Caracterização química e avaliação das atividades antioxidante, anti-tumoral, anti-inflamatória e antimicrobiana dos extratos de folhas e flores de Eupatorium inulaefolium

Abstract

Eupatorium inulaefolium (Kunth) R. M. King & H. Rob., popularly known as “cambará de bicho”, “cambará” or “circuta galega ” is a native and not endemic plant species in Brazil and traditionally used in the treatment of throat diseases, anemia, tuberculosis and ocular inflammation. Despite its popular use, few studies have been carried out to evaluate its biological activities as well as to confirm its constituents.The present study aimed to chemically characterize and investigate the antioxidant,antitumor.The present study aimed to chemically characterize and investigate the antioxidant, antiinflammatory and antimicrobial potentials in vitro extracts of hexane (EHFA, EHFR), ethyl acetate (EAFA, EAFR) and methanol (EMFA, EMFR) from its leaves and flowers. The antioxidant activity was evaluated by Radical Sequestration DPPH, Phosphomolybdenum and Co-oxidation assay of the β-carotene / linoleic acid. Cultures of J774A.1 cells were used to assess cytotoxicity (MTT test) and antiinflammatory activity (nitrite assay - Griess reaction). In vitro antimicrobial activity was investigated by determining the Minimum Inhibitory Concentration (MIC) using broth microdilution using different strains of fungi and bacteria. In addition, the quantitative evaluation can be done through the parameters of total activity, percentage of activity and index of susceptibility. Phenol and flavonoid were determined by colorimetric and/or turbidimetric methods. The chemical characterization was performed with gas chromatography coupled to the mass spectrometer (CG-EM) and ultra-efficient liquid chromatography coupled to mass spectrometry (UFLC-QTOF-MS). The EMFA and EMFR extracts presented 50% Effective Concentration (IC50) ranged from 11,30 and 12,70 μg/mL, respectively, by DPPH assay. In phosphomolybdenum, EMFA presented 134,23% regarding rutin and 111,19% regarding quercetin. Also, in β-carotene / linoleic acid, EMFR presented Lipid Peroxidation Inhibition (I%) 55,58%. Besides, in vitro tests revealed that, at the tested concentrations (between 100 and 6,25 µg / mL), no extract reduced the viability of J774A.1 cells to levels below 70%, following ISO10993-5: 2009. Regarding anti-inflammatory activity, EAFA extracts (100 µg / mL) and EAFR (all concentrations) were more expressive, significantly reducing the production of nitric oxide. The extracts showed promising antimicrobial activity concerning the tested strains. About the total phenol and flavonoid contents the extracts EMFA and EMFR presented 109,50 and 142,55 μg / mg and 93,04 and 102,88 μg / mg respectively. The EHFA and EHFR extracts, triterpenes derived from alpha and beta amirine acetate and taraxasterol acetate were isolated and identified. While, in the extracts EAFA, EAFR, EMFA and EMFR the following substances 6-methoxyikaempferol were identified; methoxylated tetrahydroxyflavone; trihydroxy-tetramethoxy flavone; eupatorine and himenoxin.To sum up, we can suggest that E. inulaefolium has the potential for antioxidant, antifungal and anti-inflammatory activities. Further studies should be carried out to confirm its therapeutic importance, and to relate it to the phytochemicals present in the species.