I= STUDIES ON THE PRODUCTION OF THERMOSTABLE PULLULANSE BY BACILLUS SPECIES
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Title of Thesis
STUDIES ON THE PRODUCTION OF THERMOSTABLE PULLULANSE BY BACILLUS SPECIES

Author(s)
Javed Iqbal
Institute/University/Department Details
Institute of Chemistry/ University of the Punjab
Session
1994
Subject
Chemistry
Number of Pages
260
Keywords (Extracted from title, table of contents and abstract of thesis)
thermostable pullulanse, bacillus species, extracellular pullulanase, bacillus subtilis, starch

Abstract
Therrnophilic bacterial culture capable of producing extracellular pullulanase was isolated from the soil. The culture was identified as a strain of Bacillus subtilis. The productivity of strain was improved by using UV-irradiation and alkylating agents. Maximum enzyme activity was achieved after 48 hours of shaking cultivation at 35 °C with an initial pH of 6.2. The production of enzyme pullulanase was significantly enhanced in the presence of liquefied starch, malt extract or tryptone in the medium The maximum production of pullulanase was observed with corn meal. Enzyme synthesis was stimulated by Mn2+; but not with Ca2+. At aeration rate of 1 L/ L/ min. with agitation of 200 rpm the el1zyrne activity was maximum. The optimum cultural conditions in solid state fermentation were incubation time 48 hour, thickness of bran layer 1.8 cm, moisture level 68%.Supplenlentation of wheat bran with various carbohydrates or nitrogen sources did not enhance the enzyme synthesis. The enzyme pullulanase was used together with amyloglucosidase to improve the efficiency of starch conversion to glucose. The enzyme was most active and stable in pH range 5.5-7.5 and 5.59.0 respectively. Pullulanase was stable at 70OC for 60 minutes at pH 6.2 in the presence of 5% starch. The activity of pullulanase was enhanced by the addition of 1. 6 m M Ca2+

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2977.31 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
246.73 KB
2 1 Introduction 1
259.26 KB
  1.1 Structure Of Starch 7
  1.2 Starch Hydrolyzing Enzymes 11
  1.3 Starch Hydrolysis 13
  1.4 Objectives 17
3 2 Review Of Literature 18
417.2 KB
  2.1 Pullulanase From Bacillus Species 21
  2.2 Pullulanase From Other Species 26
  2.3 Purification And Characterization 30
  2.4 Hydrolysis 35
  2.5 Action Pattern Of Pullulanse 40
  2.6 Immobilization 41
4 3 Materials And Methods 45
209.65 KB
  3.1 Materials 45
  3.2 Methods 46
  3.3 Analysis 52
  3.4 Fermentation Studies 54
  3.5 Culture Media 58
  3.6 Isolation And Purification 60
  3.7 Characteristics 61
  3.8 Vinetic Studies
5 4 Results 63
1127.04 KB
  4.1 Isolation Of Microorganisms 63
  4.2 Screening Of Microorganisms 65
  4.3 Identification Of The Selected Strain 65
  4.4 Culture Improvement 67
  4.5 Submerged Fermentation In Shake Flask 70
  4.6 Production Of Pullulanse In Stirred Fermenters 128
  4.7 Studies In 14 L Stirred Fermenter 125
  4.8 Solid State Fermentation 128
  4.9 Hydrolysis Of Starch 146
  4.10 Characteristics
  4.11 Determination Of Michaelis Menten Constant 167
6 5 Discussion 172-191
273.44 KB
7 6 Summary 192-195
407.02 KB
  6.1 References 196-225