Caracterização química e biológica in vitro de extratos de Garcinia brasiliensis e avaliação do seu perfil de permeação cutânea em formulações dermatológicas.

Abstract

The species Garcinia brasiliensis Mart. (synonym: Rheedia brasiliensis Planch and Triana) is a plant also known as "bacuri”. It is a specie commonly used for its pharmacological property. The present study aims to chemically characterize and evaluate the biological activity of ethanol and aqueous extracts of leaves, bark and seeds of G. brasiliensis. The contents of total phenolics, flavonoids and antioxidant activity were evalueted. The leaf aqueous extract showed a high content of phenolic compounds with 343.98 ± 4.8 mg GA / g. The most significant amounts of flavonoids were found in the seed’s ethanolic extract and leaf’s aqueous extract, respectively, with values of 47.10 ± 0.2 and 45.62 ± 0.7 mg of quercetin / g of extract. For antioxidant activity, the most active was the seed’s ethanolic extract, with 86.57 % of scavenging activity. The antimicrobial activity was evaluated by microdilution plate test for bacteria and fungi. Considering the MIC50, the leaf’s aqueous extract was the most active, with a MIC50 of 1 mg / mL, activity very close to chloramphenicol as standard, which showed a MIC50 of 0.975 mg / mL against the bacteria S. aureus. For antifungal activity, no extract showed activity against C. albicans in the range of tested concentrations. Excluding the leaf’s ethanolic extract, all other extracts were considered bioactive against C. krusei. The chemical characterization by high performance liquid chromatography was performed on the leaf’s aqueous extract and it was detected the presence of fukugetin-7''-O-β-D- glucoside (fukugeside) and fukugetin. With this same extract it was carried out cytotoxicity tests in human fibroblasts and tumor cell lines, showing no toxicity of the cell’s cultures tested. Formulations containing G. brasiliensis aqueous extract were prepared and skin permeation and retention tests on "Franz cell" were performed. For being a natural product derived from a renewable source like leaves, this extract is a potential candidate of new drugs development for skin lesions treatment caused by microorganisms tested.