MICROBIOLOGICAL ASSESSMENT OF INDOOR AND OUTDOOR AIR OF MICROBIOLOGY LABORATORY OF MOUAU

ABSTARCT

This study was designed to assess the microbiological quality of indoor and outdoor air of Microbiology laboratory of Michael Okpara University of Agriculture, Umudike. A total of six (6) air samples from the laboratory were collected and cultured on Nutrient Agar, MacConkey Agar, Nutrient Agar, Sabouraud Dextrose Agar and Salmonella-Shigella Agar using sedimentation techniques. From this study, a total of thirty (30) microbial species were isolated and identified as Bacillus sublitis, Staphylococcus aurues, Escherichia coli, Klebsilla spp, Streptococcus species, Aspergillus niger, Mucor alternaria and Aspergilus fumigates. This study showed that, Microbiology laboratory Umudike, Umuahia, Outdoor (afternoon) had the highest viable mean bacteria count (11.1x104), followed by Outdoor (morning) 10.5x104, Indoor (evening) 7.7x104, Outdoor (evening) 5.3x104, Indoor (afternoon) 5.2x104, while the least viable mean bacteria count was recorded on Indoor (morning) 3.8x104. The total viable mean fungal plate count showed that Outdoor air sample (afternoon) had the highest viable mean fungi count (13.2 x104), while Indoor (afternoon) air sample had the least viable fungi count (2.3 x104). The contamination rate and percentage distribution accessed on the Indoor laboratory Air samples in Microbiology laboratory revealed that, among the indoor air isolates Escherichia coli and Staphylococcus aureus are the most frequently occurring isolates, with a high percentage occurrence of 3(23.1%) each, while among the outdoor air isolates, Escherichia coli, Staphylococcus aureus and Bacillus spp and are the most frequently occurring isolates with a high percentage occurrence of 3(17.6%) each. However, there were slight variations in the fungi population, with Mucor alternaria 2(15.3%) being most predominant and occurring isolates, while from the outdoor laboratory air sample, Aspergillus fumagatus was the most predominant and occurring isolate at 2(11.8%). Therefore, the present work shows that the outdoor laboratory air is heavily contaminated with bacteria and fungi loads than the indoor air sample.

TABLE OF CONTENTS

Title Page ﾿   ﾿ i

Certification ﾿

Dedication ﾿ iv

Acknowledgements ﾿ v

Table of Contents ﾿ vi

List of Tables ﾿

Abstract ﾿ ix

CHAPTER ONE

1.0 ﾿ Introduction ﾿

1.2 ﾿ Aim and Objectives ﾿ 3

CHAPTER TWO

2.0 ﾿ Literature Review ﾿ 5

2.1 ﾿ Assessment of Airborne Bacteria and Fungi in an Indoor and Outdoor 

﾿ Environment ﾿

2.2 ﾿ Microbiological Indoor and Outdoor Air Quality of Selected Places in India ﾿ 7

2.3 ﾿ Microbiological Indoor and Outdoor Air Quality of Two Major 

﾿ Hospitals in Benin City, Nigeria ﾿ 9

2.4 ﾿ Microorganisms Associated with Airborne Contaminations ﾿ 10

2.4.1 ﾿ Bacteria Example ﾿ 11

2.4.2 ﾿ Fungi Example ﾿ 11

2.4.3 ﾿ Virus Example ﾿ 11

2.5 ﾿ Factors that Affect Indoor and Outdoor Air Quality ﾿ 11

2.5.1 ﾿ Temperature ﾿

2.5.2 ﾿ Relative Humidity ﾿ 12

2.5.3 ﾿ Microbes ﾿ 13

2.5.4 ﾿ Chemicals ﾿ 13

2.5.5 ﾿ Radiation ﾿ 13

2.5.6 ﾿ Oxygen, OAFs, and Ions ﾿ 14

CHAPTER THREE

3.0 ﾿ Materials and Methods ﾿ 16

3.1 ﾿ Study Area ﾿

3.2 ﾿ Materials ﾿ 16

3.3 ﾿ Media Preparation ﾿ 16

3.4 ﾿ Sterilization of Materials ﾿ 16

3.5 ﾿ Sampling Techniques ﾿ 16

3.6 ﾿ Identification of the Isolates ﾿ 17

3.7 ﾿ Gram Staining ﾿

3.8 ﾿ Biochemical Tests ﾿ 18

3.8.1 ﾿ Catalase Test ﾿

3.8.2 ﾿ Indole Test ﾿

3.8.3 ﾿ Citrate Utilization Test ﾿ 18

3.8.4 ﾿ Hydrogen Sulphide (H2S) Production Test ﾿ 19

3.8.5 ﾿ Starch Hydrolysis ﾿ 19

3.8.6 ﾿ Motility, Indole, Urease (MIU) ﾿ 19

3.8.7 ﾿ Coagulase Test ﾿ 20

3.8.8 ﾿ Oxidade

3.9 ﾿ Identification of Fungal Isolates ﾿ 20

3.9.1 ﾿ Wet Preparation ﾿ 20

3.9.2 ﾿ Colonial Morphology ﾿ 21

CHAPTER FOUR

4.0 ﾿ Results ﾿ 22

CHAPTER FIVE

5.0 ﾿ Discussion, Conclusion and Recommendations ﾿ 30

5.1 ﾿ Discussion ﾿ 30

5.2 ﾿ Conclusion ﾿

5.3 ﾿ Recommendations ﾿ 36

﾿ References 

LIST OF TABLES

TABLE ﾿ TITLE ﾿ PAGE NO

1 ﾿ Mean Microbial Counts on the Indoor and Outdoor Air in Microbiology Laboratory ﾿ 24

2 ﾿ Identification and characterization of Bacterial Isolates from Indoor and Outdoor Air in Microbiology Laboratory ﾿ 25

3 ﾿ Cultural Morphology and Microscopic Characteristics Fungal Isolates from Indoor and Outdoor Air Samples in Microbiology Laboratory ﾿ 26

4 ﾿ Distribution of Bacterial and Fungal Isolates from Indoor and Outdoor Air Samples in Microbiology Laboratory ﾿ 27

5a ﾿ Percentage Occurrence of the Various Isolates from Indoor Air Samples in Microbiology Laboratory ﾿ 28

5b ﾿ Percentage Occurrence of the Various Isolates from Outdoor Air Samples in Microbiology Laboratory ﾿ 29