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Title of Thesis

Quratulain Syed
Institute/University/Department Details
Institute of Chemistry/ University of the Punjab
Number of Pages
Keywords (Extracted from title, table of contents and abstract of thesis)
anaerobic fermentation, clostridium, acetobutylicum clostridium, acetobutylicum, dibutylphthalate, butanoj, chloramphenicol, solventogenesis, butanol toxicity

The acetone-butanol-ethanol fermentation by locally isolated culture of Clostridium acetobutylicum PCSIR-5 and its butanol resistant strain Clostridium acetobutylicum PCSIR-10 was investigated. The fermentation conditions initially in 3L flasks and then in scale up production (14L, 30L,. 50L, 100L, 300L and 500L fermenters) were optimized. The optimized fermentation medium consisted of (gL-1) cane molasses: 120.0 (6.0% sugar); (NH4)2SO4 :3.0; superphosphate; 0.7 and CaCO3 3.0. (pH: 6.2). The vegetative cells of Clostridium acetobutylicum at the rate of 3.0% (v/v) were used as inoculum. The fermentation was carried out under strict anaerobic and sterile conditions at 32±1°C for 96 hours. The amounts of total mixed solvents produced by parent and butanol resistant strain of Clostridium acetobutylicum were 15.2gL-1and19.2gL-1, respectively. The physiological and morphological changes during the course of acetone-butanol-ethanol fermentation were also studied. The fermentation methodologies adopted were batch, fed batch, extractive and immobilized. The performance of the selected culture was satisfactory in all the above fermentation techniques. The fed batch fermentation was found to be a promising technique as the duration of fermentation was reduced from 96 hours to 60 hours. The solvent production by extractive fermentation using dibutylphthalate was ecouraging (21.0 gL-l). The newly developed technology of cell immobilization was successfully employed for . acetone-butanol-ethanol fermentation. The maximum amount of solvents (20.0 GL-1) produced with cells immobilized in calcium alginate. Different antibiotics were added to the fermentation medium during scale up production in order to control the phage infection. Chloramphenicol was found to be the most effective antibiotic in controlling the phage infection. The results of present study indicate that the microbial production of acetone-butanol-ethanol solvents by using cane molasses as a substrate is more economical than through the chemical route.

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S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
346.38 KB
2 1 Introduction And Review Of Literature 1
414.78 KB
  1.1 Historical Background Of Abe Fermentation 2
  1.2 Microorganisms 5
  1.3 Raw Materials 8
  1.4 Biochemistry And Physiology Of Abe Fermentation 13
  1.5 Regulation Of Electron Flow 17
  1.6 Role Of Nutrient Limitation On Abe Fermentation 19
  1.7 Role Of Temperature And Oxygen On Abe Fermentation 19
  1.8 Triggering Of Solventogenesis 21
  1.9 Solventogenesis And Cell Differentiation 23
  1.10 Solventogenesis Culture Stability 24
  1.11 Butanol Toxicity To Micro-Organism 24
  1.12 Abe Fermentation By Immobilized Cell 26
  1.13 Contamination Problems During Abe Fermentation 28
  1.14 The Recovery Of Abe Solvents 30
  1.15 By Product Utilization 32
  1.16 Limitations Of The Conventional Batch Abe Fermentation 33
  1.17 Uses Of Abe Solvents 34
  1.18 Objectives Of The Work 37
3 2 Materials And Methods 38
262.44 KB
  2.1 Methodology 38
  2.2 Analysis 49
  2.3 Microscopic Examination 52
4 3 Results And Discussion 54
1876.24 KB
  3.1 Chemical Composition Of Black Strap Molasses 54
  3.2 Isolation Of Microorganisms 54
  3.3 Optimization Of Conditions For Fermentation 65
  3.4 Fermentation Profile Of Clostridium Acetobutylicum Pcsir-5 In 14-L Glass Stainless Steel Fermenter 82
  3.5 Morphological Changes In Colstridium Acetobutylicum Pcsir-5 During Abe Fermentation 86
  3.6 Production Of Abe Solvent By Fed-Batch Fermentation 90
  3.7 Effect Of Continuous Feeding Of Sugar On Abe Fermentation 92
  3.8 Development Of Butanol-Resitant Strain (Pcsir-100 100
  3.9 Effect Of Butanol On Membrane-Lipid Composition In Parent And Butanol Resistant Of Clostridum Acetobutylicum 113
  3.10 Effect Of Butanol On The Activity Of Membrane Bound Enzyme Atp-Ase In Parent And Butanol Resistant Strain Of Clostridium Acetobutylicum 118
  3.11 Immobilized Fermentation 121
  3.12 Extractive Fermentation 136
  3.13 Bacteriocin Production By Colstridium Acetobutylicum Pcsir-10 During Abe Fermentation 152
  3.14 Control Of Contamination In Abe Fermentation 152
  3.15 Scale- Up Production Of Abe Solvents By Clostridium Aacetobutylicum Pcsir-10 170
  3.16 Riboflavin Contents In The Stillage Of Abe Fermentation 173
  3.17 Slopping-Back-Process 176
  3.18 Down Stream Processing 178
5 4 References 182-215
577.69 KB
  4.1 Chromatograms A-G
  4.2 Summary
  4.3 List Of Publication