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Govindaraj V, Kim SK, Raval R, Raval K. Marine Bacillus haynesii chitinase: Purification, characterization and antifungal potential for sustainable chitin bioconversion. Carbohydr Res 2024; 541:109170. [PMID: 38830279 DOI: 10.1016/j.carres.2024.109170] [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: 03/21/2024] [Revised: 05/07/2024] [Accepted: 05/29/2024] [Indexed: 06/05/2024]
Abstract
The development of chitinase tailored for the bioconversion of chitin to chitin oligosaccharides has attracted significant attention due to its potential to alleviate environmental pollution associated with chemical conversion processes. In this present investigation, we purified extracellular chitinase derived from marine Bacillus haynesii to homogeneity and subsequently characterized it. The molecular weight of BhChi was approximately 35 kDa. BhChi displayed its peak catalytic activity at pH 6.0, with an optimal temperature of 37 °C. It exhibited stability across a pH range of 6.0-9.0. In addition, BhChi showed activation in the presence of Mn2+ with the improved activity of 105 U mL-1. Ca2+ and Fe2+ metal ions did not have any significant impact on enzyme activity. Under the optimized enzymatic conditions, there was a notable enhancement in catalytic activity on colloidal chitin with Km of 0.01 mg mL-1 and Vmax of 5.75 mmol min-1. Kcat and catalytic efficiency were measured at 1.91 s-1 and 191 mL mg-1 s-1, respectively. The product profiling of BhChi using thin layer chromatography and Mass spectrometric techniques hinted an exochitinase mode of action with chitobiose and N-Acetyl glucosamine as the products. This study represents the first report on an exochitinase from Bacillus haynesii. Furthermore, the chitinase showcased promising antifungal properties against key pathogens, Fusarium oxysporum and Penicillium chrysogenum, reinforcing its potential as a potent biocontrol agent.
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Affiliation(s)
- Vishnupriya Govindaraj
- Department of Chemical Engineering, National Institute of Technology, Surathkal, Mangalore, 575025, Karnataka, India
| | - Se-Kwon Kim
- Department of Marine Science & Convergence Engineering, College of Science & Technology, Hanyang, University Erica Campus, Ansan, 11558, Republic of Korea.
| | - Ritu Raval
- Department of Biotechnology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India.
| | - Keyur Raval
- Department of Chemical Engineering, National Institute of Technology, Surathkal, Mangalore, 575025, Karnataka, India.
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Divya K, Thampi M, Vijayan S, Shabanamol S, Jisha MS. Chitosan nanoparticles as a rice growth promoter: evaluation of biological activity. Arch Microbiol 2021; 204:95. [DOI: 10.1007/s00203-021-02669-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 10/15/2021] [Accepted: 10/17/2021] [Indexed: 11/29/2022]
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Thakur N, Nath AK, Chauhan A, Gupta R. Purification, characterization, and antifungal activity of Bacillus cereus strain NK91 chitinase from rhizospheric soil samples of Himachal Pradesh, India. Biotechnol Appl Biochem 2021; 69:1830-1842. [PMID: 34486170 DOI: 10.1002/bab.2250] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/30/2021] [Indexed: 12/27/2022]
Abstract
Newly isolated Bacillus cereus strain NK91 was characterized for extracellular chitinase production. Partially purified chitinase showed a molecular weight of 43.7 kDa in SDS-PAGE analysis. The optimum pH and temperature for the partially purified enzyme were 7.0 and 40°C, respectively. The addition of Mn2+ resulted in a 21% increase in enzyme activity as compared to the control. The Vmax and Km of the enzyme were determined as 76.9 μmol/min and 0.07 mg/mL, respectively. This enzyme exhibited stronger antifungal activity towards Fusarium oxysporum (66.7%), Rhizoctonia solani (64.6%), and Colletotrichum gloeosporioides (63%), and transmission electron microscopy and scanning transmission electron microscopy analysis showed considerable changes in cell wall structure with the treatment of purified chitinase as compared to control. Therefore, this enzyme reveals its biocontrol potential against potent phytopathogens in agriculture that can be helpful in swapping harmful as well as expensive fungicides.
