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1.
Braz J Biol ; 83: e271577, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37466512

RESUMEN

Fungal diseases, especially those that affect the root systems of plants, caused by Rhizoctonia and Macrophomina are limiting factors for achieving high crop yields. Alternatives to controlling fungi with chemical products drive the search for new options for bioactive compounds from plants. Attalea geraensis, a palm tree from the Brazilian Cerrado, is rich in flavonoids with antifungal actions. The objective of this work is to identify the chemical classes present in the ethanolic extract of green leaves of A. geraensis and determine the antifungal potential of the extract against isolates of Macrophomina phaseolina (Tassi) Goid. and Rhizoctonia solani JG Kühn. Phytochemical prospection, flavonoid dereplication, and antifungal activity were carried out of the ethanolic extract of the green leaves of A. geraensis harvested in the Cerrado area of Brazil. Steroids, triterpenes, saponins, and anthraquinones are described here for the first time for the leaves of A. geraensis. The flavonoids quercetin, isorhamnetin, 3,7-dimethylquercetin, quercetin 3-galactoside, 5,7-dihydroxy-2-(4-hydroxy-3-methoxyphenyl)-3-{[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy}-4H-chromen-4-one, rhamnazin 3-galactoside, keioside, and rhamnazin 3-rutinoside were identified. Of these, only quercetin and isorhamnetin had already been identified in the leaves of A. geraensis. The results show a fungistatic potential for the species. The diversity of flavonoids present in the leaves of A. geraensis may be the result of a synergistic action between fungus and plant or there could be an antagonistic effect between flavonoids and the other identified chemical classes.


Asunto(s)
Antifúngicos , Arecaceae , Antifúngicos/farmacología , Antifúngicos/química , Brasil , Arecaceae/química , Quercetina/análisis , Extractos Vegetales/química , Flavonoides/análisis , Etanol/análisis , Etanol/química , Hojas de la Planta/química , Galactósidos/análisis
2.
Glycoconj J ; 40(1): 85-95, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36287345

RESUMEN

The Dalbergieae lectin group encompasses several lectins with significant differences in their carbohydrate specificities and biological properties. The current work reports on the purification and characterization of a GalNAc/Gal-specific lectin from Vataireopsis araroba (Aguiar) Ducke, designated as VaL. The lectin was purified from the seeds in a single step using guar gum affinity chromatography. The lectin migrated as a single band of about 35 kDa on SDS-PAGE and, in native conditions, occurs as a homodimer. The purified lectin is stable at temperatures up to 60 °C and in a pH range from 7 to 8 and requires divalent cations for its activity. Sugar-inhibition assays demonstrate the lectin specificity towards N-acetyl-D-galactosamine, D-galactose and related sugars. Furthermore, glycan array analyses show that VaL interacts preferentially with glycans containing terminal GalNAc/Galß1-4GlcNAc. Biological activity assays were performed using three insect cell lines: CF1 midgut cells from the spruce budworm Choristoneura fumiferana, S2 embryo cells from the fruit fly Drosophila melanogaster, and GutAW midgut cells from the corn earworm Helicoverpa zea. In vitro assays indicated a biostatic effect for VaL on CF1 cells, but not on S2 and GutAW cells. The lectin presented a biostatic effect by reducing the cell growth and inducing cell agglutination, suggesting an interaction with glycans on the cell surface. VaL has been characterized as a galactoside-specific lectin of the Dalbergieae tribe, with sequence similarity to lectins from Vatairea and Arachis.


Asunto(s)
Fabaceae , Lectinas , Animales , Lectinas/metabolismo , Fabaceae/química , Fabaceae/metabolismo , Drosophila melanogaster , Carbohidratos/análisis , Semillas/química , Polisacáridos/metabolismo , Galactósidos/análisis , Galactósidos/metabolismo , Lectinas de Plantas/química
3.
J Am Chem Soc ; 143(28): 10509-10513, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-34236183

