Please use this identifier to cite or link to this item:
Title: Production, purification and characterization of ß-glucosidase from Paecilomyces variotii
Researcher: Job, Joseph
Guide(s): Jaychandran, K
Keywords: Glucose resistant
Paecilomyces variotii
Plackett-Burman Design
Box- Behnken Design
Solid state fermentation
Upload Date: 22-Nov-2013
University: Mahatma Gandhi University
Completed Date: 2010
Abstract: A fungal strain Paecilomyces variotii MG3 capable of producing and#946;-glucosidase was selected from twelve isolates screened for the production of and#946;-glucosidase. The various process parameters influencing the production of the enzyme through submerged fermentation as well as solid state fermentation were optimized. Optimization of parameters for solid state fermentation was carried out by a two step statistical design of experiment approach. The influencing parameters were identified using Plackett-Burman Design and the identified factors were further optimized using Box-Behnken Design. The modeling was done using the DesignExpert software. The optimum levels of the most influencing parameters obtained were peptone concentration of 2g/L, inoculums concentration of 1.2 X 106 spores /ml and incubation period of 96h. Purification of the enzyme using ammonium sulphate fractionation, gel filtration and anion exchange chromatography established the presence of two isozymes. Isozymes I and II were monomeric proteins with molecular weights of approximately 40kDa and 90kDa respectively. The optimum pH of isozyme I was 6 and that of isozyme II was 5 with broad pH stability range of 3 to 7. Vmax and Km were determined using non linear regression curve fitting function of the GraphpadPrism software. Vmax values of isozyme I and II were 0.2497U/ml and 0.3519 U/ml respectively with pNPG as substrate. The Km value of isozyme I was 0.08839mM and that of the other isozyme was 0.2710 mM. Isozyme II was highly sensitive to glucose concentrations higher than 0.5M and isozyme I was resistant to glucose concentrations as high as 2M. The Ki values of isozyme I and II were found to be 901.6 mM and 22.65 mM respectively. The glucose resistant isozyme I was found to be capable of acting on cellulose in combination with cellulase and the crude enzyme was found to enhance the release of vanillin from vanilla beans.
Pagination: 191p.
Appears in Departments:School of Bio Sciences

Files in This Item:
File Description SizeFormat 
01_title.pdfAttached File102.67 kBAdobe PDFView/Open
02_declaration.pdf73.38 kBAdobe PDFView/Open
03_certificate.pdf113.01 kBAdobe PDFView/Open
04_acknowledgements.pdf105.33 kBAdobe PDFView/Open
05_abstract.pdf87.97 kBAdobe PDFView/Open
06_preface.pdf90.11 kBAdobe PDFView/Open
07_contents.pdf166.4 kBAdobe PDFView/Open
08_list of tables.pdf90.85 kBAdobe PDFView/Open
09_list of figure s.pdf258.93 kBAdobe PDFView/Open
10_abbreviations.pdf46.99 kBAdobe PDFView/Open
11_chapter 1.pdf518.83 kBAdobe PDFView/Open
12_chapter 2.pdf586.71 kBAdobe PDFView/Open
13_chapter 3.pdf536.28 kBAdobe PDFView/Open
14_chapter 4.pdf1.8 MBAdobe PDFView/Open
15_chapter 5.pdf1.17 MBAdobe PDFView/Open
16_summary.pdf220.4 kBAdobe PDFView/Open
17_references.pdf478.59 kBAdobe PDFView/Open
18_appendix.pdf33.88 kBAdobe PDFView/Open

Items in Shodhganga are protected by copyright, with all rights reserved, unless otherwise indicated.