Sen Biosurfactants

1. Auflage 2010
ISBN: 978-1-4419-5979-9
Verlag: Springer US
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, Band 672, 331 Seiten

Reihe: Advances in Experimental Medicine and Biology

The microbial world has given us many surprises including microbes that grow under extremely harsh conditions (122C at 40 MPa), novel metabolisms such as the uranium and perchlorate reduction, and novel chemicals that can be used to control diseases. We continually face new and difficult problems such as the need to transition to more carbon-neutral energy sources and to find eco-friendly chemicals and to find new drugs to treat disease. Will it be possible to tap into the seemingly limitless potential of microbial activity to solve our current and future problems?The answer to this question is probably yes. We are already looking to the microbial world to provide new energy sources, green chemicals to replace those made from petroleum, and new drugs to fight disease. To help us along these paths, we are deciphering how microorganisms interact with each other. We know that microbial populations interact and communicate with each other. The language that microbes use is chemical where small molecules are exchanged among different microbial cells. Sometimes, these chemicals suppress activities of competitors and could be used as antibiotics or may have other therapeutic uses. Other times, the chemicals stimulate complex responses in microbial populations such as fruiting body or biofilm formation. By understanding the conversation that microbes are having among themselves, e. g.

Ramkrishna Sen is an Assistant Professor (Bioprocess Engineering) in the Department of Biotechnology, Indian Institute of Technology (IIT) Kharagpur, India. Before joining IIT Kharagpur, Dr. Sen served BITS, Pilani as an assistant professor and Cadila Pharmaceuticals Ltd., Ahmedabad as the Manager (R&D-Biotech). He successfully completed some industrial projects and launched modern biotechnology products. In IIT Kharagpur, he currently heads the 'Bioprocess and Bioproduct Development' group, consisting of 11 research scholars, 2 MTech and 2 BTech project students, who are actively involved in developing, optimizing, modeling and scaling up bioprocesses for the production and applications of marine biosurfactants, probiotics based nutraceuticals, water-repellant durable jute geotextiles and biofuels. Dr. Sen, being a biochemical engineer with industrial R&D experience had set his research priorities in broader areas of biotherapy and bioenergy. His Biosurfactant group is engaged in characterizing marine microbial surfactants for their potential commercial, healthcare (antimicrobial and anticancer) and environmental (including bioremediation and MEOR) applications. His Nutraceutical group is developing probiotic based nutraceuticals and also working on probioactive molecules like bacteriocin and antihyperglycemic EPS molecule with significant antioxidant activities (Patent Application No.: 594/KOL/2009) and industrial enzymes. Dr. Sen was also involved in developing a biofuel additive for diesel engine, which showed superior fuel properties and pollution characteristics (Patent Appl. No.: KOL /1373/2006). His group is recently involved in developing hydrophobic geotextiles, continuous processes for biodiesel production (sponsored by PfP Technology LLC., Houston, USA) and process integration for bio-ethanol (in collaboration with NEERI, Nagpur) production. Dr. Sen has international research collaborations with some foreign universities and has visited many foreign countries including USA, UK , Brazil, Portugal, Czech Republic, Malaysia, Australia, etc. He has a number of sponsored research and consultancy projects and several research/review articles and book chapters in high impact international journals and highly rated books in the field of biotechnology and biochemical engineering. He serves as a reviewer of 17 peer reviewed international journals and has edited this book being published by Landes Biosciences and Springer Science+Business Media, LLC. Dr. Sen was recently invited as one of the founding members of the recently launched Global Biorenewables (BioEnergy) Research Society (GBR Society) in Lisbon. His biography has been published in Who's Who in Science & Engineering (2007) and Who's Who in the World (2008).

Autoren/Hrsg.

