ROLES OF PHYTOCHEMICALS IN HEALTH ENHANCEMENT
TABLE OF CONTENTS
Title Page – – – – – – –
Certification – – – – – – –
Dedication – – – – – – –
Acknowledgements – – – – –
Table of Contents – – – – – –
CHAPTER ONE
1.0 Introduction – – – – – – –
CHAPTER TWO
2.1 Definition of Phytochemicals – – – –
2.2 History of the Use of Phytochemicals – – –
2.3 Effect of food processing on phytochemicals – –
2.4 Biological Activities of Phytochemicals – –
2.5 Classification of Phytochemicals – – – –
CHAPTER THREE
3.0 The Roles of phytochemicals in Health Enhancement
3.1 Flavonoid – – – – – – –
3.2 Alkaloids – – – – – – –
3.3 Terpenes – – – – – – –
3.4 Saponins – – – – – – –
3.5 Phenolic acid – – – – – –
3.6 Tannin – – – – – – –
3.7 Arthocyanidius – – – – – –
3.8 Carotenoids – – – – – – –
3.9 Glucosinolates – – – – –
CHAPTER FOUR
4.0 SUMMARY AND RECOMMENDATION
4.1 Summary – – – – – – –
4.2 Recommendation – – – – – –
References
CHAPTER ONE
1.0 INTRODUCTION
Phytochemicals (from the Greek word phyto, meaning plant) are biologically active, naturally occurring chemical compounds found in plants, which provide health benefits for humans further than those attributed to macronutrients and micronutrients (Hasler, 1999). They protect plants from disease and damage and contribute to the plant’s color, aroma and flavor. In general, the plant chemicals that protect plant cells from environmental hazards such as pollution, stress, drought, UV exposure and pathogenic attack are called as phytochemicals (Gibson, 1998). Recently, it is clearly known that they have roles in the protection of human health, when their dietary intake is significant. More than 4,000 phytochemicals have been cataloged and are classified by protective function, physical characteristics and chemical characteristics and about 150 phytochemicals have been studied in wide-ranging dietary phytochemicals are found in fruits, vegetables, legumes, whole grains, nuts, seeds, fungi, herbs and spices. Broccoli, cabbage, carrots, onions, garlic, whole wheat bread, tomatoes, grapes, cherries, strawberries, raspberries, beans, legumes, and soy foods are common sources (Moorachian, 2000). Phytochemicals accumulate in different parts of the plants, such as in the roots, stems, leaves, flowers, fruits or seeds. Many phytochemicals, particularly the pigment molecules, are often concentrated in the outer layers of the various plant tissues. Levels vary from plant to plant depending upon the variety, processing, cooking and growing conditions (Yong, 1999).
Phytochemicals are also available in supplementary forms, but evidence is lacking that they provide the same health benefits as dietary phytochemicals. These compounds are known as secondary plant metabolites and have biological properties such as antioxidant activity, antimicrobial effect, modulation of detoxification enzymes, stimulation of the immune system, decrease of platelet aggregation and modulation of hormone metabolism and anticancer property. There are more than thousand known and many unknown phytochemicals. It is well-known that plants produce these chemicals to protect themselves, but recent researches demonstrate that many phytochemicals can also protect human against diseases (Narasinga, 2003).
Phytochemicals are not essential nutrients and are not required by the human body for sustaining life, but have important properties to prevent or to fight some common diseases. Many of these benefits suggest a possible role for phytochemicals in the prevention and treatment of disease, because of this property; many researchers have been performed to reveal the beneficial health effects of phytochemicals. The purpose of the present review is to provide an overview of the extremely diverse phytochemicals presents in medicinal plants.