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Ebrahimzadeh Kouchesfahani M, Bahrami A, Babaeipour V. Poly-γ-glutamic acid overproduction of Bacillus licheniformis ATCC 9945 a by developing a novel optimum culture medium and glutamate pulse feeding using different experimental design approaches. Biotechnol Appl Biochem 2024; 71:565-583. [PMID: 38246886 DOI: 10.1002/bab.2559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 12/31/2023] [Indexed: 01/23/2024]
Abstract
The commercial production of multifunctional, biocompatible, and biodegradable biopolymers such as poly-γ-glutamic acid via microbial fermentation requires the development of simple and cheap methods for mass production. This study optimized the poly-γ-glutamic acid production of Bacillus licheniformis ATCC 9945a in several steps. At first, the most critical components of the culture medium, including l-glutamic acid, citric acid, and glycerol, were selected by screening nine factors through the Plackett-Burman experimental design and then were optimized using the response surface method and the central composite design algorithm. Under optimal conditions, the production of poly-γ-glutamic acid increased by more than 4.2 times from 11.2 to 47.2 g/L. This is one of the highest production rates of this strain in submerged batch fermentation reported so far using the optimized medium compared to the conventional base medium. A novel and efficient sudden pulse feeding strategy (achieved by a novel one-factorial statistical technique) of l-glutamic acid to the optimized medium increased biopolymer production from 47.2 to 66.1 g/L, the highest value reported in published literature with this strain. This simple, reproducible, and cheap fermentation process can considerably enhance the commercial applications of the poly-γ-glutamic acid synthesized by B. licheniformis ATCC 9945a.
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Affiliation(s)
| | - Ali Bahrami
- Faculty of Chemistry and Chemical Engineering, Malek Ashtar University of Technology, Tehran, Iran
| | - Valiollah Babaeipour
- Faculty of Chemistry and Chemical Engineering, Malek Ashtar University of Technology, Tehran, Iran
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Kaur A, Soni SK, Vij S, Rishi P. Cocktail of carbohydrases from Aspergillus niger: an economical and eco-friendly option for biofilm clearance from biopolymer surfaces. AMB Express 2021; 11:22. [PMID: 33538938 PMCID: PMC7862497 DOI: 10.1186/s13568-021-01183-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 01/18/2021] [Indexed: 11/25/2022] Open
Abstract
Biofilm formation on both biotic and abiotic surfaces accounts for a major factor in spread of antimicrobial resistance. Due to their ubiquitous nature, biofilms are of great concern for environment as well as human health. In the present study, an integrated process for the co-production of a cocktail of carbohydrases from a natural variant of Aspergillus niger was designed. The enzyme cocktail was found to have a noteworthy potential to eradicate/disperse the biofilms of selected pathogens. For application of enzymes as an antibiofilm agent, the enzyme productivities were enhanced by statistical modelling using response surface methodology (RSM). The antibiofilm potential of the enzyme cocktail was studied in terms of (i) in vitro cell dispersal assay (ii) release of reducing sugars from the biofilm polysaccharides (iii) the effect of enzyme treatment on biofilm cells and architecture by confocal laser scanning microscopy (CLSM). Potential of the enzyme cocktail to disrupt/disperse the biofilm of selected pathogens from biopolymer surfaces was also assessed by field emission scanning electron microscopy (FESEM) analysis. Further, their usage in conjunction with antibiotics was assessed and it was inferred from the results that the use of enzyme cocktail augmented the efficacy of the antibiotics. The study thus provides promising insights into the prospect of using multiple carbohydrases for management of heterogeneous biofilms formed in natural and clinical settings.
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Affiliation(s)
- Arashdeep Kaur
- Department of Microbiology, Panjab University, Sector-25, Chandigarh, 160014, India
| | - Sanjeev Kumar Soni
- Department of Microbiology, Panjab University, Sector-25, Chandigarh, 160014, India
| | - Shania Vij
- Department of Microbiology, Panjab University, Sector-25, Chandigarh, 160014, India
| | - Praveen Rishi
- Department of Microbiology, Panjab University, Sector-25, Chandigarh, 160014, India.
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Fang J, Huan C, Liu Y, Xu L, Yan Z. Bioconversion of agricultural waste into poly-γ-glutamic acid in solid-state bioreactors at different scales. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 102:939-948. [PMID: 31855694 DOI: 10.1016/j.wasman.2019.12.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 11/11/2019] [Accepted: 12/10/2019] [Indexed: 06/10/2023]
Abstract
With the purpose of developing a novel approach of agricultural waste treatment and overcoming bottlenecks for upscaling solid-state fermentation processes, the type of aerated, continuously stirred solid-state bioreactors were used for the production of γ-PGA by Bacillus amyloliquefaciens JX-6. Using corn stalk and soybean meal, the most common agricultural waste in China, as solid substrates, the maximum production of γ-PGA was 116.88 ± 5.05 g/kg and 102.48 ± 3.30 g/kg in 50 L and 150 L bioreactors, respectively. Production of γ-PGA in 50 L bioreactor was higher than in 150 L bioreactor, demonstrating that a reduction in γ-PGA production occurred as the fermentation system enlarged. An analysis of the interactions among fermentation parameters (temperature, moisture, and pH), γ-PGA production, solid substrates and bacterial communities indicated that different bioreactor capacities caused changes in fermentation parameters and bacterial communities, which in turn affected substrate utilization and γ-PGA production. Overall, obtaining considerable amounts of γ-PGA under non-sterilized fermentation expressed that JX-6 has excellent abilities to adapt to these substrates and conditions. Bioconversion of agricultural waste into γ-PGA in scale-up fermentation was successfully conducted by creating a more stable and suitable fermentation environment in bioreactors.