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Affiliation(s)
- Nirja Thakur
- Department of Biotechnology, College of Horticulture, Dr. Y. S. Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, 173 230, India
| | - Amarjit K Nath
- Department of Biotechnology, College of Horticulture, Dr. Y. S. Parmar University of Horticulture and Forestry, Nauni, Solan, Himachal Pradesh, 173 230, India
| | - Anjali Chauhan
- Department of Soil Science and Water Management, College of Forestry, Dr Y r University of Horticulture and Forestry, Nauni, Solan, 173 230, India
| | - Rakesh Gupta
- Directorate of Research, Dr. Y. S. Parmar University of Horticulture and Forestry, Nauni, Solan, 173 230, India
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Singh RV, Sambyal K, Negi A, Sonwani S, Mahajan R. Chitinases production: A robust enzyme and its industrial applications. BIOCATAL BIOTRANSFOR 2021. [DOI: 10.1080/10242422.2021.1883004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
| | - Krishika Sambyal
- University Institute of Biotechnology, Chandigarh University, Gharuan, India
| | - Anjali Negi
- University Institute of Biotechnology, Chandigarh University, Gharuan, India
| | - Shubham Sonwani
- Department of Biosciences, Christian Eminent College, Indore, India
| | - Ritika Mahajan
- Department of Microbiology, School of Sciences, JAIN (Deemed-to-be University), Bengaluru, India
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Suganthi M, Arvinth S, Senthilkumar P. Comparative bioefficacy of Bacillus and Pseudomonas chitinase against Helopeltis theivora in tea ( Camellia sinensis (L.) O.Kuntze. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2020; 26:2053-2060. [PMID: 33088049 PMCID: PMC7548272 DOI: 10.1007/s12298-020-00875-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 08/14/2020] [Accepted: 08/26/2020] [Indexed: 06/11/2023]
Abstract
Tea (Camellia sinensis (L.) O.Kuntze) is an industry-oriented economical crop in India. Among the sap sucking pests, tea mosquito bug (Helopeltis theivora) is one of the most serious pests causing heavy crop loss in tea plantation. Continuous use of chemical pesticides causes environmental pollution and health hazards besides developing pesticide residues in tea powder. The control of pests by bacterial metabolite is an alternative that may contribute to reduce or eliminate the chemical pesticide use. The use of chitinase as a biological control is an emerging field of research. In the present study, Chitinase (~ 25 kDa) was purified from Bacillus cereus C-13 strain using gel-filtration chromatography and further characterized for its optimum pH, temperature and substrate specificity. Bioefficacy of chitinase from B. cereus C-13 was compared with our previously reported Pseudomonas fluorescens MP-13 chitinase against H. theivora. Result concluded that, 100% and 78% mortality was observed by using P. fluorescens MP-13 chitinase and B. cereus C-13 chitinase, respectively. In future, bacterial chitinase can be utilized in eco-friendly pest management strategies.
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Affiliation(s)
- M. Suganthi
- Department of Plant Physiology and Biotechnology, UPASI Tea Research Institute, Valparai, Tamilnadu 642 127 India
- Department of Biotechnology, Vels Institute of Science, Technology and Advanced Studies (VISTAS), Pallavaram, Chennai, Tamilnadu 600 117 India
| | - S. Arvinth
- Department of Plant Physiology and Biotechnology, UPASI Tea Research Institute, Valparai, Tamilnadu 642 127 India
- Department of Botany, PSG College of Arts and Science, Coimbatore, Tamilnadu 641 004 India
| | - P. Senthilkumar
- Department of Genetic Engineering, School of Bioengineering, SRM Institute of Science and Technology, Potheri, Kattankulathur, Chengalpattu District, Tamilnadu 603 203 India
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Subramanian K, Sadaiappan B, Aruni W, Kumarappan A, Thirunavukarasu R, Srinivasan GP, Bharathi S, Nainangu P, Renuga PS, Elamaran A, Balaraman D, Subramanian M. Bioconversion of chitin and concomitant production of chitinase and N-acetylglucosamine by novel Achromobacter xylosoxidans isolated from shrimp waste disposal area. Sci Rep 2020; 10:11898. [PMID: 32681120 PMCID: PMC7368032 DOI: 10.1038/s41598-020-68772-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 06/22/2020] [Indexed: 11/09/2022] Open
Abstract
Marine pollution is a significant issue in recent decades, with the increase in industries and their waste harming the environment and ecosystems. Notably, the rise in shellfish industries contributes to tons of shellfish waste composed of up to 58% chitin. Chitin, the second most ample polymer next to cellulose, is insoluble and resistant to degradation. It requires chemical-based treatment or enzymatic hydrolysis to cleave the chitin polymers. The chemical-based treatment can lead to environmental pollution, so to solve this problem, enzymatic hydrolysis is the best option. Moreover, the resulting biopolymer by-products can be used to boost the fish immune system and also as drug delivery agents. Many marine microbial strains have chitinase producing ability. Nevertheless, we still lack an economical and highly stable chitinase enzyme for use in the industrial sector. So we isolate a novel marine bacterial strain Achromobacter xylosoxidans from the shrimp waste disposal site using chitin minimal medium. Placket-Burman and central composite design statistical models for culture condition optimisation predicted a 464.2 U/ml of chitinase production. The culture conditions were optimised for maximum chitinase production recording up to 467 U/ml. This chitinase from the A. xylosoxidans was 100% active at an optimum temperature of 45 °C (withstand up to 55 °C) and pH 8 with 80% stability. The HPLC analysis of chitinase degraded shellfish waste reveals a major amino acid profile composition-arginine, lysine, aspartic acid, alanine, threonine and low levels of isoleucine and methionine. These chitinase degraded products and by-products can be used as supplements in the aquaculture industry.
