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Agro-industrial residues have attracted attention for their applications in the field of biodegradable packaging. Recently, our research group has developed onion-based films with promising properties for this type of application due to their non-toxicity, biocompatibility and biodegradability. Therefore, in this study, we investigated the effect of Laponite clay concentration on the physicochemical and antioxidant properties of the onion-based films, which were prepared by a casting method. The XRD and FTIR data confirm the presence of the mineral clay in the onion-based films. These findings are consistent with those obtained from FE-SEM analysis, which revealed the presence of typical Laponite grains. In terms of wettability, the results show that the clay decreases the hydrophilic character of the material but slightly increases the water vapor permeation. Optical characterization revealed that the materials exhibited zero transmittance in the UV region and increased opacity in the visible region for composites containing 5% and 10% Laponite. Furthermore, the antioxidant test demonstrated higher antioxidant potential in the composites compared to the pure films. Consequently, these results suggest that the formation of Laponite and onion composites could be an essential strategy for developing natural polymers in the field of food contact packaging.
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A bioassay-guided study aiming at identifying inhibitors of the glycation process on the leaves of Ocotea paranapiacabensis afforded four benzylisoquinoline alkaloids (1-4), with 1 and 2 identified as new naturals products, while 3 and 4 were previously described in the literature, with 3 being identified as magnocurarine. Purification was performed by column chromatography and high-performance liquid chromatography. The structures of the isolated compounds were elucidated by spectroscopic methods including UV, NMR, and HRMS. The process of skin aging has been recently associated with advanced glycation end products (AGEs), and strategies inhibiting their formation have been addressed by pharmaceutical companies for the development of novel antiaging compounds. Alkaloids 1-4 were evaluated for their potential to inhibit AGE formation and showed inhibition of 62.9%, 83.3%, 26.1%, and 98.2% (150 µM), respectively. The antiaging potential of compounds 1 and 4 were evaluated with a reconstructed human skin model in vitro, and results showed a decrease in dermis contraction (8.7% and 4.2% respectively for 1 and 4) when compared to the glycated control (57.4%). Additionally, absorption, distribution, metabolism, and excretion (ADME) and toxicity properties were predicted using in silico methods, and the results were considered significantly promising for alkaloids 1 and 4 to continue the development of these alkaloids with skincare properties.
Assuntos
Alcaloides/farmacologia , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Ocotea/química , Envelhecimento da Pele/efeitos dos fármacos , Glicosilação , Humanos , Técnicas In Vitro , Estrutura Molecular , Compostos Fitoquímicos/farmacologia , Folhas de Planta/químicaRESUMO
INTRODUCTION: Byrsonima species have been used in the treatment of gastrointestinal and gynecological inflammations, skin infections and snakebites. Based on their biological activities, it is important to study other organisms from this genus and to identify their metabolites. OBJECTIVES: To determine the metabolic fingerprinting of methanol and ethyl acetate extracts of four Byrsonima species (B. intermedia, B. coccolobifolia, B. verbascifolia and B. sericea) by HPLC-DAD-ESI-MS/MS and evaluate their in vitro antioxidant, anti-glycation, anti-inflammatory and cytotoxic activities. MATERIALS AND METHODS: Antioxidant activity was determined by DPPHË, ABTSË+ and ROOË scavenging assays. Anti-glycation activity was evaluated by the ability to inhibit the formation of advanced glycation endproducts (AGEs). Anti-inflammatory activity was evaluated using a murine macrophage cell line (RAW 264-7) in the presence of lipopolysaccharide (LPS). Tumour necrosis factor alpha (TNF-α) and nitrite (NO2- ) production were measured by ELISA and the Griess reaction, respectively. The compounds present in the extracts were tentatively identified by HPLC-DAD-ESI-MS/MS. RESULTS: The evaluation of the biological activities showed the potential of the extracts. The activities were assigned to the presence of glycoside flavonoids mainly derived from quercetin, quinic acid derivatives, gallic acid derivatives, galloylquinic acids and proanthocyanidins. Two isomers of sinapic acid-O-hexoside were described for the first time in a Byrsonima species. CONCLUSION: This research contributes to the study of the genus, it is the first report of the chemical composition of B. sericea and demonstrates the importance of the dereplication process, allowing the identification of known compounds without time-consuming procedures. Copyright © 2017 John Wiley & Sons, Ltd.