RESUMEN

Sequencing glycans is demanding due to their structural diversity. Compared to mammalian glycans, bacterial glycans pose a steeper challenge because they are constructed from a larger pool of monosaccharide building blocks, including pyranose and furanose isomers. Though mammalian glycans incorporate only the pyranose form of galactose (Galp), many pathogens, including Mycobacterium tuberculosis and Klebsiella pneumoniae, contain galactofuranose (Galf) residues in their cell envelope. Thus, glycan sequencing would benefit from methods to distinguish between pyranose and furanose isomers of different anomeric configurations. We used infrared multiple photon dissociation (IRMPD) spectroscopy with mass spectrometry (MS-IR) to differentiate between pyranose- and furanose-linked galactose residues. These targets pose a challenge for MS-IR because the saccharides lack basic groups, and galactofuranose residues are highly flexible. We postulated cationic groups that could complex through hydrogen bonding would offer a solution. Here, we present the first MS-IR analysis of hexose ammonium adducts. We compared their IR fingerprints with those of lithium adducts. We determined the diagnostic MS-IR signatures of the α- and ß-anomers of galactose in furanose and pyranose forms. We also showed these signatures could be applied to disaccharides to assign galactose ring size. Our findings highlight the utility of MS-IR for analyzing the unique substructures that occur in bacterial glycans.


Asunto(s)
Galactósidos/análisis , Conformación de Carbohidratos , Klebsiella pneumoniae/química , Espectrometría de Masas , Mycobacterium tuberculosis/química , Espectrofotometría Infrarroja , Estereoisomerismo
4.
Artículo en Inglés | MEDLINE | ID: mdl-33486218

RESUMEN

The screening and identification of bioactive components, which are effectively resistant to metallo-beta-lactamase (MßL), were studied in the alcohol extract of Schisandra chinensis (Turcz.) Baill. by metalloenzyme-immobilized affinity chromatography. Taking bizinc metalloenzyme beta-lactamase II from Bacillus cereus (Bc II) and monozinc metalloenzyme CphA from aeromonas hydrophila (CphA) as examples, we studied the feasibility of this scheme based on the construction of metalloenzyme-immobilized chromatographic model. It was found that the Bc II- and CphA-immobilized chromatographic column could be used not only to explore the interaction between the MßL and their specific ligands, but also to screen the bioactive components from traditional Chinese medicine. The Bc II-and CphA-immobilized columns were used to screen the bioactive components from the alcohol extract of Schisandra chinensis (Turcz.) Baill. Time-of-flight tandem mass spectrometry analysis and molecular docking revealed that isobutyl 3-O-sulfo-ß-D-galactopyranoside is the effective bioactive components that could bind with metalloenzyme Bc II. It is believed that our current work may provide a methodological reference for screening MßL inhibitors from traditional Chinese medicine.


Asunto(s)
Proteínas Bacterianas/metabolismo , Cefalosporinasa/metabolismo , Descubrimiento de Drogas/métodos , Extractos Vegetales/análisis , Schisandra/química , beta-Lactamasas/metabolismo , Proteínas Bacterianas/química , Cefalosporinasa/química , Cromatografía de Afinidad , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Galactósidos/análisis , Galactósidos/química , Galactósidos/metabolismo , Simulación del Acoplamiento Molecular , Extractos Vegetales/química , Extractos Vegetales/metabolismo , beta-Lactamasas/química
5.
Chem Pharm Bull (Tokyo) ; 69(2): 218-221, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33268666

RESUMEN

A robust ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) technique was proven effective for simultaneous characterization of six flavonoids including quercetin-3-O-beta-galactoside (Q3GAL), quercetin-3-O-beta-glucoside (Q3GLU), quercetin-3-(2-galloylglucoside) (Q3GG), kaempferol-3-O-beta-galactoside (K3GAL), kaempferol-3-O-beta-glucoside (K3GLU), and kaempferol-3-(2-galloylglucoside) (K3GG) in rat eyes. By investigation of corresponding validation parameters (linearity, selectivity, precision, accuracy, matrix effect, extraction recovery, and stability), the method was verified to be within current acceptable criteria. Thereafter, the validated method enabled quantification of the six compounds successful in rat eyes after oral administration of ethanol extract Diospyros kaki (EEDK) at 0, 3, 15, 35, 60, 120 min.