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Affiliation(s)
- Junnan Fang
- University of Chinese Academy of Sciences, Beijing 100049, PR China; Key Laboratory of Environmental and Applied Microbiology, CAS, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China
| | - ChenChen Huan
- Key Laboratory of Environmental and Applied Microbiology, CAS, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China
| | - Yang Liu
- University of Chinese Academy of Sciences, Beijing 100049, PR China; Key Laboratory of Environmental and Applied Microbiology, CAS, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China
| | - Lishang Xu
- Key Laboratory of Environmental and Applied Microbiology, CAS, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China
| | - Zhiying Yan
- Key Laboratory of Environmental and Applied Microbiology, CAS, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, PR China.
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Poly-(γ-glutamic acid) Production and Optimization from Agro-Industrial Bioresources as Renewable Substrates by Bacillus sp. FBL-2 through Response Surface Methodology. Biomolecules 2019; 9:biom9120754. [PMID: 31756993 PMCID: PMC6995579 DOI: 10.3390/biom9120754] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 11/16/2019] [Accepted: 11/19/2019] [Indexed: 11/16/2022] Open
Abstract
We optimized culture conditions using Bacillus sp. FBL-2 as a poly-(γ-glutamic acid) (PGA) producing strain isolated from cheonggukjang. All experiments were performed under aerobic conditions using a laboratory scale 2.5 L fermentor. We investigated the effects of fermentation parameters (temperature, pH, agitation, and aeration) and medium components (glutamic acid, citric acid, and yeast extract) on poly-(γ-glutamic acid) production, viscosity, and dry cell mass. A non-optimized fermentation method (1.5 vvm, 350 rpm, and 37 °C) yielded PGA, viscosity, and dry cell mass at levels of 100.7 g/L, 483.2 cP, and 3.4 g/L, respectively. L-glutamic acid, citric acid, and yeast extract supplementation enhanced poly-(γ-glutamic acid) production to 175.9 g/L. Additionally, the production of poly-(γ-glutamic acid) from rice bran and wheat bran was assessed using response surface methodology (central composite rotatable design). Agricultural byproducts (rice bran and wheat bran) and H2SO4 were selected as factors, and experiments were performed by combining various component concentrations to determine optimal component concentrations. Our experimentally-derived optimal parameters included 38.6 g/L of rice bran, 0.42% of H2SO4, 28.0 g/L of wheat bran, and 0.32% of H2SO4. Under optimum conditions, rice bran medium facilitated poly-(γ-glutamic acid) production of up to 22.64 g/L, and the use of wheat bran medium yielded up to 14.6 g/L. Based on a validity test using the optimized culture conditions, poly-(γ-glutamic acid) was produced at 47.6 g/L and 36.4 g/L from these respective mediums, and both results were higher than statistically predicted. This study suggests that rice bran can be used as a potential alternative substrate for poly-(γ-glutamic acid) production.
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Optimization of γ-polyglutamic acid synthesis using response surface methodology of a newly isolated glutamate dependent Bacillus velezensis Z3. Int Microbiol 2019; 21:143-152. [PMID: 30810954 DOI: 10.1007/s10123-018-0011-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 05/22/2018] [Accepted: 05/28/2018] [Indexed: 10/14/2022]
Abstract
A new glutamate-dependent γ-polyglutamic acid (γ-PGA) producer Z3 isolated from soil samples in Daxinganling forest region of China was identified, and its optimal medium components were investigated using response surface methodology. Strain Z3 was identified as Bacillus velezensis by physiology and biochemistry and 16S rDNA sequence analysis. This is the first report of glutamate-dependent B. velezensis with the ability to synthesize γ-PGA. Then, the optimum γ-PGA yield (5.58 g/L) was achieved with glutamate 86 g/L, glucose 36 g/L, yeast extract powder 5.5 g/L, and NaH2PO4 7.5 g/L. Furthermore, activities of enzymes participating in glutamate synthesis were assessed, and the results showed that lower ketoglutaric dehydrogenase activity (KGDH) and higher glutamate dehydrogenase activity (GDH) resulted in higher γ-PGA yield. Identification of glutamate-dependent γ-PGA producer named B. velezensis Z3 enriches microbiological resources with γ-PGA-producing capacity. B. velezensis optimization of nutrients and analysis of enzymes activities will not only help to increase γ-PGA productivity but also to understand the γ-PGA synthesis mechanism in B. velezensis Z3.
