USING BIOCONTROL AGENTS TO CONTROL SALMONELLA SPECIES IN DAIRY PRODUCTS

ABSTRACT

Essential oil produced from turmeric and  Bacteriocin produced from Lactobacillus plantarum  were used to control Salmonella species found in dairy products. Six dairy products inculding  milk powdered,cheese,icecream,yoghourt, tin milk, fresh milk were screenced for Salmonella species, only three isolates were identified which inculde Salmonella typhi, Salmonella  enteric, Salmonella chloeraceau. Results showed the presene of  Salmonella species  in three  products yoghourt, fresh milk and milk powdered. Lactobacillus was  isolated from “ogi”(fermented maize starch) and it’s yield  of bacteriocin was 0.36% while essential oil yield from turmeric was  4.94%. The highest zone of inhibition was 24.33mm were recorded for bacteriocin activity aganist Salmonella species while the highest zone of inhibition for essential oil  showed antibacteria activity with  zone of inhibition in diameter of 14.33mm aganist the isolates .The test of biocontrol agents more also are found to be active  at low concentraction of 15mg/ml and 21mg/ml for bacteriocin and essential respectively. Comparatively the bacteriocin extract was found to have higher activity than the essential oil extracts and should be incoperated in strater culture in production of dairy products.

TABLE OF CONTENTS

Title page ﾿ i

Certification ﾿ ii

Acknowledgments ﾿ iii

Dedication ﾿ iv

Table of Contents ﾿ v

List of tables ﾿           vi ﾿

Abstract ﾿ vii

CHAPTER ONE

1.0 ﾿ Introduction

1.1        Introduction ﾿ 1

1.2 ﾿ Aim and Objectives ﾿ 2

CHAPTER TWO

2.0 ﾿ Literatue Review ﾿ 4

2.1 ﾿ Latic acid bacteria ﾿ 4

2.2 ﾿ Latic acid bacteria and bacteriocin ﾿ 6

2.3 ﾿ Bacteriocin ﾿ 7

2.4. ﾿ Classification of bacteriocin ﾿ 8

2.4.1 ﾿ Class 1 (Lantibiotics) ﾿ 8

2.4.2 ﾿ Class 11 (Small heat stable peptides) ﾿ 9

2.4.3 ﾿ Class 111(Large heat labile bacteria) ﾿ 9

2.4.4 ﾿ Class iv ﾿ 9

2.5.0 ﾿ Essential oil from turmeric ﾿ 10

2.5.1 ﾿ Scientific classification of turmeric ﾿ 10

2.5.2 ﾿ origin and  uses of turmeric ﾿ 11

CHAPTER THREE

3.0 ﾿ Materials And Methods ﾿ 15

3.1 ﾿ Materials ﾿ 15

3.2 ﾿ Methods ﾿ 15

3.2.1 ﾿ Sample Collection ﾿ 15

3.2.2 ﾿ Media Prearation ﾿ 15

3.3.0 ﾿ Isolation Of Salmonella From Dairy Products Determination of Micriobiral 

Load (cfu/g) ﾿ 15

3.3.1 ﾿ Confirmation of  Salmonella ﾿ 16

3.3.2 ﾿ Microscopic Examination/Gram Staining ﾿ 17

3.4.0 ﾿ Sources of Lactic Acid Bacteria ﾿ 17

3.5.0 ﾿ Biochemical  Tests ﾿ 18

3.5.1 ﾿ Indole Test ﾿ 18

3.5.2 ﾿ Cirtrate Utilization Test ﾿ 18

3.5.3 ﾿ Nitrate Reduction Test ﾿ 18

3.5.4    Catalase Test ﾿ 19

3.5.5   Cogulase Test ﾿ 19

3.5.6 ﾿ Oxidase Test ﾿ 19

3.5.7 ﾿ Sugar Fermentaion Tests ﾿ 19

3.7.0 ﾿ occurance  of Salmonella  in  Dairy Products ﾿ 20

3.8.0 ﾿ Extracton Of Biocontorl Extracts (Bacteriocin From Lactobacillus plantarum  and Essental Oil From Turmeric/Determination Yield

3.8.1 ﾿ Extracion of Essential Oil from Turmeric/Determination Yield ﾿ 20

3.8.2 ﾿ Extraction of  Bacteriocin /Detremination Yield ﾿ 21

3.9 ﾿ Antibacterial Activity Test ﾿ 22

3.10 ﾿ Antibiotics Senstivity Test ﾿ 23

3.11   Minimum  Inhibtion Concentraction (MIC) ﾿ 23

3.12 ﾿ Statistical Method ﾿ 23

CHAPTER FOUR

4.0 ﾿ Results ﾿ 24

CHAPTER FIVE

5.0 ﾿ Discussion, Conclusion And Recommendation ﾿ 29

5.1 ﾿ Discussion ﾿ 29

5.2. ﾿ Conclusion ﾿ 30

5.3 ﾿ Recommendation ﾿ 31

References                                                                                                               32

Appendix

List of Tables

Tables                                                     Title ﾿ Pages

1. ﾿           Occurance of Salmonella Species in Dairy Products ﾿                                    25

      2. ﾿             Precentage Yield Of Esseential oil And Baceteriocin ﾿ 26

       3.             Zone of Inhibition of Bacteriocin and Essential Oil Aganist ﾿ 27

Salomonella Species in Diameter (mm) ﾿  

      4.              Minimum Inhibition  Concentration of Essential Oil and ﾿ 28

Bacteriocin of  Salmonella Species. ﾿