Phytochemistry And Evaluation Of Some Plant Extracts On Streptococcus mutans AND Candida albicans

ABSTRACT 

The upsurge in the prevalence of side effects of many synthetic antimicrobial agents and incidence of multidrug resistant bacteria has spurred scientists on the research for plant based antimicrobial of therapeutic potentials. Azadirachta indica and Psidium guajava present such potential of high medicinal value. These plants are used in Nigeria traditionally as condiments and for treatment of various ailments such dental plague . The phytochemical composition of Azadirachta indica and Psidium guajava showed the presence of Tannin, Alkaloid, Saponin and Flavonoid. Aqueous and ethanol extracts of Azadirachta indica and Psidium guajava leaves were screened for antibacterial activity against Candida albican and Streptococcus mutans. Both extracts were found to exhibit selective inhibition against the isolates. The diameter zones of inhibition exhibited by the extracts were between 2 ± 0.01 – 10 ± 0.10 mm. The Minimum Inhibitory Concentration (MIC) determined by the agar diffusion method was between 10.00 and 2.50 mg/ml-1. Ethanol extracts showed more `inhibitory effect compared to the aqueous extracts. Results obtained show that the extracts of Azadirachta indica and Psidium guajava possess some level of antibacterial activities against Steptococcus mutans and Candida albicans.

TABLE OF CONTENTS

Title Page ﾿ i

Certification ﾿ ii

Dedication ﾿ iii

Acknowledgements ﾿ iv

Table of Contents ﾿ v

Lists of Tables ﾿ vii

Abstract ﾿ viii

CHAPTER ONE

1.0 ﾿ Introduction  ﾿ 1

1.1  ﾿ Aims and Objectives ﾿ 4

1.2  ﾿ Objectives ﾿ 4

CHAPTER TWO

2.0 ﾿ Literature Review ﾿ 5 ﾿

2.1 ﾿ Dogoyaro/Neem (Azadirachta indica) ﾿ 5

2.2 ﾿ Phytochemicals of Azadirachta indica ﾿ 8

2.3 ﾿ Antimicrobial Activity ﾿ 9

2.4 ﾿ Antibacterial and Anti-Fungal Activities ﾿ 10

2.5 ﾿ Guava (Psidium guajavaLinn.) ﾿ 10

2.6 ﾿ Streptococcus mutans ﾿ 14

2.7 ﾿ Candida albicans ﾿ 15

CHAPTER THREE

3.0      ﾿ Materials and Methods ﾿ 17

3.1 ﾿ Collection of Samples ﾿ 17

3.2  ﾿ Media Used ﾿ 17

3.3 ﾿ Sterilization ﾿ 17

3.4 ﾿ Collection of Test Organisms ﾿ 17

3.5 ﾿ Isolation and Identification of Bacteria and Fungi ﾿ 17

3.6 ﾿ Preparations of Plant Extracts ﾿ 18

3.7 ﾿ Phytochemical Analysis ﾿ 18

3.7.1 ﾿ Test for alkaloid ﾿ 18

3.7.2 ﾿ Test for flavonoid ﾿ 19

3.7.3 ﾿ Determination of saponins ﾿ 19

3.7.4 ﾿ Test for tannin ﾿ 20

3.8 ﾿ Antibiotic Sensitivity Testing ﾿ 20 ﾿

3.8.1 ﾿ Agar diffusion method ﾿ 20

3.9 ﾿ Determination of Minimum Inhibitory Concentration (MIC) ﾿ 20

CHAPTER FOUR

4.0  ﾿ Results ﾿ 22

CHAPTER FIVE 

5.0       Discussion Conclusion Recommendation ﾿ 27

5.1 ﾿ Discussion ﾿ 27

5.2 ﾿ Conclusion ﾿ 28

5.3 ﾿ Recommendation ﾿ 28

References ﾿ 29