Antimicrobial, Antioxidant And Phytochemical Characteristics Of Coconut Oil

ABSTRACT

Due to the abundance of Cocos nucifera (coconut) in eastern part of Nigeria and considering its high consumption, this work was carried to determine the potential application of the oil by investigation of the phytochemical as well as the antioxidant compositions and antimicrobial properties of its extracted oil content. The oil was extracted using Soxhlet Apparatus. The phytochemical screening, antioxidant composition and determination of the antimicrobial properties were carried out. The standard method cocos nucifera oil has a low content of 21.6%. the phytochemical analysis of the oil revealed the presence of saponin 0.03mg/g, Alkaloids 0.11mg/g, Flavonoids 0.23 mg/g and absence of tannin and phenols. The antioxidant composition of it was not detected, the antimicrobial activity of coconut oil was tested on some test organisms which include Staphylococcus aureus, Escherichia coli and Candida albicans. The coconut oil yielded zones of inhibitions when checked against the organisms. Inhibition were observed on C. albicans with inhibition zone of 21.mm at 400µg concentration. E.coli and S. aureus were sensitive to Gentamicin antibiotic (control) While C. albicans was also sensitive to Griseofuloin (control) . The minimum inhibition  concentration of Cocos nucifera oil on E.coli was 2.0µg /ml, S. aureus 1.8µg/ml and on C. albicans 0.9 µg/ml. These results showed that the Cocos nucifera extracted oil contains an appreciable amount of phytochemicals. Therefore, justification of the use of the coconut oil for food, medicinal and cosmetic was expatiated. 

TABLE OF CONTENTS

Title page ﾿ i

Certification ﾿ ii

Dedication ﾿ iii

Acknowledgments ﾿ iv

Table of contents ﾿ v

List of Tables ﾿ vii

List of Figures ﾿ viii

Abstract ﾿ ix

CHAPTER ONE

INTRODUCTION

1.1 ﾿ Introduction ﾿ 1

1.2 ﾿ Aims and Objectives ﾿ 2

CHAPTER TWO

2.0 ﾿ Literature Review ﾿ 3

2.1 ﾿ Cocos Nucifera (Coconut) ﾿ 3

2.1.1 ﾿ Botanical Description ﾿ 3

2.1.2 ﾿ Historical Cultivation ﾿ 4

2.1.3 ﾿ Nutritional Values ﾿ 4

2.1.4 ﾿ Medicinal Values ﾿ 5

2.2 ﾿ Coconut Production in Nigeria ﾿ 7

2.3 ﾿ The Importance of Coconut in Nigeria ﾿ 7

2.3.1 ﾿ Plant ﾿ 7

2.3.2 ﾿ The Seed ﾿ 8

2.4 ﾿ Coconut Oil (Cocos nucifera oil) ﾿ 9

2.5 ﾿ Importance of Coconut as Oil Seed ﾿ 10

2.6 ﾿ Common Methods of Production of Coconut Oil ﾿ 10

2.6.1 ﾿ Milling by Traditional Methods ﾿ 10

2.6.2 ﾿ Copra Processing by Continuous Pressing ﾿ 11

2.6.3 ﾿ Wet Coconut Processing ﾿ 11

2.7 ﾿ Activities of Coconut Oil ﾿ 14

2.7.1 ﾿ Wound Healing Effect ﾿ 14

2.7.2 ﾿ Effect on Blood Sugar Control ﾿ 14

2.7.3 ﾿ Effect on Weight Loss ﾿ 14

2.7.4 ﾿ Immunomodulatory Effect ﾿ 14

2.7.5 ﾿ Edible Applications of Coconut Oil ﾿ 15

2.7.6 ﾿ Non-Edible Applications of Coconut Oil ﾿ 15

2.8 ﾿ Antimicrobial ﾿ 15

2.9 ﾿ Phytochemical ﾿ 18

2.10 ﾿ Antioxidants ﾿ 20

CHAPTER THREE

3.0 ﾿ Materials and Methods ﾿ 22

3.1.1 ﾿ Materials ﾿ 22

3.1.2 ﾿ Methods ﾿ 22

3.2 ﾿ Sample preparation ﾿ 22

3.2.1 ﾿ Media preparation ﾿ 22

3.2.3 ﾿ Test for sterility ﾿ 23

3.3 ﾿ Oil extraction and determination of yield ﾿ 23

3.4 ﾿ Phytochemical analysis ﾿ 23

3.4.1 ﾿ Test for tannins ﾿ 24

3.4.2 ﾿ Test for saponins ﾿ 24

3.4.3 ﾿ Test for Flavonoids ﾿ 24

3.4.4 ﾿ Test for Alkaloids ﾿ 25

3.5 ﾿ Quantitative phytochemical ﾿ 25

3.5.1 ﾿ Determination of tannins ﾿ 25

3.5.2 ﾿ Determination of Alkaloids ﾿ 27

3.5.3 ﾿ Determination of Flavonoids ﾿ 27

3.5.4 ﾿ Determination of saponin ﾿ 28

3.6 ﾿ Confirmation of microbial identity ﾿ 29

3.6.1 ﾿ Examination of Colony features ﾿ 30

3.6.2 ﾿ Microscopic features ﾿ 30

3.6.3 ﾿ Biochemical tests  ﾿ 30

3.6.3.1 ﾿ Catalase test ﾿ 30

3.6.3.2 ﾿ Oxidase test ﾿ 31

3.6.3.3 ﾿ Methyl red test ﾿ 31

3.6.3.4 ﾿ Voges Prokauer test ﾿ 31

3.6.4 ﾿ Sugar utilization test ﾿ 32

3.6.5 ﾿ Confirmation of identification ﾿ 32

3.6.6 ﾿ Antioxidant test ﾿ 33

3.7 ﾿ Antimicrobial activity test ﾿ 33

3.8 ﾿ Determination of minimum inhibitory concentration ﾿ 34

CHAPTER FOUR

4.1 ﾿ Result ﾿ 35

CHAPTER FIVE

5.1 ﾿ Discussion ﾿ 41

5.2 ﾿ Conclusion ﾿ 42

﾿ References ﾿

﾿ Appendices ﾿