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Affiliation(s)
- Kumaran Subramanian
- School of Bio and Chemical Engineering, Sathyabama Institute of Science and Technology, Chennai, Tamil Nadu, 600119, India.,Centre for Drug Discovery and Development, Sathyabama Institute of Science and Technology, Chennai, Tamil Nadu, 600119, India
| | - Balamurugan Sadaiappan
- Plankton Ecology Laboratory, CSIR- National Institute of Oceanography, Panaji, Goa, 403004, India
| | - Wilson Aruni
- School of Bio and Chemical Engineering, Sathyabama Institute of Science and Technology, Chennai, Tamil Nadu, 600119, India.,School of Medicine, Loma Linda University, Loma Linda, CA, 92350, USA
| | | | - Rajasekar Thirunavukarasu
- Centre for Drug Discovery and Development, Sathyabama Institute of Science and Technology, Chennai, Tamil Nadu, 600119, India
| | - Guru Prasad Srinivasan
- Centre for Advanced Studies in Marine Biology, Annamalai University, Chidambaram, Tamil Nadu, 608502, India
| | - Selvaraj Bharathi
- Department of Microbiology, Sri Sankara Arts and Science College, Enathur, Tamil Nadu, 631561, India
| | - Prasannabalaji Nainangu
- Department of Microbiology, Sri Sankara Arts and Science College, Enathur, Tamil Nadu, 631561, India
| | | | - Anandajothi Elamaran
- Centre for Advanced Studies in Marine Biology, Annamalai University, Chidambaram, Tamil Nadu, 608502, India.,Central Aquaculture Genetics Laboratory, Rajiv Gandhi Centre for Aquaculture, Karaimedu, Tamil Nadu, 609109, India
| | - Deivasigamani Balaraman
- Centre for Advanced Studies in Marine Biology, Annamalai University, Chidambaram, Tamil Nadu, 608502, India
| | - Mahendran Subramanian
- Department of Bioengineering, Department of Computing, Imperial College London, London, SW72AZ, UK.
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Darwesh OM, El-Hawary AS, El Kelany US, El-Sherbiny GM. Nematicidal activity of thermostable alkaline protease produced by Saccharomonospora viridis strain Hw G550. ACTA ACUST UNITED AC 2019; 24:e00386. [PMID: 31763199 PMCID: PMC6864322 DOI: 10.1016/j.btre.2019.e00386] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/07/2019] [Accepted: 10/10/2019] [Indexed: 11/23/2022]
Abstract
Isolation and identification of thermo alkaliphilic actinomycetes. Obtaining of thermostable alkaline protease enzyme. Evaluation of the nematicidal activity of obtained protease. Application of thermostable alkaline protease as nemticidal agent.
Application of thermostable alkaline protease to control the harmful nematodes was investigated in the current study. A total of 14 proteolytic actinomycetes were isolated from Egyptian harsh environments. Out of them, isolate G550 exhibited the highest proteolytic activity (528.9 U/ml). Protease from isolate G550 exhibited high nematicidal activity against M. incognita under laboratory conditions and caused hydrolysis of J2S cuticle. This isolate was identified using molecular techniques and deposited in GenBank under name of Saccharomonospora viridis strain Hw G550 with accession number: MF152631. The G550 protease was extracted, characterized and applied under greenhouse conditions as nematicidal agent. This enzyme exhibited maximum activity and stability at alkaline pH (8) and thermal conditions (50–60 °C). Also, the results showed that, all treatments using protease caused a significant decrease in nematode reproduction and increasing in the plant properties. Finally, the thermo alkaliphilic protease could be used as bio-control agent against RKN.