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Nithya K, Muthukumar C, Kadaikunnan S, Alharbi NS, Khaled JM, Dhanasekaran D. Purification, characterization, and statistical optimization of a thermostable α-amylase from desert actinobacterium Streptomyces fragilis DA7-7. 3 Biotech 2017; 7:350. [PMID: 28955647 PMCID: PMC5614901 DOI: 10.1007/s13205-017-0981-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 09/14/2017] [Indexed: 11/29/2022] Open
Abstract
In this study, preliminary screening revealed that of 134 desert soil actinobacterial isolates, only 43 isolates produced amylase. Among these, an isolate DA7-7, which was identified as Streptomyces fragilis DA7-7, showed a prominent zone of clearance and significant amount of α-amylase production. The pre-optimization studies showed varying physicochemical and nutrients properties of the medium influenced the enzyme production significantly. Consequently, central composite design was employed with the selected variables (pH, temperature, dextrose, and peptone) for α-amylase production. The optimum fermentation conditions were 3.07% dextrose, 1.085% peptone, pH 6.0, and incubation temperature 27.27 °C. The predicted optimum α-amylase activity was 991.82 U/mL/min, which was similar to the experimental amylase activity of 973.5 U/mL/min. The crude α-amylase produced by S. fragilis DA7-7 was purified with ammonium sulfate precipitation, followed by gel filtration chromatography, and the estimated molecular mass was 51 kDa. The purified α-amylase was stable under the following conditions: pH (4-9), temperature (40-80 °C), NaCl (1-4 M), and detergents (1-10 mM). The Km and Vmax values of enzyme were found to be 0.624 mU/mg and 0.836 mg/mL, respectively.
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Affiliation(s)
- Krishnasamy Nithya
- Department of Microbiology, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu 620024 India
| | - Chinnasamy Muthukumar
- Department of Microbiology, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu 620024 India
| | - Shine Kadaikunnan
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451 Saudi Arabia
| | - Naiyf S. Alharbi
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451 Saudi Arabia
| | - Jamal M. Khaled
- Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451 Saudi Arabia
| | - Dharumadurai Dhanasekaran
- Department of Microbiology, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu 620024 India
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Liang JD, Han YF, Zhang JW, Du W, Liang ZQ, Li ZZ. Optimal culture conditions for keratinase production by a novel thermophilic Myceliophthora thermophila strain GZUIFR-H49-1. J Appl Microbiol 2015; 110:871-80. [PMID: 21241422 DOI: 10.1111/j.1365-2672.2011.04949.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS To investigate the effect of medium compositions and culture conditions on keratinase production by a novel thermophilic fungus Myceliophthora thermophila (Apinis) Oorschot strain GZUIFR-H49-1. METHODS AND RESULTS The thermophilic strain GZUIFR-H49-1 with keratinolytic ability was characterized and identified as a strain of M. thermophila on the basis of its morphological characters and molecular analysis of ITS1-5.8S-ITS2 rDNA sequence. Among the medium compositions tested, the soluble starch (SS), urea, sodium thiosulfate and CaCl2 were the most effective C-source, N-source, S-source and mineral ion, respectively, by employing the single-factor experiment. The urea and pH value were the significant factors (P < 0·05) for the keratinase production in this experiment condition using Plackett–Burman factorial design. The conditions of keratinase production were further optimized by Box–Behnken design. Consequently, there was a 6·4-fold increase (5100 U l−1) in the keratinase activity than the initial value (800 U l−1) by this optimal process. CONCLUSIONS This study indicated that the optimization design proved a useful and powerful tool for the development of optimal medium compositions and culture conditions. Myceliophthora thermophila strain GZUIFR-H49-1 was a promising fungus strain for keratinase production.
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Affiliation(s)
- J D Liang
- Institute of Fungus Resources, Guizhou University, Guiyang, China
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Wang J, Liu Z, Wang Y, Cheng W, Mou H. Production of a water-soluble fertilizer containing amino acids by solid-state fermentation of soybean meal and evaluation of its efficacy on the rapeseed growth. J Biotechnol 2014; 187:34-42. [PMID: 25062659 DOI: 10.1016/j.jbiotec.2014.07.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/10/2014] [Accepted: 07/12/2014] [Indexed: 01/31/2023]
Abstract
Soybean meal is a by-product of soybean oil extraction and contains approximately 44% protein. We performed solid-state fermentation by using Bacillus subtilis strain N-2 to produce a water-soluble fertilizer containing amino acids. Strain N-2 produced a high yield of protease, which transformed the proteins in soybean meal into peptide and free amino acids that were dissolved in the fermentation products. Based on the Plackett-Burman design, the initial pH of the fermentation substrate, number of days of fermentation, and the ratio of liquid to soybean meal exhibited significant effects on the recovery of proteins in the resulting water-soluble solution. According to the predicted results of the central composite design, the highest recovery of soluble proteins (99.072%) was achieved at the optimum conditions. Under these conditions, the resulting solution contained 50.42% small peptides and 7.9% poly-γ-glutamic acid (γ-PGA). The water-soluble fertilizer robustly increased the activity of the rapeseed root system, chlorophyll content, leaf area, shoot dry weight, root length, and root weight at a concentration of 0.25% (w/v). This methodology offers a value-added use of soybean meal.