Sen, Ramkrishna

Inhaltsverzeichnis

1;Title Page;3
2;Copyright Page ;4
3;DEDICATION;5
4;FOREWORD;6
5;PREFACE;9
6;ABOUT THE EDITOR...;11
7;PARTICIPANTS;12
8;Table of Contents;18
9;Chapter 1 Screening Concepts for the Isolation of Biosurfactant Producing Microorganisms;26
9.1;Introduction;26
9.2;Sampling;27
9.3;Isolation;27
9.4;Screening Methods;28
9.4.1;Surface/Interfacial Activity;28
9.4.1.1;Direct Surface/Interfacial Tension Measurements;28
9.4.1.2;Du-Nouy-Ring Method;29
9.4.1.3;Stalagmometric Method;29
9.4.1.4;Pendant Drop Shape Technique;29
9.4.1.5;Axisymmetric Drop Shape Analysis by Profile;30
9.4.1.6;Measurements Based on Surface/Interfacial Tension;30
9.4.1.7;Drop Collapse Assay;31
9.4.1.8;Microplate Assay;31
9.4.1.9;Penetration Assay;31
9.4.1.10;Oil Spreading Assay;32
9.4.1.11;Emulsification Capacity Assay;32
9.4.1.12;Solubilization of Crystalline Anthracene;33
9.4.2;Cell Surface Hydrophobicity;33
9.4.2.1;Bacterial Adhesion to Hydrocarbons Assay (BATH);33
9.4.2.2;Hydrophobic Interaction Chromatography (HIC);33
9.4.2.3;Replica Plate Assay;34
9.4.2.4;Salt Aggregation Assay;34
9.4.3;Specialities;34
9.4.3.1;CTAB Agar Plate;34
9.4.3.2;Hemolysis;35
9.5;High Throughput Screening;36
9.6;Conclusion and Perspectives;36
9.7;References;37
10;Chapter 2 Molecular Genetics of Biosurfactant Synthesis in Microorganisms;39
10.1;Introduction;39
10.2;Important Aspects Pertaining to Biosurfactant Production in Microorganisms;40
10.3;Molecular Genetics of Biosurfactant Production in Bacteria;40
10.3.1;Acinetobacter Species;40
10.3.1.1;Emulsan;41
10.3.1.2;Apoemulsan;42
10.3.1.3;Alasan;44
10.3.1.4;Biodispersan;44
10.3.1.5;Exopolysaccharide (EPS);44
10.3.2;Pseudomonas Species;44
10.3.2.1;Bacillus Species;48
10.3.2.2;Serratia Species;50
10.4;Molecular Genetics of Glycolipid Synthesis in Fungi and Yeast;54
10.4.1;Candida;54
10.4.1.1;Mycobacterium, Corynebacteria, Rhodococcus;55
10.4.1.2;Pseudozyma, Ustilago maydis;55
10.5;Exploitation of Biosurfactant Molecular Genetics in Biotechnological Applications;56
10.6;Conclusion;58
10.7;Future Prospects;58
10.7.1;Acknowledgements;58
10.8;References;59
11;Chapter 3 Interaction of Dirhamnolipid Biosurfactants with Phospholipid Membranes: A Molecular Level Study;67
11.1;Introduction;67
11.2;Critical Micellar Concentration of diRL;68
11.3;Partitioning of DiRL into Phospholipid Membranes;70
11.4;Effect of Membrane Lipid Composition on Membrane Partitioning;70
11.5;Modulation of the Thermotropic Behavior of Phospholipids by diRL;71
11.6;Effect of diRL on Phospholipid Polymorphism;74
11.7;DiRL Affects Phospholipid Acyl Chain Mobility;75
11.8;Conclusion;76
11.9;References;77
12;Chapter 4 Microbial Surfactants and Their Potential Applications:An Overview;79
12.1;Introduction;79
12.2;Classification of Biosurfactants;79
12.2.1;Glycolipids;79
12.2.1.1;Trehalose Lipids;80
12.2.1.2;Rhamnolipids;80
12.2.1.3;Sophorolipids;80
12.2.1.4;Mannosylerythritol Lipids;80
12.2.2;Lipopeptides;80
12.2.2.1;Surfactin;80
12.2.2.2;Iturin;81
12.2.2.3;Fengycin;81
12.2.2.4;Lichenysin;81
12.2.3;Fatty Acid Biosurfactant;81
12.2.4;Polymeric Biosurfactants;81
12.2.4.1;Emulsan;81
12.2.4.2;Biodispersan;81
12.2.4.3;Alasan;82
12.2.4.4;Liposan;82
12.2.4.5;Emulsifying Biopolymer from Fungus;82
12.2.5;Emulsifying Protein;82
12.2.6;Particulate Biosurfactant;82
12.3;Potential Applications of Biosurfactant;82
12.3.1;Role of Microbial Surfactants in Bioremediation of Oil Pollutants;82
12.3.2;Application of Biosurfactant in Petroleum Industry;83
12.3.2.1;Biosurfactant in Oil Clean Up of Storage Tanks;83
12.3.2.2;Microbial Surfactants in Microbial Enhanced Oil Recovery (MEOR);83
