Modelo analítico para caracterização de droga vegetal de folhas da Schinopsis brasiliensis Engler em diferentes granulometrias

Abstract

The use of natural products and herbal medicines is one of the factors that has driven the verification and correlation between popular knowledge and scientific data. In this perspective, Schinopsis brasiliensis E. is a tree widely used in traditional medicine for several pathologies, such as inflammation, infection, candidiasis, etc. The leaves of this species are used as raw material for the production of teas, however, it is necessary to standardize the vegetal drug as a way of guaranteeing quality, safety and efficacy, besides enabling the use of this species as a candidate for the development of herbal medicines. Therefore, the objective of this work was to analyze the vegetal drug produced by the leaves of S. brasiliensis in different granulometric sizes by analytical, physical-chemical, chemometric and biological methods. For this, the leaves were collected in the semi - arid region of Paraíba, were dried, pulverized and separated by granulometry of the powders. Experimental design was used to evaluate the antimicrobial profile through the microdilution method in broth, to evaluate the minimum inhibitory concentration. In the planning the sieve size and infusion concentration were the independent variables, which were analyzed using the near infrared spectrum. After the analyzes, the following chemometric techniques were applied: hierarchical group analysis (HCA), principal component analysis (PCA) and solft independent modeling by class analogy (SIMCA). Optical microscopy was used to evaluate particle morphology and uniformity, as well as high performance liquid chromatography (HPLC) and ultraviolet spectroscopy for quantification of secondary metabolites and qualitative evaluation of chemical marker. Thermoanalytical methods were also applied to characterize the plant drug through thermogravimetry (TG) and differential thermal analysis (DTA). As a result, the leaves had a potential antifungal effect against strains of Candida spp., and it was observed that the decrease and uniformity of particle size favors this action. The result is corroborated with the chemometric data that can separate the particles into small, medium and large. The morphological data presented the particles with uniform sizes, besides irregular surfaces. In relation to the chemical composition, it was possible to quantify the flavonoids content, tannins and in greater quantity, polyphenols, besides identifying gallic acid by HPLC. The thermoanalytical data also show that the thermal behavior of the particles presents uniform characteristics and variations according to the size and heating ratios.Therefore, this plant drug is promising in relation to studies of phytotherapeutic development, as well the analytical model presented can be used as tool for characterization of plant parts.