ABSTRACT

Probiotics are the health promoting viable microorganisms that exhibit a beneficial effect on the health of human being by improving the intestinal microbial balance. Probiotic bacteria may produce various compounds, which are inhibitory to the growth of pathogen, which include organic acids (lactic and acetic acids), bacteriocins, and reuterin. In the present study a total of six(6) isolates of Lactic Acid Bacteria from fish feed were purified and screened for their antimicrobial activity against four human pathogenic organisms (Aspergillus niger, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa). The six(6) isolates were considered for their probiotic potential. The isolates were tolerant to 1, 3 and 6% NaCl, temperature of 25, 30, 37 and 400C. the isolates could able to survive at pH ranges 5-9. Some of the isolates were also resistant to antibiotics such as Amoxicillin, Ampicillin and Augumentin.  The selected lactic acid bacteria exhibited excellent probiotic characteristics and thus can be used as a potential source of probiotic. Study affirms their use in the development of new pharmaceutical preparations and functional foods as probiotics for the betterment of public health.

TABLE OF CONTENTS

Title Page i

Certification             ii

Dedication iii

Acknowledgement iv

Table of Contents v

List Of Tables vii

Abstract viii

CHAPTER ONE

1.0 Background of study 1

1.1 Aim of the study 2

1.2 Objectivs of the study 2

CHAPTER TWO

2.0 Literature Review 3

2.1 Lactic Acid Bacteria 3

2.2 Classification of lactic acid bacteria 3

2.3 Lactic acid bacteria as biopreservatives 4

2.4 Probiotics as immunity stimulators 6

2.5 Health benefits of probiotics 7

CHAPTER THREE

3.0 Materials and methods 12

3.1 Sample collection 12

3.2 Media preparation 12

3.3 Evaluation of probiotic potentials of isolated LAB cultures 12

3.3.1 NaCl tolerance 12

3.3.2 Temperature tolerance 12

3.3.3 pH tolerance 13

3.3.4 Antibiotic resistance 13

3.3.5 Screening of isolated bacteria cultures for antimicrobial activity 13

CHAPTER FOUR

4.0 Results 15

CHAPTER FIVE

5.0 Discussion and conclusion 21

5.1 Discussion 21

5.2 Conclusion 22

References