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Affiliation(s)
- Jianlei Wang
- College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Zhemin Liu
- College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Yue Wang
- College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Wen Cheng
- College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Qingdao 266003, China
| | - Haijin Mou
- College of Food Science and Engineering, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
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He Y, Xu J, Wang S, Zhou G, Liu J. Optimization of medium components for production of chitin deacetylase by Bacillus amyloliquefaciens Z7, using response surface methodology. BIOTECHNOL BIOTEC EQ 2014; 28:242-247. [PMID: 26740755 PMCID: PMC4684075 DOI: 10.1080/13102818.2014.907659] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Accepted: 08/12/2013] [Indexed: 11/14/2022] Open
Abstract
Plackett-Burman design and Box-Behnken response surface methodology (RSM) was employed to optimize the medium components for the chitin deacetylase (CDA) activity from Bacillus amyloliquefaciens Z7. Plackett-Burman design was applied to determine the specific medium components affecting CDA activity and found that starch, chitin and MgSO4 were critical in augmenting CDA activity. These significant parameters were further optimized using Box-Behnken RSM and the optimum concentrations of starch, chitin and MgSO4 were found to be 24.4, 8.8 and 0.19 g/L, respectively. The optimum medium composition was chitin 8.8 g/L, starch 24.4 g/L, yeast extract 10g/L, MgSO4 0.19 g/L, K2HPO4 0.3 g/L and NaCl 5 g/L. Under these optimal conditions, the CDA activity of Bacillus amyloliquefaciens Z7 increased distinctly from 18.75 to 27.48 U/mL (46.6% increase in total yield).
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Affiliation(s)
- Yuanhao He
- Key Laboratory for Non-wood Forest Cultivation and Conservation of the Ministry of Education, Central South University of Forestry and Technology, Changsha, P.R. China
- College of Forestry, Central South University of Forestry and Technology, Changsha, P.R. China
| | - Jianping Xu
- Key Laboratory for Non-wood Forest Cultivation and Conservation of the Ministry of Education, Central South University of Forestry and Technology, Changsha, P.R. China
- College of Forestry, Central South University of Forestry and Technology, Changsha, P.R. China
| | - Shengjie Wang
- Key Laboratory for Non-wood Forest Cultivation and Conservation of the Ministry of Education, Central South University of Forestry and Technology, Changsha, P.R. China
- College of Forestry, Central South University of Forestry and Technology, Changsha, P.R. China
| | - Guoying Zhou
- Key Laboratory for Non-wood Forest Cultivation and Conservation of the Ministry of Education, Central South University of Forestry and Technology, Changsha, P.R. China
- College of Forestry, Central South University of Forestry and Technology, Changsha, P.R. China
| | - Junang Liu
- Key Laboratory for Non-wood Forest Cultivation and Conservation of the Ministry of Education, Central South University of Forestry and Technology, Changsha, P.R. China
- College of Forestry, Central South University of Forestry and Technology, Changsha, P.R. China
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da Silva SB, Cantarelli VV, Ayub MAZ. Production and optimization of poly-γ-glutamic acid by Bacillus subtilis BL53 isolated from the Amazonian environment. Bioprocess Biosyst Eng 2013; 37:469-79. [DOI: 10.1007/s00449-013-1016-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 07/08/2013] [Indexed: 12/01/2022]
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Zeng W, Lin Y, Qi Z, He Y, Wang D, Chen G, Liang Z. An integrated high-throughput strategy for rapid screening of poly(γ-glutamic acid)-producing bacteria. Appl Microbiol Biotechnol 2013; 97:2163-72. [PMID: 23361839 DOI: 10.1007/s00253-013-4717-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2013] [Accepted: 01/12/2013] [Indexed: 11/26/2022]
Abstract
Poly(γ-glutamic acid) (γ-PGA) is a promising biomaterial with a wide range of unique applications. To extensively screen γ-PGA-producing bacteria with high yield and different molecular weight, we developed an integrated high-throughput strategy. Firstly, γ-PGA-producing bacteria were selected in a primary screen plate containing a basic dye (neutral red) based on the concentric zone formed through the electrostatic interaction between the dye and the secreted acidic polymer γ-PGA. Then, the isolates were cultured in 50 ml tubes instead of 250 ml flasks. A good correlation of fermentation results in 50 ml tubes and 250 ml flasks was observed. Thirdly, the γ-PGA yield and weight-average molecular weight (M (w)) were simultaneously determined by spectrophotomic assay (UV assay) and neutral red plate assay. The results showed that the diameter of the concentric zone varied among isolates and was negatively correlated with the weight-average molecular weight of γ-PGA. The accuracy of the methods was comparable to that of high-performance liquid chromatography and gel permeation chromatography assay. Lastly, γ-PGA obtained from the target isolates was rapidly identified using thin layer chromatography assay. With this strategy, 13 bacteria with high yield and various molecular weights of γ-PGA from 500 obvious single colonies on the primary screen plate were obtained.