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Affiliation(s)
- Osama M Darwesh
- Agricultural Microbiology Department, National Research Centre, Dokki, Cairo, Egypt
| | - Ahmad S El-Hawary
- Botany and Microbiology Department, Faculty of Science (Boys), Al-Azhar University, Nasr city, Cairo, Egypt
| | - Usama S El Kelany
- Plant Pathology Department, Agricultural and Biological Division, National Research Centre, Cairo, Egypt
| | - Gamal M El-Sherbiny
- Botany and Microbiology Department, Faculty of Science (Boys), Al-Azhar University, Nasr city, Cairo, Egypt
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Singh G, Arya SK. Antifungal and insecticidal potential of chitinases: A credible choice for the eco-friendly farming. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.101289] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Comparative biocontrol ability of chitinases from bacteria and recombinant chitinases from the thermophilic fungus Thermomyces lanuginosus. J Biosci Bioeng 2019; 127:663-671. [PMID: 30670323 DOI: 10.1016/j.jbiosc.2018.11.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 11/08/2018] [Accepted: 11/14/2018] [Indexed: 01/05/2023]
Abstract
Microbial chitinases (EC 3.2.1.14) are known to hydrolyse the chitinous gut epithelium of insects and cell walls of many fungi. In this study, seven chitinases from different bacteria and fungi were produced, characterized and their biocontrol abilities against graminaceous stem borers Eldana saccharina, Chilo partellus and Sesamia calamistis were assessed. All chitinases were stable over broad ranges of pH and temperature, however, recombinant fungal chitinases were more acid-stable than the bacterial counterparts. Chitinases from the thermophilic filamentous fungi Thermomyces lanuginosus SSBP (Chit1) and from Bacillus licheniformis (Chit lic) caused 70% and 80% mortality, respectively, in second instar larvae of E. saccharina. Six of the seven partially-purified microbial chitinases inhibited Aspergillus niger, A. flavus, A. alliaceus, A. ochraceus, Fusarium verticillioides and Mucor sp. Overall, microbial chitinases show promise as biocontrol agents of fungi and stalk-boring lepidopterans.
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dos Reis CBL, Sobucki L, Mazutti MA, Guedes JVC, Jacques RJS. Production of Chitinase fromMetarhizium anisopliaeby Solid-State Fermentation Using Sugarcane Bagasse as Substrate. Ind Biotechnol (New Rochelle N Y) 2018. [DOI: 10.1089/ind.2017.0031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | - Lisiane Sobucki
- Department of Soil Science, Federal University of Santa Maria, Santa Maria, Brazil
| | - Marcio Antonio Mazutti
- Department of Chemical Engineering, Federal University of Santa Maria, Santa Maria, Brazil
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Kadier A, Abdeshahian P, Kalil MS, Hasan HA, Hamid AA. Optimization of the Key Medium Components and Culture Conditions for Efficient Cultivation of G. sulfurreducens Strain PCA ATCC 51573 Using Response Surface Methodology. IRANIAN JOURNAL OF SCIENCE AND TECHNOLOGY TRANSACTION A-SCIENCE 2018. [DOI: 10.1007/s40995-018-0501-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Rishad KS, Rebello S, Shabanamol PS, Jisha MS. Biocontrol potential of Halotolerant bacterial chitinase from high yielding novel Bacillus Pumilus MCB-7 autochthonous to mangrove ecosystem. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2017; 137:36-41. [PMID: 28364802 DOI: 10.1016/j.pestbp.2016.09.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Revised: 09/19/2016] [Accepted: 09/23/2016] [Indexed: 06/07/2023]
Abstract
The multifaceted role of chitinase in medicine, agriculture, environmental remediation and various other industries greatly demands the isolation of high yielding chitinase producing microorganisms with improved properties. The current study aimed to investigate the isolation, characterization and biocontrol prospective of chitinase producing bacterial strains autochthonous to the extreme conditions of mangrove ecosystems. Among the 51 bacterial isolates screened, Bacillus pumilus MCB-7 with highest chitinase production potential was identified and confirmed by 16S rDNA typing. Chitinase enzyme of MCB-7 was purified; the chitin degradation was evaluated by SEM and LC-MS. Unlike previously reported B.pumilus isolates, MCB-7 exhibited highest chitinase activity of 3.36U/mL, active even at high salt concentrations and temperature up to 60°C. The crude as well as purified enzyme showed significant antimycotic activity against agricultural pathogens such as Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, Ceratorhiza hydrophila and Fusarium oxysporum. The enzyme also exhibited biopesticidal role against larvae of Scirpophaga incertulas (Walker). [Lep.: Pyralidae], a serious agricultural pest of rice. The high chitinolytic and antimycotic potential of MCB-7 increases the prospects of the isolate as an excellent biocontrol agent. To the best of our knowledge, this is the first report of high chitinase yielding Bacillus pumilus strain from mangrove ecosystem with a biocontrol role against phytopathogenic fungi and insect larval pests.