12.3.3;Use of Biosurfactants in Food Industries;84
12.3.4;Use of Biosurfactants in Agricultural Sectors;84
12.3.5;Application of Biosurfactant as a Substitute of Synthetic Chemical Surfactant in Commercial Laundry Detergents;84
12.3.6;Biosurfactant as Biopesticide;84
12.3.7;Use of Biosurfactants in Pharmaceutical Sectors and Molecular Biology Research;85
12.4;Conclusion;85
12.5;References;85
13;Chapter 5 Microbial Biosurfactants and Biodegradation;90
13.1;Introduction;90
13.2;Accession of Hydrophobic Contaminants in Aqueous Media;91
13.3;Impact of Micellization on Access;93
13.4;Accession of Hydrophobic Contaminants in Soil;94
13.5;Physiological and Morphological Changes Due to Surfactant Activity;95
13.6;Biofilm Formation and Detachment;96
13.7;Conclusion;97
13.8;References;97
14;Chapter 6 Biomedical and Therapeutic Applications of Biosurfactants;100
14.1;Introduction;100
14.2;Biomedical and Therapeutic Applications of Biosurfactants;101
14.3;Biological Activity;101
14.3.1;Glycolipids;101
14.3.2;Lipopeptides;104
14.3.3;Other Biosurfactants;106
14.4;Anti-Adhesive Activity;107
14.5;Antimicrobial Activity;107
14.6;Conclusion;108
14.7;References;108
15;Chapter 7 Microbial Surfactants of Marine Origin: Potentials and Prospects;113
15.1;Introduction;113
15.2;Marine Biosurfactants and Bioemulsifiers;114
15.2.1;Exopolysaccharide Biosurfactants;114
15.2.2;Glycolipopeptides and Carbohydrate-Lipid-Protein Complexes;117
15.2.3;Glycolipids;117
15.2.4;Lipopeptides;119
15.3;Environmental and Industrial Potentials;120
15.4;Biological Action of the Marine Biosurfactants;123
15.5;Conclusion;125
15.6;References;125
16;Chapter 8 Biomimetic Amphiphiles: Properties and Potential Use;127
16.1;Introduction;127
16.1.1;Scope;129
16.1.2;Surfactant Basis;129
16.1.3;Specific Classes of Surfactants;130
16.1.3.1;Cationics;131
16.1.3.2;Non-Ionics;131
16.1.3.3;Zwitterionics;131
16.2;Surface Active Compounds are Ample in Nature;132
16.3;Self-Assembly Processes;133
16.4;Association Colloids;133
16.4.1;Micelles;134
16.4.1.1;Classical Theories of Micelle Formation;135
16.4.1.2;Micelles and Ahead;135
16.4.2;Emulsification;135
16.5;Biosurfactants and Their Potential Uses;136
16.5.1;Activity of Biosurfactants;136
16.5.2;Classification of Biosurfactants;137
16.5.2.1;Glycolipids;137
16.5.2.2;Lipopeptides and Lipoprotiens;138
16.5.2.3;Fatty Acids, Neutral Lipids, Phospholipids;139
16.5.2.4;Polymeric Surfactants;139
16.5.2.5;Particulate Biosurfactants;139
16.5.3;Properties of Biosurfactants;140
16.5.3.1;Surface and Interfacial Activity;140
16.5.3.2;Temperature, pH and Ionic Strength Tolerance;140
16.5.3.3;Biodegradability;140
16.5.3.4;Emulsion Forming and Emulsion Breaking;140
16.5.3.5;Chemical Diversity;141
16.5.3.6;Low Toxicity;141
16.5.4;Potential Applications of Biosurfactants;141
16.5.4.1;Microbial Enhanced Oil Recovery (MEOR);141
16.5.4.2;Hydrocarbon Degradation;141
16.5.4.2.1;Hydrocarbon Degradation in the Soil Environment;141
16.5.4.2.2;Hydrocarbon Degradation in Aquatic Environment;142
16.5.4.3;Biosurfactant and HCH Degradation;142
16.6;Association Properties of Biosurfactants;142
16.7;Toxological and Ecological Aspects of Surfactants;143
16.7.1;Dermatological Aspects;143
16.7.2;Aquatic Toxicity;143
16.7.3;Bioaccumulation;143
16.7.4;Biodegradability;144
16.8;Conclusion;144
16.9;References;144
17;Chapter 9 Applications of Biological Surface Active Compounds in Remediation Technologies;146
17.1;Microbial Surface Active Compounds;146
17.1.1;Structures and Properties;146
17.1.2;Novel Microbial Surface Active Compounds;147