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Affiliation(s)
- Wei Zeng
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, 100 Daxue Road, Nanning 530004, Guangxi, China
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Effects of microbial elicitor on production of hypocrellin by Shiraia bambusicola. Folia Microbiol (Praha) 2012; 58:283-9. [PMID: 23229285 DOI: 10.1007/s12223-012-0203-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 10/19/2012] [Indexed: 10/27/2022]
Abstract
Some endophyte isolates were isolated in a bamboo pole sample parasitized the fungus Shiraia bambusicola from Zhejiang Province. After screening through hypocrellin bacteriostatic effect and fermentation test, we got the isolate TX4 of bacterial elicitor and GZUIFR-TT1 of fungal elicitor which had certain effect to promote S. bambusicola to produce hypocrellin. The Plackett-Burman design was introduced to evaluate the effects of nine factors based on single-factor test. Yeast extract, glucose, and isolate GZUIFR-TT1 elicitor were found to be the critical activity factors for increasing the total hypocrellin production. So we identified the isolate GZUIFR-TT1 as Trametes sp. Through response surface methodology, we obtained the optimum production conditions as follows: yeast extract, 2.99 g/L; glucose, 32.45 g/L; and Trametes sp. elicitor, 81.40 μg/mL. Under the above conditions, the experimental value of hypocrellin production was 102.60 mg/L, compared with the control it increased about 7.90 times.
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Kumdam HB, Murthy SN, Gummadi SN. A Statistical Approach to Optimize Xylitol Production by <i>Debaryomyces nepalensis</i> NCYC 3413 <i>in Vitro</i>. ACTA ACUST UNITED AC 2012. [DOI: 10.4236/fns.2012.38136] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Kannan N, Balamurugan SS. WITHDRAWN: Biosynthesis of silver nanoparticles: Parameter optimization using response surface method. Colloids Surf B Biointerfaces 2011:S0927-7765(11)00309-2. [PMID: 21683557 DOI: 10.1016/j.colsurfb.2011.05.034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Accepted: 05/18/2011] [Indexed: 11/27/2022]
Abstract
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
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Affiliation(s)
- N Kannan
- Department of Biotechnology, Manipal Institute of Technology, Manipal University,Manipal 576104,India
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Bajaj I, Singhal R. Poly (glutamic acid)--an emerging biopolymer of commercial interest. BIORESOURCE TECHNOLOGY 2011; 102:5551-61. [PMID: 21377358 DOI: 10.1016/j.biortech.2011.02.047] [Citation(s) in RCA: 214] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 02/09/2011] [Accepted: 02/10/2011] [Indexed: 05/08/2023]
Abstract
Poly (γ-glutamic acid) (PGA) is water-soluble, anionic, biodegradable, and edible biopolymer produced by Bacillus subtilis. It has multifarious potential applications in foods, pharmaceuticals, healthcare, water treatment and other fields. The production of PGA has already been established on the industrial scale. Various studies regarding the fermentative production, downstream processing and characterization of PGA have been reported in the literature. This review provides updated information on fermentative production of PGA by various bacterial strains and effect of fermentation conditions and media component on production of PGA in submerged as well as solid state fermentation. Information on the application of genetic engineering for enhancement of yield of PGA, kinetic studies for production of PGA in submerged fermentation and recovery and purification of PGA is included. An attempt has also been made to review the current and potential applications of PGA. This review may contribute to further development of this commercially and academically interesting biopolymer.
