{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T07:15:31Z","timestamp":1788246931493,"version":"build-2803163510"},"reference-count":56,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2016,1,15]],"date-time":"2016-01-15T00:00:00Z","timestamp":1452816000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004359","name":"Swedish Research Council","doi-asserted-by":"publisher","award":["2012-6074"],"award-info":[{"award-number":["2012-6074"]}],"id":[{"id":"10.13039\/501100004359","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diseases"],"abstract":"<jats:p>As 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\u2032-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\u2032-biplumbagin (5). Compounds 2, 4, and 5 showed cytotoxicity (IC50 520\u201382.1 \u03bcM) 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 &gt; 100 \u03bcg\/mL, respectively), and for the methanol extract of the stem bark (IC50 59.6 \u03bcg\/mL). The radical scavenging activity of the isolated constituents (1\u20135) 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.<\/jats:p>","DOI":"10.3390\/diseases4010003","type":"journal-article","created":{"date-parts":[[2016,1,15]],"date-time":"2016-01-15T09:26:33Z","timestamp":1452849993000},"page":"3","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Phytoconstituents with Radical Scavenging and Cytotoxic Activities from Diospyros shimbaensis"],"prefix":"10.3390","volume":"4","author":[{"given":"Per","family":"Aronsson","sequence":"first","affiliation":[{"name":"Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg SE-412 96, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1505-6309","authenticated-orcid":false,"given":"Joan","family":"Munissi","sequence":"additional","affiliation":[{"name":"Chemistry Department, College of Natural and Applied Sciences, University of Dar es Salaam, P.O. Box. 35061, Dar es Salaam 0255, Tanzania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amra","family":"Gruhonjic","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg SE-412 96, Sweden"},{"name":"Sahlgrenska Cancer Center, University of Gothenburg, Gothenburg SE-405 30, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul","family":"Fitzpatrick","sequence":"additional","affiliation":[{"name":"Sahlgrenska Cancer Center, University of Gothenburg, Gothenburg SE-405 30, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G\u00f6ran","family":"Landberg","sequence":"additional","affiliation":[{"name":"Sahlgrenska Cancer Center, University of Gothenburg, Gothenburg SE-405 30, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen","family":"Nyandoro","sequence":"additional","affiliation":[{"name":"Chemistry Department, College of Natural and Applied Sciences, University of Dar es Salaam, P.O. Box. 35061, Dar es Salaam 0255, Tanzania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0359-5970","authenticated-orcid":false,"given":"Mate","family":"Erdelyi","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg SE-412 96, Sweden"},{"name":"Swedish NMR Center, University of Gothenburg, Gothenburg SE-405 30, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,1,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1775","DOI":"10.1021\/np800298w","article-title":"Triterpenoids from the leaves of Diospyros kaki (Perimmon) and their inhibitory effects on protein tyrosine phosphatase 1B","volume":"71","author":"Thuong","year":"2008","journal-title":"J. Nat. 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