MATERIALS AND METHODS

The plants were obtained from Pipeline Road, Tanke, llorin, Kwara State, Nigeria and were identified at the Herbarium Section of the Department of Plant Biology of the University of llorin, Ilorin, Kwara State, Nigeria as Acalypha hispida, Acalypha marginata and Acalypha racemosa. The leave samples were air dried for two weeks and ground into uniform powder using a blender. The aqueous extract of each sample was prepared by soaking 100 grams of dried powdered samples in 500ml of distilled water for 12 hours. The filtrate was used for phytochemical screening. The methanolic extracts of the leaves of each Acalypha specie was prepared using the same method for the aqueous extract, but methanol was the solvent used instead of distilled water. Proximate analysis were carried out on dried samples of leaves of the three Acalypha species.

Proximate analysis: Proximate analysis were carried out according to the procedure of Association of Official Analytical Chemist (A.O.A.C., 1990). This constitute the class of food present in samples such as carbohydrate,protein, fat, fibre, ash content and moisture content.

Phytochemical screening: Phytochemical screening procedures carried out were adapted from the previous work on plant analysis (Odebiyi and Sofowora, 1979). This analysis determines the biologically active non-nutritive compounds that contribute to the flavor, colour and other characteristics of plant parts. Examples of these are alkaloids, tannins, glycosides, hydroxyanthraquinones, phenolics steroids, saponins, flavonoids and phlobatannins.

Table 1:	Proximate composition of leaves of some Acalypha Species
Each value is a mean of four different determination ± Standard deviation.

Table 2:	Phytochemical constituents of aqueous extracts of leaves of Acalypha hispida, Acalypha racemosa and Acalypha marginata
+Detected. -Not Detected.

Table 3:	Phytochemical constituents of methanolic extracts of leaves of Acalypha hispida, Acalypha racemosa and Acalypha marginata
+Detected. -Not Detected.

RESULTS

The proximate composition of leaves of the three Acalypha Species are presented in Table 1. The result showed that leaves of all the three species of Acalypha contained a relatively high percentage of carbohydrate when compared with other compositions of each of the leaves. The phytochemicals tested for in the aqueous and methanolic extracts of the leaves and those detected for each Acalypha specie are summarized in Table 2 and Table 3 respectively. There was no difference in the phytochemicals detected or absent in both aqueous and methanolic leave extracts. Phenolics, flavonoids, hydroxyanthraquinones and saponins were detected in both extracts of leaves of all three species of Acalypha. Steroids and phlobatannins were detected in Acalypha hispida and Acalypha racemosa, while glycoside was detected only in Acalypha hispida.

DISCUSSION

The results obtained from proximate analysis of leaves of all three Acalypha species establishes that they can be ranked as carbohydrate rich leaves due to their relatively high carbohydrate content when compared with the other components of the leaves. The low moisture content of the leaves would hinder the growth of micro organisms and the storage life would be high (Adeyeye and Ayejuyo, 1994). The crude protein content of the leaves are: 13.78%, 16.19% and 18.15% for Acalypha hispida, Acalypha racemosa and Acalypha manginata respectively and they compare favourably with Heinsia crinita (14.7%), but they are relatively low when compared with Amaranthus caudatus (20.59%) (Etuk et al., 1998, Akindahunsi and Salawu, 2005), cassava leaves (Manihot utilisima), 24.88%, Piper Guineeses 29.78% and Talinum triangulare 31.00%. (Akindahunsi and Salawu, 2005). The values for ash content were 10.32%, 13.14% and 15.68% for the leaves of the three Acalypha species respectively. This requires investigation to ascertain the species of mineral elements as they are essential for tissue functioning and a necessity in daily requirement for human nutrition. The ash content of the leaves were lower than that of some leafy vegetables commonly consumed in Nigeria such as Talinum triangulare (20.05%). They are however higher than some other vegetables such as Occimum graticimum (8.00%) and Hibiscus esculentus (8.00%) (Akindahunsi and Salawu, 2005). The high ash content is a reflection of the mineral contents preserved in the food materials. The result therefore suggests a high deposit of mineral elements in the leaves (Antia et al., 2006). The value of the crude fat for the leaves of the three respective Acalypha species were moderate when compared to those of Talinum triangulare (5.90%), Baseila alba (8.71%), Amaranthus hybridus (4.80%), Calchorus africanum (4.20%) (Ifon and Bassir, 1979; Akindahunsi and Salawu, 2005). Dietary fats function in the increase of palatability of food by absorbing and retaining flavours (Antia et al., 2006). A diet providing 1-2% of its caloric of energy as fat is said to be sufficient to human beings as excess fat consumption is implicated in certain cardiovascular disorders such as atherosclerosis, cancer and aging (Antia et al., 2006).

The crude fibre content of 10.25%, 7.20% and 11.50% for a Acalypha hispada, Acalypha racemosa and Acalypha marginata respectively were high compared with Talinum triangulare (6.20%), Piper guineeses (6.40%), Corchorus olitorius (7.0%), bitter leaves (Vernonia amygdalina), 6.5% (Akindahunsi and Salawu, 2005), Non-starchy vegetables are the richest sources of dietary fibre (Agostoni et al., 1995) and are employed in the treatment of diseases such as obesity, diabetes, cancer and gastrointestinal disorders (Saldanha, 1995).

The phytochemical screening showed that all leaves contain phenolics, flavonoid, hydroxyanthraquinones and Saponins. These are known to exhibit medicinal activity as well as physiological activity (Sofowora, 1993). The absence of alkaloid in Acalypha racemosa in this study is inconsistent with the Opinion of Musa et al., 2000 who noted the presence of alkaloids in the leaves of Acalypha racemosa. Flavonoids have been shown to have antibacterial, anti-inflammatory, antiallergic, antimutagenic, antiviral, antineoplastic, anti-thrombotic and vasodilatory activity (Alan and Miller, 1996). The potent antioxidant activity of flavonoids their ability to scavenge hydroxyl radicals, superoxide anions and lipid peroxy radicals may be the most important function of flavonoids (Alan and Miller, 1996). Steroids and phlobatanins were detected in Acalypha hispida and Acalypha racemosa. Steroidal compounds are of importance and interest in pharmacy due to their relationship with such compounds as sex hormones (Okwu, 2001). The presence of other phytochemicals in aqueous extracts of leaves of leaves of Acalypha racemosa agrees with the results of Musa et al., 2000. Various Studies have shown that Saponins although non toxic can generate adverse physiological responses in animals that consumes them. They exhibit cytotoxic effect and growth inhibition against a variety of cell making them have anti-inflammatory and anticancer properties. They also show tumour inhibiting activity on animals (Akindahunsi and Salawu, 2005). From the above results, these leaves may serve as a constituent of human diet supplying the body with minerals, protein and energy. The presence of secondary plant products in the leaves of these three Acalypha species that are biologically important e.g. saponins and flavonoids contributes to its medicinal value thus they can be potential sources of useful drugs.