The high prevalence of diabetes and obesity encourages research for the development of α-glucosidase inhibitors from natural sources. This study evaluated the activity of fractions obtained from Protium spruceanum branches. Anti-α-glucosidase activity was investigated in vitro using 4-nitrophenyl-α-D-glucopyranoside as the substrate, while free-radical scavenging activity was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azinobis-3-ethylbenzotiazoline-6-sulfonic acid (ABTS) assays. Furthermore, a model of oxidative stress promoted by H2O2 in fibroblasts was employed, and cell viability was determined by sulforhodamine B. Fractions inhibited α-glucosidase activity effectively, highlighting the hydromethanolic fraction (HMF). Quercitrin, isolated from the HMF, was identified by spectroscopy and quantified by a validated high performance liquid chromatography with diode array detector (HPLC-DAD) method and exhibited free radical scavenging activity comparable to the HMF. However, this flavonoid showed low anti-α-glucosidase effect, suggesting a synergism effect among several components of the HMF. This proposal is also supported by the docking results obtained by PyRx software. The compounds present in the HMF showed a noncompetitive inhibition at the in silico simulation. Finally, the HMF also protected fibroblasts against cell death induced by oxidative stress. This is the first evidence of the capacity of P. spruceanum branches to inhibit α-glucosidase activity and to counteract oxidative stress. These results encourage the use of this Brazilian plant against hyperglycemia-correlated diseases.

Chromone derivatives exhibiting high absorbance values in the UVA/UVB region were synthesized, and their photoprotective properties were evaluated. Chromones were prepared according to known literature procedures and characterized by high resolution mass spectrometry, infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy. The in vitro solar protection factor (SPF) was determined by the Mansur method and cytotoxicity was evaluated using the sulforhodamine B assay. Two of the chromones synthesized demonstrated suitable SPF values and displayed no cytotoxic effect towards MRC-5 human fibroblasts at the tested concentrations, indicating great potential for future in vivo assays and clinical trials. Finally, the lead compound was incorporated into a nanoemulsion. Nanoemulsions showed high droplet size homogeneity and excellent stability. Chromones bearing methoxy substituents were found to be the most promising compounds with ideal photoprotective properties desirable for utilization and incorporation in sunscreen formulations.

Selecting a polymer depends on its characteristics, the properties of the drug and of the remaining ingredients in the formulation. The drug, when incorporated into a polymeric matrix, can show several advantages when compared with its conventional form. In this context, this work describes the preparation and characterization of polyethylene glycol (PEG 4000) and its derivative particles loaded with benznidazole, as well as evaluates their trypanocidal activity. In this work, reactions to modify the PEG 4000 polymer and the subsequent incorporation of the benznidazole were made. The nuclear magnetic resonance (NMR) analysis confirmed the efficiency in modifying the PEG chains. The morphology of polymeric films was observed by atomic force microscopy (AFM) and showed considerable changes on the film organization. The acetylation of PEG favored the stability of the system and an increase in the zeta potential from ?14.83 to ?25.54 mV was observed. Although encapsulation efficiency values between 30.14 and 39.48% were found, the enhanced benznidazole dissolution profile by microparticles enables the use of lower drug concentrations. This fact can be proven by the increased trypanocidal effect of benznidazole when encapsulated in BP3 microparticles. Finally, the high selectivity of the formulations for trypanocidal action guarantees their safety as an alternative for the treatment of the Chagas disease.

ABSTRACT The excessive sun exposure, coupled with lack of sun protection represents one of the biggest risks to the occurrence of skin cancer and photoaging. Recent strategies for photoprotection have included the incorporation of natural antioxidant and anti-inflammatory compounds, into sunscreens, and the oral administration of natural antioxidant extracts. In this work, we use Brazilian red propolis extract because its antioxidant and anti-inflammatory activities. The aim of this work was to evaluate the sun protection factor and antioxidant activity of different hydroalcoholic extracts of red propolis (70% and 75%) prepared from lyophilized red propolis at room and high temperatures. The sun protection factor in vitro was determined by a spectrophotometric method developed by Mansur. The hydroalcoholic extracts of red propolis incorporated with Filter UVA-UVB 5% Gel Permulem TR-1 presented absorption in the UVB region. Also, the in vitro capacity of the hydroalcoholic extracts of red propolis to increase photoprotective activity of Filter UVA-UVB 5% Gel was evaluated. The hydroalcoholic extracts of red propolis incorporated presented higher values of sun protection factor and showed synergism in the photoprotective activity of Filter UVA-UVB 5% Gel Permulem TR-1. The antioxidant activity and sun protection factor are correlated with total phenolics content of the extracts and the hydroalcoholic extract of red propolis 75% at room temperature was choosen. The formulation developed with Filter UVA-UVB 5% Gel Permulem TR-1 with this hydroalcoholic extract of red propolis showed safe to be applied on the skin according HET-CAM test. Suggests indication of hydroalcoholic extract of red propolis (75% – room temperature) associated to photoprotective formulations for use in photoprotective products.