The development of new drugs imperative is made by the problem of resistance of malarial parasites to available anti-malarial drugs .Discovery of new drugs is an alternative source with the use of natural plant products. The aim of this is to evaluate the anti-malarial activity of eluted fractions of Acacia nilotica root extract and also the phytochemicals responsible for this activity. The gradient of solvent mixture such as hexane, ethyl acetate and methanol were used in multiples of 100 ml where the extract was eluted successively and then each fractions were collected separately.4 main fractions namely F1, F2,F3 and F4 were produced which were selected on the basis of elutes that showed similar Rf values and thin chromatographic profiles.
Curative test was used to test those fractions separately for their anti-malarial activity. The packed cell volume (PCV), temperature and changes in body weight were also recorded. The results that were obtained were that fraction F1 at 50 and 100 mg/kg b/w produced significant and dose dependent reduction in the parasite count of Plasmodium berghei infected mice compared to that of the control used, there was a significant increment in the survival time of the mice compared to the control group and the malarial-induced anemia was made better by improving PCV by Fraction F1 in treated mice. The anti-malarial activity of A.nilotica’s extract was localized in F1 fraction of the extract. The F1 fraction was found to be rich in alkaloids and phenolics.
Curative test was used to test those fractions separately for their anti-malarial activity. The packed cell volume (PCV), temperature and changes in body weight were also recorded. The results that were obtained were that fraction F1 at 50 and 100 mg/kg b/w produced significant and dose dependent reduction in the parasite count of Plasmodium berghei infected mice compared to that of the control used, there was a significant increment in the survival time of the mice compared to the control group and the malarial-induced anemia was made better by improving PCV by Fraction F1 in treated mice. The anti-malarial activity of A.nilotica’s extract was localized in F1 fraction of the extract. The F1 fraction was found to be rich in alkaloids and phenolics.
INTRODUCTION
Malaria is a disease caused by a parasite which is preventable and curable but it causes thousands of infections and death hence it is also called tropical disease. The resistance of plasmodium parasite to the used anti-malarial drugs is the main challenge to the effective diagnosed malarial cases. Acacia nilotica which is also known as prickly tree or gum Arabic tree is a thorny, nitrogen fixing tree that grows to 14-17 cm and 2-3 diameter and is found in Egypt, South Africa, Kenya and Nigeria. It is used to treat cough, diarrhea, dysentery and leprosy and to cure impotence. The fruit is used to treat tuberculosis and powdered pods were used to treat diabetes mellitus. A.nilotica is rich in secondary metabolites such as tannins, terpenes, alkaloids, flavonoids and phenolic with known pharmacological properties.
MATERIALS AND METHODS
At first, the plant was collected, identified and authenticated. The Swiss albino mice (Mus musculus) were used for the experiment. The parasite used for this experiment was chloroquine sensitive rodent Plasmodium; P. berghei. Chloroquine phosphate and silica gel (70-230 mesh) were used as the main chemicals and other chemicals were prepared using distilled water. The root extract was air dried and pulverized using grinding machine and the powder was kept in air tight container in cool and dry place. Aqueous extraction was prepared by cold maceration process. Here, 400 g of powered root of A.nilotica was soaked in 1 L of distilled water and kept for 24 hours and was filtered. The filtrate was freeze-dried and this was carried out 3 times. Wet silica gel was loaded in column and the extract was kept in upper layer and was eluted in gradients of solvent mixture in multiples of 100 and the fractions were collected separately. Elutes having similar Rf values and thin chromatographic profiles were combined and 4 fractions were made which were tested for anti-malarial activity each using curative test.
The fractions were then subjected to phytochemical screening to determine the predominant secondary metabolite in each fraction. The parasite was then inoculated with 0.2 ml of infected blood in each mouse and then the mice were divided in 5 groups randomly with 6 mice/group. Group 1 was administered 10 mg/kg distilled water (negative control) , group2,3 and 4 were administered 25,50 and 100 mg/kg b/w of each fraction and group 5 was administered 5mg/kg b/w chloroquine (positive control). Same was done for F2, F3 and F4. In established malarial infection, the rane test was used to evaluate the schizonticidal activity of the fractions of A.nilotica and mean survival time was calculated and also percentage parasitemia was determined.
The fractions were then subjected to phytochemical screening to determine the predominant secondary metabolite in each fraction. The parasite was then inoculated with 0.2 ml of infected blood in each mouse and then the mice were divided in 5 groups randomly with 6 mice/group. Group 1 was administered 10 mg/kg distilled water (negative control) , group2,3 and 4 were administered 25,50 and 100 mg/kg b/w of each fraction and group 5 was administered 5mg/kg b/w chloroquine (positive control). Same was done for F2, F3 and F4. In established malarial infection, the rane test was used to evaluate the schizonticidal activity of the fractions of A.nilotica and mean survival time was calculated and also percentage parasitemia was determined.
PCV was then determined using a standard Micro-Hematocrit Reader, the body weight and temperatures were also monitored. The data so obtained was analyzed by Graphpad Prism version 5.02 and were expressed as means ±standard error mean (SEM).
DISCUSSION
Chloroquine was used in this research as a control group because Plasmodium parasite used for this is chloroquine-sensitive strain. This study was carried out in-vivo to see the involvement of immune system and effects of prodrug in the removal of infection in living host. Here, F1 and F2 caused dose-dependent and significant reduction in mean parasite count in doses 50 and 100mg/kg.
RESULT
From the experiment, it is seen that fraction F1 shows the anti-malarial activity which may be due to high proportion of alkaloid found in this fraction or due to synergistic effect of alkaloids with phenolic compound. This F1 fraction was able to improve PCV of treated mice either by prevention of malaria-induced hemolysis or by enhancing erythropoises. But this could not reverse the body temperature and weight loss associated with rodent malaria.
REFERENCE
Alli LA, Adesokan AA and Salawu AO (2016) Antimalarial Activity of Fractions of Aqueous Extract of Acacia nilotica root, Journal of Intercultural Ethnopharmacology, 5 (2); 180-185.