OPTIMIZATION OF GROWTH FACTORS OF Bacillus megaterium ISOLATED FROM A RHIZOSPHERIC SOIL OF TUMERIC PLANT

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