Asunto(s)
Cromatografía Líquida de Alta Presión , Diospyros/química , Ojo/química , Flavonoides/análisis , Extractos Vegetales/química , Espectrometría de Masas en Tándem , Administración Oral , Animales , Diospyros/metabolismo , Ojo/metabolismo , Flavonoides/administración & dosificación , Galactósidos/administración & dosificación , Galactósidos/análisis , Quempferoles/administración & dosificación , Quempferoles/análisis , Masculino , Monosacáridos/administración & dosificación , Monosacáridos/análisis , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Quercetina/administración & dosificación , Quercetina/análogos & derivados , Quercetina/análisis , Ratas
6.
J Nutr Biochem ; 83: 108418, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32592950

RESUMEN

Colorectal cancer (CRC) is the fourth cancer with the most new cases reported in 2018 worldwide. Consumption of fruit and vegetables is a protective factor against the risk of CRC. Beyond this, flavonoids could orchestrate these healthy effects. Apart from containing the typical apple flavonoids, red-fleshed apples also contain anthocyanins, mainly cyanidin-3-O-galactoside (Cy3Gal). Through an azoxymethane rat carcinogenesis model, a study was carried out in order to assess the possible protective effects of apple polyphenols, with special attention to anthocyanins. In addition, apart from negative and positive controls, a group with chemotherapy with 5-fluorouracil (5FU) was included to compare their performance against the output collected from the animal treatments with white-fleshed apple (WF), red-fleshed apple (RF) and Cy3Gal (AE). Although the 5FU group presented the best performance towards aberrant crypt foci (ACF) inhibition (70.1%), rats fed with white-fleshed apples ('Golden Smoothee') were able to achieve 41.3% ACF inhibition, while none of the challenged treatments (WF, RF and AE) suffered mucin depletion in their colonocytes. Expression changes of 17 genes related to CRC were assessed. In detail, the ACF inhibition phenotype detected in 5FU and WF groups could be explained through the expression changes detected in the apoptosis-related genes of Aurka, p53 and Cox2. Moreover, in the apple consumption groups (WF and RF), a reduced protein expression of matrix metalloproteinases with gelatinase activity (MMP-2 and 9) was detected. Overall, our study suggests an effect of apple polyphenols and apple anthocyanin Cy3Gal against colon carcinogenesis, retarding/diminishing the appearance of the precancerous markers studied.


Asunto(s)
Adenocarcinoma/dietoterapia , Neoplasias del Colon/dietoterapia , Malus/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Animales , Antocianinas/análisis , Antocianinas/metabolismo , Azoximetano/efectos adversos , Carcinogénesis , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Flavonoides/análisis , Flavonoides/metabolismo , Frutas/química , Frutas/metabolismo , Galactósidos/análisis , Galactósidos/metabolismo , Humanos , Masculino , Malus/química , Extractos Vegetales/análisis , Extractos Vegetales/metabolismo , Polifenoles/análisis , Polifenoles/metabolismo , Ratas , Ratas Wistar
7.
Molecules ; 25(8)2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32295006

RESUMEN

Acanthopanax sessiliflorus (Rupr. & Maxim.) Seem. (Araliaceae) is one of the most abundant species of genus Acanthopanax. The fruits of A. sessiliflorus are used in traditional medical protocols as an analgesic, tonic, antidiabetic, antihypertensive, anti-inflammatory, antitumor, and immune-stimulating agent. In this work, we carried out a comprehensive investigation into the anthocyanin components in the fruits of A. sessiliflorus. The anthocyanin content in the fresh fruits of A. sessiliflorus was determined by high performance liquid chromatography-diode array detection (HPLC/DAD), and the anthocyanin component was isolated from these using high-speed counter-current chromatography (HSCCC) and elucidated by electro-spray ionization-mass spectrometry (ESI/MS), 1H- and 13C-NMR. Its antioxidant activity was evaluated by ferric-reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH). We found that A. sessiliflorus contained a gross anthocyanin content of 121.35 mg/100 g. HSCCC was successfully used for separation and purification of the primary anthocyanin component, cyanidin 3-xylosyl-galactoside. The antioxidant and radical scavenging tests indicated that cyanidin 3-xylosyl-galactoside is a potent antioxidant.


