Ruth Anyango Omole1,2,*, Mainen Julius Moshi1, Matthias Heydenreich3, Hamisi Masanja Malebo4, Jeremiah Waweru Gathirwa5, Richard Owor Oriko6, Leonida Kerubo Omosa6, Jacob Ogweno Midiwo6
1Institute of Traditional Medicine, Muhimbili University of Health and Allied Sciences, Dar es Salaam, TANZANIA.
2Department of Chemical Science and Technology, Technical University of Kenya, Nairobi, KENYA.
3Institut für Chemie, Universität Potsdam, OT Golm, Haus 25, D/0.19 (Labor E/0.06-0.08), Karl-Liebknecht-Str. 24-25, D-14476 Potsdam, GERMANY.
4Department of Traditional Medicine Research, National Institute for Medical Research, Dar es Salaam, TANZANIA.
5Centre for Traditional Medicine and Drug Research, Kenya Medical Research Institute (KEMRI), Nairobi, KENYA.
6Department of Chemistry, University of Nairobi, Chiromo Road, Nairobi, KENYA.
Introduction: Plants of the genus Garcinia are traditionally used treat a range of infectious and non-infectious diseases. Garcinia species are reported to have been shown to have a range of biological activities including cytotoxicity antimicrobial, antifungal, antioxidant, antimalarial and HIV-1 protease inhibitory activity among others. Methods: Solvent extraction was done using CH2Cl2: MeOH (1:1). Isolation was done using column chromatography with silica gel as the stationery phase and ethyl acetate and n-hexane used as mobile phase in increasing polarity. Thin layer chromatography was used to monitor the isolation. Structure elucidation was done using nuclear magnetic resonance and mass spectroscopic techniques. Chloroquine resistant (W2) and chloroquine sensitive (D6) P. falciparum strains were used for antiplasmodial assay. Results: Further bioassay guided fractionation of a CH2Cl2: MeOH (1:1) extract of Garcinia buchananii led to the isolation of two already reported biflavanones, isogarcinol (1) and guttiferone (2) with promising antiplasmodial activity against a chloroquine resistant (W2) Plasmodium falciparum strain with an IC50 of 2.8 ± 0.90 μg/mL for compound 1 and IC50 of 3.94 ± 0.38 μg/mL for compound 2. Compounds 1 and 2 also exhibited moderate activity against the chloroquine sensitive (D6) Plasmodium falciparum strain with IC50 of 7.03±0.60 and 10.64±4.50 μg/mL, respectively. Conclusion: The results provide proof to support the use of G. buchananii by the indigenous community for antimalarial therapy.