Dissertation > Excellent graduate degree dissertation topics show

Mechanisms Study of Feather Keratin Degradation by Bacillus Licheniformis NJU-1411-1 in Solid State Fermentation

Author: WangLing
Tutor: WangZuoYong
School: Nanjing University
Course: Microbial and Biochemical Pharmacy
Keywords: Feather keratin Biochemical degradation mechanisms Keratinase Sulfur compounds Thiolase role
CLC: S879.9
Type: Master's thesis
Year: 2011
Downloads: 42
Quote: 1
Read: Download Dissertation

Abstract


In this paper, the laboratory screening keratin efficient degradation strain - Bacillus licheniformis NJU-1411-1 strains studied, the use of solid state fermentation system, system studies before and after addition of exogenous sulfur compounds, biochemical indicators and 9 The kinds of sulfur compounds content. The results for further use of biotechnology development the feather keratin resources to understand the biochemical degradation of feather keratin mechanism laid a theoretical foundation. 1, NJU-1411-1 solid state fermentation feather keratin, one day logarithmic phase of cell growth. 2-5 days for the stationary phase of cell growth, fermentation after 5 days of cell growth into recession. NJU-1411-1 keratinase likely is an inducible enzyme, rapidly generate NJU-1411-1 logarithmic phase, and starts to decrease in stable phase. Keratinase play a key role in the process of NJU-1411-1-biodegradable feathers, the thiolase role turn deamination play a supporting role. 2, soluble protein content of fermented products continue to improve, continue to decline in the yield, especially in 1-3 days, the most obvious amplitude. Fermentation bottle can always be detected by the presence of NH3 in three days to reach up to the most active role in cell growth with stable transfer amino deamination. NH3 generation fermentation pH of the system increased gradually, weakly alkaline. 3, after the high temperature sterilization treatment, in feather extracts detected six kinds of sulfur compounds, and soluble proteins, indicating that the feather degradation has been started in the sterilization. After inoculation NJU-1411-1 was detected in the fermentation product to Class 7 of the sulfur compound: sulfate, thiosulfate, disulfide compounds, mercapto compounds, S-sulfocysteine ??like substances, sulfite , the free cysteine ??is not detected sulfide, free of cystine. The highest content of sulfates, thiosulfates, fermented NJU-1411-1 for the final product. S-sulfocysteine ??class of substances, the presence of sulphite, proved feather degradation thiolase exists, and in the growth period of recession, the role of the thiolase weakened. Does not detect the presence of free cysteine, suggesting that the action sites NJU-1411-1 the thiolase role keratinase solution, prefer a small molecular weight disulfide bonds such as cystine. Does not detect the presence of sulfide ions, suggesting that the rapid conversion of H2S to participate in the sulfite is converted to thiosulfate or directly released into the air. The study add 10μmol/ml 50μmol/ml 250μmol/ml sodium sulfite, sodium thiosulfate, DTT, biochemical indexes of influence on the fermentation, the results are as follows: (1) only add 1 Oμmol / ml sodium sulfite, sodium thiosulfate sodium sulfate, biomass ratio control increased slightly. Other add group biomass concentration lower than that of the control, but no more than an order of magnitude difference. (2) all add group enzyme activity higher than that of the control, 3 days, add 50μmol/ml thiosulfate highest activity for 780U / g, is 1.8 times. On the fifth day, to add 250μmol/mlDTT highest activity, hit 724.4 U / g, is 2.8 times. (3) Add 10μmol/ml, 50μmol/ml sodium sulfite 250μmol/ml the, 10μmol/ml 50μmol/mlDTT and 10μmol/ml of sodium thiosulfate, can significantly improve the fermentation products of soluble protein content. Speculated that the possible reasons for the three kinds of the sulfur-containing compound not only improve the keratinase Activity, and relying on its own restore to open the disulphide bonds of keratin, and to improve the degradation rate of the keratin protein content, soluble angle. 5 Add 10μmol/ml 50μmol/ml 250μmol/ml sodium sulfite, sodium thiosulfate, DTT, 9 kinds of the sulfur-containing compounds content of the results are as follows: (1) adding sodium sulfite, sodium thiosulfate, DTT was significantly improved FERMENT sulfate and thiosulfate content. (2) adding sodium sulfite, can significantly improve S-sulfocysteine ??class of substance content prove sulfite involved in the role of thiolase. Sodium thiosulfate, DTT may not be involved in the effect of thiolase, but is similar to the role of the thiolase is, reduction of disulfide bonds of the keratin molecule peripheral structure, so that the feather keratin exposes more thiolase role sites, an appropriate increase in the S-sulfonic acid cysteine ??content. (3) Add 50μmol/ml 250μmol/ml sodium sulfite, sodium thiosulfate, DTT, the fermentation products disulfide matter content, the sulfite content was significantly lower than the control, thiol compounds were significantly improved. Speculated joined the high concentrations of the three kinds of sulfur compounds, keratinase, live, disulfide bond reduction, thiolase role (sulfite participation) and other enhanced, resulting in more disulfide substance is reduced to a mercapto compound. 6 experimental results show that added of the 50μmol/ml sodium sulfite, both to a greater extent to improve the thiolase, improve the viability of the keratinase, integrated to improve NJU-1411-1 degradation feathers ability.

