Use of thermoanalytical analysis for the evaluation of a new raw material from Cnidoscolus quercifolius Pohl. (Euphorbiaceae)

Abstract

The wealth derived from the traditional knowledge about medicinal plants and phytotherapics resurges as an option to the undesirable effects and damages caused by synthetic drugs, also as the limited options available for some diseases. However, this does not exempt them from testing; it proves their effectiveness, quality and safety. Cnidoscolus quercifolius, known popularly as faveleira, is a characteristic plant of the Caatinga biome, widespread in popular medicine. The aim of this study was to determine physicochemical profile of the leaves from C. quercifolius by analytical methods, including electron microscopy of the particles and phytochemical, spectroscopic, thermogravimetric and hemolytic tests of the vegetal drug. Phytochemical screening showed positivity for phenols, tannins, flavonoids and steroids/triterpenoids, and the quantification assays obtained values of 74.19 mg g−1 for total polyphenols, 48.39 mg g−1 for condensed tannins and 16.72 mg g−1 for flavonoids. The SEM analysis confirmed the authenticity of the plant material used, and the ESD identified the main ions present. The infrared spectrum revealed the presence of bands characteristic of hydroxyl, C–H bond of aliphatic compounds, C≡N grouping, carbonyl, C=C bond of aromatic rings and C–O bond. The thermal profile revealed the occurrence of three mass loss events including loss of water, burning of carbohydrates and carbonized remains of organic material. The hemolytic test showed a low level of toxicity. The results showed that the analytical techniques allowed characterizing the physicochemical properties of the vegetal drug, which may be useful in studies for the production of phytotherapics.