In vivo antimalarial activity of crude extracts and solvent fractions of leaves of Strychnos mitis in Plasmodium berghei infected mice

Abstract

BackgroundMalaria is a major public health problem in the world which is responsible for death of millions particularly in sub-Saharan Africa. Today, the control of malaria has become gradually more complex due to the spread of drug-resistant parasites. Medicinal plants are the unquestionable source of effective antimalarials. The present study aimed to evaluate antiplasmodial activity and acute toxicity of the plant Strychnos mitis in Plasmodium berghei infected mice.MethodsStandard procedures were employed to investigate acute toxicity and 4-day suppressive effect of crude aqueous and hydro-methanolic extracts of the leaves of Strychnos mitis against P. berghei in Swiss albino mice. Water, n-hexane and chloroform fractions, obtained from crude hydro-methanolic extract, were also tested for their suppressive effect against P. berghei.ResultsAll crude extracts revealed no obvious acute toxicity in mice up to the highest dose administered (2000 mg/kg). All crude and solvent fractions of the leaves of Strychnos mitis inhibited parasitaemia significantly (p < 0.01). At the highest dose of 600 mg/kg, both aqueous and hydro-methanolic extracts demonstrated higher performance with 95.5 and 93.97% parasitaemia suppression, respectively. All doses of crude extracts and fractions of leaves of Strychnos mitis prolonged survival time of infected mice dose dependently. The highest two doses of the crude aqueous and hydro-methanolic extracts, and chloroform and aqueous fractions prevented weight loss in a dose dependent manner. Whereas, all doses of n-hexane fraction prevented loss of body weight but not in a dose dependent manner. The crude aqueous extract at the doses of 400 mg/kg and 600 mg/kg and hydro-methanolic extract at all dose levels significantly (p < 0.01) prevented packed cell volume reduction. Crude aqueous extract at a dose of 600 mg/kg and hydro-methanolic extract at all dose levels significantly prevented temperature reduction. Phytochemical screening of the crude aqueous and hydro-methanolic extracts revealed the presence of alkaloids, anthraquinones, glycosides, terpenoids, saponins, tannins and phenols.ConclusionThe results of this study provide support the traditional therapeutic use of Strychnos mitis for treatment of malaria. However, further in-depth study is needed to evaluate the potential of the plant towards the development of new antimalarial agent.

Antimalarial Activity of the Methanol Aerial Extract of Alysicarpus glumaceus (Vahl) DC. in Plasmodium berghei Infected Mice

“…The dose-dependent reduction in parasitemia levels produced by the methanol aerial extract of Alysicarpus glumaceus (average parasitemia 20.46 ± 1.31, 15.48 ± 1.37 and 12.26 ± 0.79 at 250, 500, and 1,000 mg/kg, respectively), is an indication of the extracts ability to inhibit the proliferation of Plasmodiumparasite in mice (Figure 3). The current finding agreed with other reports on medicinal plants used for malaria, such as Indigofera spicata, 8 Strycnos mitis 21 and Trema orientalis. 23 The oral median lethal dose was estimated to be greater than 5,000 mg/kg as there was no mortality recorded after the first and second phases of the acute toxicity study.…”

“…This could be due to recrudescence Key: + = present, -= absent of P. berghei parasites after apparent cure. 21 According to Mbah et al, 22 the curative property of potential antimalarial agents of plantbased origin should be detectable during screening for antimalarial activity. Thus, the ability of the extract to decrease parasitemia levels and prolong survival time suggests that it has antimalarial activity.…”

Evaluation of in vitro and in vivo Antiplasmodial Activity of the Leaf Latex of Aloe Weloensis (Aloaceae)

“…Plant extracts are considered active when reduction or percentage suppression in parasitemia is ≥ 30% or signi cant prolonging the survival time of treated mice compared to the vehicle control (38)(39)(40). Thus, the leaf latex of A. weloensis was found to be active against P. berghei infected mice.…”

Phytochemical-constituents, safety and efficacy of commonly used medicinal plants for the treatment of malaria in Ethiopia-a review

“…Phytochemistry: Phytochemical screening of hydromethanolic leaves of S. mitis showed the presence of different secondary metabolites like alkaloids, tannins saponins, flavonoids Terpenoids, Steroid, phenols and glycosides which is comparable with other species of the plant. 55,56 Safety and toxicity: Selamawit et al, 55 investigated the acute toxicity study of S. mitis indicated that both hydromethanolic and aqueous extract of S. mitis leaves caused no mortality up to 2000mg/kg oral doses within the first 24 hours as well as for the following 14 days and the experimental mice who ingested the crude aqueous, chloroform and methanol leaf extracts of S. mitis also did not show any indication of gross physical or behavioral changes.…”

“…The N-hexane fraction and the higher two doses (200mg/kg and 400mg/kg) of chloroform and aqueous fraction of S. mitis leaves protected the mice from body weight loss as compared to negative control after four day suppressive test, this investigation is comparable with antiplasmodial activity of other species of Strychnos, S. usambarensis, S. icaja, S. variabilis, S.angolensis and S. memecyloides. 55,57…”