Aronsson, PerMunissi, Joan J. E.Gruhonjic, AmraFitzpatrick, Paul A.Landberg, GöranNyandoro, Stephen S.Erdélyi, Máté2016-06-262016-06-262016-01-15Aronsson, P., Munissi, J., Gruhonjic, A., Fitzpatrick, P., Landberg, G., Nyandoro, S., & Erdelyi, M. (2016). Phytoconstituents with Radical Scavenging and Cytotoxic Activities from Diospyros shimbaensis. Diseases, 4(1), 3. http://dx.doi.org/10.3390/diseases4010003http://hdl.handle.net/20.500.11810/2678As part of our search for natural products having antioxidant and anticancer properties, the phytochemical investigation of Diospyros shimbaensis (Ebenaceae), a plant belonging to a genus widely used in East African traditional medicine, was carried out. From its stem and root barks the new naphthoquinone 8,8′-oxo-biplumbagin (1) was isolated along with the known tetralones trans-isoshinanolone (2) and cis-isoshinanolone (3), and the naphthoquinones plumbagin (4) and 3,3′-biplumbagin (5). Compounds 2, 4, and 5 showed cytotoxicity (IC50 520–82.1 μM) against MDA-MB-231 breast cancer cells. Moderate to low cytotoxicity was observed for the hexane, dichloromethane, and methanol extracts of the root bark (IC50 16.1, 29.7 and > 100 μg/mL, respectively), and for the methanol extract of the stem bark (IC50 59.6 μg/mL). The radical scavenging activity of the isolated constituents (1–5) was evaluated on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The applicability of the crude extracts and of the isolated constituents for controlling degenerative diseases is discussed.enDiospyros shimbaensisEbenaceaeTetralonesNaphthoquinoesRadical scavengingCytotoxicityMDA-MB-231DPPHJournal Article, Peer Reviewed10.3390/diseases4010003