Composição química e avaliação das atividades biológicas dos extratos vegetais e do óleo essencial das folhas de Myrsine umbellata Mart. (Primulaceae)

Abstract

The interest in active compounds with biological potential of native Brazilian plants has been growing year after year. The arboreal species Myrsine umbellata Mart. (Primulaceae) Known as capororoca, they have their shells used in the treatment of diseases of the liver, urinary system and skin (leprosy). Thus, the objective of the study was to carry out phytochemical prospecting through colorimetric tests to determine the groups of secondary metabolites present in the different plant extracts tested and in the essential oil of the leaves of M. umbellata through gas chromatography coupled to mass spectrometry (CG-EM), as well as investigating antimicrobial activity against the twelve standard ATCC strains by the broth microdilution technique; the antioxidant potential by the DPPH method and the antibiofilm potential on the biomass of biofilms of standard bacteria by the crystal violet technique and tetrazolium salt reduction assay (MTT). Phytochemical prospecting of the extracts detected the presence of free steroids, alkaloids, anthocyanins, anthocyanidins, flavonoids (flavones, flavonools, flavonols and xanthons), tannins and saponins. n the analysis of the essential oil the identified majority compounds were elixene, caryophyllene (E), espatulenol, d-Cadinene and aromadendrene. The extracts that presented the best results were: methanol with antimicrobial activity against the Gram-positive strain Staphylococcus epidermidis (CIM 3.12 and CBM 6.25), antioxidant percentage of 92.58% and antibiofilm action against the biofilm of the Gram-strainpositive Staphylococcus aureus with inhibition of biomass in 92.58% and cell viability of 17.88%. The acetonic with antimicrobial activity with CIM and CBM/CFM values ranging from 3.12 to 100 mg.mL-1, highlighting its efficiency over the Gram-positive strain Staphylococcus epidermidis, its antioxidant potential of 89.55%. The antibiofilm potential was also observed in the ethanolic that reduced the biofilm biomass of all bacteria tested with high activity (63.41% to 83.65%) and in the essential oil with antibiofilm potential of 84.96% compared to the biofilm of the Salmonella enterica Enteritidis strain. These results indicate the potential of extracts and essential oil of M. umbellata as a source of plant bioactive for the development of new alternative strategies for the control of resistant microorganisms.