtilis CH3-5. J Microbiol Biotechnol 2021; 31:833-839. [PMID: 33958509 PMCID: PMC9705994 DOI: 10.4014/jmb.2103.03027] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/03/2021] [Accepted: 05/06/2021] [Indexed: 12/15/2022]
Abstract
Bacillus subtilis CH3-5 isolated from cheonggukjang secretes a 28 kDa protease with a strong fibrinolytic activity. Its gene, aprE3-5, was cloned and expressed in a heterologous host (Jeong et al., 2007). In this study, the promoter of aprE3-5 was replaced with other stronger promoters (Pcry3A, P10, PSG1, PsrfA) of Bacillus spp. using PCR. The constructed chimeric genes were cloned into pHY300PLK vector, and then introduced into B. subtilis WB600. The P10 promoter conferred the highest fibrinolytic activity, i.e., 1.7-fold higher than that conferred by the original promoter. Overproduction of the 28 kDa protease was confirmed using SDS-PAGE and fibrin zymography. RT-qPCR analysis showed that aprE3-5 expression was 2.0-fold higher with the P10 promoter than with the original promoter. Change of the initiation codon from GTG to ATG further increased the fibrinolytic activity. The highest aprE3-5 expression was observed when two copies of the P10 promoter were placed in tandem upstream of the ATG initiation codon. The construct with P10 promoter and ATG and the construct with two copies of P10 promoter in tandem and ATG exhibited 117% and 148% higher fibrinolytic activity, respectively, than that exhibited by the construct containing P10 promoter and GTG. These results confirmed that significant overproduction of a fibrinolytic enzyme can be achieved by suitable promoter modification, and this approach may have applications in the industrial production of AprE3-5 and related fibrinolytic enzymes.
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Affiliation(s)
- Zhuang Yao
- Division of Applied Life Science (BK21 Four), Graduate School, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Yu Meng
- Division of Applied Life Science (BK21 Four), Graduate School, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Huong Giang Le
- Division of Applied Life Science (BK21 Four), Graduate School, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Se Jin Lee
- Division of Applied Life Science (BK21 Four), Graduate School, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Hye Sung Jeon
- Division of Applied Life Science (BK21 Four), Graduate School, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Ji Yeon Yoo
- Division of Applied Life Science (BK21 Four), Graduate School, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Jeong Hwan Kim
- Division of Applied Life Science (BK21 Four), Graduate School, Gyeongsang National University, Jinju 52828, Republic of Korea,Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Republic of Korea,Corresponding author Phone: +82- 55-772-1904 Fax: +82-55-772-1909 E-mail :
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Production of proteins and commodity chemicals using engineered Bacillus subtilis platform strain. Essays Biochem 2021; 65:173-185. [PMID: 34028523 DOI: 10.1042/ebc20210011] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 05/02/2021] [Accepted: 05/06/2021] [Indexed: 12/19/2022]
Abstract
Currently, increasing demand of biochemicals produced from renewable resources has motivated researchers to seek microbial production strategies instead of traditional chemical methods. As a microbial platform, Bacillus subtilis possesses many advantages including the generally recognized safe status, clear metabolic networks, short growth cycle, mature genetic editing methods and efficient protein secretion systems. Engineered B. subtilis strains are being increasingly used in laboratory research and in industry for the production of valuable proteins and other chemicals. In this review, we first describe the recent advances of bioinformatics strategies during the research and applications of B. subtilis. Secondly, the applications of B. subtilis in enzymes and recombinant proteins production are summarized. Further, the recent progress in employing metabolic engineering and synthetic biology strategies in B. subtilis platform strain to produce commodity chemicals is systematically introduced and compared. Finally, the major limitations for the further development of B. subtilis platform strain and possible future directions for its research are also discussed.
