Biological Activities of Extracts and Isolated Compounds from Bauhinia Galpinii (Fabaceae) and Combretum Vendae (Combretaceae) As Potential Antidiarrhoeal Agents

Biological activities of extracts and isolated compounds from Bauhinia galpinii (Fabaceae) and Combretum vendae (Combretaceae) as potential antidiarrhoeal agents

Ahmed Aroke Shahid

Declaration

Dedication

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Acknowledgements

Table of Contents Abstract

List of abbreviations

List of figures

List of tables

List of appendix

CHAPTER ONE Gastrointestinal disorders in diarrhoea diseases mechanisms and medicinal plants potentiality as therapeutic agents 1.0. Introduction 1.1. Plant metabolites as potential therapeutic agent 1.2. Aims 1.3. Specific objectives 1.4. Hypothesis CHAPTER TWO 2.0 Literature review 2.1. Diarrhoea as a disease 2.2. Pathophysiology of Diarrhoea 2.3. Detailed pathophysiology of diarrhoea 2.3.1. Inflammation in diarrhoea 2.3.2. Oxidative damage in diarrhoea 2.3.3. Enteric nervous system in diarrhoea 2.3.4. Cystic fibrosis transmembrane conductance regulator (CFTR) regulation 2.4. Specific Agents of Diarrhoea scherichia coli Staphylococcus aureus Campylobacter jejuni Shigella Vibrio cholerae Bacillus cereus Yersinia enterocolitica Listeria monocytogenes

Clostridium Salmonella typhimurium Enterococcus faecalis Candida albicans 2.6. Viral induced diarrhoea 2.7. Protozoa induced diarrhoea . Giardia intestinalis Entamoeba histolytica Cryptosporidium parvum Cyclospora cayetanensis 2.8. Parasitic induced diarrhoea Trichinella spiralis 2.9. Immune disordered induced diarrhoea 2.10. Antibiotic therapy induced diarrhoea 2.11. Diabetic complications induced diarrhoea 2.12. Food allergy induced diarrhoea 2.13. Potential mechanisms in the control of diarrhoea 2.14. Plants as potential source of therapeutic agents in alleviating diarrhoeal symptoms 2.15. Classification of phytochemicals with antidiarrhoea potential

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2.16. Ethnobotany and scientific investigation of plant species used traditionally in treating diarrhoea in South Africa 2.17.Conclusion CHAPTER THREE Plant selection, collection, extraction and analysis of selected species 3.1. Introduction 3.2. Solid-liquid extraction 3.3. Liquid-liquid fractionation 3.4. Thin layer chromatography (TLC) 3.5. Materials and Methods 3.6. Quantification of the phenolic constituents of the extracts 3.7. Results 3.8. Discussion 3.9. Conclusion CHAPTER FOUR Antimicrobial activities of the plant extracts against potential diarrhoeal pathogens 4.0. Introduction

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4.1. Qualitative antimicrobial (Bioautography) assay 4.2. Quantitative antimicrobial activity (Minimum inhibitory concentration (MIC)) assay 4.3.Selection of microorganisms used in the study 4.4. Material and Methods 4.5. Results 4.6. Discussion 4.7. Conclusion CHAPTRER FIVE Free radical scavenging and antioxidant activities of the extracts and fractions as antidiarrhoeal mechanism 5.1. Introduction 5.2. Antioxidant assays 5.2.2. The chemistry of some common antioxidant assays 5.3. Materials and Methods

5.4. Result

) 5.5. Discussion 5.6. Conclusion CHAPTER SIX Anti-inflammatory activities of the crude extracts as antidiarrhoeal mechanisms 6.0. Introduction 6.1. Effect of cyclooxygenases (COX) on GIT 6.2. Effects of lipoxygenase (LOX) on GIT 6.3. Effects of cytokines on GIT 6.4. Oxidative species as inflammatory mediator 6.5. Allopathic anti-inflammatory therapies and adverse effects on GIT 6.6. Plant phytochemicals as anti-inflammatory agents 6.7. Mechanisms of anti-inflammatory assay models 6.8. Materials and Methods 6.8.1. COX assay 6.8.2. LOX assay 6.9. Results 6.9.1. COX 6.9.2. LOX 6.10. Discussion 6.10.1. COX 6.10.2. LOX 6.11. Conclusion

CHAPTER SEVEN Cytotoxicity evaluation of the crude extracts against Vero African green monkey kidney cell lines 7.0. Introduction 7.1. Materials and Methods 7.1.1. Preparation of plant extracts 7.1.2. Cytotoxicity assay against Vero cell 7.2. Results 7.3. Discussion 7.4. Conclusion CHAPTER EIGHT Motility modulation potential of Bauhinia galpinii and Combretum vendae phenolic-enriched leaf extracts on isolated rat ileum 8.0. Introduction 8.1. Drugs and reagents 8.2. Animal care 8.2.1. Isolated ileum preparation 8.3. Contractility test 8.3.2. Spasmolytic assays 8.4. Data analysis 8.5. Results B. galpinii C. vendae 8.6. Discussion 8.7. Conclusion CHAPTER NINE Isolation and characterization of antimicrobial and antioxidant compounds from Bauhinia galpinii and Combretum vendae 9.0. Introduction 9.2. Materials and Methods

C. vendae C. vendae B. galpinii B. galpinii B. galpinii 9.4. Characterization of the isolated compounds 9.5. Results C. vendae C. vendae B. galpinii B. galpinii 9.6. Discussion C. vendae B. galpinii 9.7. Conclusion CHAPTER 10 General conclusion and future prospects 10. Introduction 10.1. Identification of diarrhoeal pathogenesis and medicinal plants used as therapeutic Agents 10.2. Antimicrobial evaluation of the extracts against infectious pathogens 10.3. Antioxidant evaluation of the extracts 10.4. Anti-inflammatory potential of the extracts 10.5. Toxicity risk of the extracts 10.6 Motility modulatory effects of Bauhinia galpinii and Combretum vendae 10.7. Isolation and characterisation of bioactive compounds CHAPTER 11 References

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Abstract Bauhinia galpiniiCombretum vendae

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Combretum vendae Bauhinia galpinii Bauhinia galpinii Combretum vendae

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List of Abbreviations

A B Bauhinia bowkeri Bauhinia galpinii Bauhinia petersiana Bauhinia variegata Bauhinia galpinii C Combretum bracteosum Combretum padoides Combretum vendae Combretum woodii Combretum vendae D Escherichia coli E Escherichia coli Escherichia coli Escherichia coli Escherichia coli Escherichia coli Euclea crispa Euclea natalensis

F Ficus cratestoma Ficus glumosa G H I Indigofera cylindrica L M Maytenus peduncularis Maytenus procumbens Maytenus senegalensis Maytenus undata N

O Ozoroa mucronata Ozoroa paniculosa

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P R S Schotia brachypetala Searsia leptodictya Searsia pendulina Searsia pentheri Syzygium paniculatum T U W

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List of Figures Chapter 2 Chapter 3 Chapter 4 S. aureus S. aureus E. faecalis E. coli E. faecalis C. neoformans C. neoformans A. fumigatus A. fumigatus C. albicans

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C. albicans Chapter 5 Chapter 6 Chapter 8 B. galpinii B. galpinii B. galpinii B. galpinii C. vendae C. vendae Chapter 9

Combretum vendae Bauhinia galpinii C. vendae B. galpinii

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List of Tables Chapter 2 E.coli Chapter 3 Chapter 4 Chapter 5

Chapter 6 Chapter 7

Chapter 9 C. vendae B. galpinii

List of Appendix

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