Asunto(s)
Antocianinas/análisis , Antioxidantes/análisis , Cromatografía Líquida de Alta Presión/métodos , Eleutherococcus/química , Extractos Vegetales/análisis , Antocianinas/química , Compuestos de Bifenilo/química , Cromatografía Líquida de Alta Presión/instrumentación , Frutas/química , Galactósidos/análisis , Galactósidos/química , Espectroscopía de Resonancia Magnética , Picratos/química , Extractos Vegetales/química
8.
Food Chem ; 322: 126767, 2020 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-32330787

RESUMEN

Due to the lack of innovative valorization strategies, berry pomaces are a poorly utilized as a cheap source of valuable nutrients and phytochemicals. An effective biorefining scheme was developed to recover functional components from lingonberry pomace by consecutive supercritical CO2 (SFE-CO2), pressurized liquid (PLE) and enzyme assisted (EAE) extractions. SFE-CO2 at optimized parameters yielded 11.8 g/100 g of lipophilic fraction, containing 43.3 and 37.4% of α-linolenic and linoleic fatty acids, respectively. The combined PLE with ethanol and water additionally recovered 61.8 g/100 g of polar constituents and reduced the antioxidant capacity of starting material by up to 94%. The major portion of the antioxidants (89-94% in different assays), anthocyanins (231 mg/100 g pomace) and proanthocyanidins (15.9 g/100 g pomace) was present in PLE-EtOH extract. Cyanidin-3-galactoside was the major anthocyanin (146.9 mg/100 g). High-pressure fractionation was more efficient for obtaining bioactive pomace constituents as compared with conventional and enzyme-assisted extractions.


Asunto(s)
Fraccionamiento Químico/métodos , Solventes/química , Vaccinium vitis-Idaea , Administración de Residuos/métodos , Antocianinas/análisis , Antocianinas/química , Antioxidantes/análisis , Antioxidantes/química , Dióxido de Carbono/química , Etanol/química , Frutas/química , Galactósidos/análisis , Galactósidos/química , Tecnología Química Verde , Residuos Industriales , Complejos Multienzimáticos/química , Complejos Multienzimáticos/metabolismo , Presión , Proantocianidinas/análisis , Proantocianidinas/química , Agua
9.
Food Chem ; 318: 126549, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32151920

RESUMEN

Cornelian cherry (CC) fruits a source of bioactive compounds that are still being underutilized. In this study, a comprehensive characterization of 11 Montenegrin CC local or introduced genotypes and cultivars collected in the wild or from organic orchards is provided. Their potential utilizations as natural antioxidants, colorants and organic food ingredients were exploited. CC fruits had high level of vitamin C (48-108 mg/100 g), malic acid (104-375 mg/100 g), and total polyphenols (158-591mgGAE/100 g). They also displayed high antioxidant activity based on DPPH (623-1903µmolTE/100 g), ABTS (441-1475µmolTE/100 g), and FRAP (1509-5954µmolFe2+/100 g) assays. UHPLC-PDA-HESI-MS/MS analyses were used to quantify the concentration of phenolic acids (7.69-19.87 mg/100 g), flavonoids (10.87-44.34 mg/100 g), anthocyanins (11.85-195.43 mg/100 g) and iridoids (129.07-341.20 mg/100 g). For each of this groups, the most abundant were caftaric acid (12.24 mg/100 g), quercetin 3-glucuronide (29.66 mg/100 g), cyanidin 3-O-galactoside (130.93 mg/100 g) and loganic acid (303.3 mg/100 g), respectively. PCA and cluster heatmap analysis highlighted potentials for further exploitation of local genotypes and cultivars through organic food processing and breeding program.


Asunto(s)
Cornus/química , Cornus/genética , Antocianinas/análisis , Antioxidantes/análisis , Ácido Ascórbico/análisis , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , Análisis de los Alimentos/métodos , Frutas/química , Galactósidos/análisis , Iridoides/análisis , Montenegro , Fenoles/análisis , Polifenoles/análisis , Espectrometría de Masas en Tándem
10.
Food Chem ; 315: 126175, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-31991254

