ABSTRACT
Methanol and Aqueous extract of Sphenocentrum jollyanum roots (chewing stick) were screened for their antibacterial activity against E. coli, P. mirabilis, S. aureus and K. pneumoniae. Different concentrations were used (0.1, 0.2, 0.5 and 1mg/disc) to evaluate the roots extracts using disc diffusion and broth dilution method. The results showed that only methanol extract of Sphenocentrum jollyanum roots was effective against all the organisms tested. In disc diffusion method, there was a gradual increase in activity as the concentration increases from 0.1 – 1mg/disc. Similar pattern was observed with Broth dilution for MIC and MBCs determination using the same extracts in which four different concentrations, 100, 50, 25 and 12.5mg were used. The minimum inhibitory concentration (MIC) of the extract required to control the bacterial load was found to be 0.5mg for all the organisms tested, whilst the other two concentrations 12.5mg/ml and 25mg/ml were resisted by all the tested organisms. The minimum bactericidal concentration (MBC) was found to be negative in all the strains tested in this study probably due to the least concentrations used. For MBC the activity was dependent on the concentration used which is an important factor to obtain optimum antibacterial activity of extract used. In the present study the MIC value of the extract obtained in this study were higher than the MBC values (Table 4) suggesting that the methanol extract was bacteriostatic at lower concentration but bactericidal at higher concentration. Therefore these four strains used, E. coli showed the highest sensitivity, followed by P. mirabilis, and S. aureus, while K. pneumoniae exhibited the highest resistivity.
Keywords: Sphenocentrum jollyanum, antibacterial, Minimum inhibitory concentration (MIC), Minimum bactericidal concentration (MBC).
TABLE OF CONTENTS
Cover page……..………………………………………………………………………i
Fly leaf ...………………………………………………………………………….…..ii
Declaration…………………………………………………………………………….iii
Certification…………………………………………………………………………….iv
Acknowledgement………………………………………………………………….....v
Abstract……………………………………………………………………………….vi
Table of contents…………………………………………………………………….vii
List of Tables………………………………………………………………………….xi
List of Figures………………………………………………………………………...xii
CHAPTER ONE
1.0 Introduction……………………………………………………………………....1
1.1 Chewing stick (Sphenocentrum jollyanum root)………………………………..1
1.1.1 Ecology…………………………………………………………………………2
1.1.2. Phytochemical properties……………………………………………………..2
1.1.3. Scientific classification………………………………………………………..3
1.1.4 Uses of Sphenocentrum jollyanum ……………………………………………3
1.2 Justifications of the Study ………………………………………………………….4
1.3 Aim and Objectives of the Study………………………………………………..5
1.3.1 Aim of the Study………………………………………………………………5
1.3.2 Objectives of the Study………………………………………………………..5
CHAPTER TWO
2.0 Literature Review…………………………………………………………………6
2.1 Medicinal Plants ………………………………………………………………….6
2.2.0 Phytochemical composition of medicinal plants………………………………7
2.2.1 Phenolic compounds …………………………………………………………...7
2.2.2 Flavonoids ………………………………………………………………………8
2.2.3 Saponins …………………………………………………………………….......8
2.2.4 Quinones ……………………………………………………………………......9
2.2.5 Tannins ………………………………………………………………………….9
2.2.6 Alkaloids…………………………………………………………………..…….10
2.2.7 Essential (volatile) oils ………………………………………………………….10
2.2.8 Sulfur compounds ………………………………………………………………10
2.2.9 High concentration of chloride …………………………………………………10
2.3 Overview of the Antimicrobial Activity of Sphenocentrum jollyanum……………11-16
CHAPTER THREE
3.0 Collection and Identification of Plant Material……………………………...............17
3.1 Preparation of Plant Extract…………………………………………….....……..17
3.2 Extraction of plant material ……………….…………………………….………17
3.3 Clinical Bacterial Isolates……………………………………….………………..17
3.4 Gram staining procedure……………………………………………………………..18
3.5.0 Biochemical Test………………………………………………………………..19
3.5.1 Coagulase Test…………………………………………………………………..19
3.5.2 Catalase Test…………………………………………………………………….20
3.5.3 Indole Test………………………………………………………………………20
3.5.4 Citrate Test………………………………………………………………………21
3.5.5 Urease Test……………………………………………………………………...21
3.5.6 Kligler Iron Agar Test…………………………………………………………..22
3.5.7 Motility test…………………………………………………………………......23
3.6. Inoculum Standardization………………………………………………..……...23
3.7 Preparation of sensitivity discs and Bioassay procedure ……………..….…….23
3.8 Determination of MIC and MBC………………………………………………...24
3.9 Phytochemical screening…………………………………………………………25
3.9.1 Preparation of Dragendroff’s reagent………………………………………….25
3.9.2 Preparation of Meyer’s reagent………………………………………………...25
3.9.3 Test for alkaloid…………………………………………………………….…..25
3.9.4 Test for saponin………………………………………………………………...26
3.9.5 Test tannin……………………………….……………………………………...26
3.9.6 Test for flavonoid………………………………………………………………26
CHAPTER FOUR
4.0 Results…………………………………………………………………………27-35
CHAPTER FIVE
5.0 Discussion…………………………………………………………………….....36
5.1 Conclusion……………………………………………………………………….38
5.2 Recommendations …………………………………………………………………38
5.3 References……………………………………………………………………...40-45
