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Background: Mikania glomerata and Mikania laevigata (guaco) extracts are popularly used for the treatment of asthma and cough as well as for their anti-inflammatory activity, indistinctly, despite their different chemical composition. Both species may present these activities however, the specific components and the cellular mechanisms are not fully identified. Objectives: To determine the activity of fractions obtained by countercurrent chromatography pooled based on their TLC and UHPLC-MS chromatographic profiles. Materials and Methods: Fractions with antioxidant activity in DPPH and ORAC tests were assayed in dystrophic primary muscle cell cultures from mdx mice, the experimental model of Duchenne muscular dystrophy (DMD), to evaluate their cellular anti-inflammatory and antioxidant activity. The inflammatory process was evaluated by determining the TNF-α, NF- κB and IL-1β content by immunoblotting; content of 4-hydroxynonenal, superoxide dismutase (SOD); catalase, glutathione peroxidase (GPx); glutathione reductase (GR) and glutathione (GSH) were determined to evaluate their antioxidant activity. Results: The crude M. glomerata and M. laevigata extracts, as well as 3 selected fractions presented antioxidant capacity in the ORAC assay and only Mlet Fr13 did not present activity by DPPH. Immunoblotting revealed no significant differences between the experimental groups, so no cellular anti-inflammatory effect was observed, however, reduced levels of anti-oxidant defence system components were observed for all fractions. Conclusion: Both species contain compounds that effectively reduced anti-oxidant defense system components, but none of these fractions significantly reduced inflammatory markers, suggesting that the reported anti-inflammatory activity of these species may be mediated by oxidative stress reduction. [ABSTRACT FROM AUTHOR]

Stingless bees are responsible for pollinating up to 90% of Brazilian flora, so their study is of commercial and ecological importance. Stingless bees mix plant resins with wax and soil, forming geopropolis. Studies of the variability in composition and activity due to species, place and season of collection are lacking. Yield, total phenolic and flavonoid content, and antioxidant activity (via DPPH) of the extracts of fifteen M. quadrifasciata (Mandaçaia) geopropolis samples collected over a year in the State of São Paulo, Brazil, as well as two samples from different regions of the state of Minas Gerais in Brazil were compared. Composition was determined by ultra-high-resolution liquid chromatography and mass spectrometry, identifying 16 compounds. The month and region of collection affected the available plant resins and influenced their yield, composition and antioxidant capacity. Depending on the place of collection, M. quadrifasciata geopropolis is a promising natural source of antioxidant phenolic compounds. [ABSTRACT FROM AUTHOR]