Related Dissertations

  1. Keratinase-protease One Bath Treatment of Wool for Anti-felting Finishing,TS195.56
  2. Expression of Keratinase Gene kerC from Bacillus Subtilis in Pichia Pastoris,S816.3
  3. Studies on Fast Analytical Method of Pesticide Multi-Residues in Sulfo-compounds Vegetables,S481.8
  4. The Study of Extractive Distillation Deep Desulfurization Process for FCC Gasoline,TE624.5
  5. Studies on Desulfurization of Hydrocarbon Using Organic Polymer,TE624.55
  6. The diesel Biodesulfurization of Isolation and characterization of bacteria,X701.3
  7. Biosynthesis of L-ascorbyl Aromatic Acid Ester and Studies on Microbial Keratinase,Q814
  8. STUDIES ON FEATHER-DEGRADING Flavobacterium breve ZDM,THE FERMENTATION CONDITIONS AND CHARACTERISTICS OF KERATINASE,Q939.9
  9. New nitrogen , sulfur lubricant additive synthesis, characterization and properties of,TE624.82
  10. The Study of Strain Screening, Fermentation and Purification of Keratinase,TQ925
  11. Exchange Fluxes of Volatile Organic Sulfur Compounds between Land Surfaces and Atmosphere in Selected Typical Terrestrial Ecosystems in the Pearl River Delta,X171
  12. For phase-change memory chalcogenide compounds and devices,TN304
  13. Containing new synthetic methods and reactivity studies of rare earth compounds of the machine sulfur ligands,O641.4
  14. Mechanism and Kinetics of a number of chemical reactions of sulfur compounds in the atmosphere,X131.1
  15. Heterogeneous Reactions between Airborne Sulfur Containing Compounds with Mineral Oxides and Atmospheric Particles,X513
  16. Expression of Trichophyton Mentagrophytes Keratinase and Researches on Their Biological Roles,R751
  17. Speciation of Sulfur Compounds and the Study of Reaction Mechanism in the Synthesis of Ammonium Thiocyanate,O657.7
  18. Enzymatic Modification of Wool Surface and Its Mechanism,TS131
  19. Preparation and Electrocatalytic Properties of Fe～（3+）, In～（3+）, Sb～（5+）, Co-doped SnO2 Electrode,O646.5
  20. Studies on Extracting New Methods of Feather Kertain,S879.9

CLC: > Agricultural Sciences > Livestock, animal medicine,hunting,silkworm,bee > Comprehensive utilization of livestock and poultry products > By - products and Its Utilization > Other
© 2012 www.DissertationTopic.Net  Mobile