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Affiliation(s)
- Ishwar Bajaj
- Food Engineering and Technology Department, Institute of Chemical Technology, Matunga, Mumbai 400 019, India
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16
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Phytase production by Bacillus subtilis US417 in submerged and solid state fermentations. ANN MICROBIOL 2011. [DOI: 10.1007/s13213-011-0240-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Effect of aeration and agitation on synthesis of poly (γ-glutamic acid) in batch cultures of Bacillus licheniformis NCIM 2324. BIOTECHNOL BIOPROC E 2010. [DOI: 10.1007/s12257-009-0059-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Production of a new glycolipid biosurfactant from marine Nocardiopsis lucentensis MSA04 in solid-state cultivation. Colloids Surf B Biointerfaces 2010; 78:8-16. [DOI: 10.1016/j.colsurfb.2010.01.028] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 01/14/2010] [Accepted: 01/28/2010] [Indexed: 11/20/2022]
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19
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Optimization of the medium for streptolydigin production by Streptomyces lydicus AS 4.2501 with precursor feeding using response surface methodology. J Taiwan Inst Chem Eng 2010. [DOI: 10.1016/j.jtice.2009.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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20
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Zhu BF, Xu Y, Fan WL. High-yield fermentative preparation of tetramethylpyrazine by Bacillus sp. using an endogenous precursor approach. J Ind Microbiol Biotechnol 2009; 37:179-86. [DOI: 10.1007/s10295-009-0661-5] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2009] [Accepted: 10/23/2009] [Indexed: 11/30/2022]
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21
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Nasri Nasrabadi MR, Razavi SH. Use of response surface methodology in a fed-batch process for optimization of tricarboxylic acid cycle intermediates to achieve high levels of canthaxanthin from Dietzia natronolimnaea HS-1. J Biosci Bioeng 2009; 109:361-8. [PMID: 20226378 DOI: 10.1016/j.jbiosc.2009.10.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2009] [Revised: 10/08/2009] [Accepted: 10/15/2009] [Indexed: 11/30/2022]
Abstract
In this work, we applied statistical experimental design to a fed-batch process for optimization of tricarboxylic acid cycle (TCA) intermediates in order to achieve high-level production of canthaxanthin from Dietzia natronolimnaea HS-1 cultured in beet molasses. A fractional factorial design (screening test) was first conducted on five TCA cycle intermediates. Out of the five TCA cycle intermediates investigated via screening tests, alfaketoglutarate, oxaloacetate and succinate were selected based on their statistically significant (P<0.05) and positive effects on canthaxanthin production. These significant factors were optimized by means of response surface methodology (RSM) in order to achieve high-level production of canthaxanthin. The experimental results of the RSM were fitted with a second-order polynomial equation by means of a multiple regression technique to identify the relationship between canthaxanthin production and the three TCA cycle intermediates. By means of this statistical design under a fed-batch process, the optimum conditions required to achieve the highest level of canthaxanthin (13172 + or - 25 microg l(-1)) were determined as follows: alfaketoglutarate, 9.69 mM; oxaloacetate, 8.68 mM; succinate, 8.51 mM.
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Affiliation(s)
- Mohammad Reza Nasri Nasrabadi
- Department of Food Science and Engineering, Faculty of Biosystem Engineering, College of Agriculture, University of Tehran, P.O. Box 31587-78659, Karaj, Islamic Republic of Iran
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22
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Statistical optimization of α-amylase production by Bacillus brevis MTCC 7521 in solid-state fermentation using cassava bagasse. Biologia (Bratisl) 2009. [DOI: 10.2478/s11756-009-0160-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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23
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Swain MR, Kar S, Ray RC. Exo-polygalacturonase production by Bacillus subtilis CM5 in solid state fermentation using cassava bagasse. Braz J Microbiol 2009; 40:636-48. [PMID: 24031409 PMCID: PMC3768540 DOI: 10.1590/s1517-838220090003000028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Revised: 02/10/2009] [Accepted: 05/03/2009] [Indexed: 11/21/2022] Open
Abstract
The purpose of this investigation was to study the effect of Bacillus subtilis CM5 in solid state fermentation using cassava bagasse for production of exo-polygalacturonase (exo-PG). Response surface methodology was used to evaluate the effect of four main variables, i.e. incubation period, initial medium pH, moisture holding capacity (MHC) and incubation temperature on enzyme production. A full factorial Central Composite Design was applied to study these main factors that affected exo-PG production. The experimental results showed that the optimum incubation period, pH, MHC and temperature were 6 days, 7.0, 70% and 50°C, respectively for optimum exo-PG production.
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Affiliation(s)
- Manas R Swain
- Central Tuber Crops Research Institute (Regional Centre) , Bhubaneswar - 751019 , India
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24
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Bajaj IB, Singhal RS. Flocculation Properties of Poly(γ-Glutamic Acid) Produced from Bacillus subtilis Isolate. FOOD BIOPROCESS TECH 2009. [DOI: 10.1007/s11947-009-0186-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Bajaj IB, Lele SS, Singhal RS. A statistical approach to optimization of fermentative production of poly(gamma-glutamic acid) from Bacillus licheniformis NCIM 2324. BIORESOURCE TECHNOLOGY 2009; 100:826-32. [PMID: 18676141 DOI: 10.1016/j.biortech.2008.06.047] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2008] [Revised: 06/21/2008] [Accepted: 06/24/2008] [Indexed: 05/08/2023]
Abstract
This paper reports on the optimization of poly(gamma-glutamic acid) (PGA) production by Bacillus licheniformis NCIM 2324 using a statistical approach. One-factor-at-a-time method was used to investigate the effect of carbon sources, nitrogen sources and pH on PGA production. Plackett-Burman design was adopted to select the most important nutrients influencing the yield of PGA. After identifying effective nutrients, response surface methodology was used to develop a mathematical model to identify the optimum concentrations of the key nutrients for higher PGA production, and confirm its validity experimentally. PGA production increased significantly from 5.27 to 26.12 g/l when the strain was cultivated in the optimal medium developed by using statistical approach, as compared to basal medium.
