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A natural product isolated from Brazilian plant species Baccharis retusa (Asteraceae), 15β-senecioyloxi-ent-kaurenoic acid (1), demonstrated activity against trypomastigotes of the parasite Trypanosoma cruzi but it was inactive against intracellular forms. In the present work, compound 1a, a methyl ester derivative of 1, exhibited activity against intracellular amastigotes (EC 50  = 11.8 μM), similar to that determined by the standard drug benznidazol (EC 50  = 16.2 μM) and no toxicity against NCTC cells (CC 50  > 200 μM). Based on this selectivity, compound 1a was incorporated into Langmuir monolayers of three lipids, DPPC, DPPE, and DPPS, to characterize the interaction of the compound with each lipid as model for cell membranes. For that, we used tensiometry, surface potential measurements, and infrared spectroscopy. Our results showed that incorporating the drug into DPPC monolayers significantly altered the physicochemical properties, resulting in more condensed monolayers. In contrast, the incorporation of the drug into DPPE and DPPS monolayers led to their expansion. The effects on DPPC were more pronounced than on the other lipids, inducing a viscoelastic monolayer with lower alignment of the alkyl chains, as observed through surface potential measurements and infrared spectroscopy. These changes indicate a more cohesive DPPC monolayer upon drug incorporation, forming domains in a strip shape. We believe these results contribute to understanding the interaction between 1a and lipid interfaces, especially those involved in biological interactions with amastigotes of parasite T. cruzi., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Banisteriopsis argyrophylla belongs to the Malpighiaceae family, which is a species from Cerrado, also known as "cipó-prata" or "cipó-folha-de-prata." Several species of this family present biological potential. This work reports the chemical identification of the ethanol extract (EE) and its fractions from B. argyrophylla leaves and shows the analysis of the antioxidant activity and inhibitory effects on activities of α-amylase, α-glucosidase and lipase, and non-enzymatic glycation. The ethyl acetate fraction (EAF) and n-butanol fraction (BF) showed antioxidant activity, with IC 50 values of 4.1 ± 0.1 and 4.8 ± 0.1 μg mL -1 , respectively, by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, and IC 50 values of 6046.3 ± 174.2 and 6264.2 ± 32.2 µmol Trolox eq g -1 by the oxygen radical absorbance capacity (ORAC) method. Furthermore, the DPPH method with these fractions presented electroactive species with antioxidant potential, as shown by the differential pulse voltammetry (DPV) method. The inhibitory effects of the EAF and BF were demonstrated by the following results: IC 50 of 5.1 ± 0.3 and 2.5 ± 0.2 μg mL -1 for α-amylase, IC 50 of 1093.5 ± 26.0 and 1250.8 ± 21.9 μg mL -1 for α-glucosidase, IC 50 of 8.3 ± 4.1 and 4.4 ± 1.0 μg mL -1 for lipase, and IC 50 of 1.3 ± 0.1 and 0.9 ± 0.1 μg mL -1 for glycation. Some bioactive compounds were identified by (-)-ESI-MS/MS, such as catechin, procyanidins, glycosylated flavonoids, kaempferol, and megastigmane glucosides. The antidiabetic activity of B.argyrophylla has been reported for the first time., (Copyright © 2020 Elsevier Inc. All rights reserved.)