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Recentemente ficou demonstrado que sedimentos eolicamente transportados perdem a maior parte de sua termoluminescência (TL) geológica quando expostos à luz solar (WINTLE e HUNTLEY, 1980; WINTLE, 1981; SINGHVI et al., 1982). Esta propriedade foi utilizada na tentativa de obterem-se idades de sistemas de dunas e de depósitos marinhos do quaternário costeiro do Rio Grande do Sul. Os resultados preliminares apresentados neste trabalho revelam que datações de areias quartzosas, oriundas destes tipos de depósitos, por termoluminescência, são viáveis, abrangendo o intervalo de tempo compreendido entre o presente e, pelo menos, 50.000 anos, sendo este tempo possivelmente extensível a mais de 100.000 anos.

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Bacterial and viral infections are serious public health issue. Therefore, this study aimed to evaluate the antibacterial, antibiofilm and antiviral potential of the Brazilian Red Propolis (BRP) crude hydroalcoholic extract, fractions, and isolated compounds, as well as their in vivo toxicity. The antibacterial activity was evaluated by determining the Minimum Inhibitory Concentration and the antibiofilm activity by determining the Minimum Inhibitory Concentration of Biofilm (MICB50). The viable bacteria count (Log10 UFC/mL) was also obtained. The antiviral assays were performed by infecting BHK-21 cells with Chikungunya (CHIKV) nanoluc. The toxicity of the BRP was evaluated in the Caenorhabditis elegans animal model. The MIC values for the crude hydroalcoholic extract sample ranged from 3.12 to 100 μg/mL, while fractions and isolated compounds the MIC values ranged from 1.56 to 400 μg/mL.The BRP crude hydroalcoholic extract, oblongifolin B, and gutiferone E presented MICB50 values ranging from 1.56 to 100 μg/mL against monospecies and multispecies biofilms. Neovestitol and vestitol inhibited CHIKV infection by 93.5 and 96.7%, respectively. The tests to evaluate toxicity in C. elegans demonstrated that the BRP was not toxic below the concentrations 750 μg/mL. The results constitute an alternative approach for treating various infectious diseases.