RESUMEN

The food industry is increasingly innovating and applying new processing technologies and ingredients to develop novel food products that meet the consumers' demand. In this study, the effect of extrusion (at 140 °C and 160 °C) was evaluated in different lentil flours formulations enriched with nutritional yeast, in terms of α-galactosides (raffinose, stachyose, verbascose), inositol phosphates (IPs), trypsin inhibitors and lectins content. The content of α-galactosides and IPs was determined by high performance liquid chromatography. Trypsin inhibitor activity (TIA) was evaluated using a small-scale quantitative assay. The lectin content was analyzed using a haemagglutination assay and a Competitive Indirect Enzyme-linked immunosorbent assay. Extrusion promoted a significant increase, up to 85% in total α-galactosides content. After extrusion, IPs content was significantly decreased and TIA as well as lectins content had a reduction higher than 90%. Extrusion demonstrated to have a beneficial effect by increasing desirable prebiotic compounds and decreasing non-nutritional factors.


Asunto(s)
Harina/análisis , Alimentos Formulados/análisis , Lens (Planta)/química , Fitoquímicos/química , Levadura Seca/química , Animales , Cromatografía Líquida de Alta Presión , Dieta Sin Gluten , Análisis de los Alimentos/métodos , Industria de Procesamiento de Alimentos/métodos , Galactósidos/análisis , Pruebas de Hemaglutinación , Fosfatos de Inositol/análisis , Oligosacáridos/análisis , Fitoquímicos/análisis , Ratas , Inhibidores de Tripsina/análisis
11.
J Chromatogr A ; 1532: 191-197, 2018 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-29208309

RESUMEN

Hops used in the brewing process of beer for flavoring are known to contain estrogen active compounds (EAC) and to be the source of EAC in beer. The recently developed planar yeast estrogen screen (pYES) with the substrate resorufin-ß-d-galactopyranoside (RGP) successfully was applied for the detection of EAC in ethanolic extracts of hops pellet samples. The only pYES positive compound was identified as the hop flavanone prenylnaringenin (PN) by thin-layer chromatography-mass spectrometry. The heat-induced formation of estrogen active PN from the inactive hop flavonoid desmethylxanthohumol was confirmed by simulation of wort boiling, extraction of both the hops' remainder and the supernatant water, and subsequent investigation of the extracts by pYES. By means of the dose-response curve of PN of a hops' remainder extract, the estradiol equivalent concentration (EEQ) and thus the estradiol equivalent amount (EEA) of PN in the hops' remainder after simulation of the wort boiling was determined to 39 µg/L and 52 µg/kg, respectively.


Asunto(s)
Estrógenos/análisis , Humulus/química , Saccharomyces cerevisiae/metabolismo , Cerveza/análisis , Cromatografía en Capa Delgada , Simulación por Computador , Estradiol/análisis , Galactósidos/análisis , Imagenología Tridimensional , Isomerismo , Espectrometría de Masas , Oxazinas/análisis , Agua/química
12.
Plant Sci ; 262: 91-102, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28716425

RESUMEN

Cranberry flavonoids, including anthocyanins, flavonol glycosides and proanthocyanidins, and organic acids were characterized and quantified by HPLC and LC-MS/MS during fruit development and ripening in eight cranberry cultivars. Anthocyanin biosynthesis initiated at early fruit development and reached highest level in mature fruit, with significant differences between cultivars. Major flavonol glycosides, including the most abundant quercetin-3-galactoside and myricetin-3-galactoside, showed consistent concentrations during the season with moderate fluctuation, and were at similar levels in mature fruits of the eight cultivars. Proanthocyanidins declined during fruit development and then increased slightly in later maturation stages. Levels of various proanthocyanidin oligomers/polymers with different degree-of-polymerization were highly correlated within a cultivar during fruit development. Cultivars with coancestry exhibited similar levels (high/low) of anthocyanins or proanthocyanidins, indicating genetic effects on biosynthesis of such flavonoids. All cultivars showed similar levels of malic and citric acids, and declining levels of quinic acid during fruit development. Benzoic acid was extremely low early in the season and increased sharply during fruit ripening. Levels of quinic and citric acids were significantly different among cultivars in the mature fruit. Concentrations of proanthocyanidins, anthocyanins, quinic acid and benzoic acid have a strong developmental association in developing ovaries.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Flavonoides/análisis , Frutas/química , Espectrometría de Masas en Tándem/métodos , Vaccinium macrocarpon/química , Ácido Benzoico/análisis , Ácido Benzoico/metabolismo , Ácido Cítrico/análisis , Ácido Cítrico/metabolismo , Flavonoides/metabolismo , Galactósidos/análisis , Galactósidos/metabolismo , Malatos/análisis , Malatos/metabolismo , Proantocianidinas/análisis , Proantocianidinas/metabolismo , Quercetina/análogos & derivados , Quercetina/análisis , Quercetina/metabolismo , Ácido Quínico/análisis , Ácido Quínico/metabolismo
13.
Plant Foods Hum Nutr ; 72(2): 205-210, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28447255

