O extrato etanólico das folhas de Nectandra grandiflora coletadas na Mata Atlântica, Brasil, mostrou atividade antioxidante frente ao β-caroteno em teste usando cromatografia em camada delgada. O fracionamento biomonitorado levou ao isolamento do ácido protocatecuico e de dois flavonóides glicosilados: afzelina e quercetrina, os quais exibiram atividade sequestradora de radicais livres frente a...

The sampling tube, an open-ended polyethylene feeding catheter sterilised by the manufacturer, is filled with sterile distilled water. A 2.0% suspension of agar in distilled water is prepared and enough cochineal to colour the solution is added. This is autoclaved at 44N/10 min to dissolve and sterilise the agar. When the solution has cooled to 60°C an 8 cm length of the coloured agar solution ...

Our cultural heritage is constituted by irreplaceable artworks that must be known and preserved. Their study and documentation should be in principle carried out using non-invasive approaches. The technological advances in spectroscopic imaging acquisition devices made it possible to apply this methodology to such purpose. In this context, the present paper discusses a particularly challenging ...

key words: 1064 nm dispersive Raman spectroscopy, pigment analysis, traditional red artists’ colorants Raman spectra of red colorants were obtained in-situ using a dispersive Raman microscope equipped with a 1064 nm laser source and InGaAs array detector. By employing nearIR excitation, the fluorescence of organic colorants is significantly reduced compared to visible wavelengths. Spectra prese...