In Vitro Antimicrobial Activities Of Hibiscus Sabdariffa And Moringa Oleifera On Tomato Spoilage Organisms

ABSTRACT

The invitro antimicrobial activities of Moringa oleifera and Hibiscus sabdariffa on tomato spoilage organisms was carried out. Spoiled tomato samples were purchased from four different markets in Umuahia Abia State and calyces of Hibiscus sabdariffa was purchased from the market, and also leaves of Moringa oleifera were gotten fresh from Moringa tree. The tomato samples were examined for the organisms which causes spoilage of tomato and the mean bacterial and fungal counts were gotten. The bacterial isolates were Escherichia coli and Bacillus sp. While the fungal isolate was Rhizopus sp. The colonial count of E. coli isolated from this study was in the range of 5.0 x 105 cfu/g to 1.5 x 106cfu/g while that of Bacillus ranged from 1.2 x03 to 1 5.0 x 104cfu/g. The mean fungal count was in the range of 4.7 x 105 to 2.8 x105. Moringa oliefera and Hibiscus sabdaffla leaf extract were shown to have some degree of antimicrobial properties on the tomato isolates by means of producing a zone of clearance around the growth of the organisms on nutrient plates. The aqueous extract of H. sabdariffa showed maximum activity against Bacillus species with a diameter zone of clearing of 20mm. The ethanol extract of both plants also recorded remarkable activity with zones of inhibition ranging from 6mm to 10mm for the Moringa extracts. The aqeous extract of Hibiscus sabdariffa had the lowest active concentration (MIC) against Rhizopus, E. coli, and Bacillus at 125mg/ml, 62.5mg/ml and 62.5mg/ml respectively. Plants have an almost limitless ability to synthesize aromatic substances. In many cases, these substances serve as plant defence mechanisms against predation by microorganisms.

TABLE OF CONTENTS

Title page ﾿ i

Certification ﾿ ii

Dedication ﾿ iii

Acknowledgement ﾿ iv

Table of Contents ﾿ v

List of Tables ﾿ ix

Abstract ﾿ x

CHAPTER ONE

INTRODUCTION

1.0 Introduction ﾿ 1

1.1 Spoilage microorganisms and their adverse effects on fruits and vegetables ﾿ 2

1.2 Adverse effects ﾿ 3

1.3 Aim and objectives ﾿ 4

CHAPTER TWO

LITERATURE REVIEW

2.0 Tomatoes ﾿ 5

2.1 Importance and uses of tomatoes ﾿ 5

2.2 Microorganisms associated with tomato spoilage and their effects ﾿ 6

2.3 Hibiscus sabdariffa (botanical and morphological description) ﾿ 7

2.4 Phytochemistry of Hibiscus sabdarriffa ﾿ 8

2.5 Biological and pharmacological activities of H. Sabdariffa ﾿ 9

2.5.1 Antimicrobial activity of H. Sabdariffa ﾿ 9

2.5.2 Antioxidant activity of H. Sabdariffa ﾿ 10

2.5.3 Cancer-preventive activity of H. Sabdariffa ﾿ 10

2.5.4 Uses of H. Sabdariffa ﾿ 10

2.6 Moringa  oleifera (botanical and morphological description) ﾿ 11

2.7 Phytochemistry of M. oleifera ﾿ 12

2.8 Biological and pharmacological activities of M.  oleifera ﾿ 13

 2.8.1 Antimicrobial Effects of Moringa  oleifera ﾿ 13

2.8.2 Antioxidant properties of Moringa  oleifera ﾿ 13

2.8.3 Anti-cancer properties of M. oleifera ﾿ 14

2.8.4 Uses of Moringa  oleifera ﾿ 14

CHAPTER THREE

Materials and Methods ﾿ 16

3.0 Sample collection ﾿ 16

3.1 Preparation of extracts ﾿ 16

3.2 Sterilization of materials ﾿ 16

3.3 Preparation of media ﾿ 17

3.4 Isolation and Enumeration of Microorganisms ﾿ 17

3.4.1 Isolation of bacteria ﾿ 17

3.4.2 Isolation of fungi ﾿ 18

3.5 Purification (subculture) of bacterial isolates ﾿ 18

3.6 Purification of fungal isolates ﾿ 18

3.7 Characterization and identification of isolates ﾿ 19

3.7.1 Gram staining ﾿ 19

3.7.2 Motility test ﾿ 20

3.8 Biochemical tests ﾿         ﾿ 21

3.8.1 Catalase test ﾿ 21

3.8.2 Coagulase test ﾿ 21

3.8.3 Oxidase test ﾿ 21

3.8.4 Urease test ﾿ 21

3.8.5 Indole test ﾿ 21

3.8.6 Methyl red- voges proskauer test ﾿ 21

3.8.7 Citrate utilizatrion test ﾿ 22

3.8.8 Sugar fermentation tests ﾿ 22

3.9 Determination of minimum inhibitory concentration ﾿ 22

3.9.1 Determination of bactericidal concentration (mbc) ﾿ 23

3.9.2 Antimicrobial susceptibility testing (invitro) ﾿ 23

CHAPTER FOUR

Results ﾿ 24

CHAPTER FIVE

Discussion, Conclusion and Recommendation ﾿ 35

5.0 Discussion ﾿ 35

5.1 Conclusion ﾿ 37

5.2 Recommendation ﾿ 37

References ﾿ 38