RESUMEN

The aim of this research was to evaluate the antioxidant capacity and physical-chemical characteristics of commercial white myrtle berry (Myrtus communis L. var. leucocarpa DC) liqueur (WMBL). The total phenolic (TP) content was measured spectrophotometrically, applying a modified Folin-Ciocalteu's method, and phenolic compounds were identified by high-performance liquid chromatography (HPLC) coupled with electrospray mass spectrometry, and quantified by HPLC coupled with ultraviolet/visible detection. The antioxidant capacities were evaluated by FRAP, CUPRAC, DPPH•, and ABTS•+ assays. The volatiles were assessed by gas chromatography and mass spectrometry (GC-MS/FID) after headspace solid-phase microextraction (HS-SPME) and liquid-liquid extraction (LLE). WMBL showed lower TP levels (636.3 ± 39.2 mg GAE/L) than in purple myrtle berry liqueur (PMBL). Nevertheless, WMBL exhibited better antioxidant capacities, potentially due to high concentrations of gallic acid (294.2 ± 14.2 mg/L) and its derivatives (58.3 ± 2.1 mg/L). Other phenolic compounds detected by HPLC-DAD and LC-MS/MS were flavonols like myricetin and its derivatives (myricetin-3-O-galactoside and myricetin-3-O-rhamnoside) with concentrations similar to those found in PMBL. GC-MS/FID analysis revealed 44 compounds (terpenes, higher aliphatic compounds and shikimic acid pathway derivatives). 1,8-Cineole was the most abundant terpene in the liqueur (26.5% (HS-SPME) and 9.6% (LLE)).


Asunto(s)
Antioxidantes/análisis , Myrtus/química , Fenoles/análisis , Compuestos Orgánicos Volátiles/análisis , Antioxidantes/metabolismo , Ciclohexanoles/análisis , Ciclohexanoles/metabolismo , Eucaliptol , Flavonoides/análisis , Flavonoides/metabolismo , Frutas/química , Galactósidos/análisis , Galactósidos/metabolismo , Ácido Gálico/análisis , Ácido Gálico/metabolismo , Manósidos/análisis , Manósidos/metabolismo , Monoterpenos/análisis , Monoterpenos/metabolismo , Fenoles/metabolismo , Terpenos/análisis , Terpenos/metabolismo , Compuestos Orgánicos Volátiles/metabolismo
14.
J Agric Food Chem ; 65(8): 1684-1696, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28191939

RESUMEN

This study is an exhaustive chemical characterization of the phenolic compounds, triterpenes, and organic and ascorbic acids in red-fleshed apple varieties obtained by different breeding programs and using five traditional and new white-fleshed apple cultivars as reference. To carry out these analyses, solid-liquid extraction (SLE) and ultraperformance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) were used. The results showed that the red-fleshed apples contained, in either the flesh or peel, higher amounts of phenolic acids (chlorogenic acid), anthocyanins (cyanidin-3-O-galactoside), dihydrochalcones (phloretin xylosyl glucoside), and organic acids (malic acid) but a lower amount of flavan-3-ols than the white-fleshed apples. These quantitative differences could be related to an up-regulation of anthocyanins, dihydrochalcones, and malic acid and a down-regulation of flavan-3-ols (anthocyanin precursors) in both the flesh and peel of the red-fleshed apple varieties. The reported results should be considered preliminary because the complete phytochemical characterization of the red-fleshed apple cultivars will be extended to consecutive harvest seasons.


