Análise da extração de vitamina a em leite e polivitamínico através de um planejamento fatorial

Abstract

Vitamin A plays essential role in the body development, in particular, vision and immune system. This compound can been obtained from synthetic or natural source. Several works show the viability of quantification through different analytical methods, however some difficulties still have not been overcome, for example, extraction conditions. Furthermore, there is no one extraction methodology defined to be suitable for every type of matrix. The aim of this study was to evaluate, through factorial design 23 the extraction of vitamin A through saponification technique when KOH concentration, reaction time and volume of extractive solution are modified. The concentration of vitamin extracted was used as response. The analysis were performed by HPLC (C18, 150 x 4.6mm). Isocratic condition with mobile phase methanol: acetonitrile (80:20) results in run time of 5 min with retention time of 3,5min to retinol. The linearity of the calibration curve obtained by external standard was 0.1 to 600 µg/mL. The maximum response obtained was found to both matrixes when KOH concentration was 10% (w/v), however to polivitamin matrix the volume of extractive solution and its interaction with the reation time were statistically significant (p-value = 0,1). The results corroborate with others reported in the literature, but the results achieve in this work suggest model adjustments and investigation of the influence of matrix effect and solvents in the extraction.