ABSTRACT

Uvaria chamae and Eleusin indica exhibited antimicrobial activity against both the Gram positive and Gram negative test-organisms at 500mg/ml and 250mg/ml for methanolic extract except for P. aeruginosa ATCC27854 and E. faecalis ATCC7080 which had no inhibition. Aqueous and methanol extracts of Eleusin indica and Uvaria chamae had strong inhibition against Staphylococcus aureus ATCC25923, Escherichia coli ATCC25922 and Salmonella typhi at 500mg/ml. partial to no inhibition was observed in lower concentrations of 250mg/ml and 125mg/ml. The extracts had MIC values ranging from 250mg/ml-62.5mg/ml for Eleusine indica and Uvaria chamae and MBC values of 250mg/ml-125mg/ml. Strong inhibition was observed at MIC values of 125mg/ml except Escherichia coli ATCC25922 but at 62.5mg/ml. Only Staphylococcus aureus ATCC25923 and Escherichia coli ATCC25922 showed inhibition. Antimicrobial activity was also not observed from 62.5mg/ml, 31.2mg/ml, 15.6mg/ml and 7.81mg/ml for methanolic extracts of Uvaria chamae while antimicrobial activity was not observed from 62.5mg/ml - 7.81mg/ml for aqueous extracts of Uvaria chamae. Antimicrobial resistance was observed at 250mg/ml for aqueous and methanolic extracts of Uvaria chamae. The extract had no inhibition at 250mg/ml for methanolic and aqueous extracts of Eleusin indica while partial to no inhibition was observed at 125mg/ml and 62.5mg/ml for methanolic extract of Eleusin indica. Partial to no inhibition was also observed at 125mg/ml for aqueous extract of Eleusin indica. Antimicrobial activity was not observed for Aqueous extract of  Eleusin indica at 62.5mg/ml, 31.2mg/ml, 15.6mg/ml and 7.81mg/ml, while no antimicrobial activity was recorded for methanolic extract of  Eleusin indica from 31.2mg/ml, 15.6mg/ml and 7.81mg/ml. The phytochemical screening showed that the leaf extracts of Eleusin indica are rich in alkaloid (1.8%), saponin (1.71%) and terpenoid (1.67%) and Uvaria chamae are rich in alkaloid (1.8%), saponin (2.12%) and terpenoid (1.73%), while flavonoid (0.42%) and (0.8%) appears to be low in quantity for Eleusin indica and Uvaria chamae respectively. 

TABLE OF CONTENTS

Certification page i

Title page ii

Dedication iii

Acknowledgements iv

Table of Contents v

List of Tables vi

Abstract  vii

CHAPTER ONE

1.0 Introduction 1

1.1 Aims and objectives 4

Chapter two

2.0 Literature review 6

2.1 Antimicrobial properties of some medicinal plants 6

2.2 Antimicrobial activity mechanisms of natural products 10

2.3 Trends in medicinal plant use 14

2.3.1 Global herbal market 15

2.4 Conservation and sustainable use of medicinal plants 15

2.5 Major groups of antimicrobial secondary metabolites 16

CHAPTER THREE

3.0 Materials and methods 19

3.1 Collection of plant materials 19

3.2 Preparation of plant extract 19

3.2.1 Methanol extract preparation 19

3.3 Reactivation of stock culture of test organism/media used 19

3.3.1 Media preparation  20

3.3.2 Preparation of stock solution of extract 20

3.4 Collection of test organisms  20

3.5 Antimicrobial testing in the agar well diffusion method 20

3.6 Determination of minimum inhibitory concentration (MIC) 21

3.7 Determination of minimum bactericidal concentration (MBC) of the plant leaf 

extracts on test isolates 22

3.8 Phytochemical screening 22

CHAPTER FOUR

4.0 Results 24

CHAPTER FIVE

5.0 Discussion 32

5.1 Recommendation 34

5.2 Conclusion 34

References