RESUMO
Isolation of the furocoumarins (psoralens) bergapten, isobergapten, sphondin, isopimpinellin and pimpinellin from the Umbilliferous plant Heracleum laciniatum was carried out by column chromatography, and the structure and absorption spectra for the 5 furocoumarins isolated are described. Photoepicutaneous testing showed the strongest phototoxic effects from bergapten, marked effects from pimpinellin, weak effects from sphondin and none from the others. These in vivo findings were confirmed by the in vitro Candida test. Action spectrum studies demonstrated peak photosensitivity in the range 330-335 nm, bergapten being more than twice as phototoxic as pimpinellin.
Assuntos
Furocumarinas/isolamento & purificação , Transtornos de Fotossensibilidade/induzido quimicamente , Plantas/análise , 5-Metoxipsoraleno , Furocumarinas/efeitos adversos , Humanos , Metoxaleno/isolamento & purificação , Testes Cutâneos , Espectrofotometria UltravioletaRESUMO
Experimental phytophotodermatitis was produced using homogenates from different parts of Heracleum laciniatum and long-wave ultraviolet light. The homogenates of leaves and flowers produced strong phototoxic reactions, fruit slightly less. Stems were either non-phototoxic or only slightly phototoxic. The roots of young plants did not evoke photosensitivity reactions, whereas the roots of older plants were strongly phototoxic; even roots collected from the frozen ground in December elicited strong reactions. Abdominal and midback skin were more photosensitive than skin of the lateral aspects of the underarms and legs.
Assuntos
Transtornos de Fotossensibilidade/etiologia , Extratos Vegetais/toxicidade , Candida albicans/metabolismo , Candida albicans/efeitos da radiação , Humanos , Técnicas In Vitro , Extratos Vegetais/metabolismo , Extratos Vegetais/efeitos da radiação , Plantas/metabolismo , Estações do Ano , Testes CutâneosRESUMO
Phytophotodermatitis from Heracleum laciniatum is described in 2 typical cases. Experimental phytophotodermatitis was produced using homogenates from leaves of the plant and long-wave ultraviolet light. The homogenates of leaves produced strong phototoxic reactions. The minimal phototoxic erythema dose was determined to be lowest for abdominal and midback skin. The action spectrum for Heracleum laciniatum homogenates applied topically was found to be in the range 315-375 nm with peak sensitivity at 330-335 nm.
