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Flvia A. R. dos Santos Jadriane A. Xavier Felipe C. da Silva J. P. Jose Merlin Marília O. F. Goulart H. P. Vasantha Rupasinghe 《Molecules (Basel, Switzerland)》2022,27(13)
The objective of this work was to investigate the antidiabetic, antiglycation, and antioxidant potentials of ethanolic extract of seeds of Brazilian Passiflora edulis fruits (PESE), a major by-product of the juice industry, and piceatannol (PIC), one of the main phytochemicals of PESE. PESE, PIC, and acarbose (ACB) exhibited IC50 for alpha-amylase, 32.1 ± 2.7, 85.4 ± 0.7, and 0.4 ± 0.1 µg/mL, respectively, and IC50 for alpha-glucosidase, 76.2 ± 1.9, 20.4 ± 7.6, and 252 ± 4.5 µg/mL, respectively. The IC50 of PESE, PIC, and sitagliptin (STG) for dipeptidyl-peptidase-4 (DPP-4) was 71.1 ± 2.6, 1137 ± 120, and 0.005 ± 0.001 µg/mL, respectively. PESE and PIC inhibited the formation of advanced glycation end-products (AGE) with IC50 of 366 ± 1.9 and 360 ± 9.1 µg/mL for the initial stage and 51.5 ± 1.4 and 67.4 ± 4.6 µg/mL for the intermediate stage of glycation, respectively. Additionally, PESE and PIC inhibited the formation of β-amyloid fibrils in vitro up to 100%. IC50 values for 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•) scavenging activity of PESE and PIC were 20.4 ± 2.1, and 6.3 ± 1.3 µg/mL, respectively. IC50 values for scavenging hypochlorous acid (HOCl) were similar in PESE, PIC, and quercetin (QCT) with values of 1.7 ± 0.3, 1.2 ± 0.5, and 1.9 ± 0.3 µg/mL, respectively. PESE had no cytotoxicity to the human normal bronchial epithelial (BEAS-2B), and alpha mouse liver (AML-12) cells up to 100 and 50 µg/mL, respectively. However, 10 µg/mL of the extract was cytotoxic to non-malignant breast epithelial cells (MCF-10A). PESE and PIC were found to be capable of protecting cultured human cells from the oxidative stress caused by the carcinogen NNKOAc at 100 µM. The in vitro evidence of the inhibition of alpha-amylase, alpha-glucosidase, and DPP-4 enzymes as well as antioxidant and antiglycation activities, warrants further investigation of the antidiabetic potential of P. edulis seeds and PIC. 相似文献
413.
Flavia Suzany Ferreira dos Santos Jos Filipe Bacalhau Rodrigues Milena Costa da Silva Maria Eduarda Vasconcelos Barreto Henrique Nunes da Silva Sudina Maria de Lima Silva Marcus Vinicius Lia Fook 《Molecules (Basel, Switzerland)》2023,28(1)
This study aimed to achieve bioactivity on the PEEK surface using piranha solution through a lower functionalization time. For this purpose, the functionalization occurred with piranha solution and 98% sulfuric acid in the proportions of 1:2, 1:1, and 2:1 at periods of 30, 60, and 90 s. The samples treated for longer times at higher concentrations registered the characteristic spectroscopy band associated with sulfonation. Additionally, both chemical treatments allowed the opening of the aromatic ring, increasing the number of functional groups available and making the surface more hydrophilic. The piranha solution treatments with higher concentrations and longer times promoted greater heterogeneity in the surface pores, which affected the roughness of untreated PEEK. Furthermore, the treatments induced calcium deposition on the surface during immersion in SBF fluid. In conclusion, the proposed chemical modifications using sulfuric acid SPEEK 90 and, especially, the piranha solution PEEK-PS 2:1-90, were demonstrated to be promising in promoting the rapid bioactivation of PEEK-based implants. 相似文献
414.
Filipe Camarneiro Juanita Bocquel Juan Gallo Manuel Bañobre-López Kirstine Berg-Sørensen Ulrik Lund Andersen Alexander Huck Jana B. Nieder 《Particle & Particle Systems Characterization》2021,38(8):2100011
A modified diamond–photonics based metrology is proposed to explore the magnetic fields created by agglomerates of magnetic nanoparticles (MNPs). MNPs are promising for environmental and medical applications; those proposed for cancer magnetic hyperthermia treatments are small superparamagnetic <20 nm iron oxide particles. Inside cells, they assemble in larger MNP agglomerates, reaching cross-sections of several micrometers. Here, these conditions are reproduced and MNP agglomerates immobilized. Optically detected magnetic resonance (ODMR) signals recorded without a bias field in a confocal microscope and scanning across a homogenous shallow layer of fluorescent nitrogen-vacancy centers in a bulk diamond sample placed in direct contact with the MNP agglomerates are used to determine magnetic fields with a spatial resolution of 500 nm in a lateral direction. This spatial resolution allows determining magnetic field maps around individual MNP agglomerates, for which magnetic fields with strengths ranging from 0.03 mT to maximal 1.2 mT in the direct vicinity of the agglomerates and with detectable fields up to 5 µm away from the agglomerates, are determined. Based on the findings, a pathway to non-invasively study the micro/nano topology of MNP agglomerates is proposed. 相似文献
415.
416.
Filipe S. F. Jacinto Leonardo J. A. Siqueira Wagner A. Alves 《Journal of Raman spectroscopy : JRS》2009,40(11):1585-1590
Raman and IR experiments have been carried out on formamide (FA) and pyridine (Py) mixtures at different compositions. The appearance of a new Raman band at 996 cm−1 (ν1 region of Py), whose intensity depends on the FA concentration, is assigned to an FA:Py adduct and this result is in excellent agreement with those of other authors who employed noisy light‐based coherent Raman scattering spectroscopy (I(2) CARS). Another band at 1587 cm−1 (ν8 region of Py) has been observed for the first time by using Raman and IR spectroscopies. Its intensity shows the same dependence on the FA concentration and this fact allows us to also attribute it to an FA:Py adduct. The good relationship between the Raman and IR data demonstrates the potential of the vibrational spectroscopy for this kind of study. Owing to higher absolute Raman scattering cross section, the ν1 region of Py has been chosen for the quantitative analysis and a stoichiometry of 1:1 FA:Py is reported. The experimental data are very well supported by the density functional theory (DFT) calculation, which was employed for the first time to the present system. Furthermore, the actual investigation shows an excellent agreement with those reported from computational calculations for similar systems. A comparison with our previous studies confirms that the solvent dielectric constant determines the stoichiometry of a given Lewis acid–base adduct in the infinite dilution limit. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
417.
418.
Jules Bouffard Filipe Coelho Dr. Naomi Sakai Prof. Stefan Matile 《Angewandte Chemie (International ed. in English)》2023,62(51):e202313931
In this study, we introduce phosphorus, a pnictogen, as an exchange center for dynamic covalent chemistry. Cascade exchange of neutral phosphorotri- and -tetrathioates with thiolates is demonstrated in organic solvents, aqueous micellar systems, and in living cells. Exchange rates increase with the pH value, electrophilicity of the exchange center, and nucleophilicity of the exchangers. Molecular walking of the dynamic phosphorus center along Hammett gradients is simulated by the sequential addition of thiolate exchangers. Compared to phosphorotrithioates, tetrathioates are better electrophiles with higher exchange rates. Dynamic phosphorotri- and -tetrathioates are non-toxic to HeLa Kyoto cells and participate in the dynamic networks that account for thiol-mediated uptake into living cells. 相似文献