17.2;The Roles of SACs in Hydrocarbon Metabolism;148
17.2.1;Microbial Access to Hydrocarbons;148
17.2.2;Altering Access Mode;149
17.3;Remediation Technologies;149
17.3.1;Bioremediation;151
17.3.1.1;Emulsification;151
17.3.1.2;Micellarization;151
17.3.1.3;Regulation of Adhesion-Deadhesion of Microorganisms to Hydrocarbons;151
17.3.1.4;Desorption of Contaminants;155
17.3.2;Soil Washing;155
17.3.2.1;Hydrocarbon Contaminated Soils;155
17.3.2.2;Metal Contaminated Soils;156
17.3.3;Conclusion and Prospects;156
17.3.4;References;156
18;Chapter 10 Possibilities and Challenges for Biosurfactants Use in Petroleum Industry;160
18.1;Introduction;160
18.2;Surfactants and Biosurfactants in Petroleum Industry;161
18.3;Microbial Enhanced Oil Recovery;161
18.4;Injection of Ex Situ Produced Biosurfactants into Oil Reservoirs;162
18.5;Injection of Laboratory-Selected Biosurfactant-Producing Microorganisms into Oil Reservoirs;162
18.6;Stimulation of Indigenous Biosurfactant-Producing Microorganisms within Oil Reservoirs;163
18.7;MEOR Field Trials;163
18.8;Crude Oil Transportation in Pipeline;164
18.9;Clean-Up of Oil Co U ntainers/Storage Tanks;165
18.10;Formulation of Petrochemicals;166
18.11;Conclusion and Future Perspectives;168
18.12;References;169
19;Chapter 11 Bacterial Biosurfactants, and Their Role in Microbial Enhanced Oil Recovery (MEOR);171
19.1;Introduction;171
19.2;Biosurfactant Producing Bacteria;172
19.3;Selection of Biosurfactant Producer;172
19.4;Factors Affecting Production of Biosurfactants;173
19.5;Factors Affecting Biosurfactant Production;173
19.6;Biosurfactant Production by Extremophiles;174
19.7;Recovery of Biosurfactant;175
19.8;Biosurfactant Production by Biotransformation;176
19.9;Improved Strains for Biosurfactant Production;176
19.10;Biosurfactants and Microbial Enhance Oil Recovery (MEOR);177
19.10.1;Types of MEOR;177
19.10.2;The Science of MEOR;177
19.11;Conclusion and Future Perspectives;178
19.12;References;179
20;Chapter 12 Molecular Engineering Aspects for the Production of New and Modified Biosurfactants;183
20.1;Introduction;183
20.2;Lipopetides as Targets for Engineering;184
20.3;Common Strategies for the Engineering of Biosurfactants;186
20.4;Surfactin and Daptomycin as Case Studies for Applied Lipopetide Engineering;188
20.5;Problems and Considerations for Biosurfactant Engineering;190
20.6;Future Aspects for Lipopeptide Engineering as Revealed by Recent Structural Details;191
20.7;Conclusion;192
20.8;References;193
21;Chapter 13 Rhamnolipid Surfactants: Alternative Substrates, New Strategies;195
21.1;Introduction;195
21.2;Substrates;196
21.3;Integrated Systems;198
21.4;Physicochemical Properties;199
21.4.1;Rhamnolipid Solutions;199
21.4.2;Emulsions and Microemulsions;200
21.4.3;Wetting Properties;201
21.4.4;Effect of Electrolytes;201
21.4.5;Effect of pH on Aggregation Morphology;202
21.4.6;Foam Film;203
21.5;Applications;203
21.5.1;Biosurfactants and Petroleum;203
21.5.2;BioSurfactants and Heavy Metals;204
21.5.3;Rhamnolipids and Antimicrobial Activity;204
21.5.4;Biosurfactants in Food, Cosmetics and Pharmaceuticals;205
21.6;Conclusion;206
21.7;References;207
22;Chapter 14 Selected Microbial Glycolipids: Production, Modification and Characterization;210
22.1;Introduction;210
22.2;Glycoglycerolipids;210
22.2.1;General Information;210
22.2.2;Glycoglycerolipids from Eukaryotic Cells;211
22.2.3;Glycoglycerolipids from Prokaryotic Cells;212
22.2.4;Glycoglycerolipids from Synthetical Route;212
22.2.5;Selected Glycoglycerolipids from Prokaryotes;213
22.2.5.1;Molecular Structures;213
22.2.5.2;Production, Downstream Processing and Analysis;213
