Dissertation > Excellent graduate degree dissertation topics show

Breeding, Fermentation and Extraction of High Poly-β-Hydroxybutyrate Production Strain

Author: JiAiYun
Tutor: CuiZhiFang
School: Shandong University of Science and Technology
Course: Chemical processes
Keywords: poly-β-hydroxybutyrate (PHB) breeding Zoogloea itzigohn fermentation extraction
CLC: TQ920.1
Type: Master's thesis
Year: 2010
Downloads: 116
Quote: 0
Read: Download Dissertation

Abstract


As an endogenetic macromolecular polymer accumulated in microorganism under nutritional imbalance condition, biocompatible and biodegradable poly-β-hydroxybutyrate (PHB) possesses similar properties to chemical synthetic plastics, thus could be used as a raw material of biodegradable plastics. Under the background of increasingly serious white pollution, PHB produced by microorganism becomes current research focus at home and abroad.Combining Nile blue plate with the Sudan black stain, PHB producing strains were successfully screened from the sewage. The selected strains were secondarily screened by flask fermentation. No.13 strain with 0.57g/L PHB production was selected as the starting bacterium for further study.Cell morphology, cultural features, physiological and biochemical characteristics, utilization of different carbon and nitrogen resources of NO.13 strain were studied. Based on the Bergy’s Manual of Determinative Bacteriology, the strain was identified as Zoogloea itzigohn and named Z-13.Z-13 was bred by UV mutation with 12W UV lamp,10cm vertical distance and 110s irradiation. Positive mutational strains with higher yield were studied for hereditary stability. A strain named uZ-14 with 0.57g/L PHB production (increased by 36.84%) was used for further fermentation optimization.Factors affecting the PHB production from uZ-14 were studied. The results showed that the best carbon resource was glucose and the best nitrogen resource was ammonium sulfate. The optimal conditions were lOg glucose,0.2g MgSO4·7H2O,1.5g K2HPO4,1.8g Na2HPO4·12H2O,0.2g (NH4)2SO4,0.01g CaCl2-2H2O and 1ml microelement solution (/L medium),3% inoculation amount and 30ml liquid volume in 250ml flask, pH7.2,30℃, 150r/min for 24h. After optimization,1.08g/L PHB could be got which was increased by 38.46%.The PHB extraction methods were further researched which showed that SDS/NaClO-chloroform was the best. Dry biomass/SDS solution (4g/L SDS) was 1%(w/v),30℃for 30min. The precipitation was got after centrifugation. The same volume NaCIO solution (2.84% active chlorine, pH12) was added,30℃for 30min. After centrifugation, the precipitation was finally extracted by chloroform. PHB concentration was 40.25% and molecular weight was 1206205. In this way, higher PHB extraction rate with little PHB degradation could be got.The extracted PHB and PHB standard were analyzed by ultraviolet spectrum (UV), infrared spectrum (IR) and gas chromatography (GC). The result showed the extracted PHB produced by uZ-14 was PHB and thus could be used as raw material of biodegradable plastics.

Related Dissertations

  1. Research on Automatic Detection Algorithm for Substructure Distress of Highway Pavement Based on SVM,U418.6
  2. ISAR Imaging Simulation of Space Targets and Target Recognition Based on ISAR Images,TN957.52
  3. Research of Question Answering System Based on the Analysis of Lexical and Semantic Meanings,TP391.1
  4. Research on Feature Extraction and Classification of Pulse Waveform for Cholecystitis and Nephrotic Syndrome Diagnosis,TP391.41
  5. Application of Q-Learning in the Content-Based Image Retrieval Technology,TP391.41
  6. Answer Extraction Based on Logic Representation and Reasoning for Reading Comprehension,TP391.1
  7. Research on Domain Entity Attribute and Event Extraction Technology,TP391.1
  8. Research on Transductive Support Vector Machine and Its Application in Image Retrieval,TP391.41
  9. Research on Feature Extraction and Classification of Tongue Shape and Tooth-Marked Tongue in TCM Tongue Diagnosis,TP391.41
  10. Research on Temporal Information Recognition and Normalization,TP391.1
  11. Context-Dependent Lexical Paraphrasing,TP391.1
  12. Research on Extraction and Tracking of People’s Opinion,TP391.1
  13. The Study of Domain Dictionary Construction Based on Web,TP391.1
  14. Research on Visual Measurement for Spacecraft Rendezvous and Approach,TP391.41
  15. Research on the Image Real-Time Acquisition, Storage and Image Processing System,TP391.41
  16. Feature Extraction, Selection and Combination in Lipreading,TP391.41
  17. Multi-currency Notes Technology Research and Implementation,TP391.41
  18. The Research on Paper Currency Classification Method Based on Harr-Like Feature and Minimal Ball Including Samples,TP391.41
  19. Pavement Distress Recognition Based on Image,TP391.41
  20. Haihong Fruit Vinegar Processing Technology,TS264.22
  21. Penicillium Expansum TS414 Lipase in Pichia Pastori: Expression, Purification and Enantioselective Esterification of (R, S)-naproxen,Q814

CLC: > Industrial Technology > Chemical Industry > Other chemical industries > Fermentation industry > General issues > Basic theory
© 2012 www.DissertationTopic.Net  Mobile