The interaction of small molecules with DNA has been quite important, since this biomolecule is currently the major target for a wide range of drugs in clinical use or advanced clinical research phase. Thus, the present work aimed to assess the interaction process between the bioactive compound 11a-N-tosyl-5-carba-pterocarpan, (LQB-223), that presents antitumor activity, with DNA, employing spectroscopic techniques, electrophoresis, viscosity and theoretical studies. Through UV-vis and molecular fluorescence spectroscopy, it was possible to infer that the preferential quenching mechanism was static, characterized by non-fluorescent supramolecular complex formation between the LQB-223 and DNA. The binding constant was 1.94∙10Lmol (30°C) and, according to the thermodynamic parameters, the main forces involved in the interaction process are hydrophobic. Potassium iodide assay, competition with ethidium bromide, fluorescence contact energy transfer and melting temperature profile of DNA were employed to evaluate the binding mode. Except for KI assay, all results obtained indicated minor groove as the preferential binding mode of LQB-223 to DNA. These observations were supported by ionic strength assay, viscosity and molecular dynamics and docking studies. Finally, electrophoresis analysis demonstrated that the interaction does not promote DNA fragmentation, but it leads to variation in the migration profile after increasing the ligand concentration.

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The main objectives of this study were to develop and characterize hydrophilic polymeric membranes impregnated with poly-lactic acid (PLA) nanoparticles (NPs) combined with red propolis (RP). Ultrasonic-assisted extraction was used to obtain 30% (w/v) red propolis hydroalcoholic extract (RPE). The NPs (75,000 g mol−1) alone and incorporated with RP (NPRP) were obtained using the solvent emulsification and diffusion technique. Biopolymeric hydrogel membranes (MNPRP) were obtained using carboxymethylcellulose (CMC) and NPRP. Their characterization was performed using thermal analysis, Fourier transform infrared (FTIR), total phenols (TPC) and flavonoids contents (TFC), and antioxidant activity through the radical scavenging assay with 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and Ferric reducing antioxidant power (FRAP). The identification and quantification of significant RP markers were performed through UPLC-DAD. The NPs were evaluated for particle size, polydispersity index, and zeta potential. The TPC for RPE, NPRP, and MNPRP was 240.3 ± 3.4, 191.7 ± 0.3, and 183.4 ± 2.1 mg EGA g−1, while for TFC, the value was 37.8 ± 0.9, 35 ± 3.9, and 26.8 ± 1.9 mg EQ g−1, respectively. Relevant antioxidant activity was also observed by FRAP, with 1400.2 (RPE), 1294.2 (NPRP), and 696.2 µmol Fe2+ g−1 (MNPRP). The primary markers of RP were liquiritigenin, isoliquiritigenin, and formononetin. The particle sizes were 194.1 (NPs) and 361.2 nm (NPRP), with an encapsulation efficiency of 85.4%. Thermal analysis revealed high thermal stability for the PLA, nanoparticles, and membranes. The DSC revealed no interaction between the components. FTIR allowed for characterizing the RPE encapsulation in NPRP and CMC for the MNPRP. The membrane loaded with NPRP, fully characterized, has antioxidant capacity and may have application in the treatment of skin wounds.

Plasmodium species are responsible for a high incidence of cases and resistance, even with several approved drugs. Quinoline derivatives are recognized as a source of active compounds, where tafenoquine has been recently approved. Cases of resistance and the indiscriminate use of anti-malarials against COVID-19 have negatively contributed to eradicating this disease. In this context, modifications at 2- or 4-amino positions from the quinoline scaffold or even its metal complexes have shown promising advances in the field, especially against resistant strains, such as 3D7, W2, D10, Dd2, K1 , and FCR-3. In this chapter, we discussed all aspects involving such compounds, presenting their results based on SAR analysis and recent contributions/advances involving this classic scaffold arising from nature.

RESUMO -A traça-das-crucíferas, Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae), é a principal praga de brássicas em todo o mundo, principalmente por sua fácil dispersão, curto ciclo e grande capacidade de desenvolver resistência a inseticidas. Por esse motivo, a adoção de métodos de controle alternativos é importante para a elaboração de um manejo integrado para a espécie. Desta forma, avaliou-se o efeito de extratos aquosos de Aspidosperma macrocarpum Mart. (Apocynaceae) (AM1 = ramos + caule; AM2 = folhas e AM3 = casca do caule) em relação a diferentes fases do estágio larval de P. xylostella. Discos de folhas de couve (Brassica oleracea var. acephala) foram imersas em cada extrato à concentração de 1% (m/v) por 30 segundos, e após secos ao ar livre, foram inoculados com 12 lagartas com 1, 3 e 5 dias após a eclosão (DAE), mais a testemunha. Avaliou-se a foi maior com lagarta de 1 DAE e, à medida que a lagarta se aproximou da formação da pupa (cinco DAE), essa ação inseticida não apresentou efeito. Houve diferença em relação às partes da planta, sendo a AM1 a que apresentou maior percentagem de mortalidade (45,0 %). Palavras-chave:Plutella xylostella, planta inseticida, couve. USE OF AQUEOUS EXTRACTS OF Aspidosperma macrocarpon ON THE DIFFERENT LARVAL STAGES OF DIAMOND MOTHABSTRACT -The diamondback moth, Plutella xylostella (L., 1758) (Lepidoptera: Plutellidae), is the major pest of crucifers worldwide, mainly because of its ease of dispersion, short cycle and high capacity to develop resistance to insecticides. Therefore, the adoption of alternative control methods is important for the development of an integrated management plan for the species. Therefore, the aim of this study was to evaluate the effect of aqueous extracts of Aspidosperma macrocarpum Mart. (Apocynaceae) (AM1 = branches + bark, AM2 = leaves and AM3 = wood bark) for different stages of larval stage of P. xylostella. Discs of leaves of cabbage (Brassica oleracea var. acephala ) were immersed in each extract at a concentration of 1 % (weight / volume) for 30 seconds, and after air -dried , and inoculated with 12 caterpillars of varying days after hatching (1, 3 and 5 days) plus the control, in hatch) as larger percentage mortality occurred in all treatments during this period. But in stage near the pupation, treatment showed the highest percentage of mortality with 45.00% of dead caterpillars.