Abstract

In vitro antibacterial activities of crude extract of Chromoleriaodorata and Emilia sonchifiliawere investigated against some humanpathogensincluding Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans using the agar well diffusion and broth dilution techniques. The ethanolic crude extract of both plants exhibited significant inhibitory action against all the isolates tested at an initial concentration of 200mg/ml except for Candida albicans. The zones of inhibition exhibited by the extract against the tested organisms ranged between 12.0 and 16.5mm for the ethanol extract of Chromoleriaodorata and 11.5 to 14.0mm for theEmilia sonchifilia extract, while the zones of inhibition exhibited by Gentamicin used as standard antibiotic control ranged between 19 and 21mm. There was a corresponding decrease in the zone of inhibition of the growth of the pathogens as the concentration of the extracts decreased. The minimum inhibitory concentrations exerted by the ethanol extract of Chromoleriaodorata against the bacterial isolates ranged between 12.5mg/ml and 25mg/ml while that of Emilia sonchifiliawas also between 12.5mg/ml and 25mg/ml. The percentage yields of phytochemical content of the leaves of the Chromolenaodorata and Emilia sonchifilia plants were as follows: alkaloids (1.63%, 2.09%), flavonoids (0.79%, 1.36%), saponins (6.05%, 0.91%), and tannins(0.74%, 0.82%) respectively. The result shows that the leaves of these plants have appreciable amount of these phytochemicals, hence their medicinal value. Chromolenaodoratahad the highest amount of saponin(6.05%) when compared with those of Emilia sonchifilia (0.91%). The significant antibacterial activities exhibited by the ethanol extracts of the plants confirmed the therapeutic potentials of these plants in treatment of various infections in herbal medicine. 

TABLE OF CONTENTS

Title page

Certification i

Dedication ii

Acknowledgement iii

List of tables iv

Abstract v

Chapter One

Introduction

Chapter Two

2.0 Literature Review 5

2.1 Historical Background on Medicinal Plant 5

2.2 Brief Overview of the Test Organisms 6

2.2.1 Staphylococcus aureus 6

2.2.2 Psedomonasaeruginosa 7

2.2.3 Candida albicans 7

2.3 Antimicrobial Resistance 8

2.4 Origin and Medicinal use of Emilia sonchifolia 9

2.5 Origin and medicinal uses of Chromolaenaodorata 11

2.6 Phytotherapy 13

2.7 Phytochemicals 13

2.7.1 Tannins 14

2.7.2 Alkaloids 15

2.7.3 Saponins 16

2.7.4 Flavonoids 16

2.7.5 Phenolic Compounds 17

Chapter Three

3.0 Materials and Methods 18

3.1 Materials 18

3.2 Methods 18

3.2.1 Preparation of plant extracts 18

3.2.2 Collection of the Pathogens 19

3.2.3 Preparation of Antibiotics Disc 19

3.3 Preparation of Stock Solution of Extract 19

3.4 Media Preparation 19

3.5 Antimicrobial Susceptibility Test 20

3.6 Determination of MIC and MBC 20

3.7 Quantitative Phytochemical Analysis 21

3.7.1 Determination of saponins 21

3.7.2 Determination of Tannins 22

3.7.3 Determination of Alkaloids 22

3.7.4 Determination of Flavonoids 23

3.7.5 Determination of Total Terpenoids 24

3.8 Statistical Analysis 24

Chapter Four

4.0 Results 25

Chapter Five

5.0 Discusiionand Conclusion

5.1 Discussion 30

5.2 Conclusion 31

5.3 Recommendation 32

References 33