PROXIMATE AND PHYTOCHEMICAL ANALYSIS OF SOURSOP
ABSTRACT
Numerous bioactive compounds and phytochemicals have been reported to be present in Annona muricata (Soursop). Some of these chemical compounds have been linked to the ethnomedicinal properties of the plant and its antioxidant properties. The aim of this study was to assess the proximate composition and phytochemical constituents of A. muricata using standard biochemical procedures. The defatted Annona muricata crude methanolic extracts of the different parts of the plant were used for the estimation of proximate composition and phytochemical screening. The crude methanolic extracts of the different parts of the plant were also fractionated using solvent–solvent partitioning. Petroleum ether, chloroform, ethyl acetate, methanol, and methanol-water (90:10) were the solvents used for the fractionation. The leaf methanolic extract had a higher lipid content, whereas its chloroform fraction demonstrated a better ability to quench DPPH free radical. The root-bark methanol-water, leaf methanol, fruit pulp chloroform, and leaf petroleum ether fractions demonstrated potent ferric reducing properties. The leaf and stem-bark petroleum ether fractions demonstrated better hydroxyl-free radical scavenging abilities. The leaf and fruit pulp of Annona muricata have a very potent antioxidant ability compared to the other parts of the plant. This can be associated with the rich phytochemicals and other phytoconstituents like phenols, flavonoids, alkaloids, and essential lipids, etc. Significant correlations were observed between the antioxidant status and phytochemicals present. These results thus suggest that some of the reported ethnomedicinal properties of this plant could be due to its antioxidant potentials.
TABLE OF CONTENTS
ABSTRACT
CHAPTER ONE
1.1 Background of the Study
1.2 Problem Statement
1.3 Justification
1.4 Objectives
CHAPTER TWO
LITERATURE REVIEW
2.1 Introduction
2.2 Taxonomical Characterisation and Description Of Soursop
2.3 Types of Annona Genus Plants
2.4 Traditional Usages Of Annona Genus Plants
- Demand for Soursop
2.6 Health Beneficial Constituents Of Soursop
2.6.1 Antioxidant Activity (AOA)
CHAPTER THREE
MATERIALS AND METHODS
3.1 Preparation of Plant Material for Proximate And Phytochemical Analyses
3.2 Preparation of Plant Material for Phytochemical Analyses and in Vitro Antioxidant Assays
3.3 Proximate Composition
3.4 Phytochemical Screening
CHAPTER FOUR
RESULTS
4.1 Results of Proximate Analyses
4.2 Phytochemical Analysis of Fruit, Leaf, Stem-Bark, and Root-Bark of Annona Muricata
CHAPTER FIVE
5.0 Discussion
5.1 Conclusion
5.2 Recommendation
References
CHAPTER ONE
1.1 BACKGROUND OF THE STUDY
Edible wild indigenous plants become an alternative source of food with high potential of vitamins, minerals and others interesting elements particularly during seasonal food shortage (Umaru et al., 2007). Wild fruits are also known to have nutritional and medicinal properties that can be attributed to their antioxidant effects and they can be used to fortify staple foods particularly for malnourished children (Barminas, 1998). There is much evidence that the quality and composition of food may contribute to present and future health benefits of young children.
According to the World Health Organization, malnutrition is the cellular imbalance between the supply of nutrients and energy and the body’s demand for them to ensure growth, maintenance, and specific functions (Tierney et al., 2010). The term protein-energy malnutrition (PEM) applied to a group of related disorders that include marasmus, kwashiorkor, and intermediate states of marasmus-kwashiorkor (Tierney et al., 2010). The most common form of malnutrition in Africa is protein energy deficiency affecting over 100 million people, especially 30 to 50 million children under 5 years of age (Jildeh et al., 2010). Some legumes such as soybean, bean, and peanut, are important sources of protein and can therefore help to increase the protein intake of the diet of population. However, the low-income group, especially in rural areas, sometimes cannot afford these protein foods. Soursop (Annona muricata) belongs to the family Annonaceae, and it is wide spread in the tropics and frost–free subtropics of the world (Samson, 1980). The soursop plant is cultivated mainly in home gardens. The tree yields up to 10 tons/ha and each fruit weighs 0.5 to 2 kg (National Academy of Science, 1978). The fruit is compound in and covered with reticulated, leathery-appearing but tender, inedible bitter skin from which protrude few or many stubby, or more elongated and curved soft, pliable “spines”. The skin is dark-green in the immature fruit, becoming slightly yellowish-green before the mature fruit is soft to the touch. In aroma, the pulp is somewhat pineapple-like, but its musky, subacid to acid flavor is unique (Schultes and Raffauf, 1990).
It is indigenous to most of the warmest tropical areas in South and North America including Amazon, A. muricata has become naturalized in many countries, and now has a wide distribution throughout tropical and subtropical parts of the world. The fruit makes an excellent drink or ice cream after straining. Several studies have described the medicinal purposes of Annona muricata and have outlined the social history of the plants’ use (Ayensu, 1981). All parts of the A. muricata tree are used in natural medicine in the tropics including the bark, leaves, root and fruit-seeds. The crushed seeds are used as a vermifuge and anthelmintic against internal and external parasites and worms. The bark leaves and roots are considered
