<i>In vivo</i> anti-malarial activity of hydroalcoholic extracts from <i>Asparagus africanus</i> Lam. in mice infected with <i>Plasmodium berghei</i>

Abstract

Background: Malaria is a major public health problem in the world in general and developing countries in particular, causing an estimated 1-2 million deaths per year, an annual incidence of 300-500 million clinical cases and more than 2 billion people are at risk of infection from it. But it is also becoming more difficult to treat malaria due to the increasing drug resistance. Therefore, the need for alternative drugs is acute. Objective: This study aims at investigating the in vivo antiplasmodial activity of extracts of the roots and area parts from traditionally used medicinal plant, named Asparagus africanus (Liliaceae). Methods: A rodent malaria parasite, Plasmodium berghei, which was maintained at the Ethiopian Health and Nutrition Research Institute (EHNRI) laboratory, was inoculated into Swiss albino mice. The mice were infected with 1x10 7 parasites intraperitoneally. The extracts were administered by an intra gastric tube daily for four days starting from the day of parasite inoculation. The control groups received the same amount of solvent (vehicle) used to suspend each dose of the herbal drug. Chloroquine was used as a standard drug, and was administered through the same route. Results: Extracts from the roots and aerial parts of A.africanus were observed to inhibit Plasomodium berghei parasitaemia in the Swiss albino mice by 46.1% and 40.7% respectively. Conclusion: The study could partly confirm the claim in Ethiopian traditional medicine that the plant has therapeutic values in human malaria. There is, thus, the need to initiate further in-depth investigation by using different experimental models.

In vivo Antimalarial Evaluation of Embelin and its Semi-Synthetic Aromatic Amine Derivatives

“…C NMR data indicated that the reaction took place at C-5 position, not at the C-2 position of embelin (1) and this might be due to steric factor that is apparent in the latter. Further confirmation of the reaction site was obtained from 13 C NMR data, where +8.06 ppm upfield shift of C-6 in 2 (d 94.15) was observed compared to that of the same carbon in 1 (d 102.21) due to high electron donating nature of the amine group. Thus, compound 2 was finally characterized as 5-(p-tolylamino)-2-hydroxy-3-undecyl-cyclohexa-2,5-diene-1,4-dione as indicated below.…”

“…The 13 C NMR spectrum of compound 1 revealed signals corresponding to 13 carbon atoms only, which does not fit with the number of carbons proposed in the molecular formula above. This is because oxygen bearing ring carbons of 2, 5-dihydroxy-3-alkyl-1,4-benzoquinones do not appear in the 13 C NMR spectrum because of fluxional effect caused by intra-molecular hydrogen bonding. This effect leads to long spin relaxation time which in turn leads to the saturation of oxygen-carbon signals as it was also indicated by Mahendran et al 15 Hence, compound 1 was unequivocally identified as the known compound embelin (1) In an attempt to improve the antimalarial activity of embelin (1), its aromatic amino derivatives (2-4) were semi-synthesized (Scheme 1) by using a one-step condensation reaction of embelin (1) with p-toluidine (5), o-toluidine (6) and aniline (7), respectively, and tested against mice infected with P. berghei parasites.…”

“…NMR spectra ( using deuterated chloroform. A region from 0 to 12 ppm for 1 H and 0 to 205 ppm for 13 C was employed for scanning. Signals were referred to an internal standard tetra methylsilane (TMS …”

“…On the fifth day (D 4 ) thin blood smears were prepared fixed in MeOH and stained with 10 % Geimsa solution to be examined under the microscope with an oil immersion objective of 100x magnification power to evaluate percent suppression. [13][14] Percentage growth inhibition of the parasites was calculated by the following formula:…”

Formulation development and evaluation of the anti-malaria properties of sustained release artesunate-loaded solid lipid microparticles based on phytolipids

“…and Scientific Instrument). This was done every 24 h before each daily drug administration starting from the day prior to drug administration (Dikasso et al, 2006).…”