ABSTRACT

The present study was carried out to determine the prevalence of bacterial organisms isolated from biofilms of water system. Our results clearly demonstrated the overall prevalence raie of the microorganism was 100%. The frequency of occurrence of the bacterial isolates were; Staphylococcus 100%, Streptococcus 73.33%, Enterobacter 66.66%, E. coli 60% and Klebsiella 53.33%. The physiochemical analysis result obtained were all within the WHO standards for drinking water quality, the physiochemical parameters were within acceptable limits. The results were compared with WHO. The investigation shows that the boreholes water at male and female hostels met with WHO Standards for drinking water. Biofilms in drinking water distribution system could provide nutrients for microbial growth, bio systems and proliferation. It is necessary to treat water distribution plants and provide adequate public health education in order to safe guard human health and animal health especially in developing countries

TABLE OF CONTENTS

Title i

Certification ii

Dedication iii

Acknowledgement iv

Table of contents v

List of tables ix

List of figure x

Abstract xi

CHAPTER ONE: INTRODUCTION

1.1 Background Studies 2

1.2 Aim                                  3

1.3 Objectives

1.4 Problem Statement 3

CHAPTER TWO: LITERATURE REVIEW

2.1 Biofilm 4

2.2 Development of Biofilms 7

2.3 Environmental Factors Influencing Biofilm Development 8

2.3.1 Effect of pH 8

2.3.2 Rheological and Adhesive Properties of Biofilms 9

2.3.3 Effect of Temperature 9

2.4 Biofilms Formation 10

2.4.1 Factors Affecting Biofilms Formation 11

2.4.2 Substratum Effect 11

2.4.3 Conditioning Film 11

2.4.4 Hydrodynamics 12

2.4.5 Characteristics of Aqueous Medium 12

2.4.6 Horizontal Gene Transfer 12

2.4.7 Quorum Sensing 13

2.5 Biofilm Structure and Function 14

2.5.1 Extracellular Polymeric Substances 14

2.5.2 Protein 15

2.5.3 Interaction of Particles 16

2.6 Water 16

2.6.1 Sources of Water 17

2.6.1.1 Surface Water 17

2.6.1.2 Ground Water 17  

2.6.1.3 Sources of Water Contamination 17

2.7 Bacteria That Can Be Found In Water 18

2.7.1 Escherichia Coli 18

2.7.2 Staphylococcus aureus 19

2.7.3 Klebsiella Species 19

2.7.4 Streptococcus Species 20

2.7.5 Enterobacter Species 20

2.8 Physiochemical Quality of Water 21

2.8.1 Temperature 21

2.8.2 Total Dissolved Solids (TDS mg/c) 21

2.8.3 Hydrogen Ion Concentration 21

2.8.4 Alkalinity (Mg/V) 22

2.8.5 Total Hardness 22

2.8.6 Turbidity 22

2.8.7 Conductivity 22

2.8.8 Colour 23

2.8.9 Odour 23

2.9 Biofilms in Drinking Water Distribution Systems 23 

2.10 Effect of Long Storage of Water on Biofilm Formation 24

CHAPTER THREE: MATERIALS AND METHODS 

3.1 Study Area 25

3.2 Collection of Samples 25

3.3 Preparation of Culture Media 25

3.4 Bacteria Inoculation and Isolation 26

3.5 Isolation of Biofilm Producing Bacteria 26

3.6 Determination of Biofilm Formation of Isolates 27

3.7 Characterization and Identification of Organisms 27

3.8 Gram Stain 27

3.9 Biochemical Tests 28

3.9.1 Catalase Test 28

3.9.2 Coagulase Test 28

3.9.3 Citrate Utilization Test 29

3.9.4 Urease Test 29

3.9.5 Indole Test 29

3.9.6 Oxidase Test 30

3.9.7 Methyl Red Test 30

3.9.8 Motility Test 30

3.9.9 Sugar Fermentation Test 31

3.10 Methods for the Physico-Chemical Analysis of the Water 31

3.10.1 pH 31

3.10.2 Determination of Conductivity 31

3.10.3 Determination of Temperature 32

3.10.4 Determination of Turbidity 32

3.10.5 Determination of Dissolved Solids 32

3.10.6 Determination of Total Suspended Solids (TSS). 32

3.10.7 Determination of Chloride 33

3.10.8 Determination Dissolved Oxygen 33

3.10.9 Determination of Chemical Oxygen Demand 33

3.10.10 Determination of Nitrate 33

3.10.11 Determination of Phosphate 34

3.10.12 Determination of Sulphate 34

CHAPTER FOUR: RESULTS

4.0 Results 35

CHAPTER FIVE: DISCUSSION, CONCLUSION AND RECOMMENDATION 

5.1 Discussion 42

5.2 Conclusion 43

5.3 Recommendation 44

REFERENCES 45