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Malpighiaceae/química , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Produtos Finais de Glicação Avançada/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Extratos Vegetais/farmacologia , Células RAW 264.7RESUMO
In this work, scaffolds based on poly(hydroxybutyrate) (PHB) and micronized bacterial cellulose (BC) were produced through 3D printing. Filaments for the printing were obtained by varying the percentage of micronized BC (0.25, 0.50, 1.00, and 2.00%) inserted in relation to the PHB matrix. Despite the varying concentrations of BC, the biocomposite filaments predominantly contained PHB functional groups, as Fourier transform infrared spectroscopy (FTIR) demonstrated. Thermogravimetric analyses (i.e., TG and DTG) of the filaments showed that the peak temperature (Tpeak) of PHB degradation decreased as the concentration of BC increased, with the lowest being 248 °C, referring to the biocomposite filament PHB/2.0% BC, which has the highest concentration of BC. Although there was a variation in the thermal behavior of the filaments, it was not significant enough to make printing impossible, considering that the PHB melting temperature was 170 °C. Biological assays indicated the non-cytotoxicity of scaffolds and the provision of cell anchorage sites. The results obtained in this research open up new paths for the application of this innovation in tissue engineering.
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Eight phenolic compounds were isolated from Eugenia pyriformis leaves fraction by semi-preparative HPLC and characterized by Nuclear Magnetic Resonance (NMR) and mass spectrometry (ESI-MS). Five compounds were isolated and identified for the first time in E. pyriformis species, while this is the first report of the accumulation of isoquercitrin, quercitrin, and the aglycone quercetin in its leaves. E. pyriformis leaves and fruits extracts, as well as the compounds isolated from the leaves most active fraction, were evaluated for their antiglycation and antioxidant activities. The mixture of myricetin-3-O-(2â³-O-galloyl)-α-L-rhamnoside and myricetin-3-O-(4â³-O-galloyl)-α-L-rhamnoside showed the highest antiglycation activity. These results suggest that this species is a promising source of bioactive compounds. Further studies to investigate the inhibition of the glycation process in vivo are necessary to evaluate its use in the treatment and/or prevention of advanced glycation end-products (AGEs)-associated diseases.
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Eugenia , Antioxidantes/química , Eugenia/química , Frutas/química , Extratos Vegetais/química , Folhas de Planta/químicaRESUMO
The intrinsic value of biodiversity extends beyond species diversity, genetic heritage, ecosystem variability and ecological services, such as climate regulation, water quality, nutrient cycling and the provision of reproductive habitats it is also an inexhaustible source of molecules and products beneficial to human well-being. To uncover the chemistry of Brazilian natural products, the Nuclei of Bioassays, Ecophysiology and Biosynthesis of Natural Products Database (NuBBEDB) was created as the first natural product library from Brazilian biodiversity. Since its launch in 2013, the NuBBEDB has proven to be an important resource for new drug design and dereplication studies. Consequently, continuous efforts have been made to expand its contents and include a greater diversity of natural sources to establish it as a comprehensive compendium of available biogeochemical information about Brazilian biodiversity. The content in the NuBBEDB is freely accessible online (https://nubbe.iq.unesp.br/portal/nubbedb.html) and provides validated multidisciplinary information, chemical descriptors, species sources, geographic locations, spectroscopic data (NMR) and pharmacological properties. Herein, we report the latest advancements concerning the interface, content and functionality of the NuBBEDB. We also present a preliminary study on the current profile of the compounds present in Brazilian territory.