Chapter 1 : Introduction. Index. Abstract. Acknowledgements. Front.

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Front.

Acknowledgements.

Abstract.

Index.

Chapter 1 : Introduction.

1.1 : Natural products and plant defense.……….…………...page 9

1.2 : Natural products and drug discovery: ethno-botany and ethno-pharmacology. page 10

1.3 : Antimicrobial agents : natural, synthetic and natural scientifically researched. page 14

1.4 : Mode of action of antibiotics. ………....page 15

1.5 : Essential oils. ……….page 16

1.5.1 : Terpenes. ………..…….page 17

1.6 : The Lamiaceae Family. ………..……….page 21

1.7 : Salvia species. ………page 24

1.7.1 : Botanic information and distribution.……….………...…………. page 24

1.7.2 : Salvia officinalis. ………..………page 24

1.7.3 : Salvia somalensis. ………page 26

1.7.4 : Salvia dolomitica. ………...………..page 27

1.7.5 : Salvia patens. ………....page 28

1.8 : Ethnobotany and traditional uses. ………...………page 29

1.9 : Bioactivity studies carried out to date on Salvia spp.………..………page 30

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Chapter 2 : Materials and methods.

2.1 : Collection of the samples and preparation for hydro-distillation. ………..….page 39

2.2 : Hydro-distillation. ………page 39

2.2.1 : Material. ………...………page 39

2.2.2 : Procedure. ………..………..page 40

2.3 : Analysis of essential oils by GC-MS. ………...page 43

2.3.1 : Chemicals. ……….page 43

2.3.2 : GC and GC/MS analysis. ………..page 43

2.3.3 : Compounds identification. ………page 44

2.4 : Antibacterial activity via Disc Diffusion Assay. ……….………..page 44

2.4.1 : Preparation of the material. ……….…page 45

2.4.2 : Preparation of Isotonic saline solution : suitable for suspension of

microorganisms and as diluent of essential oil. ………...………page 47

2.4.3 : Preparation of Mueller-Hinton Agar (MHA) : suitable for culture of

Bacteria. ……….page 47

2.4.4 : Preparation of Turbidity standard – 0.5M McFarland. ………page 48

2.4.5 : Bacteria strains. ……….………..page 49

2.4.6 : Maintenance of bacterial cultures and isolation of colony for inoculation.

………...……page 51

2.4.7 : Preparation of E.O. dilutions. ………..page 52

2.4.8 : Pen-strep dilutions. ………...…………..page 57

2.4.9 : Negative control. ……….………page 57

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Chapter 3 : Results and discussion.

3.1 : Hydro-distillation. ………page 60

3.2 : Chromatograms and E.O. composition. ………page 61

3.2.1 : Essential Oils from S. officinalis. ………..…………..page 61

3.2.2 : Essential Oil from Salvia dolomitica. ………..………..page 63

3.2.3 : Essential Oil from Salvia patens. ……….…page 65

3.2.4 : Essential Oil from Salvia somalensis. ……….…page 67

3.2.5 : Discussion. ………page 69

3.3 : Antibacterial activity via Disc Diffusion Assay. ……….page 73

3.3.1 : Staphylococcus aureus. ………...………page 74

3.3.1.1 Discussion. ………..page 76

3.3.1.2 : Statistical analysis with SPSS. ………..page 83

3.3.2 : Staphylococcus epidermidis. ………..…….. page 84

3.3.2.1 : Discussion. ………page 87

3.3.2.2 : Statistical analysis with SPSS. ………...…page 94

3.3.3 : Enterococcus faecalis. ……….………page 96

3.3.3.1 : Discussion. ………page 98

3.3.3.2 : Statistical analysis with SPSS. ……….page 103

3.3.4 : Escherichia coli. ……….page 105

3.3.4.1 : Discussion. ………..page 107

3.3.4.2 : Statistical analysis with SPSS. ………...………..page 114

3.3.5 : Pseudomonas aeruginosa. ………page 116

3.3.5.1 : Discussion. ………..page 118

3.3.5.2 Statistical analysis with SPSS. ………...page 124

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Chapter 4 : Conclusions.

4.1 : GC-MS analysis and E.O. composition. ………..……….page 127

4.1.1 : Essential Oils from S. officinalis. ………..page 127

4.1.2 : Essential Oil from Salvia dolomitica. ………..page 127

4.1.3 : Essential Oil from Salvia patens. ………..……….page 128

4.1.4 : Essential Oil from Salvia somalensis. ………...………page 128

4.2 : Antibacterial activity via Disc Diffusion Assay. ……….page 129

4.3 : Suggestions for further works. ………..………..page 130

References.

Appendix.