{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,8]],"date-time":"2026-06-08T10:12:27Z","timestamp":1780913547344,"version":"3.54.1"},"reference-count":32,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,19]],"date-time":"2021-01-19T00:00:00Z","timestamp":1611014400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Plants"],"abstract":"<jats:p>Medicinal plants of the Plectranthus genus (Lamiaceae) are well known for their ethnomedicinal applications. Plectranthus madagascariensis, which is native to South Africa, is traditionally used in the treatment of respiratory conditions, scabies, and cutaneous wounds. The phytochemical studies of P. madagascariensis led to the isolation of five known royleanone abietanes, namely, 6\u03b2,7\u03b1-dihydroxyroyleanone (1), 7\u03b1-acetoxy-6\u03b2-hydroxyroyleanone (2), horminone (3), coleon U quinone (4), and carnosolon (5). The relative configuration of compound 2 was established by X-ray analysis. Compounds 1\u20134 showed antimycobacterial activity (Minimum inhibitory concentration for 90% inhibition, MIC90 = 5.61\u2013179.60 \u03bcM) against Mycobacterium tuberculosis H37Rv. Compound 4 and 5 showed comparable toxicity (Concentration for 50% inhibition, IC50 98.49 \u03bcM and 79.77 \u03bcM) to tamoxifen (IC50 22.00 \u03bcg\/mL) against HaCaT cells. Compounds 1\u20135 showed antioxidant activity through single-electron transfer (SET) and\/or hydrogen-atom transfer (HAT) with compound 5 being the most active antioxidant agent. Compounds 3 and 5 were isolated for the first time from P. madagascariensis. The observed results suggest P. madagascariensis as an important ethnomedicinal plant and as a promising source of diterpenoids with potential use in the treatment of tuberculosis and psoriasis.<\/jats:p>","DOI":"10.3390\/plants10010175","type":"journal-article","created":{"date-parts":[[2021,1,20]],"date-time":"2021-01-20T03:34:25Z","timestamp":1611113665000},"page":"175","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Antimycobacterial, Cytotoxic, and Antioxidant Activities of Abietane Diterpenoids Isolated from Plectranthus madagascariensis"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0569-4078","authenticated-orcid":false,"given":"Kadidiatou O.","family":"Ndjoubi","sequence":"first","affiliation":[{"name":"Chemistry Department, Cape Peninsula University of Technology, Bellville Campus, Symphony Road, Bellville 7535, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8823-2401","authenticated-orcid":false,"given":"Rajan","family":"Sharma","sequence":"additional","affiliation":[{"name":"Chemistry Department, Cape Peninsula University of Technology, Bellville Campus, Symphony Road, Bellville 7535, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4785-2609","authenticated-orcid":false,"given":"Jelili A.","family":"Badmus","sequence":"additional","affiliation":[{"name":"Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Road, Bellville 7535, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5508-3291","authenticated-orcid":false,"given":"Ayesha","family":"Jacobs","sequence":"additional","affiliation":[{"name":"Chemistry Department, Cape Peninsula University of Technology, Bellville Campus, Symphony Road, Bellville 7535, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Audrey","family":"Jordaan","sequence":"additional","affiliation":[{"name":"SAMRC\/NHLS\/UCT Molecular Mycobacteriology Research Unit Division of Medical Microbiology, University of Cape Town, Cape Town 7700, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1819-1699","authenticated-orcid":false,"given":"Jeanine","family":"Marnewick","sequence":"additional","affiliation":[{"name":"Applied Microbial and Health Biotechnology Institute, Cape Peninsula University of Technology, Symphony Road, Bellville 7535, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4146-0930","authenticated-orcid":false,"given":"Digby F.","family":"Warner","sequence":"additional","affiliation":[{"name":"SAMRC\/NHLS\/UCT Molecular Mycobacteriology Research Unit Division of Medical Microbiology, University of Cape Town, Cape Town 7700, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3877-9959","authenticated-orcid":false,"given":"Ahmed A.","family":"Hussein","sequence":"additional","affiliation":[{"name":"Chemistry Department, Cape Peninsula University of Technology, Bellville Campus, Symphony Road, Bellville 7535, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,19]]},"reference":[{"key":"ref_1","first-page":"50","article-title":"Medicinal plants: A review","volume":"3","author":"Singh","year":"2015","journal-title":"J. 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