CHAPTER ONE

1.0   INTRODUCTION TO MEDICINAL PLANTS……………………………..1

1.1   ALKALOIDS……………………………………………………………….2

1.2   POLYPHENOLS……………………………………………………………2

1.3   GLYCOSIDES………………………………………………………………3

1.4   TERPENES………………………………………………………………….4

1.5   AIMS AND OBJECTIVES OF STUDY…………………………………….6

CHAPTER TWO

2.0   LITERATURE REVIEW………………………………………………………7

2.1   PLANT METABOLISM AND PHYTOCHEMISTRY………………………7

2.2   ANTIOXIDANT ACTIVITY OF MEDICINAL PLANTS…………………..7

2.3   FORMATION OF OXIDANTS……………………………………………...8

2.4   EXOGENOUS SOURCES OF OXIDANTS………………………………..9

2.5   ENDOGENOUS SOURCES AND CHARACTERISTICS OF OXYGEN RADICALS…………………………………………………………………10

2.6   ANTIOXIDANT AND ITS MECHANISM………………………………..11

2.7   ANTIOXIDANT EXTRACTION PROCESSES…………………………..16

2.8   PHYTOCHEMICALS IN MANGIFERA INDICA………………………..20

CHAPTER THREE

3.0   MATERIALS AND METHODS…………………………………………….25

3.1   PLANT MATERIALS……………………………………………………..25

3.2   SOLVENTS USED………………………………………………………...25

3.3   EQUIPMENTS……………………………………………………………..25

3.4   PREPARATION OF PLANT EXTRACT………………………………….25

3.5   PHYTOCHEMICAL SCREENING………………………………………..26

3.6   COLUMN CHROMATOGRAPHY………………………………………..26

3.6.1    PREPARATION OF FINE SAND……………………………….26

3.6.2    PREPARATION OF PACKED COLUMN………………………27

3.7   PREPARATION OF THIN LAYER CHROMATOGRAPHY…………….27

3.7.1    PREPARATION AND ACTIVATION OF PLATE……………..27

3.7.2    SPOTTING AND DEVELOPMENT OF PLATE……………….27

3.7.3    VISUALIZATION OF SPOTS AND CHARACTERIZATION…….…………………………………..28

CHAPTER FOUR

4.0   RESULTS AND DISCUSSION……………………………………………..29

CHAPTER FIVE

5.0   CONCLUSION………………………………………………………………32

5.1 RECOMMENDATION………………………………………………………32

REFERENCES

LIST OF TABLES

Table 1: Widely used antioxidants and their applications.

Table 2: Results of Phytochemical screening

Table 3: Table showing the spots from the thin layer chromatography

Table 4: Table showing the solute front, solvent front and retention fraction values.

LIST OF FIGURES

Figure 1: Tannic acid structure

Figure 2: Structure of some terpenes

Figure 3: Structure of Mangiferin

Alkaloids, tannins, saponins, phenol, steroid, and flavonoids distribution in the barks of the medicinal plant Mangifera indica species native to Ago-Iwoye, Ogun state, south-western Nigeria were tested for. The medicinal plant was investigated for its phytochemical constituents. The phytochemicals were extracted from the barks and analysed by column and thin layer chromatography. Flavonoids, tannins, and alkaloids were not detected from the above listed phytochemicals in this study, in contrast phenols, saponins and steroids were present in the bark extracts.