Avaliação in vitro dos potenciais antifúngico, antibiofilme e antiproliferativo do extrato da Guaripa graciliflora Mart.

Abstract

Guapira graciliflora Mart. is a medicinal plant, commonly found in the caatinga, in the Brazilian semi-arid and widely used by the local population because of their antituberculosis, anti-inflammatory and healing activities. The aim of this study was to evaluate in vitro the antifungal, antibiofilm and antiproliferative potential of G. graciliflora. A hydroalcoholic extract of G. graciliflora‘s leaves was obtained. Then, the extract was fractionated by filter column on fritted funnel. The chemical characterization of the extracts was performed by G Electrospray Ionization Mass Spectrometry (ESI-MS). The antifungal activity of graciliflora extract and its fractions was evaluated by broth microdilution method to determine the Minimum Inhibitory and Fungicidal Concentrations (MIC / MFC) against Candida albicans ATCC 10231; Candida glabrata CBS 07; Candida krusei CBS 573 and Candida dubliniensis CBS 7889. The ability to inhibit formation of a C. albicans biofilm was evaluated considering the number of colony forming units (CFU/ml), the cell metabolic activity (MTT) and hydrogenic potential (pH). The antiproliferative activity of the extract and its fractions were evaluated against human tumoral cell lines (U251, MCF-7, NCI-ADR/RES, 786-0, NCI-H460, PC-3, HT-29) and not tumoral cell line (HaCat) by Sulforhodamine B assay. The cytotoxicity of the extract was evaluated on the line RAW 264.7 macrophages also by Sulforhodamine B assay. The phytochemical characterization of the extract indicated the suggestive presence of the flavonoids rutin and kaempferol. The extract and its methanol fraction showed moderate antifungal activity against C. albicans, C. glabrata and C. krusei and strong activity against c. dublniensis. The analysis about the metabolic activity and the number of viables cells at 24 and 48 hours biofilms showed diference (p < 0,05) only for the number of viables cells at 24 hours and the metabolic activity at 48 hours, with the extract‘s concentrations of 125 µg/mL and 62,5 µg/mL reducing the major number of CFU/mL (34,1% and 36,9%. respectively) and the concentration of 250 µg/mL was the most effective in decrease the metabolic activity (50,79%) of C. albicans cells. The pH values observed in biofilms treated with the extract were higher than those observed in untreated biofilm. The extract and its fractions have no antiproliferative effect against tumor cell lines tested, with average activity (mean log GI50) greater and equal to 1.71 mg/mL. Cell viability of macrophages was maintained above 80% for the extract concentrations up to 62,5 mg/mL. The extract of G. graciliflora‘s leaves has flavonoids is its chemical composition. Also has antifungal and antibiofilm potential, without significance evidence of antiproliferative activity against tumor and not tumor cell lines.