RESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: The stem bark of Garcinia livingstonei is used traditionally as a skin lightening agent. AIM OF THE STUDY: To isolate and identify compounds responsible for the observed skin lightening activity of Garcinia livingstonei and to evaluate their cytotoxicity. MATERIALS AND METHODS: Constituents of the stem bark and fruits of Garcinia livingstonei were isolated using chromatographic techniques and structures were determined using 1D and 2D NMR and MS analysis. MeWo cells were used to evaluate the cytotoxicity and impact on melanin levels of extracts and compounds isolated, in vitro. RESULTS: Twelve known compounds, morelloflavone (1), morelloflavone-7â³-sulphate (2), guttiferone A (3), sargaol (4), isojacareubin (5), 6-deoxyisojacareubin (6) and in addition to the common triterpenoids, betulin, betulin aldehyde, lupeol, lupenone, euphol and stigmasterol were isolated in this investigation. Morelloflavone, morelloflavone-7â³-sulphate and sargaol, were found to be considerably less cytotoxic and more effective as skin lightening agents than hydroquinone. CONCLUSIONS: A range of compounds was isolated from the stem bark and fruit of Garcinia livingstonei. Although the bark extract contained the cytotoxic guttiferone A, it was found to be less toxic than hydroquinone, and morelloflavone, the 7â³-sulphate derivative and sargaol show potential for development as depigmentation/skin lightening agents.
Asunto(s)
Garcinia , Melaninas/metabolismo , Extractos Vegetales/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Frutas , Humanos , Corteza de la PlantaRESUMEN
Clays have been used in southern Africa as photoprotectants by the indigenous people. Typically, two types of clay are used: one white in colour and the other red. In this work, the two clays were identified and characterized, and their in vitroâ SPF values measured. The clays afford a low SPF but offer broad-spectrum protection. No cutaneous side effects from the use of these clays are known. Further consideration should be given to the potential use of clays in sunscreen preparations.
Asunto(s)
Silicatos de Aluminio/análisis , Protectores Solares/análisis , Silicatos de Aluminio/química , Silicatos de Aluminio/uso terapéutico , Arcilla , Humanos , Sudáfrica , Protectores Solares/química , Protectores Solares/uso terapéuticoRESUMEN
A new triterpenoid, 3-oxo-22alpha-hydroxy-olean-12-en-28-oic acid (1), oleanolic acid (2) and a known iridoid, 10-hydroxy-1-oxo-7-iriden-11-oic acid methyl ester (3) have been isolated from the dichloromethane extract of the dried seeds of Gardenia volkensii. Their structures were established by 1D and 2D NMR spectroscopic and MS methods.