22.2.5.2.1;Glucosylmannosyl-Glycerolipid fromMicrobacterium Spec. DSM 12583;213
22.2.5.2.2;Dimannosyl-Glycerolipid fromMicrococcus Luteus (Hel 12/2);216
22.2.5.2.3;Diglucosyl-Glycerolipid from Bacillus pumilus Strain AAS3;216
22.2.5.3;Chemo-Enzymatic Modification of Glycoglycerolipids;217
22.3;Oligosaccharide Lipids;218
22.3.1;General Information;218
22.3.2;Selected Oligosaccharide Lipids;220
22.3.2.1;Molecular Structures;220
22.3.2.2;Production, Downstream Processing and Analysis;220
22.3.2.2.1;Oligosaccharide Lipids from Tsukamurella Spec. DSM 44370;220
22.3.2.2.2;Pentasaccharide Lipids from Nocardia corynebacteroides SM1;222
22.3.2.3;Chemo-Enzymatic Modification of Oligosaccharide Lipids from Tsukamurella spec;223
22.4;Physico-Chemical and Bioactive Properties;223
22.5;Conclusion;225
22.6;References;225
23;Chapter 15 Production of Microbial Biosurfactants by Solid-State Cultivation;228
23.1;Introduction;228
23.2;Microbial Biosurfactants That It Would Be Interesting to Produce at Large Scale;229
23.3;Production of Biosurfactants by Classical Submerged Cultivation Is Problematic;229
23.4;Solid-State Cultivation as an Alternative Cultivation Technique with Potential for Biosurfactant Production;230
23.5;What Is the State of the Art of Biosurfactant Production in Solid-State Cultivation?;230
23.6;What Challenges Do We Face in the Production of Biosurfactants by Solid-State Cultivation?;232
23.6.1;Bioreactor Selection;232
23.6.2;What Will Be the Best Substrate to Use?;233
23.6.3;Downstream Processing;233
23.6.4;Monitoring of the Cultivation Process;234
23.7;Conclusion;234
23.8;References;234
24;Chapter 16 Rhamnolipid Biosurfactants: Production andTheir Potential in Environmental Biotechnology;236
24.1;Introduction;236
24.2;Chemical Structures and Properties of Rhamnolipid Biosurfactants;237
24.3;Biosynthesis of Rhamnolipid Biosurfactants;239
24.4;Production of Rhamnolipid Biosurfactants;239
24.5;Potential Applications of Rhamnolipid Biosurfactants;242
24.6;Conclusion and Future Perspectives;243
24.7;References;243
25;Chapter 17 Biosurfactant’s Role in Bioremediation of NAPL and Fermentative Production;247
25.1;Introduction;247
25.2;Bioremediation;248
25.2.1;What Are Non-Aqueous Phase Liquids (NAPL)?;248
25.2.2;Chemical Surfactants and Bioremediation;249
25.2.3;Biosurfactants and Bioremediation;250
25.3;Fermentative Production and Recovery of Biosurfactants;250
25.3.1;Production of Biosurfactants;251
25.3.2;Recovery of Biosurfactants;252
25.3.3;Economical Commercial Production;252
25.3.3.1;The Use of Cheaper Waste Substrates;253
25.3.3.2;Development of Efficient Fermentation Processes;254
25.3.3.2.1;Media and Process Optimization;254
25.3.3.2.2;Recovery Processes;256
25.4;Conclusion;256
25.5;References;257
26;Chapter 18 Biosurfactants from Yeasts: Characteristics, Production and Application;261
26.1;Introduction;261
26.2;Biosurfactant Classification and Characteristics;262
26.3;Production Processes;263
26.3.1;The Influence of the Culture Medium Composition;263
26.3.1.1;Carbon Source;264
26.3.1.2;Carbon Source from Renewable Resources;265
26.3.1.3;Nitrogen Source;266
26.3.2;The Environmental Factors Affecting the Production;267
26.3.2.1;pH;267
26.3.2.2;Temperature;267
26.3.2.3;Aeration and Agitation;270
26.3.3;Kinetics and Operation of Biosurfactant Production Process;270
26.4;Potential Commercial Applications;271
26.5;Conclusion;272
26.6;References;272
27;Chapter 19 Environmentally Friendly Biosurfactants Produced by Yeasts;275
27.1;Introduction;275
27.2;Culture Conditions for the Production of Biosurfactants;277
