I= ACCELERATED BIODEGRADATION OF ENDOSULFAN IN SOIL AND WATER ENVIRONMENTS
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Title of Thesis
ACCELERATED BIODEGRADATION OF ENDOSULFAN IN SOIL AND WATER ENVIRONMENTS

Author(s)
SARFRAZ HUSSAIN
Institute/University/Department Details
Institute of Soil & Environmental Sciences/ University of Agriculture, Faisalabad Pakistan
Session
2008
Subject
Soil Science
Number of Pages
128
Keywords (Extracted from title, table of contents and abstract of thesis)
endosulfan in soil, accelerated biodegradation, organochlorine pesticides, chaetosartorya stromaloides, aspergillus terricola, aspergillus terreus, soil bacteria, fungal isolates, pseudomonas aeruginosa

Abstract
Extensive applications of persistent organochlorine pesticides like endosulfan on cotton have led to the contamination of soil and water environments at several sites in Pakistan, Microbial degradation offers an effective approach to remove such toxicants from the environment. Several strains of Bacteria and fungi were isolated from endosulfan contaminated soil. A total of 29 bacterial and 16 fungal strains were tested for their endosulfan degradation potential. The strains differed substantially in their potential to degrade endosulfan in vitro which ranged from 40 to 93% of the spiked amount (100 mg 1- 1 ) Biodegradation of endosulfan by these microorganisms also resulted in substantial decrease in pH of the brother from 8.2 to 3.2 within 14 days of incubation. High performance liquid chromatography analyses revealed that endosulfan diol and endosulfan ether were among the products of endosulfan metabolism by these microbial strains while endosulfan sulfate. A persistent and toxic metabolite of endosulfan was not detected in any case. The three strains of each of bacteria (Chaetosartorya stromaloides, Aspergillus terricola and Aspergillus terreus) were the most efficient degraders of both a-and B-endosulfan as they consumed more than 90% of the spiked amount (100mg 1-1) in the broth within 14 days of incubation. The results showed that endosulfan degradation by P. aeruginosa was most effectively achieved at an initial inoculum size of 600 (OD= 0.86). incubation temperature of 30 C in shaken slurries at p11 8 in loam soil. Biodegradation of endosulfan varied in different textured soils being more rapid in course textured soils than in fine textured soil. Exogenous application of organic acids (citric acid and acetic acid ) and amino acids (L-methionine and L-cystein ) had stimulatory and inhibitory effects respectively on biodegradation of endosulfan. The kinetics of endosulfan biodegradation by P aeruginosa was studied at its different initial concentrations by using different growth and non-growth linked models. It was observed that at initial endosulfan concentrations of 50 to 150 mg 1-1 Mond with growth model was well fitted into the data. The results of these studies may imply that these bacterial/fungal strains could be employed for bioremediation of endosulfan polluted soil and water environments.

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2185.82 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
385.18 KB
2 1 Introduction 3
99.91 KB
3 2 Review Of Literature 10
341.76 KB
  2.1 Endosulfan Production And Use 10
  2.2 Fate Of Endosulfan In Environment 12
  2.3 Persistence Of Endosulfan 19
  2.4 Endosulfan Toxicity 22
  2.5 Biodegradation Of Endosulfan 24
  2.6 Kinetics And Modeling Of Pesticides Biodegradation 32
  2.7 Characterization Of Genes Enzymes Responsible For Biodegradation Of Endosulfan 33
4 3 Materials And Methods 36
274.76 KB
  3.1 Collection Of Environmental Samples 36
  3.2 Reagents And Chemicals 36
  3.3 Isolation Of Microbial Strains Capable Of Degrading Endosulfan 38
  3.4 Biodegradation Of A €“And B-Endosulfan By Soil Bacteria 39
  3.5 Biodegradation Of Endosulfan By Fungal Isolates 42
  3.6 Optimization Of Environmental Parameters For Accelerated Biodegradation Of Endosulfan By Pseudomonas Aeruginosa 44
  3.7 Kinetics Of Endosulfan Biodegradation 49
  3.8 Extraction And Analytical Procedure For Endosulfan Detection 50
  3.9 Soil Analysis 52
5 4 Results 55
748.92 KB
  4.1 Biodegradation Of A And B-Endosulfan By Soil Bacteria 55
  4.2 Screening Of Soil Fungi For In Vitro Degradation Of Endosulfan 68
  4.3 Optimization Of Environmental Parameters For Biodegradation Of A €“And B-Endosulfan In Liquid Culture And Soil Slurry By Pseudomonas Aeruginosa 76
  4.4 Kinetics Of Growth Linked Biodegradation Of Endosulfan By Aeruginosa 92
6 5 Discussions 98
146.39 KB
  5.1 Biodegradation Of A €“And B-Endosulfan By Soil Bacteria 98
  5.2 Screening Of Soil Fungi For In Vitro Degradation Of Endosulfan 100
  5.3 Optimization Of Environmental Parmeters For Biodegradation Of A-And B-End In Liquid Culture And Soil Slurry By Aeruginosa 103
  5.4 Kinetics Of Growth Linked Biodegradation Of Endosulfan By Aeruginosa 106
7 6 Summary 108
63.61 KB
8 7 Concluding 111
295.09 KB
  7.1 Future Directions 111
  7.2 Literature Cited 113