RESUMEN
Solid lipid nanoparticles incorporating Curcuma longa L., Zingiberaceae, curcuminoids were produced by the hot melt emulsion method. A Box–Behnken factorial design was adopted to study the nanoparticles production at different levels of factors such as the percentage of curcuminoids, time of homogenization and surfactant ratio. The optimized nanoparticles were incorporated into hydrogels for stability, drug release and skin permeation tests. The average nanoparticle sizes were 210.4 nm; the zeta potential of −30.40 ± 4.16; the polydispersivity was 0.222 ± 0.125. The average encapsulation efficiency of curcumin and curcuminoids was 52.92 ± 5.41% and 48.39 ± 6.62%, respectively. Solid lipid nanocapsules were obtained with curcumin load varying from 14.2 to 33.6% and total curcuminoids load as high as 47.7%. The topical formulation containing SLN-Curcuminoids showed good spreadability and stability when subjected to mechanical stress test remained with characteristic color, showed no phase separation and no significant change in pH. As a result of slow release, the nanoparticles were able to avoid permeation or penetration in the pig ear epidermis/dermis during 18 h. The topical formulation is stable and can be used in further in vivo studies for the treatment of inflammatory reactions, in special for radiodermitis.
RESUMEN
The toxic profile of lawsone (2-hydroxy-[1,4]naphthoquinone) and a series of [1,4]naphthoquinone derivatives was evaluated against the brine shrimp Artemia salina and against the mollusk Biomphalaria glabrata, the main transmitting vector of schistosomiasis in Brazil. Of the seventeen compounds tested nine fell below the threshold of 100 µg/mL set for potential molluscicidal activity by the World Health Organization. As a general rule derivatives with non-polar substituents presented the highest molluscicidal activities. These substances showed significant toxicity in A. salina lethality bioassay.
A toxicidade da lausona (2-hidroxi-1,4)-naftoquinona e de diversos derivados foi avaliada frente à Artemia salina e ao molusco Biomphalaria glabrata, o principal vetor de transmissão da esquistossomose no Brasil. Entre os dezessete compostos testados, nove apresentaram um perfil de toxicidade menor que 100 µg/mL, sendo potenciais agentes moluscicidas de acordo com as designações da Organização Mundial da Saúde. No presente estudo, os compostos contendo substituintes apolares exibiram as maiores atividades. Estes compostos também se mostraram significantemente tóxicos frente à A. salina.