In this study was evaluated the influence of the extraction factors on the extract’s properties to improve the recovery of high concentrations of the phytochemicals important for the biological activities from pods of Libidibia ferrea (Mart. ex Tul.) L. P. Queiroz. The extracts were obtained by turbo-extraction and a factorial design 32 was used to study the importance of the drug amount (5, 10 or 15 g) and the solvent (Ethanol 40, 60 or 80%, v/v) on the variables of response, and the optimization was performed by Response Surface Methodology (RSM) and Desirability profile. Mathematical models were fitted according to experimental data and the validated equations were used to generate RSM for each dependent variable (dry residue; total polyphenol content; content of gallic acid and ellagic acid; and, efficiency of extraction). The factors studied within the applied experimental field presented different influence profiles for the responses, and significant interactions between linear and quadratic terms. The statistical analysis showed high R2 > 0.99. The RSM and Desirability (> 0.95) allowed to show that the optimum conditions to produce extractive solutions of Libidibia ferrea with high efficiency for ellagic acid and gallic acid were 15 g and ethanol 40%.

Acanthospermum hispidum DC., Asteraceae, is widely used in folk medicine in Brazil to treat respiratory diseases; this biological property has been attributed to its phytosterol content. This study evaluated the spectrophotometric assay method to quantify the total phytosterol content in raw materials and extracts from roots of A. hispidum. The procedure was based on the quantification at 625 nm after the Liebermann-Burchard reaction. The method was evaluated for linearity, repeatability, intermediate precision, accuracy and robustness. The date indicated that the procedure is a valid analytical tool for materials and herbal derivatives from A. hispidum.