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Affiliation(s)
- K S Rishad
- School of Biosciences, Mahatma Gandhi University, Kottayam, Kerala, India
| | | | - P S Shabanamol
- School of Biosciences, Mahatma Gandhi University, Kottayam, Kerala, India
| | - M S Jisha
- School of Biosciences, Mahatma Gandhi University, Kottayam, Kerala, India.
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Molecular advancements in the development of thermostable phytases. Appl Microbiol Biotechnol 2017; 101:2677-2689. [PMID: 28233043 DOI: 10.1007/s00253-017-8195-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Revised: 02/12/2017] [Accepted: 02/13/2017] [Indexed: 12/20/2022]
Abstract
Since the discovery of phytic acid in 1903 and phytase in 1907, extensive research has been carried out in the field of phytases, the phytic acid degradatory enzymes. Apart from forming backbone enzyme in the multimillion dollar-based feed industry, phytases extend a multifaceted role in animal nutrition, industries, human physiology, and agriculture. The utilization of phytases in industries is not effectively achieved most often due to the loss of its activity at high temperatures. The growing demand of thermostable phytases with high residual activity could be addressed by the combinatorial use of efficient phytase sources, protein engineering techniques, heterologous expression hosts, or thermoprotective coatings. The progress in phytase research can contribute to its economized production with a simultaneous reduction of various environmental problems such as eutrophication, greenhouse gas emission, and global warming. In the current review, we address the recent advances in the field of various natural as well as recombinant thermotolerant phytases, their significance, and the factors contributing to their thermotolerance.
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Viswanath V, Leo VV, Prabha SS, Potty VP, Jisha MS. Optimized Production of Tannase from Cashew Testa usingAspergillus nigerMTCC 5898. FOOD BIOTECHNOL 2016. [DOI: 10.1080/08905436.2016.1234392] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Enhancement of Exochitinase Production by Bacillus licheniformis AT6 Strain and Improvement of N-Acetylglucosamine Production. Appl Biochem Biotechnol 2016; 181:650-666. [PMID: 27639392 DOI: 10.1007/s12010-016-2239-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 09/05/2016] [Indexed: 10/21/2022]
Abstract
A strain producing chitinase, isolated from potato stem tissue, was identified as Bacillus licheniformis by biochemical properties and 16S RNA sequence analysis. Statistical experimental designs were used to optimize nine independent variables for chitinase production by B. licheniformis AT6 strain in submerged fermentation. Using Plackett-Burman design, (NH4)2SO4, MgSO4.7H2O, colloidal chitin, MnCl2 2H2O, and temperature were found to influence chitinase production significantly. According to Box-Behnken response surface methodology, the optimal fermentation conditions allowing maximum chitinase production were (in gram per liter): (NH4)2SO4, 7; K2HPO4, 1; NaCl, 1; MgSO4.7H2O, 0.1; yeast extract, 0.5; colloidal chitin, 7.5; MnCl2.2H2O, 0.2; temperature 35 °C; pH medium 7. The optimization strategy led to a 10-fold increase in chitinase activity (505.26 ± 22.223 mU/mL versus 50.35 ± 19.62 mU/mL for control basal medium). A major protein band with a molecular weight of 61.9 kDa corresponding to chitinase activity was clearly detected under optimized conditions. Chitinase activity produced in optimized medium mainly releases N-acetyl glucosamine (GlcNAc) monomer from colloidal chitin. This enzyme also acts as an exochitinase with β-N-acetylglucosaminidase. These results suggest that B. licheniformis AT6 secreting exochitinase is highly efficient in GlcNAc production which could in turn be envisaged as a therapeutic agent or as a conservator against the alteration of several ailments.
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