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Li M, Zhang Z, Li S, Tian Z, Ma X. Study on the mechanism of production of γ-PGA and nattokinase in Bacillus subtilis natto based on RNA-seq analysis. Microb Cell Fact 2021; 20:83. [PMID: 33836770 PMCID: PMC8034199 DOI: 10.1186/s12934-021-01570-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/25/2021] [Indexed: 11/10/2022] Open
Abstract
Poly-γ-glutamic acid (γ-PGA) and nattokinase (NK) are the main substances produced by Bacillus subtilis natto in solid-state fermentation and have wide application prospects. We found that our strains had higher activity of nattokinase when soybeans were used as substrate to increase the yield of γ-PGA. Commercial production of γ-PGA and nattokinase requires an understanding of the mechanism of co-production. Here, we obtained the maximum γ-PGA yield (358.5 g/kg, w/w) and highest activity of NK during fermentation and analyzed the transcriptome of Bacillus subtilis natto during co-production of γ-PGA and NK. By comparing changes in expression of genes encoding key enzymes and the metabolic pathways associated with the products in genetic engineering, the mechanism of co-production of γ-PGA and nattokinase can be summarized based on RNA-seq analysis. This study firstly provides new insights into the mechanism of co-production of γ-PGA and nattokinase by Bacillus subtilis natto and reveals potential molecular targets to promote the co-production of γ-PGA and nattokinase.
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Affiliation(s)
- Min Li
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Shanghai, 201418, China
| | - Zilong Zhang
- Shanghai International Travel Healthcare Center, Shanghai Customs District P. R, Shanghai, 200335, China
| | - Shenwei Li
- Shanghai International Travel Healthcare Center, Shanghai Customs District P. R, Shanghai, 200335, China
| | - Zhengan Tian
- Shanghai International Travel Healthcare Center, Shanghai Customs District P. R, Shanghai, 200335, China.
| | - Xia Ma
- School of Perfume and Aroma Technology, Shanghai Institute of Technology, Shanghai, 201418, China. .,State Key Laboratory of Dairy Biotechnology, Shanghai Engineering Research Center of Dairy Biotechnology, Dairy Research Institute, Bright Dairy and Food Co., Ltd, Shanghai, 200436, China.
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Isolation and Optimal Fermentation Condition of the Bacillus subtilis Subsp. natto Strain WTC016 for Nattokinase Production. FERMENTATION-BASEL 2019. [DOI: 10.3390/fermentation5040092] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Nattokinase is a serine protease in the subtilisin family which is produced by Bacillus subtilis subsp. natto and exhibits vigorous fibrinolytic activity that has been suggested to be able to prevent and treat thromboembolic diseases. In this study, WTC016, a spore-forming and rod-shaped bacterium with fibrinolytic activity was successfully isolated from soil, which was identified as Bacillus subtilis subsp. natto based on morphological and physiological tests, and phylogenetic analysis of 16S rRNA and gyrA. According to the growth curve of WTC016, the nattokinase production reached the highest amount in the stationary phase. To optimize the liquid fermentation condition for nattokinase yield of WTC016, further optimal tests of four factors, including the temperature, pH, inoculum size, and loading volume, followed by orthogonal test of all these factors, was performed. The optimal fermentation conditions were determined as 30 °C, 7.0 pH, 2% inoculum size, and 60 mL of loading volume in 250 mL conical flask, which indicates the highest nattokinase production of 3284 ± 58 IU/mL while fermented for 26 h. This work laid the foundation for producing nattokinase using Bacillus subtilis subsp. natto WTC016.
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Averesch NJH, Rothschild LJ. Metabolic engineering of Bacillus subtilis for production of para-aminobenzoic acid - unexpected importance of carbon source is an advantage for space application. Microb Biotechnol 2019; 12:703-714. [PMID: 30980511 PMCID: PMC6559200 DOI: 10.1111/1751-7915.13403] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/08/2019] [Accepted: 03/08/2019] [Indexed: 01/28/2023] Open
Abstract
High-strength polymers, such as aramid fibres, are important materials in space technology. To obtain these materials in remote locations, such as Mars, biological production is of interest. The aromatic polymer precursor para-aminobenzoic acid (pABA) can be derived from the shikimate pathway through metabolic engineering of Bacillus subtilis, an organism suited for space synthetic biology. Our engineering strategy included repair of the defective indole-3-glycerol phosphate synthase (trpC), knockout of one chorismate mutase isozyme (aroH) and overexpression of the aminodeoxychorismate synthase (pabAB) and aminodeoxychorismate lyase (pabC) from the bacteria Corynebacterium callunae and Xenorhabdus bovienii respectively. Further, a fusion-protein enzyme (pabABC) was created for channelling of the carbon flux. Using adaptive evolution, mutants of the production strain, able to metabolize xylose, were created, to explore and compare pABA production capacity from different carbon sources. Rather than the efficiency of the substrate or performance of the biochemical pathway, the product toxicity, which was strongly dependent on the pH, appeared to be the overall limiting factor. The highest titre achieved in shake flasks was 3.22 g l-1 with a carbon yield of 12.4% [C-mol/C-mol] from an amino sugar. This promises suitability of the system for in situ resource utilization (ISRU) in space biotechnology, where feedstocks that can be derived from cyanobacterial cell lysate play a role.