Asunto(s)
Malus/química , Fitoquímicos/análisis , Extractos Vegetales/análisis , Antocianinas/análisis , Frutas/química , Frutas/clasificación , Galactósidos/análisis , Malus/clasificación , Polifenoles/análisis , Espectrometría de Masas en Tándem
15.
Cold Spring Harb Protoc ; 2016(12)2016 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-27934685

RESUMEN

In this protocol, we present a qualitative assay for monitoring the level of expression of ß-galactosidase, an enzyme encoded by the LacZ gene, in yeast. This is useful both for determining autoactivity of LacZ expression in yeast DNA "bait" strains and for assessing LacZ reporter gene activation mediated by a transcription factor "prey" interaction with a DNA bait of interest in yeast one-hybrid (Y1H) assays. In this colorimetric assay, yeast are lysed in liquid nitrogen and then assayed for ß-galactosidase expression using the colorless compound X-gal, which turns blue in the presence of this enzyme.


Asunto(s)
Colorimetría/métodos , beta-Galactosidasa/análisis , Galactósidos/análisis , Indoles/análisis , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genética , Coloración y Etiquetado , Técnicas del Sistema de Dos Híbridos
16.
Food Chem ; 212: 87-95, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27374510

RESUMEN

The effect of microwave and heat pretreatment on the content and composition of anthocyanins, phenolics, and the antioxidant capacity of hawthorn drink were studied. Nine anthocyanins were isolated by chromatographic separation from the Zirou hawthorn source and their structure identified using HPLC-DAD-ESI/MS analysis. Heat and microwave pretreatments had a significant impact on the relative contents of hawthorn anthocyanins, such as cyanidin-3-galactoside (82.9% and 76.9%, respectively) and cyanidin-3-glucoside (9.2% and 11.5%, respectively). Pretreatment had no significant effect on pH, total soluble solid or total acid. More anthocyanins remained after heat treatment than after microwaving (0.745mg/100mL), and were 52.4% higher than the control group after storage for 7days. The colour density of the heat treated group was higher than the control group (24.5%) after 12days of fermentation. The main antioxidant capacities of the hawthorn drinks came from total polyphenolics rather than total anthocyanins or total flavonoids.


Asunto(s)
Antocianinas/análisis , Antioxidantes/análisis , Crataegus/química , Fermentación , Fenoles/análisis , Extractos Vegetales/química , Galactósidos/análisis , Glucósidos/análisis , Espectrometría de Masas
17.
J Sci Food Agric ; 96(15): 4951-4961, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27407065

RESUMEN

BACKGROUND: The tea plant, Camellia sinensis (L.) O. Kuntz, is a perennial woody plant widely cultivated for the production of a popular non-alcoholic beverage. To rapidly identify and evaluate two different color tea varieties (yellowish and purplish), the main phenotypic traits and quality components were tested in the present study. The metabolic profiles of tea shoots and leaves were also analyzed using liquid chromatography-tandem mass spectrometry. RESULTS: The yellowish variation had a higher active level with respect to metabolism of catechins, and the contents of luteolin and kaempferol 3-α-d-glucoside were much higher compared to in the other variations. However, the purplish variation had a low content of theanine and a high content of caffeine. The contents of quercetin and kaempferol 3-α-d-galactoside were highest in purplish leaves. Moreover, the yellowish variation had the highest total quality scores for green teas and black teas, whereas the purplish variation had the highest scores for oolong teas. CONCLUSION: Both the yellowish variation and the purplish variation represent excellent breeding materials and are worthy of breeding as new tea cultivars. The yellowish variation is more suitable for making high-grade green teas or black teas, whereas the purplish variation is suitable for producing fine quality oolong teas. © 2016 Society of Chemical Industry.


