Prophylactic and curative activities of extracts from Warburgia ugandensis Sprague (Canellaceae) and Zanthoxylum usambarense (Engl.) Kokwaro (Rutaceae) against Plasmodium knowlesi and Plasmodium berghei

Abstract

This work reports the anti-plasmodial activities of Warburgia ugandensis and Zanthoxylum usambarense commonly used as phytomedicines against malaria by some Kenyan communities. AIM OF STUDY:To determine the anti-plasmodial activities of extracts from Warburgia ugandensis and Zanthoxylum usambarense against Plasmodium knowlesi and Plasmodium berghei. MATERIALS AND METHODS:Eight plant extracts were screened for in vitro anti-plasmodial activity against Plasmodium knowlesi, in a 96-well plate incubated at 37 degrees C on a RPMI culture medium supplemented with baboon serum. Of the eight, three were investigated for prophylactic and curative activities in BALB/c mice against drug-sensitive Plasmodium berghei in a 4-day test at a dose rate of 200mg/kg/day. RESULTS:Inhibitory concentrations (IC(50)) values of between 3.14 and 75 microg/ml, up to 69% chemosuppression of parasites growth and over 80% survivorship of treated mice were observed. CONCLUSION:The two medicinal plants, Warburgia ugandensis and Zanthoxylum usambarense possess bioactive compounds against malaria parasites and could be exploited for further development into malaria therapy.

Antimicrobial drimane sesquiterpenes and their effect on endophyte communities in the medical tree Warburgia ugandensis

“…Preliminary phytochemical analysis revealed qualitative as well as quantitative differences in the drimane sesquiterpene profiles of individual trees grown at the same location as well as of the different organs of one tree. Consequently, the pepper bark tree represents an interesting model to explore relationships between microbial endophytes and host plant secondary metabolites, not only in terms of obtaining insights on how those interactions affect biodiversity and community composition, but also in terms of how the content of active constituents in plants that are used in traditional medicine—drimane sesquiterpenes from Warburgia are even considered as anti-malaria drugs (Were et al, 2010; Wube et al, 2010)—can be affected by colonization with endophytic microbes.…”

Zanthoxylum Genus as Potential Source of Bioactive Compounds

“…The aqueous extract was remarkably active against the two parasites, while all organic solvents extracts being inactive. These results suggest that the antiplasmodial activity of Z. usambarense is due mainly to polar substances (Were et al, 2010).…”

Antiplasmodial Activities of the Stem bark Extract and Compounds of Zanthoxylum gilletii (De wild) P.G. Waterman

“…16,17 In a separate study, the water extract of the stem bark of Z. usambarensis which is commonly used in Kenyan traditional medicine, exhibited good anti-plasmodial activities against P. knowlesi with an IC 50 value of 6.04 ± 0.11 µg/ml. 18 Similarly, the methanol extract of the stem bark of this plant was more potent, with IC 50 values < 6 μg/ml compared with the aqueous extract which showed IC 50 values between 6 and 15 μg/ml against both chloroquine-sensitive and resistant P. falciparum isolates. 19 Furthermore, the stem bark extracts have shown interesting vitro anti-plasmodial activities in previous studies exhibiting IC 50 >5 µg/mL.…”