Prophylactic and Curative Potency of Xylopia aethiopica "(Dunal) A. Rich." Leaf Extract on Mice Malaria Parasite (Plasmodium berghei).

Abstract

Introduction: Natural antimalaria agent have been documented in different plants materials. Medicinal plants have been part of human society for the treatment of infectious diseases. Plants have invariably been a rich source for new drugs, most especially antimalarial drugs; this has resulted to the discovery of quinine and artemisinin which are plant-based malaria drug.

Aim of the study: The study determined the qualitative and quantitative phytochemical constituents of Xylopia aethiopica leaf extract and to evaluate the curative antimalaria potency and prophylactic potentials of Xylopia aethiopica leaf extract in the management of malaria parasite in an animal mode.

Study design: This study is designed to test the curative and prophylactic effects of Xylopia aethiopica leaf extract in the treatment and prevention of malaria infection using albino mice infected with Plasmodium berghei and compare the effects with known antimalaria drug artemether lumefantrine (A-L) combination therapy using mice as experimental model.

Materials and methods: The Xylopia aethiopica leaf was collection, identification and air-dried. After air-drying, the plant material was pulverized and kept in a Ziplock bag. The pulverized plant material was macerated by soaking it in absolute methanol for 72 h. The extraction was filtered and concentrated under vacuum in a rotatory evaporator. Phytochemical constituents were determined using standard procedure. Swiss albino mouse infected with P. berghei was used for inoculum preparation. Curative and prophylactic efficacy of the extract was tested using three doses of the extract (10, 30, and 100 mg/kg), while 4 mg/kg of Artemether-Lumefantrine (A-L) standard drug was included in the study as positive control and normal saline as negative control. Parasitaemia level was determined to check the level of infection and potency of the plant product.

Results: Phytochemical analysis of the leaf extract revealed the presence of alkaloids, flavonoids, tannins, sterols, and saponins. The curative effect of Xylopia aethiopica leaf extract against Plasmodium berghei infection in mice was found to be dose-dependent. A significantly higher parasite clearance rate (p < 0.05) was observed in the artemether-lumefantrine treatment group compared to all extract-treated groups on day 1 post-treatment. However, by day 2, mice treated with 30 mg/kg (45.74%) and 100 mg/kg (46.14%) of the leaf extract showed higher parasite clearance rates than those treated with artemether-lumefantrine (35.42%). By day 5, there was no significant difference (p > 0.05) in parasite clearance between the 100 mg/kg extract group and the artemether-lumefantrine group, with both achieving a clearance rate of 99.60%. Throughout the study, both the extract (particularly at 100 mg/kg) and artemether-lumefantrine showed significantly higher parasite clearance rates (p < 0.05) compared to the negative control group. On days 4 and 5, no significant difference (p > 0.05) was observed in parasite clearance between the 100 mg/kg extract group (93.60% and 99.60%) and the artemether-lumefantrine group (92.70% and 99.60%), respectively. In prophylactic efficacy study, the extract also demonstrated dose-dependent prevention against P. berghei. Mice treated with 100 mg/kg of the extract showed significantly lower parasitemia levels (p < 0.05), with rates of 23.98%, 24.02%, and 24.08% recorded on days 1, 2, and 3, respectively, compared to other extract dosages.

Conclusion: The plant extract showed potential early-stage parasite clearance effectiveness and indicated a strong preventive potential against P. berghei infection at the application of the higher dose. The significant parasite clearance observed along with the dose-dependent preventive effect shows that X. aethiopica leaf extract has promising therapeutic and prophylactic potential.