Asunto(s)
Camellia sinensis/química , Color , Flavonoides/análisis , Té/química , Cruzamiento , Catequina/metabolismo , Cromatografía Liquida , Galactósidos/análisis , Glucósidos/análisis , Quempferoles/análisis , Luteolina/análisis , Fenotipo , Extractos Vegetales/química , Hojas de la Planta/química , Brotes de la Planta/química , Especificidad de la Especie , Espectrometría de Masas en Tándem
18.
J Chromatogr A ; 1447: 64-71, 2016 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-27109198

RESUMEN

Flavonol glycosides are important components of leaves from vascular plants. A lot of isomers of these compounds are produced by plants, making their analysis very difficult and causing many structural misinterpretations. Galactosides and glucosides as mono- or oligosaccharides yield many diastereoisomers, hindering the analysis by mass spectrometry. In order to enable the mass spectrometric distinctions of these isomers, in this work we combine an isopropylidene based chemical derivatization with liquid chromatography with multiple-stage mass spectrometry (LC-MS(n)) analysis. The isomers of flavonol triglycosides, after the reaction, yielded products with different molecular weight, therefore, they were no longer isomers, allowing their identification by MS(1) analysis. However, to the 4 isomers of flavonol diglycosides, only one yielded, after isopropylidenation, a product with different molecular weight. To the other 3 species, the incorporation of 2 isopropylidene groups retained them in the isomeric form. For such species, chromatographic separation and MS(n) detection targeting the lithium adducts of 3,4-O-isopropylidene-galactosyl or 4,6-O-isopropylidene-glucosyl residues (m/z 209.099) provided specific MS profile.


Asunto(s)
Flavonoles/análisis , Glicósidos/análisis , Maytenus/química , Cromatografía Liquida , Galactósidos/análisis , Glucósidos/análisis , Hojas de la Planta/química , Estereoisomerismo , Espectrometría de Masas en Tándem/métodos
19.
Phytochem Anal ; 27(1): 64-72, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26464348

RESUMEN

INTRODUCTION: Powder-like extract of Ricinus communis seeds contain a toxic protein, ricin, which has a history of military, criminal and terroristic use. As the detection of ricin in this "terrorist powder" is difficult and time-consuming, related low mass metabolites have been suggested to be useful for screening as biomarkers of ricin. OBJECTIVE: To apply a comprehensive NMR-based analysis strategy for annotation, isolation and structure elucidation of low molecular weight plant metabolites of Ricinus communis seeds. METHODOLOGY: The seed extract was prepared with a well-known acetone extraction approach. The common metabolites were annotated from seed extract dissolved in acidic solution using (1)H NMR spectroscopy with spectrum library comparison and standard addition, whereas unconfirmed metabolites were identified using multi-step off-line HPLC-DAD-NMR approach. RESULTS: In addition to the common plant metabolites, two previously unreported compounds, 1,3-digalactoinositol and ricinyl-alanine, were identified with support of MS analyses. CONCLUSION: The applied comprehensive NMR-based analysis strategy provided identification of the prominent low molecular weight metabolites with high confidence.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Ricinus/química , Ricinus/metabolismo , Semillas/química , Alanina/análogos & derivados , Alanina/análisis , Alanina/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Galactósidos/análisis , Galactósidos/química , Inositol/análogos & derivados , Inositol/análisis , Inositol/química , Estructura Molecular , Peso Molecular , Piridonas/análisis , Piridonas/metabolismo , Ricina/metabolismo , Semillas/metabolismo
20.
J Agric Food Chem ; 63(6): 1698-710, 2015 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-25619228

RESUMEN

The water status of Medicago truncatula Gaertn. seed was followed by low-field NMR relaxometry during germination with and without oryzalin or fusicoccin used as growth modulators. T1 and T2 relaxation times and proportions P1 and P2 were determined on fresh, frozen, and freeze-thawed samples to characterize changes in water dynamics and compartmentation and in the nonfreezing water fraction. The results demonstrate that low-field NMR relaxometry allowed differentiating germination phases and events occurring during them as well as perturbations related to the presence of growth modulators. The results provide clear evidence that the classical multicomponent relaxation interpretation cannot directly relate T2 components and morphological compartments in biological tissue.


Asunto(s)
Germinación/fisiología , Espectroscopía de Resonancia Magnética/métodos , Medicago truncatula , Semillas/metabolismo , Semillas/ultraestructura , Agua/metabolismo , Carbohidratos/análisis , Dinitrobencenos/farmacología , Congelación , Galactósidos/análisis , Glicósidos/farmacología , Calor , Medicago truncatula/efectos de los fármacos , Reguladores del Crecimiento de las Plantas/farmacología , Semillas/efectos de los fármacos , Sulfanilamidas/farmacología
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