Phytochemical characterization, and antioxidant and antibacterial activities of the hydroethanolic extract of Anadenanthera peregrina stem bark

Abstract

Abstract The Brazilian Cerrado biome consists of a great variety of endemic species with several bioactive compounds, and Anadenanthera peregrina (L.) Speg is a promising species. In this study, we aimed to perform phytochemical characterization and evaluate the antioxidant and antibacterial activities against Staphylococcus aureus and Escherichia coli of the hydroethanolic extract of A. peregrina stem bark. The barks were collected in the Botanical Garden of Goiânia, Brazil. The hydroethanolic extract was obtained by percolation and subjected to physicochemical screening, total phenolic content estimation, high-performance liquid chromatography (HPLC) fingerprinting, and antioxidant (IC50 values were calculated for the 2,2-diphenyl-1-picrylhydrazyl assay - DPPH) and antibacterial activity determination. The pH of the extract was 5.21 and density was 0.956 g/cm3. The phytochemical screening indicated the presence of cardiac glycosides, organic acids, reducing sugars, hemolytic saponins, phenols, coumarins, condensed tannins, flavonoids, catechins, depsides, and depsidones derived from benzoquinones. The extract showed intense hemolytic activity. The total phenolic content was 6.40 g GAE 100 g-1. The HPLC fingerprinting analysis revealed the presence of gallic acid, catechin, and epicatechin. We confirmed the antioxidant activity of the extract. Furthermore, the extract did not inhibit the growth of E. coli colonies at any volume tested, but there were halos around S. aureus colonies at all three volumes tested. These results contribute to a better understanding of the chemical composition of A. peregrina stem bark and further support the medicinal applications of this species.