27.3;Substrates Used for the Production of Candida Biosurfactant;277
27.4;Emulsifying Activities, Surface Tension and Critical Micellar Concentration (CMC) of Candida Biosurfactants;277
27.5;Biosurfactant: Isolation Methodology and Yields;278
27.6;Biochemical Composition and Application of Biosurfactant;279
27.7;Trends and Future Challenges of Biosurfactants;280
27.7.1;Computer-Based Tools for Optimization and Cost Reduction;280
27.7.2;Experimental Design and Surface Response Methodology;280
27.7.3;Novel Tools in Biosurfactant Production, Control and Optimization Processes: Application of an Artificial Neural Network;281
27.8;Conclusion;281
27.9;References;282
28;Chapter 20 Synthesis of Biosurfactants and Their Advantages to Microorganisms and Mankind;286
28.1;Introduction;286
28.2;Surfactants and Biosurfactants;287
28.3;Significance and Role of Biosurfactants to Microbes;290
28.3.1;Adhesion;290
28.3.2;Emulsification;291
28.3.3;Bioavailability and Desorption;292
28.3.4;Defense Strategy;292
28.4;Advantages of Biosurfactants;293
28.4.1;Biodegradability and Controlled Inactivation of Microbial Surfactants;293
28.4.2;Selectivity for Specific Interfaces;293
28.4.3;Surface Modification;293
28.4.4;Diversity of Microbial Surfactants;293
28.4.5;Toxicity;293
28.5;Biosurfactants Types and Producing Organisms;293
28.6;Applications of Biosurfactants;294
28.6.1;Biosurfactant and Environment;294
28.6.2;Biosurfactants and Medicine;299
28.6.3;Biosurfactants and Miscellaneous Applications;299
28.7;Conclusion;300
28.8;References;300
29;Chapter 21 Enrichment and Purification of Lipopeptide Biosurfactants;306
29.1;Introduction;306
29.2;Properties of Biosurfactants Useful in Separation;306
29.3;Separation by Precipitation;307
29.4;Liquid Partitioning;307
29.4.1;Direct from Cell Culture;307
29.4.2;Solvent Extraction as a Means of Purification;307
29.5;Membrane Filtration;308
29.6;Cross Flow Ultrafiltration;308
29.7;Liquid Membranes;308
29.8;Foam Fractionation;308
29.9;Surface Skimming;310
29.10;Surface Enrichment;311
29.11;Adsorption to Solids;311
29.11.1;High Performance Liquid Chromatography;311
29.12;Conclusion;311
29.13;References;312
30;Chapter 22 Production of Surface Active Compounds by Biocatalyst Technology;314
30.1;Introduction;314
30.2;Biocatalysis;315
30.3;Enzymatic Synthesis of Monoglycerides;316
30.4;Synthesis of Sugar Esters;318
30.5;Synthesis of Fatty Acid Amides;320
30.6;Enzymatic Synthesis of Alkyl Glycosides;321
30.6.1;Yeast and Fungal Glucosidases;322
30.6.2;Plant Derived Glucosidases;323
30.6.3;Glucosidases Derived from Bacteria;323
30.7;Enzymatic Synthesis of Phospholipids;323
30.7.1;Enzymatic Production of Lysophospholipids;324
30.7.2;Enzymatic Production of Modified or Structured Phospholipids;325
30.8;Conclusion;326
30.9;References;326
31;Chapter 23 Structural and Molecular Characteristics of Lichenysin and Its Relationship with Surface Activity;329
31.1;Introduction;329
31.2;Surfactin;330
31.3;Nonribosomal Peptide Synthesis;332
31.4;Lichenysin Structure;332
31.5;Lichenysin Operon;335
31.6;Lichenysin Synthetase;336
31.7;Structure-Activity Relationship;337
31.8;Conclusion;338
31.9;References;338
32;Chapter 24 Surfactin: Biosynthesis, Genetics and Potential Applications;341
32.1;Introduction;341
32.2;Biosynthesis of Surfactin;342
32.2.1;Biochemistry and Mechanisms;342
32.2.2;Role of Genetic Regulations in Surfactin Biosynthesis;343
32.3;Potential Commercial Applications;343
32.3.1;Health-Care and Bio-Control Applications;343
32.3.2;Environmental Applications;345
32.4;Conclusion;345
32.5;References;345
33;Index;349