ABSTRACT

The antibiogram of some Gram negative pathogens (Escherichia coli, Salmonella and Shigella Species) to extract of Costus afar (Okpete) and Spondias mombin (Isikara) was evaluated. Bacteria Species were isolated from two plants (E. coli, Salmonella and Shigella). The Muller Hinton agar, Salmonella Shigella agar, Eosin Methylene Blue agar was used for the antimicrobial activity tests. The isolates were characterized culturally, phytochemically and biochemically. These bacteria Species were tested for their susceptibility in the different extracts (Okpete and Isikara). The phytochemical screening of the plant extracts, showed that the alkaloid was highly present and the cyanogenic glycoside was slightly present. The Antibiogram of the bacteria pathogen, Salmonella had the highest inhibition recorded with ethanol extract of Spondias mombin (17.67mm ± 0.58) while the least inhibition was with water extract of Costus afar (9.67mm ± 0.58). The minimum inhibition concentration showed values of 50mg/ml to 200mg/ml with variations among the extracts activity and ethanol extracts having the lowest concentration that affected inhibition. From the concentration of the relative potency of extracts, ethanol exhibited the highest potency of extracts while water exhibited the least potency of extracts. It is recommended that the potentials of these two plants in terms of health benefits should be harnessed.

TABLE OF CONTENTS

Cover page i

Certification ii

Dedication iii

Acknowledgements iv

Table of Contents v

List of Tables vii

Abstract x

CHAPTER ONE

Introduction 1

1.1 Background of the Study 1

1.2 Aim and Objectives 3

1.3 Objective of the Study 4

CHAPTER TWO

Review of Related Literature 5

2.1 Costus afer Ker Gawl (Zingiberaceae) 5

2.2 Spondias mombin (Anacardiaceae) 6

2.3 Antibacterial Activity of Medicinal Plants 7

2.4 Antibiogram of Bacteria Species 14

2.5 Chemical Composition of the Stem Extract of Costus afer (Bush Cane 17

2.6 Chemical Composition of the Leaf Extract of Spondias mombin (Ichakara) 21

2.7 Prevalence of Microorganism 23

2.8 Isolation of Microorganism 24

2.9 Antibiotics Susceptibility of Microbial Contaminants 26

CHAPTER THREE

Materials and Methods 29

3.1 Source of Materials 29

3.2 Sample and Media Preparations 29.

3.2.1 Preparation of Plant Samples 29

3.2.2 Media Preparation 29

3.2.3 Preparation of Plant Extracts 30

3.3 Confirmation of Gram Negative Pathogens 30

3.4 Qualitative Phytochemical Screenings 31

3.4.1 Test for Saponin 31

3.4.2 Test for Steroids  31

3.4.3 Test for Flavonoids 31

3.4.4 Test for Tannin 32

3.4.5 Test for Cyanogenic Glycoside (HCN) 32

3.4.6 Test for Alkaloids 32

3.4.7 Test for Starch 32

3.5 Antimicrobial Sensitivity Test 33

3.5.1 Determination of Relative Potency of Plant Extracts 33

3.6 Determinations of Minimum Inhibition Concentration (MIC) 34

3.7 Statistical Analysis 34

CHAPER FOUR

Results 35

CHAPTER FIVE

Discussion, Conclusion and Recommendation 43

5.1 Discussion 43

5.2 Conclusion 45

5.3 Recommendation 45

References 46

Appendix