Updated review of the bioactive compounds isolated from Plectranthus ecklonii Benth

With an estimated 28,137 recorded medicinal plants species, it is not surprising that over 80% of the world’s population rely on traditional herbal medicines as their primary source of healthcare. In recent years, herbal medicinal use in the West has seen a resurgence, as an alternative and complementary approach to treating and preventing disease. Plectranthus species (Lamiaceae family) have widespread ethnobotanical and traditional uses, including in southern Africa to treat listeriosis, tuberculosis-related problems and skin diseases. The extensive use of these plants suggests this genus may be highly promising for the discovery of medicinal compounds, including antitumour, antimicrobial and antioxidant compounds. This review enumerates the abietane diterpene secondary metabolites, isolated to date, from the extracts and fractions of Plectranthus ecklonii Benth. Using the search terms, ‘Plectranthus ecklonii’, ‘parvifloron D’, ‘parvifloron E’, ‘parvifloron F’ and ‘sugiol’, databases, including PubMed, Web of Science and ScienceDirect, were examined. This work focuses on the documented bioactivity of the isolated active compounds, parvifloron D, E, F and sugiol, in order to consider their potential for pharmaceutical development of novel drugs.