Physiochemical Properties And Fatty Acid Composition Of African Star Apple Seed Oil

Introduction

The genus Chrysophyllum is a family of trees and shrubs well marked by latex, and alternate, simple, usually exstipulate leaves; stipules when present fall easily. The genus Chrysophyllum is derived from Greek, meaning “golden-leaf” because of the colour of the hairs of some species. In a few others, however, the colour of the hairs is silverywhite. The genus Chrysophyllum, Linn. is represented in most parts of Africa by thirteen species, eight of which (including C. albidum) occur in Nigeria. However, while Keayet al., (1964) and Keay (1989) reported only seven species for Nigeria, Hutchinson and Dalziel (1963) reported eight species including C. Prunifolium. All the Nigerian species of Chrysophyllum are tall or medium-sized trees except C. welwitschii which is a woody climbing shrub. On the other hand, Hawthorne (1995) reported only six species for Nigeria (Bada, 1997). The mature tree of Chrysophyllumalbidum G. Don has been variously described by several authors ( Aubreville, 1963; Hutchinson and Dalziel, 1963; Keayet al., 1964, Keay, 1989; Okafor, 1981).

Keay (1989) gave a very good account of the species of the genus that occur in Nigeria:

Chrysophyllumpentagonocarpum (A forest tree which grows up to 45 m high), Chrysophyllumpruniforme (A forest species closely related to C. pentagonocarpum), Chrysophyllumgiganteum (A forest tree, to 30 m high), Chrysophyllumsubnudum (An under storey tree in forest), Chrysophyllumperpulchrum (A forest tree, to 30 m high), Chrysophyllumdelevoyi (A species very closely related to C. albidum and may be no more than a variety of it. It was later cited in Nigeria as a synonym of C.albidum (Abbiw, 1990)), Chrysophyllumalbidum G. Don, Chrysophyllumalbidumis a closed forest tree species often planted in villages

Statement of Problem

An investigation on the antioxidant and food value of Chrysophyllumalbidumshowed the plant contains some phenol, flavonoid, anthocyanin, and proanthocyanidin and also a high antioxidant value [9]. Generally, the roots, barks, and leaves of Chrysophyllumalbidumare widely used as an application to sprains, bruises, and wounds in southern Nigeria [10]. The seeds and roots extracts of Chrysophyllumalbidumare used to arrest bleeding from fresh wounds and to inhibit microbial growth of known wound contaminants and also enhance the wound healing process [11]. The oil of Chrysophyllumalbidumhas been extracted from the corresponding seeds in a soxhlet extractor with hexane (boiling point range: 55∘C-65∘C) and analyzed for moisture content, pH, specific gravity, saponification value, refractive index, peroxide value, acid number, free fatty acid, and iodine value by [12]. Their results showed that the oil yield was of 21.57% and acid values were of 2.87. Similarly, [13] investigated into the extraction and characterisation of the seed oil. Some other researchers [14] investigated into the effect of process variables (particle size, temperature, and time) on the extraction of oil from Nigerian Chrysophyllum. Albidumto determine the optimum conditions for the extraction of the oil and also to characterize the oil extracted and determine its physicochemical properties. Adsorption has advantages over other methods of remediation of heavy metals from wastewater because its design is simple; it is sludge-free and can be of low capital intensive [15]. The most widely used adsorbent is activated carbon [16]. Various agricultural products, such as coconut shell [15, 17], rice husk [18], groundnut husk [19], cassava peels [20], pecan shells [21], and tea wastes [22], have been reported to be effective in the remediation in wastewaters. The seeds of Chrysophyllumalbidumhave been used in the adsorption of lead Pb from industrial wastewater by some researchers [23] where the effects of pH, contact time, and adsorbent mass were monitored. Steam-activated carbon prepared from Chrysophyllumalbidumseed shell for the adsorption of Cadmium in wastewater (kinetics, equilibrium, and thermodynamic studies) was also investigated by [24] and was observed to be a potential sequester of Cadmium in wastewater. Studies were conducted by [25] on the effect of pH on the sorption of cadmium (ll), nickel (II), lead (II), and chromium (VI) from aqueous solutions by African white star apple (Chrysophyllumalbidum) shell and realised the process is highly pH-dependent. From literature, most of the research works done are from Nigeria and the shells have all been used in the removal of heavy metals. The aim of this research paper is to extract and characterise oil from Chrysophyllumalbidumfruit seed from Nigeria and use the seed shell as an adsorbent in the removal of methyl orange (dye) from aqueous solutions.

Aim of Study

To evaluate the phytochemical constituents and anti-bacterial of oil extracts of African star apple.

Objectives

1. To obtain the methanol, ethyl acetate, n- hexane and aqueous extracts of leaf of African star apple.
2. To determine qualitatively and quantitatively secondary metabolites present in the methanol, ethyl acetate, n- hexane and aqueous extracts of leaf of African star apples.
3. To assess the anti-bacterial activities of the aqueous, methanol, ethyl acetate and nhexane extracts of single and combined leaf of E. heterophyllaand M. villosuson some selected microorganisms.
4. To determine the Minimum Inhibitory Concentration (MIC) and Minimum Antibacterial Concentration (MFC) of aqueous, methanol, ethyl acetate and n-hexane extracts of single and combined plants.

Significance of the Study

The oil extracts of African star apple have been reported in the treatment of various ailments such as ulcer, cancer, skin diseases e.t.c. It is therefore important to scientifically investigate these plant parts to ascertain their therapeutic potentials.

Determination of their chemical composition as well as antimicrobial efficacy against specific pathogens is important in the recognition of this plant as a potent commercial medicinal plant. Tests can determine its efficacy against a pathogen and thus, establish the minimal dosage required for the treatment of ailments.