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1.
Bioorg Chem ; 138: 106614, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37216893

RESUMEN

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.


Asunto(s)
Chrysobalanaceae , FN-kappa B , Humanos , FN-kappa B/metabolismo , Interleucina-6/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Chrysobalanaceae/metabolismo , Corteza de la Planta/metabolismo , Antiinflamatorios/uso terapéutico , Inflamación/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Lipopolisacáridos/farmacología
2.
Anal Chem ; 91(16): 10413-10423, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31313915

RESUMEN

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.


Asunto(s)
Chrysobalanaceae/química , Flavonoides/aislamiento & purificación , Glicoconjugados/aislamiento & purificación , Glicósidos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Chrysobalanaceae/metabolismo , Flavonoides/química , Flavonoides/clasificación , Glicoconjugados/química , Glicoconjugados/clasificación , Glicósidos/química , Glicósidos/clasificación , Glicosilación , Espectrometría de Masa por Ionización de Electrospray
3.
Anal Chem ; 89(19): 10537-10546, 2017 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-28850221

RESUMEN

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.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Chrysobalanaceae/metabolismo , Aceites de Plantas/química , Espectrometría de Masa por Ionización de Electrospray , Triglicéridos/análisis , Chrysobalanaceae/química , Semillas/química , Semillas/metabolismo , Estereoisomerismo
4.
Food Chem ; 313: 126117, 2020 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31951881

RESUMEN

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.


Asunto(s)
Antioxidantes/química , Chrysobalanaceae/química , Valor Nutritivo , Extractos Vegetales/química , Brasil , Cromatografía Líquida de Alta Presión , Chrysobalanaceae/metabolismo , Flavonoides/química , Harina/análisis , Frutas/química , Frutas/metabolismo , Polifenoles/análisis , Polifenoles/química , Inhibidores de Proteasas/análisis , Inhibidores de Proteasas/química , Semillas/química , Semillas/metabolismo , Espectrometría de Masa por Ionización de Electrospray
5.
Int J Biol Macromol ; 140: 294-302, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31422188

RESUMEN

Several plants have been studied for their medicinal properties, especially concerning the management of chronic diseases, such as diabetes, aiming at a more accessible form of treatment. In this context, the aim of this study was to characterize plant proteins used in folk medicine as hypoglycemic agents for the treatment of diabetes, namely "abajerú" (Chrysobalanus icaco) and "cow's paw" (Bauhinia forficata and Bauhinia variegata). The species were differentiated by proteome characterization. Proteins were in-solution digested using trypsin by the filter-assisted sample preparation (FASP) method. Peptides were then analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) for protein characterization. In total, 131 proteins were identified. The main biological functions of these proteins were cellular respiration, transport, metabolism and photosynthesis. Insulin-like proteins were not detected, but proteins involved in controlling glucose levels were. The results are of value in the proteomic characterization of phytotherapeutic plants, and may serve as baseline for the assessed species in Brazil, where a lack of knowledge in this regard is observed.


Asunto(s)
Bauhinia/metabolismo , Chrysobalanaceae/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Hipoglucemiantes/farmacología , Extractos Vegetales/farmacología , Proteoma , Brasil , Cromatografía Liquida , Geografía , Hipoglucemiantes/química , Medicina Tradicional , Extractos Vegetales/química , Hojas de la Planta/metabolismo , Plantas Medicinales , Proteómica , Espectrometría de Masas en Tándem
6.
New Phytol ; 170(1): 99-105, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16539607

RESUMEN

Most research analyzing nonstructural carbohydrate (NSC) concentrations on resprouter species in fire-controlled ecosystems has concentrated on how NSC concentrations recover immediately after fire. However, we know little of the effect of long periods without fire on NSC concentrations. In order to assess the effect of different periods of time-since-fire on resprouter species, we studied carbohydrate concentrations (total [NSC], soluble sugars [SS] and nonsoluble sugars [NSS]) in five resprouting species with contrasting trends of abundance across a chronosequence of time-since-fire (0.5-40 yr) in Florida. Carbohydrate concentrations were highest in species with specialized reserve organs. [SS] was mainly explained by factors related to plant size, whereas time-since-fire was the main factor explaining [NSS]. Changes in [NSS] and [NSC] were correlated with the time-since-fire abundance patterns. Variation in [NSS] carbohydrates can be related to the structural development of vegetation, with only those species capable of accessing full light able to accumulate carbohydrates, whereas subordinate plants show reductions in the [NSS] carbohydrate fractions. In areas with long intervals between fires, this carbohydrate reduction could affect subsequent postfire resprouting vigour, although this remains to be confirmed.


Asunto(s)
Metabolismo de los Hidratos de Carbono/fisiología , Incendios , Magnoliopsida/metabolismo , Asteraceae/metabolismo , Chrysobalanaceae/metabolismo , Ecosistema , Florida , Modelos Biológicos , Modelos Estadísticos , Quercus/metabolismo , Smilax/metabolismo , Vaccinium/metabolismo
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