Candidacidal potential of licorice phenolic extract: emphasis on its mode of action

Medicinal plants bave gained a special attention in the last years, due to its renowned health benefits, such as antimicrobial effects [I]. In fact, several natural matrices bave been increasingly studied, namely for its antifungal activity against opportunistic fungi [2,3]. Candida species, although commensa! microorganisms, have caused severe organic dysfunctions to the host, once current antifungal agents have lost their recognized efficiency [2]. So, numerous studies have been carried out focusing the mechanisms of acquired drug-resistance by Candida species [promissory candidacidal effects, and therefore, the involved mechanisms of action need to be clarified. Thus, in the present study these modes of action were assessed, by using flow cytometry.Overall, the licorice extract induced significant and irreversible primary damages on Candida cells, being membrane disruption and consequent unviability one of the main targets. In fact, after membrane destabilization, cells lost their proper homeostasis, their metabolic functions were blocked and, consequently cells lost functionality. The relevance and interest of the achieved results open new insights towards the upcorning use of the present phenolic matrix, being important to evaluate its in viva efficacy. Therefore, further studies are necessary to deepen knowledge on this field, aiming not only to establish therapeutic and prophylactic doses, but also to improve the clinical intervention in Candida infections.

Síntese e impregnação de peneiras moleculares Fe MCM-41 derivada de sílica da casca do arroz

The mesoporous molecular sieves of the MCM-41 and FeMCM-41 type are considered promissory as support for metals used as catalysts in oil-based materials refine processes and as adsorbents for environmental protection proposes. In this work MCM-41 and FeMCM41 were synthesized using rice husk ash - RHA as alternative to the conventional silica source. Hydrothermal synthesis was the method chosen to prepare the materials. Pre-defined synthesis parameters were 100°C for 168 hours, later the precursor was calcinated at 550°C for 2 hours under nitrogen and air flow. The sieves containing different proportions of iron were produced by two routes: introduction of iron salt direct synthesis; and a modification post synthesis consisting in iron salt 1 % and 5% impregnation in the material followed by thermal decomposition. The molecular sieves were characterized by X ray diffraction XRD, Fourier transform infrared spectroscopy FT-IR, X ray fluorescence spectroscopy XFR, scanning electronic microscopy SEM, specific surface area using the BET method, Termogravimetry TG. The kinetic model of Flynn Wall was used with the aim of determining the apparent activation energy of the surfactant remove (CTMABr) in the MCM- 41 porous. The analysis made possible the morphology characterization, identifying the presence of hexagonal structure typical for mesoporous materials, as well as observation of the MCM41 and iron of characteristic bands.