Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Bioorg Chem ; 138: 106614, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37216893

RESUMO

The inflammatory response is a vital mechanism for repairing damage induced by aberrant health states or external insults; however, persistent activation can be linked to numerous chronic diseases. The nuclear factor kappa ß (NF-κB) inflammatory pathway and its associated mediators have emerged as critical targets for therapeutic interventions aimed at modulating inflammation, necessitating ongoing drug development. Previous studies have reported the inhibitory effect of a hydroethanol extract derived from Parinari excelsa Sabine (Chrysobalanaceae) on tumour necrosis factor-alpha (TNF-α), but the phytoconstituents and mechanisms of action remained elusive. The primary objective of this study was to elucidate the phytochemical composition of P. excelsa stem bark and its role in the mechanisms underpinning its biological activity. Two compounds were detected via HPLC-DAD-ESI(Ion Trap)-MS2 analysis. The predominant compound was isolated and identified as naringenin-8-sulphonate (1), while the identity of the second compound (compound 2) could not be determined. Both compound 1 and the extract were assessed for anti-inflammatory properties using a cell-based inflammation model, in which THP-1-derived macrophages were stimulated with LPS to examine the treatments' effects on various stages of the NF-κB pathway. Compound 1, whose biological activity is reported here for the first time, demonstrated inhibition of NF-κB activity, reduction in interleukin 6 (IL-6), TNF-α, and interleukin 1 beta (IL-1ß) production, as well as a decrease in p65 nuclear translocation in THP-1 cells, thus highlighting the potential role of sulphur substituents in the activity of naringenin (3). To explore the influence of sulphation on the anti-inflammatory properties of naringenin derivatives, we synthesized naringenin-4'-O-sulphate (4) and naringenin-7-O-sulphate (5) and evaluated their anti-inflammatory effects. Naringenin derivatives 4 and 5 did not display potent anti-inflammatory activities; however, compound 4 reduced IL-1ß production, and compound 5 diminished p65 translocation, with both exhibiting the capacity to inhibit TNF-α and IL-6 production. Collectively, the findings demonstrated that the P. excelsa extract was more efficacious than all tested compounds, while providing insights into the role of sulphation in the anti-inflammatory activity of naringenin derivatives.


Assuntos
Chrysobalanaceae , NF-kappa B , Humanos , NF-kappa B/metabolismo , Interleucina-6/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Chrysobalanaceae/metabolismo , Casca de Planta/metabolismo , Anti-Inflamatórios/uso terapêutico , Inflamação/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Lipopolissacarídeos/farmacologia
2.
Food Chem ; 313: 126117, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31951881

RESUMO

Licania tomentosa is a Brazilian plant species that produces edible fruits, yet there is little information available concerning their nutritional and/or bioactive composition. This study aimed to evaluate the nutritional and polyphenol composition of L. tomentosa fruits (pulp and seeds) and measure antioxidant activity in ethanolic extracts.The pulp and seeds were excellent sources of fiber (25.62%-41.70%) as well as minerals and vitamins. L. tomentosa contained no lectins or protease inhibitors (chymotrysin and trypsin) and 12 polyphenol compounds were identified in the seed extracts with a predominance of flavonoids. The seeds also presented antioxidant activities using the DPPH (SC5010.30-15.87 µg/mL), TBARS (IC50 18.46-20.84 µg/mL), and FRAP (RC50 0.203-0.309 µg/mL) assays. Due to its nutrient and antioxidant content, L. tomentosa may be used for food applications.


Assuntos
Antioxidantes/química , Chrysobalanaceae/química , Valor Nutritivo , Extratos Vegetais/química , Brasil , Cromatografia Líquida de Alta Pressão , Chrysobalanaceae/metabolismo , Flavonoides/química , Farinha/análise , Frutas/química , Frutas/metabolismo , Polifenóis/análise , Polifenóis/química , Inibidores de Proteases/análise , Inibidores de Proteases/química , Sementes/química , Sementes/metabolismo , Espectrometria de Massas por Ionização por Electrospray
3.
Anal Chem ; 91(16): 10413-10423, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31313915

RESUMO

Flavonoids represent an important class of natural products with a central role in plant physiology and human health. Their accurate annotation using untargeted mass spectrometry analysis still relies on differentiating similar chemical scaffolds through spectral matching to reference library spectra. In this work, we combined molecular network analysis with rules for fragment reactions and chemotaxonomy to enhance the annotation of similar flavonoid glyconjugates. Molecular network topology progressively propagated the flavonoid chemical functionalization according to collision-induced dissociation (CID) reactions, as the following chemical attributes: aglycone nature, saccharide type and number, and presence of methoxy substituents. This structure-based distribution across the spectral networks revealed the chemical composition of flavonoids across intra- and interspecies and guided the putatively assignment of 64 isomers and isobars in the Chrysobalanaceae plant species, most of which are not accurately annotated by automated untargeted MS2 matching. These proof of concept results demonstrate how molecular networking progressively grouped structurally related molecules according to their product ion scans, abundances, and ratios. The approach can be extrapolated to other classes of metabolites sharing similar structures and diagnostic fragments from tandem mass spectrometry.


Assuntos
Chrysobalanaceae/química , Flavonoides/isolamento & purificação , Glicoconjugados/isolamento & purificação , Glicosídeos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Chrysobalanaceae/metabolismo , Flavonoides/química , Flavonoides/classificação , Glicoconjugados/química , Glicoconjugados/classificação , Glicosídeos/química , Glicosídeos/classificação , Glicosilação , Espectrometria de Massas por Ionização por Electrospray
4.
Anal Chem ; 89(19): 10537-10546, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28850221

RESUMO

Online two-dimensional (2D) comprehensive liquid chromatography (LC × LC) has become increasingly popular. Most LC × LC separations employ one or more detectors at the outlet of the second dimension, 2D, with very short runs to avoid undersampling. We used six detectors, including dual parallel mass spectrometry (LC1MS2), for detection of the first dimension, 1D. We made an argentation (silver-ion) UHPLC column from a strong cation exchange column for 2D, coupled with UV and LC1MS2 detection. LC1MS2 in 1D combined with LC1MS2 in 2D, plus five other detectors, constituted LC2MS4 in a comprehensive LC1MS2 × LC1MS2 2D-LC separation. Electrospray ionization (ESI) high resolution accurate mass (HRAM) mass spectrometry (MS) and atmospheric pressure chemical ionization (APCI) MS were used in parallel for 1D detection, while atmospheric pressure photoionization (APPI) MS and ESI-MS were used for detection of 2D. The LC1MS2 used for 1D allowed quantification of triacylglycerol (TAG) molecular species of Parinari curatellifolia and other seed oils, while the 2D allowed isomers of TAG containing 18:3 fatty acyl chains as well as TAG regioisomers to be separated and identified. The LC1MS2 in 1D allowed identification of oxo-TAG species by HRAM MS and quantification of 806.3 ± 1.3 and 1101 ± 22 µg/g of α- and γ- tocopherols, respectively, in P. curatellifolia by APCI-MS. It is now feasible to use silver-ion UHPLC as the 2D separation in LC × LC and to use multiple mass spectrometers across both dimensions to perform conventional quantitative analysis and to take advantage of the newest LC × LC separation technology to identify isomers that are otherwise difficult to separate.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Chrysobalanaceae/metabolismo , Óleos de Plantas/química , Espectrometria de Massas por Ionização por Electrospray , Triglicerídeos/análise , Chrysobalanaceae/química , Sementes/química , Sementes/metabolismo , Estereoisomerismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA