ABSTRACT

Growth factors of Bacillus megaterium isolates from rhizospheric of turmeric plants were optimized. Five soil samples were obtained from rhizosphere of five different turmeric plants were screened for the presence of Bacillus megaterium and the isolates were culture under varying cultural conditions of pH, incubation temperature and time. Result showed a 60% occurrence of Bacillus megaterium in the turmeric rhizospheric soils and variation in the optimal of different cultural condition studied. An optimum culture pH of 6.0 was needed for each of the three Bacillus megaterium isolates while the highest bacterial load was obtained when incubated at 40oC for all the isolates. Similarly the optimum incubation time of 72hours was the same for each of the isolate. Peak population of Bacillus megaterium at the optimum conditions varied among the three Bacillus megaterium with values of 5.2 ×107, 5.77×107 and 6.01×107cfu/ml. At optimum temperature and corresponding biomasses of 32.56mg/ml to 35.64mg/ml. At the optimum pH (6.0) the bacterial loads were 7.77×107cfu/ml, 7.78 ×107cfu/ml and 7.87×107cfu/ml for the three isolates and with corresponding biomasses of 34.30mg/ml to 36.10mg/ml. incubation time optimum recorded peak loads of 6.77×107cfu/ml, 7.75×107cfu/ml and 8.03×107cfu/ml. incubation time was found to have the highest positive effect on the test isolates.

TABLE OF CONTENTS

Title page i

Certification ii

Dedication iii

Acknowledgments iv

Table of contents v

Lists of tables’ ix

List of figures x

Abstract xi

CHAPTER ONE

1.0 Introduction 1

1.1 Aims 3

1.2 Objectives 3

CHAPTER TW0

2.0 Literature review 5

2.1 Bacillus subtilis 5

2.2 Bacillus thurengeinsis 6

2.3 Bacillus cereus 6

2.3.1 History 7

2.3.2 Ecology 7

2.3.3 Identification through testing 8

2.4 Bacillus megaterium 9

2.4.1 History 9

2.4.2 Characteristics 10

2.4.3 Importance 10

2.4.4 Isolation 11

2.5 Tumeric 12

2.5.1 Dye 14

2.5.2 Indicator 15

2.5.3 Tradition use 15

CHAPTER THREE

3.0 Materials and methods 17

3.1 Materials 17

3.2 Methods 17

3.2.1 Samples and media operation 17

3.2.2 Processing of soil for bacterial isolation 17

3.2.3 Media preparation 18

3.3.0 Isolation of Bacillus from soil 18

3.3.1 Characterization of Bacillus isolates 19

3.3.1.1 Cultural morphology tests 19

3.3.1.2 Microscopy characteristics test 19

3.3.1.3 Biochemical tests 20

3.3.1.4 Sugar utilization 20

3.3.2 Identification of Bacillus isolates 20

3.4.0 Occurrence of Bacillus megaterium 21

3.5.0 Optimization of growth factors 21

3.5.1 Optimization of pH 21

3.5.2 Optimization of incubation temperature 22

3.5.3 Optimization of incubation time 23

3.6.0 Determination of growth performances 23

3.6.1 Determination of TVC (population) 24

3.6.2 Determination of biomass 24

CHAPTER FOUR

4.0 Results 26

CHAPTER FIVE

5.0 Discussion, Conclusion and Recommendation

5.1 Discussion 36

5.2 Conclusion 38

5.3 Recommendation 39

References 40

Appendix 45

LIST OF TABLES

TABLE                      TITLES                                               PAGES

1                                           Occurrences of Bacillus megaterium             29

LIST OF FIGURES

FIGURES                                                    TITLES                        PAGES

1 Effect of incubation temperature in the 

growth of Bacillus megaterium isolates 30

2 Effect of temperature in the biomass of 

Bacillus megaterium   31

3 Effect of PH in the growth of Bacillus megaterium

isolates      32

4 Effect of PH in the biomass of Bacillus megaterium

isolates  33

5 Effect of incubation time on the growth of Bacillus

megaterium isolates                                                                          34

6 Effect of incubation time on the biomass of Bacillus

megaterium isolates                                                                          35