RESUMO
Abstract The study is aimed to assess the compatibility of bilberry leaf powder extract (BLPE) with six excipients selected for sustained-release (SR) tablet formulation. The BLPE was obtained with the addition of L-arginine and Myo-inositol as the carriers. Thermogravimetric (TG-DTG) analysis and Fourier-transform infrared spectroscopy (FTIR), supported by Pearson correlation analysis, were applied to detect possible interactions in the binary mixtures (1:1) of the BLPE with each excipient. The TG-DTG showed some deviations in the thermal behavior of the BLPE / excipient mixtures. However, only the thermal behavior of magnesium stearate in the mixture significantly differed from individual samples, which suggested chemical interaction for this excipient. The FTIR analysis confirmed that the BLPE is compatible with Eudragit L100, Methocel K4M, Methocel K100LV, Avicel PH-101, and Plasdone S-630. Whereas it undergoes solid-state chemical interaction in the binary mixture with magnesium stearate. According to the FTIR-spectra, it is suggested that this interaction results in the formation of stearic acid and alkalization of the medium. These findings evidence for the possibility of using TG-DTG analysis as an independent thermal technique for compatibility studies and also confirm the earlier reported interaction of basic lubricants, e.g., stearic salts, with active ingredients containing amino groups.
Assuntos
Comportamento , Extratos Vegetais/análise , Folhas de Planta/classificação , Vaccinium myrtillus/efeitos adversos , Vaccinium myrtillus/metabolismo , Preparações de Ação Retardada/análise , Análise Espectral/instrumentação , Termogravimetria/instrumentação , Espectroscopia de Infravermelho com Transformada de Fourier/métodosRESUMO
This study presents unpublished data on the chlorogenic acid and caffeic acid content in fruits. Sixty-four fruits consumed in Brazil, most of which were produced domestically, were evaluated based on their levels of 3-caffeoylquinic acid, 4-caffeoylquinic acid, 5-caffeoylquinic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid and caffeic acid. The study investigated 15 fruits that have not been reported in the literature in relation to these compounds, including several native species. The highest concentration of mono-caffeoylquinic acid was observed in strawberry, cherry, bilberry, quince and mulberry, while the dicaffeoylquinic acid was present with highest concentration in kumquat, passion fruit and sweet granadilla. Regarding caffeic acid, the highest content was found in bilberry and yellow pitaya. Considering the sum of the concentrations of these compounds, quince, cherry, bilberry, mulberry and sweet granadilla were exceptional, with concentrations between 200.0 and 569.7â¯mgâ¯kg-1.