Dissertation > Excellent graduate degree dissertation topics show

Prodction, Purification and Immobilization of a Thermoalkaliphilic Catalase from Thermoascus Aurantiacus

Author: KeZunZhu
Tutor: ChenXiaoLong；ZhangChaoZuo
School: Zhejiang University of Technology
Course: Biochemical Engineering
Keywords: Thermoascus aurantiacus thermoalkaliphilic catalase purification chitosan beads immobilization
CLC: TQ925
Type: Master's thesis
Year: 2011
Downloads: 50
Quote: 0
Read: Download Dissertation

Abstract


Catalase (EC 1.11.1.6) which presents in all aerobiccellsdecomposes hydrogen peroxide to molecular oxygen and water. It hasbeen applied in a wide field such as bleaching streams in textile and paperindustry, milk disinfection and clinical analysis. In this study, the mediumcomponents of Thermoascus aurantiacus were optimized and theelectrophoresis-grade enzyme was obtained after three prurification steps.The catalase was immobilized onto chitosan beads by the covalentbinding. The immobilized catalase showed higher pH stability andthermostability than the free catalase. And the properties of immobilizedcatalase and its application in removing H2O2 from bleaching streamswere studied. The results showed that this catalase has a potentialapplication in removing residual hydrogen peroxide in industrialbleaching processes.After three step treatments with (NH4)2SO4 fractionnal precipitation,salting-out and DEAE-Sepharose anion-exchange column, athermoalkaliphilic catalase from Thermoascus aurantiacus was purified.We gained 41.3% of the total activity and the specific activity of thecatalase was 4789 U/mg with 4.31 purification fold. The catalasedetermined by SDS-PAGE was composed of two identical subunits andhad a molecular mass of 190 kDa. The Km value for the purified catalase was 40.10 mmol·L-1 and the k2 value was 1.57×104μmol·(min mgprotein)-1. The catalase was highly active over a temperature range from25 to 75℃and a pH range from 7 to 13, having the optimum activity at65℃and pH 12. These results demonstrated that the catalase isthermoalkaliphilic.The immobilized catalase was immobilized onto chitosan supportusing glutaraldehyde as cross-linking agent. The Optimumimmobilization conditions for the immobilization were as follows: 250mg chitosan, cross-lingking temperature 40℃, reaction time 1h, 40ml0.75% glutaraldehyde, catalase 2000 U. The immobilized catalase activitywas 1700 U/g and the acitivity retaining yield of immobilized enzymewas 21.25%. The optimum temperature and pH of the immobilizedcatalase was 75℃and 12, respectively. It retained about 55% of its initialactivity after 13 repeated cycles during the total 130 min reaction time.

Related Dissertations

  1. Study on Protective Effects of Apple Polyphenol on Immune System Injury Caused by γ-Ray,S661.1
  2. Study on Wastewater Purification Effect of the Free Surface Wetland with Different Substrates and Plant Combination,X703
  3. Penicillium Expansum TS414 Lipase in Pichia Pastori: Expression, Purification and Enantioselective Esterification of (R, S)-naproxen,Q814
  4. Studies on Fermentation Optimization, Purification and Enzyme Characteristics of Lipase from Aspergillus Oryzae FS-1,TQ925.6
  5. Studies on Isolation, Purification and Chemical Structure for Polysaccharides from Camellia Chrysantha(Hu) Tuyama,S567.19
  6. Research of Glycosaminoglycan from Perna Virids Effect on Blood Lipid,R285.5
  7. Purification of Endogenous Proteases from (Litopenaeus Vannamei) Shrimp Head and Their Enzymology Properties,S985.21
  8. Study on the Preparation of the Low Molecular Weight Fuciodan from Sargassum Henslowianum (C.Agardh) and Anti-tumor Activity,TS254.9
  9. Under microaerobic conditions closed calcium carbide furnace exhaust COS gas adsorption purification,X781
  10. Studies on Extraction and Analysis of Fructooligosaccharides in Smallanthus Sonchifolius,TS255.1
  11. Experiment Study of the Biogas Purification Process by Zeolite Filling Washing,TQ221.11
  12. Optimization of Fermentation Conditions, Purification, Cloning and Expression of a Cold-active Lipase from Pseudomonas Sp.RT-1,TQ925
  13. Extraction, Purification and Antifungal Activity of Anthocyanins in Drop Fruits of Chinese Baberry,TQ914.1
  14. The Research on Immobilization of β-galactosidase and Production Technology of Low Lactose Milk,TS252.4
  15. Effects of Low Molecular Organic Acids on Immobilazition of Lead Ions by Nanosized Hydroxyapatite,S153
  16. Preliminary Research on Characterization of Thermophilic Protease Pasey and Helicase Htc16,Q814
  17. Study on the Separation and Purification Way of Arctiin from Fructus Arctii and the Effect of Arctiin on the Growth of Mice C2C12 Cells,S853.7
  18. Purification of Human Respiratory Syncytial Virus Fusion Protein with Immunomagnetic Microsphere Technology,R373
  19. Identification of Marine Sreptomyces Sp. GY-4 and Researches on Its Antimicrobial Substances,Q936
  20. Prokaryotic Expression and Purification of Human Beta-Defensin-9,Q78
  21. Study on Synthesis of Polysaccharide Tris (Phenylcarbamates) Derivatives as Chiral Stationary Phases (CSPs) and Estimation of Their Resolution Abilities,TQ460.1

CLC: > Industrial Technology > Chemical Industry > Other chemical industries > Fermentation industry > Enzyme preparation ( enzyme )
© 2012 www.DissertationTopic.Net  Mobile