COMPARATIVE STUDY OF DISINFECTANT EFFICIENCY OF ETHANOL, BLEACH AND PHENOLICS AGAINST Pseudomonas aeruginosa and Staphylococcus aureus

Ethanol, Bleach and Phenolics are three kinds of disinfectants which have been widely used in common laboratories.  In this study, a compared experiment on these three disinfectants efficiency was conducted against Staphylococcus aureus and Pseudomonas aeruginosa using agar hole diffusion method.  Different concentrations of bleach (1%, 2%, 3%, 4% and 5%) were used on both organisms.  Also (50%, 60%, 70%, 85% and 95%) of ethanol as well as (5%, 10%, 20%, 25%, and 30%) Phenolics were used. Diffrences in  concentrations tested was because, the original concentrations of the disinfectants differs. After 24 hours of incubation at 370C, the results showed that all the disinfectants inhibited the growth of the test organism in their concentrated forms.  The diameter of zone of inhibitions were measured around each well by using a ruler in millimeters, using different concentrations, their efficacies varied.  The results showed that 30% Phenolics had the best efficiency against both test organisms and 5% bleach had a better effect on Staphylococcus aureus than Pseudomonas aeruginosa, while ethanol showed least sensitivity. 70% concentration gave the highest effect on Staphylococcus aureus as compared with Pseudomonas aeruginosa.

Title Page

Certification

Dedication

Acknowledgements

Table of Contents

List of Tables

List of Figures

List of Plates

Abstract

CHAPTER ONE

1.0   Introduction

1.1   Aims and Objectives

CHAPTER TWO

2.0   Literature Review

2.1   History of Disinfectants

2.2   About Disinfectants

2.3   Sources of Contamination of Surfaces

2.4   Types of Disinfectants

2.5   Properties of A Disinfectant

2.6   General Features of Disinfectant

2.7   General Features of the Test Organisms

2.9   Mechanism of Actions of Disinfectants against Bacteria

2.10 Resistant Action of Bacteria

2.11 Advantages and Disadvantages of Disinfectants

2.12 General Guidelines in the Use of Disinfectants

CHAPTER THREE

3.0  Material and Method

3.1  Isolation of Bacteria  

3.2  Identification of Isolates

3.3  Preparation of Disinfectants

3.4  Antimicrobial Susceptibility Testing (Using Kirby Bauer diffusion Assay Well Method)

CHAPTER FOUR

4.0  RESULTS

CHAPTER FIVE

5.0  Discussion