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Affiliation(s)
- I B Bajaj
- Food Engineering and Technology Department, Institute of Chemical Technology, University of Mumbai, Nathlal Parikh Marg, Matunga, Mumbai 400 019, India.
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26
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Bajaj IB, Singhal RS. Enhanced Production of Poly (γ-glutamic acid) from Bacillus licheniformis NCIM 2324 by Using Metabolic Precursors. Appl Biochem Biotechnol 2008; 159:133-41. [DOI: 10.1007/s12010-008-8427-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2008] [Accepted: 10/30/2008] [Indexed: 11/24/2022]
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27
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Buescher JM, Margaritis A. Microbial Biosynthesis of Polyglutamic Acid Biopolymer and Applications in the Biopharmaceutical, Biomedical and Food Industries. Crit Rev Biotechnol 2008; 27:1-19. [PMID: 17364686 DOI: 10.1080/07388550601166458] [Citation(s) in RCA: 168] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This review article provides an updated critical literature review on the production and applications of Polyglutamic Acid (PGA). alpha-PGA is synthesized chemically, whereas gamma-PGA can be produced by a number of microbial species, most prominently various Bacilli. Great insight into the microbial formation of gamma-PGA has been gained thanks to the development of molecular biological techniques. Moreover, there is a great variety of applications for both isoforms of PGA, many of which have not been discovered until recently. These applications include: wastewater treatment, food products, drug delivery, medical adhesives, vaccines, PGA nanoparticles for on-site drug release in cancer chemotherapy, and tissue engineering.
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Affiliation(s)
- Joerg M Buescher
- Institute of Molecular Systems Biology, ETH Zurich, Zurich, Switzerland
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28
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Enhanced production of poly (γ-glutamic acid) from Bacillus licheniformis NCIM 2324 in solid state fermentation. J Ind Microbiol Biotechnol 2008; 35:1581-6. [DOI: 10.1007/s10295-008-0401-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Accepted: 07/09/2008] [Indexed: 11/26/2022]
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29
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Jia B, Jin ZH, Mei LH. Medium optimization based on statistical methodologies for pristinamycins production by Streptomyces pristinaespiralis. Appl Biochem Biotechnol 2008; 144:133-43. [PMID: 18456945 DOI: 10.1007/s12010-007-8012-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The optimization of nutrient levels for the production of pristinamycins by Streptomyces pristinaespiralis CGMCC 0957 in submerged fermentation was carried out using the statistical methodologies based on the Plackett-Burman design, the steepest ascent method, and the central composite design (CCD). First, the Plackett-Burman design was applied to evaluate the influence of related nutrients in the medium. Soluble starch and MgSO4 x 7H2O were then identified as the most significant nutrients with a confidence level of 99%. Subsequently, the concentrations of the two nutrients were further optimized using response surface methodology of CCD, together with the steepest ascent method. Accordingly, a second-order polynomial regression model was finally fitted to the experimental data. By solving the regression equation from the model and analyzing the response surface, the optimal levels for soluble starch and MgSO4 x 7H2O were determined as 20.95 and 5.67g/L, respectively. Under the optimized medium, the yield of pristinamycins in the shake flask and 5-L bioreactor could reach 1.30 and 1.01 g/L, respectively, which is the highest yield reported in literature to date.
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Affiliation(s)
- B Jia
- Department of Biological and Pharmaceutical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, People's Republic of China
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30
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Kar S, Swain MR, Ray RC. Statistical optimization of alpha-amylase production with immobilized cells of Streptomyces erumpens MTCC 7317 in Luffa cylindrica L. sponge discs. Appl Biochem Biotechnol 2008; 152:177-88. [PMID: 18521760 DOI: 10.1007/s12010-008-8248-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2007] [Accepted: 04/09/2008] [Indexed: 11/26/2022]
Abstract
The purpose of this investigation was to study the effect of Streptomyces erumpens cells immobilized in various matrices, i.e., agar-agar, polyacrylamide, and luffa (Luffa cylindrica L.) sponge for production of alpha-amylase. Luffa sponge was found to be 21% and 51% more effective in enzyme yield than agar-agar and polyacrylamide, respectively. Response surface methodology was used to evaluate the effect of three main variables, i.e., incubation period, pH, and temperature on enzyme production with immobilized luffa cells. The experimental results showed that the optimum incubation period, pH, and temperature were 36h, 6.0, and 50 degrees C, respectively. The repeated batch fermentation of immobilized cells in shake flasks showed that S. erumpens cells were more or less equally physiologically active on the support even after three cycles of fermentation (3,830-3,575 units). The application of S. erumpens crude enzyme in liquefying cassava starch was studied. The maximum hydrolysis of cassava starch (85%) was obtained with the application of 4ml (15,200 units) of crude enzyme after 5 h of incubation.