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Affiliation(s)
- Nils J. H. Averesch
- Universities Space Research AssociationMountain ViewCA94043USA
- NASA Ames Research CenterMoffett FieldCA94035USA
- Present address:
Stanford UniversityStanfordCA94305USA
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Liu Z, Zheng W, Ge C, Cui W, Zhou L, Zhou Z. High-level extracellular production of recombinant nattokinase in Bacillus subtilis WB800 by multiple tandem promoters. BMC Microbiol 2019; 19:89. [PMID: 31064343 PMCID: PMC6505213 DOI: 10.1186/s12866-019-1461-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 04/18/2019] [Indexed: 01/24/2023] Open
Abstract
Background Nattokinase (NK), which is a member of the subtilisin family, is a potent fibrinolytic enzyme that might be useful for thrombosis therapy. Extensive work has been done to improve its production for the food industry. The aim of our study was to enhance NK production by tandem promoters in Bacillus subtilis WB800. Results Six recombinant strains harboring different plasmids with a single promoter (PP43, PHpaII, PBcaprE, PgsiB, PyxiE or PluxS) were constructed, and the analysis of the fibrinolytic activity showed that PP43 and PHpaII exhibited a higher expression activity than that of the others. The NK yield that was mediated by PP43 and PHpaII reached 140.5 ± 3.9 FU/ml and 110.8 ± 3.6 FU/ml, respectively. These promoters were arranged in tandem to enhance the expression level of NK, and our results indicated that the arrangement of promoters in tandem has intrinsic effects on the NK expression level. As the number of repetitive PP43 or PHpaII increased, the expression level of NK was enhanced up to the triple-promoter, but did not increase unconditionally. In addition, the repetitive core region of PP43 or PHpaII could effectively enhance NK production. Eight triple-promoters with PP43 and PHpaII in different orders were constructed, and the highest yield of NK finally reached 264.2 ± 7.0 FU/ml, which was mediated by the promoter PHpaII-PHpaII-PP43. The scale-up production of NK that was promoted by PHpaII-PHpaII-PP43 was also carried out in a 5-L fermenter, and the NK activity reached 816.7 ± 30.0 FU/mL. Conclusions Our studies demonstrated that NK was efficiently overproduced by tandem promoters in Bacillus subtilis. The highest fibrinolytic activity was promoted by PHpaII-PHpaII-PP43, which was much higher than that had been reported in previous studies. These multiple tandem promoters were used successfully to control NK expression and might be useful for improving the expression level of the other genes. Electronic supplementary material The online version of this article (10.1186/s12866-019-1461-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zhongmei Liu
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China.
| | - Wenhui Zheng
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Chunlei Ge
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Wenjing Cui
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Li Zhou
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China
| | - Zhemin Zhou
- Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122, Jiangsu, China.
