ABSTRACT
Helicobacterpylori infection, a highly prevalent pathogen, is a major cause of chronic gastritis and peptic ulcer and a risk factor for gastric malignancies. Antibiotics-based Helicobacterpylori eradication treatment is 90% effective. However, it is expensive and causes side effects and antibiotic resistance. The use of probiotics could present a low-cost, large-scale alternative solution to prevent or decrease Helicobacterpylori colonization. This study investigates the capacity of probiotics, isolated from local rice water, to inhibit Helicobacterpylori growth. The effect of probiotics on Helicobacterpylori growth and Helicobacter proliferation were examined in vitro of the isolates identified from this study, the probiotic LABB had the highest zone inhibition of 18mm against Helicobacter isolate Hp3 while LABD had the least inhibition zone of 2mm against Helicobacterpylori isolate Hp1. These results therefore, demonstrate that the intake of foods containing probiotics can inhibit Helicobacterpylori growth and is thus a promising treatment for patients with Helicobacterpylori infections.
TABLE OF CONTENTS
TITLE PAGE
CERTIFICATION
DEDICATION
ACKNOWLEDGEMENTS
ABSTRATCT
TABLE OF CONTENTS
LIST OF TABLES
CHAPTER ONE: INTRODUCTION
1.1 Aims and Study objectives
CHAPTER TWO: LITERATURE REVIEW
2.1 Genus description and phylogeny
2.1.1 Morphology and physiology of Helicobacter pylori
2.2 Virulence factors of Helicobacter pylori
2.2.1 Factors affecting colonization efficiency
2.2.2 Survival of Helicobacter pylori in human body
2.3 Peptic ulcer
2.3.1 Signs and symptoms of Helicobacter pylori infection (peptic ulcer)
2.3.2 Complications of peptic ulcer
2.4 Antimicrobial resistance of Helicobacterpylori
2.4.1 Transmission of Helicobacterpylori
2.4.2 Age of transmission
2.4.3 Route of transmission
2.4.4 Epidemiology of Helicobacterpylori
2.4.5 Epidemiology of Helicobacterpylori
2.4.5 Diagnosis of Helicobacter pylori infection
2.4.6 Treatment and prevention of Helicobacter pylori infection
2.5 Definition of probiotics
2.5.1 History of probiotics
2.5.2 Probiotic microorganisms
2.5.3 Effect of probiotics on Helicobacterpylori
2.5.4 Mechanism of action
CHAPTER THREE: MATERIALS AND METHODS
3.1 Materials used
3.2 Preparation of media and reagents
3.3 Sample collection
3.3.1 Source of pathogen
3.3.2 Isolation of probiotics from rice water
3.4 Purification and maintenance of cultures
3.5 Biochemical characterization and identification of isolates
3.7 In vitro study protocol
CHAPTER FOUR: RESULTS
4.1 Total HetertrophicBacterial Count
4.2 Macro-morphological characteristics of Helicobacter pylori isolates
4.3 Biochemical characterization and identification of Helicobacter pylori isolates
4.4 Biochemical characterization and identification of Lactobacilli isolates
4.5 Percentage occurrence of the bacterial isolates
4.6 Antibacterial activity of Lactobacilli against Helicobacterpylori
CHAPTER FIVE: DISCUSSION, CONCLUSION AND RECOMMENDATION
5.1 Discussion
5.2 Conclusion and Recommendation
REFERENCES
APPENDICES
CHAPTER ONE
INTRODUCTION
The genus Helicobacter is a Gram negative bacterium possessing a characteristic helical shape. They were initially considered to be members of the genus Campylobacter, but in 1989, Goodwin et al., published sufficient reasons to justify the new genus name Helicobacter (Goodwin et al., 1989). Boyanova (2011) and Yamoaka (2008) reported that Helicobacter has about 35 species. Some species have been found living in the lining of the upper gastrointestinal tract as well as the liver of mammals and some birds (Ryan and Ray 2004). The most widely known species of the genus is Helicobacter pylori, which infects up to 50 percent of the human population (Yamoaka 2008). Some strains of this bacterium are pathogenic to humans, as they are strongly associated with peptic ulcers, chronic gastritis, duodenitis and stomach cancer. These species are able to thrive the acidic mammalian stomach by producing large quantities of the enzyme urease, which locally raises the pH from about 2 to a more biocompatible range of 6 to 7. Bacteria belonging to this genus are usually susceptible to antibiotics such as penicillin. They are microaerophilic (optimal oxygen concentration between 5 and 14 percent) and are fast moving with their flagella (Rust et al., 2008). Helicobacter pylori is most likely transmitted from person to person (usually acquired in childhood).