Avaliação in vitro da atividade antimicrobiana e antioxidante de extratos fitoterápicos produzidos na Pastoral da Saúde de Venda Nova do Imigrante-ES

Abstract

The medicinal properties of herbs used traditionally by the population have been proved by researches from all around the world. Antimicrobial and antioxidant activities of eight phytotherapeutic extracts produced in the Pastoral care of health of Venda Nova do Imigrante-ES were assessed, from the plants: Anadenanthera colubrina (Vell.) Brenan, Achillea millefolium L., Aristolochia cymbifera Mart., Casearia sylvestris Sw., Cordia verbenacea DC., Echinodorus grandiflorus (Cham.& Schltdl.) Micheli, Gossypium hirsutum L. and Plantago major L. The antimicrobial activity was evaluated by the microdiluition method for determining the minimal bactericidal concentration (MBC) of each extract against 12 bacterial species, including multi-drug resistant strains causing nosocomial infections like MRSA, VRE and ESBL K.pneumonie. All plant extracts, with the exception of A. cymbifera whose MBC > 250 mg/mL, showed antimicrobial activity against the tested bacteria, with MBC ranging between 4 and 86 mg/mL to Gram-positive bacteria and Gram-negative bacteria, with special highlights for the extracts of A. colubrina and C. verbenacea, for which there was the kinetic evaluation test of bacterial death (time-kill). The antioxidant activity of extracts was evaluated by the DPPH method, demonstrating that the extracts are herbal medicines of regular to great antioxidant action, compared to standard quercetin. The results obtained confirm empirical indications attributed to the phytotherapeutic extracts including antimicrobial action, corroborating to assign new uses for the phytotherapics evaluated, as well as to encourage further studies with the extracts and the plants from which they are derived