MEMBRANAS DE QUITOSANA CONTENDO FRAÇÃO METANÓLICA DE Euphorbia umbellata (PAX) BRUYNS (EUPHORBIACEAE): DESENVOLVIMENTO, CARACTERIZAÇÃO E AVALIAÇÃO

Abstract

The abusive use of anti-inflammatory drugs entails health risks and this fact has increasingly led researchers to seek alternative new drugs and safer formulations.Consequently the development of new, modified drug delivery systems and the search for new drugs, presents itself as a great research field. The extracts from plant species stand out as a matrix of interest due to the presence of possible active compounds. These compounds include the class of phenolic compounds, which is a structurally diversified class whose antioxidant and anti-inflammatory activity have already been well-studied and recognised. The species Euphorbia umbellata has attracted attention in recent years in relation to its ethnopharmacological use for the treatment of cancer and inflammation and it presents as candidate to be used in formulations with antiinflammatory activity, which is especially present among in its metabolites, i.e. phenoliccompounds. Consequently, this study developed, characterised and evaluated chitosan membranes containing the methanol fraction of E. umbellata for topical application in relation to their antioxidant and antimicrobial potential. Initially, the quantitative determination of phenolic compounds (total flavonoids and phenolics) present in the crude extract and its fractions (hexane, chloroform, ethyl acetate and methanol) were performed using UV-VIS, and a qualitative chromatographic evaluation of the methanolic fraction was performed using UHPLC-MS. The physicochemical characterisation of the membranes was performed using SEM and EGF techniques,density, XRD, FTIR, DSC, TGA, colour measurements, and pharmacological evaluation in vitro by determining the scavenging (DPPH and ABTS) and antimicrobial potential, in addition to ex vivo permeation testing. The quantification of phenolic compounds demonstrated that the methanolic fraction contained the highest amount ofthese compounds (225.205 mg.g-1) and the chromatographic evaluation of themethanolic fraction made it possible to suggest 23 molecules of phenolic substances belonging to the classes of simple phenolic acids, tannins and flavonoids. The characterisation tests showed variations related to the addition of the methanolic fraction of the chitosan matrix, which showed interaction between the chitosan matrix and the polymer structure. The antioxidant and antimicrobial tests indicated the positive potential of the membranes in relation to the studied models. Similarly, these formulations also stood out in the antimicrobial assay. There was no permeation of the Franz cell model, suggesting a local activity. Thus, it was possible to demonstrate that interactions occurred between the methanolic fraction and the polymer. These formulations show promising potential for topical application in relation to antiinflammatory action.