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Affiliation(s)
- Shaktimay Kar
- Microbiology Laboratory, Regional Center of Central Tuber crops Research Institute, Bhubaneswar, India
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31
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Dash SS, Gummadi SN. Enhanced biodegradation of caffeine by Pseudomonas sp. using response surface methodology. Biochem Eng J 2007. [DOI: 10.1016/j.bej.2007.03.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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32
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Swain MR, Ray RC. Alpha-amylase production byBacillus subtilis CM3 in solid state fermentation using cassava fibrous residue. J Basic Microbiol 2007; 47:417-25. [PMID: 17910107 DOI: 10.1002/jobm.200710132] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In extraction of starch from cassava (Manihot esculenta Crantz), one of the major solid waste released is fibrous residues which constitute 15-20% by weight of the cassava chips/tuber processed. Production of alpha -amylase under solid state fermentation by Bacillus subtilis CM3 has been investigated using cassava fibrous residue. Response surface methodology (RSM) was used to evaluate the effect of the main variables, i.e. incubation period, initial medium pH, moisture holding capacity and temperature on enzyme production. A full factorial Central Composite Design (CCD) was applied to study these main factors that affected alpha -amylase production. The experimental results showed that the optimum incubation period, initial medium pH, moisture holding capacity and temperature were 6 days, 8.0, 70% and 50 degrees C, respectively.
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Affiliation(s)
- M R Swain
- Central Tuber Crops Research Institute Regional Centre, Dumuduma Housing Board, Bhubaneswar, India
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Preetha R, Jayaprakash NS, Philip R, Bright Singh IS. Optimization of medium for the production of a novel aquaculture probiotic,Micrococcus MCCB 104 using central composite design. BIOTECHNOL BIOPROC E 2007. [DOI: 10.1007/bf02931353] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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34
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Mizumoto S, Shoda M. Medium optimization of antifungal lipopeptide, iturin A, production by Bacillus subtilis in solid-state fermentation by response surface methodology. Appl Microbiol Biotechnol 2007; 76:101-8. [PMID: 17476498 DOI: 10.1007/s00253-007-0994-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Revised: 04/05/2007] [Accepted: 04/10/2007] [Indexed: 12/01/2022]
Abstract
Iturin A, a lipopeptide antibiotic produced by Bacillus subtilis RB14-CS, suppresses the growth of various plant pathogens. Here, enhancement of iturin A production in solid-state fermentation (SSF) on okara, a soybean curd residue produced during tofu manufacturing, was accomplished using statistical experimental design. Primary experiments showed that the concentrations of carbon and nitrogen sources were the main factors capable of enhancing iturin A production, whereas initial pH, initial water content, temperature, relative humidity, and volume of inoculum were only minor factors. Glucose and soybean meal were the most effective among tested carbon and nitrogen sources, respectively. Based on these preliminary findings, response surface methodology was applied to predict the optimum amounts of the carbon and nitrogen sources in the medium. The maximum iturin A concentration was 5,591 mug/g initial wet okara under optimized condition. Subsequent experiments confirmed that iturin A production was significantly improved under the predicted optimal medium conditions. The SSF product generated under the optimized conditions exhibited significantly higher suppressive effect on the damping-off of tomato caused by Rhizoctonia solani K-1 compared with the product generated under the non-optimized conditions.
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Affiliation(s)
- Shinji Mizumoto
- Chemical Resources Laboratory, Tokyo Institute of Technology, R1-29, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan
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Xiao ZJ, Liu PH, Qin JY, Xu P. Statistical optimization of medium components for enhanced acetoin production from molasses and soybean meal hydrolysate. Appl Microbiol Biotechnol 2007; 74:61-8. [PMID: 17043817 DOI: 10.1007/s00253-006-0646-5] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2006] [Revised: 08/18/2006] [Accepted: 08/22/2006] [Indexed: 11/27/2022]
Abstract
The nutritional requirements for acetoin production by Bacillus subtilis CICC 10025 were optimized statistically in shake flask experiments using indigenous agroindustrial by-products. The medium components considered for initial screening in a Plackett-Burman design comprised a-molasses (molasses submitted to acidification pretreatment), soybean meal hydrolysate (SMH), KH(2)PO(4).3H(2)O, sodium acetate, MgSO(4).7H(2)O, FeCl(2), and MnCl(2), in which the first two were identified as significantly (at the 99% significant level) influencing acetoin production. Response surface methodology was applied to determine the mutual interactions between these two components and optimal levels for acetoin production. In flask fermentations, 37.9 g l(-1) acetoin was repeatedly achieved using the optimized concentrations of a-molasses and SMH [22.0% (v/v) and 27.8% (v/v), respectively]. a-Molasses and SMH were demonstrated to be more productive than pure sucrose and yeast extract plus peptone, respectively, in acetoin fermentation. In a 5-l fermenter, 35.4 g l(-1) of acetoin could be obtained after 56.4 h of cultivation. To our knowledge, these results, i.e., acetoin yields in flask or fermenter fermentations, were new records on acetoin fermentation by B. subtilis.
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Affiliation(s)
- Z J Xiao
- State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, People's Republic of China
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