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Pan S, Chen G, Zeng J, Cao X, Zheng X, Zeng W, Liang Z. Fibrinolytic enzyme production from low-cost substrates by marine Bacillus subtilis: Process optimization and kinetic modeling. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2018.11.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Pandey R, Kumar N, Monteiro GA, Veeranki VD, Prazeres DMF. Re-engineering of an Escherichia coli K-12 strain for the efficient production of recombinant human Interferon Gamma. Enzyme Microb Technol 2018; 117:23-31. [PMID: 30037548 DOI: 10.1016/j.enzmictec.2018.06.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/23/2018] [Accepted: 06/03/2018] [Indexed: 01/17/2023]
Abstract
The Escherichia coli phosphoglucose isomerase (pgi) mutant strain GALG20 was developed previously from wild-type K12 strain MG1655 for increased plasmid yield. To investigate the potential effects of the pgi deletion/higher plasmid levels on recombinant human Interferon Gamma (IFN-γ) production, a detailed network of the central metabolic pathway (100 metabolites, 114 reactions) of GALG20 and MG1655 was constructed. Elementary mode analysis (EMA) was then performed to compare the phenotypic spaces of both the strains and to check the effect of the pgi deletion on flux efficiency of each metabolic reaction. The results suggested that pgi deletion increases amino acid biosynthesis and flux efficiency towards IFN-γ synthesis by 11%. To further confirm the qualitative prediction that the pgi mutation favours recombinant human IFN-γ expression, GALG20 and MG1655 were lysogenised, transformed with a plasmid coding for IFN-γ and tested alongside with BL21(DE3) for their expression capabilities in shake flask experiments using complex media. IFN-γ gene expression was analysed by quantifying plasmid and mRNA copy number per cell and IFN-γ protein production level. Specific IFN-γ yields confirmed the in silico metabolic network predictions, with GALG20(DE3) producing 3.0-fold and 1.5-fold more IFN-γ as compared to MG1655(DE3) and BL21(DE3), respectively. Most of the total IFN-γ was expressed as inclusion bodies across the three strains: 95% in GALG20(DE3), 97% in BL21(DE3) and 72% in MG1655(DE3). The copy number of mRNA coding for IFN-γ was found to be higher in GALG20(DE3) as compared to the other two strains. Overall, these findings show that GALG20(DE3) has the potential to become an excellent protein expression strain.
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Affiliation(s)
- Rajat Pandey
- iBB-Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Lisbon 1049-001, Portugal; Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, India.
| | - Nitin Kumar
- iBB-Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Lisbon 1049-001, Portugal; Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - Gabriel A Monteiro
- iBB-Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Lisbon 1049-001, Portugal
| | - Venkata Dasu Veeranki
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, India
| | - D M F Prazeres
- iBB-Institute for Bioengineering and Biosciences, Department of Bioengineering, Instituto Superior Técnico, Lisbon 1049-001, Portugal
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Microbial production of nattokinase: current progress, challenge and prospect. World J Microbiol Biotechnol 2017; 33:84. [DOI: 10.1007/s11274-017-2253-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 03/28/2017] [Indexed: 12/19/2022]
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Nattokinase: production and application. Appl Microbiol Biotechnol 2014; 98:9199-206. [DOI: 10.1007/s00253-014-6135-3] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Revised: 09/30/2014] [Accepted: 10/04/2014] [Indexed: 11/28/2022]
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Singh S, Moholkar VS, Goyal A. Optimization of carboxymethylcellulase production from Bacillus amyloliquefaciens SS35. 3 Biotech 2014; 4:411-424. [PMID: 28324477 PMCID: PMC4145630 DOI: 10.1007/s13205-013-0169-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Accepted: 08/26/2013] [Indexed: 11/21/2022] Open
Abstract
In this paper, we have attempted optimization of production of enzyme carboxymethylcellulase or endoglucanase from the bacterium Bacillus amyloliquefaciens SS35. Optimization has been carried out in two stages using statistical experimental design, viz. medium optimization and optimization of fermentation parameters. For medium optimization, Plackett–Burman design followed by central composite design (CCD) was used, while for optimization of fermentation parameters one-variable-at-a-time method followed by CCD was used. Carbon and nitrogen sources in the medium have been revealed to be the significant factors for enzyme production (carboxymethylcellulose 18.05 g/L; yeast extract 8 g/L and peptone 2 g/L). The inorganic salts have been found to be insignificant components of medium. Optimum fermentation parameters for optimized medium were: initial medium pH 5.65, incubation temperature = 40 °C, shaking speed = 120 rpm, and inoculum size = 6.96 %, v/v. Interestingly, the influence of all four parameters was almost independent with no interlinks. Secondly, the overall effect of all parameters was also low, as indicated by linear, square and interaction regression coefficients that were at least one order of magnitude lower than the intercept in the model equation. These results essentially meant that medium components dominate overall enzyme production process in comparison to fermentation parameters.
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Suwanmanon K, Hsieh PC. IsolatingBacillus subtilisand optimizing its fermentative medium for GABA and nattokinase production. CYTA - JOURNAL OF FOOD 2013. [DOI: 10.1080/19476337.2013.848472] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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