Composition and biological activity of Brazilian rose pepper (Schinus terebinthifolius Raddi) leaves

The leaves of Schinus terebinthifolius Raddi (Anacardiaceae), the Brazilian pepper tree, are widely used in folk medicine for treating human diseases caused by microorganisms. The aim of the present study was to investigate the antioxidant and antimicrobial activity and the chemical composition of S. terebinthifolius leaf extract and essential oil. Essential oil from fresh leaves of S. terebinthifolius was obtained in a Clevenger-type apparatus. Ethanol leaves extracts were prepared by maceration and ultrasound assisted extraction. Antimicrobial activity was tested at concentrations up to 1000μg/ml by the microdilution test after 24h and antioxidant activity was investigated using the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging assay. Phenolic compounds were determined by the Folin–Cioucalteu method and flavonoids by the aluminum chloride technique. The chemical composition of the essential oil and the extracts were characterized by GC/MS and LC–MS/MS, respectively. Ultrasound assisted extraction exhibited higher yield (182.25±3.00mg/g) and flavonoid content (243.09±8.83mg/g), while the extraction method of maceration showed higher content of total phenolic compounds (221.63±2.58mg/g) and exhibited strong antioxidant activity (IC50 15.43μg/ml). All extracts showed strong antimicrobial activity against Staphylococcus aureus and Escherichia coli. Thirty-two constituents were identified in the oil (97.90% of the total), with δ-3-carene (68.78%), E-caryophyllene (8.22%), myrcene (6.78%) and α-pinene (4.05%) as the main compounds. Mass spectrometry analyzes revealed that ferulic and caffeic acids, and quercetin were the major components in the extracts. In summary, these findings demonstrate the potential antioxidant and antimicrobial activity of extracts that may help to explain the popular use for urinary tract infection of S. terebinthifolius.