Epi-polygodial, a drimane sesquiterpene was isolated from Drimys brasiliensis (Winteraceae). This compound demonstrated high parasite selectivity towards Trypanosoma cruzi trypomastigotes (IC50 = 5.01 μM) with a selectivity index higher than 40. These results were correlated with the effects observed when this compound was incorporated in cellular membrane models of protozoans, represented by Langmuir monolayers of dipalmitoylphosphoethanolamine (DPPE). Surface pressure-area isotherms showed that epi-polygodial expands DPPE monolayers at higher areas and condenses them at lower areas, which was attributed to the preferential interaction with the polar heads of the lipid. This mechanism of action could be corroborated with Polarization-Modulation Reflection-Absorption Spectroscopy and Brewster Angle Microscopy. These results pointed to the fact that the interaction of epi-polygodial with DPPE monolayers at the air-water interface affects the physical chemical properties of the mixed film, which may be important to comprehend the interaction of this drug with cellular membranes at the molecular level.

中文翻译：

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巴西Drimyss的表皮多角体的抗锥虫活性及其在空气-水界面的细胞膜模型中的作用。

Epi-polygodial，一种drimane倍半萜烯是从Drimys brasiliensis（Winteraceae）中分离出来的。该化合物对克鲁斯锥虫锥虫（IC50 = 5.01μM）表现出很高的寄生虫选择性，选择性指数高于40。这些结果与将这种化合物掺入原生动物的细胞膜模型中观察到的效果相关，该模型以二棕榈碳酰磷酸乙醇胺的Langmuir单层为代表。 （DPPE）。表面压力-面积等温线表明，表观多角体在较高的区域扩展了DPPE单层，在较低的区域使它们凝结，这归因于与脂质极性头的优先相互作用。这种作用机理可以通过偏振-调制反射-吸收光谱和布鲁斯特角显微镜得到证实。