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1.
Nutrients ; 15(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37242278

RESUMO

Effects of two foods with bioactive constituents (black tea brew, BTB and grape seed powder, GSP) on lipid digestibility was studied. Lipolysis inhibitory effect of these foods was examined using two test foods (cream and baked beef) with highly different fatty acid (FA) composition. Digestion simulations were performed either using both gastric and pancreatic lipase, or only with pancreatic lipase according to the Infogest protocol. Lipid digestibility was assessed based on the bioaccessible FAs. Results showed the triacylglycerols containing short- and medium-chain FAs (SCFA and MCFA) are non-preferred substrates for pancreatic lipase; however, this is not characteristic for GL. Our findings suggest that both GSP and BTB primarily affect the lipolysis of SCFAs and MCFAs, because the dispreference of pancreatic lipase towards these substrates was further enhanced as a result of co-digestion. Interestingly, GSP and BTB similarly resulted in significant decrease in lipolysis for cream (containing milk fat having a diverse FA profile), whereas they were ineffective in influencing the digestion of beef fat, having simpler FA profile. It highlights that the characteristics of the dietary fat source of a meal can be a key determinant on the observed extent of lipolysis when co-digested with foods with bioactive constituents.


Assuntos
Vitis , Animais , Bovinos , Pós , Chá , Modelos Biológicos , Lipólise , Lipase/metabolismo , Triglicerídeos/química , Ácidos Graxos , Digestão
3.
Bioengineering (Basel) ; 9(9)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36134964

RESUMO

The objective of the investigation was to understand the biochemical activities of hydrolysate of soybean milk protein (SMP). Hydrolysis was carried out by different concentrations of papain (0.008 g·L-1, 0.016 g·L-1, 0.032 g·L-1 and 0.064 g·L-1). The antioxidant capacity was measured by the ferric-reducing ability of plasma (FRAP) and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assays. The anti-angiotensin activity of hydrolysate was measured by the recombinant angiotensin converting enzyme and substrate Abz-FRK(Dnp)-P. The contributions of the Kunitz trypsin inhibitor (KTI) and Bowman-Birk inhibitor (BBI) on antigenicity, and the in vitro digestion of papain-hydrolyzed SMP were studied. Rabbit polyclonal anti-KTI and anti-BBI antibodies together with peroxidase-labelled goat anti-Rb IgG secondary antibody were used to identify the antigenicity of KTI and BBI in unhydrolyzed and papain-hydrolyzed SMP. The antioxidant capacity and anti-angiotensin activity of SMP were increased after the papain hydrolysis of SMP. The KTI- and BBI-specific antigenicity were reduced in SMP by increasing the concentration of papain. However, there was interaction between papain-hydrolyzed SMP and trypsin in native gel, while interaction with chymotrypsin was absent. The interaction between trypsin and SMP was reduced due to the hydrolysis of papain in a concentration-dependent manner. According to the in vitro gastrointestinal digestion simulation protocol (Infogest), the digestibility of SMP was not statistically increased.

4.
Nutrients ; 13(11)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34836142

RESUMO

The nutritional relevance of food compositional data could be improved by taking the bioaccessibility of these constituents into account. A lack of routine methods to assess the bioaccessibility of fatty acids (FAs) in food is one of the limiting factors of doing so. An analytical protocol is proposed for routine assessment of the extent of lipolysis via in vitro digestion simulation methods in food products. The established method provides specific information on each FA individually. Steps of the protocol including the Bligh and Dyer chloroform/methanol/water extraction of esterified and free FAs from in vitro digesta, methyl ester derivatization, and GC-FID analysis were specifically tailored to help routine work and were harmonized with the Infogest in vitro digestion simulation protocol (both v1.0 and v2.0). The method was applied to assess the degree of FA-specific lipolysis in a baked fish (carp) meal and the results showed that the FA composition of the original food significantly differed from that of the distribution of FFAs in the digesta. The use of gastric lipase (in Infogest v2.0 protocol) increased total FA release by 9.5% and its specific impact on palmitic acid was the most prominent.


Assuntos
Cromatografia Gasosa/métodos , Digestão , Ácidos Graxos/análise , Técnicas In Vitro/métodos , Lipólise/efeitos dos fármacos , Ácidos Graxos não Esterificados/análise , Humanos , Modelos Biológicos , Valor Nutritivo , Alimentos Marinhos/análise
5.
Food Chem ; 357: 129757, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33872868

RESUMO

Prediction of retention times (RTs) is increasingly considered in untargeted metabolomics to complement MS/MS matching for annotation of unidentified peaks. We tested the performance of PredRet (http://predret.org/) to predict RTs for plant food bioactive metabolites in a data sharing initiative containing entry sets of 29-103 compounds (totalling 467 compounds, >30 families) across 24 chromatographic systems (CSs). Between 27 and 667 predictions were obtained with a median prediction error of 0.03-0.76 min and interval width of 0.33-8.78 min. An external validation test of eight CSs showed high prediction accuracy. RT prediction was dependent on shape and type of LC gradient, and number of commonly measured compounds. Our study highlights PredRet's accuracy and ability to transpose RT data acquired from one CS to another CS. We recommend extensive RT data sharing in PredRet by the community interested in plant food bioactive metabolites to achieve a powerful community-driven open-access tool for metabolomics annotation.

6.
Front Microbiol ; 11: 585428, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33408702

RESUMO

The gut microbiota plays a pivotal role in the conversion of dietary flavonoids, which can affect their bioavailability and bioactivity and thereby their health-promoting properties. The ability of flavonoids to metabolically-activate the microbiota has, however, not been systematically evaluated. In the present study, we used a fluorescence-based single-cell activity measure [biorthogonal non-canonical ammino acid-tagging (BONCAT)] combined with fluorescence activated cell sorting (FACS) to determine which microorganisms are metabolically-active after amendment of the flavonoid rutin. We performed anaerobic incubations of human fecal microbiota amended with rutin and in the presence of the cellular activity marker L-azidohomoalanine (AHA) to detect metabolically-active cells. We found that 7.3% of cells in the gut microbiota were active after a 6 h incubation and 26.9% after 24 h. We then sorted BONCAT-positive cells and observed an enrichment of Lachnospiraceae (Lachnoclostridium and Eisenbergiella), Enterobacteriaceae, Tannerellaceae, and Erysipelotrichaceae species in the rutin-responsive fraction of the microbiota. There was marked inter-individual variability in the appearance of rutin conversion products after incubation with rutin. Consistent with this, there was substantial variability in the abundance of rutin-responsive microbiota among different individuals. Specifically, we observed that Enterobacteriaceae were associated with conversion of rutin into quercetin-3-glucoside (Q-glc) and Lachnospiraceae were associated with quercetin (Q) production. This suggests that individual microbiotas differ in their ability to metabolize rutin and utilize different conversion pathways.

7.
Metabolites ; 8(3)2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30149593

RESUMO

Bioactive compounds present in plant-based foods, and their metabolites derived from gut microbiota and endogenous metabolism, represent thousands of chemical structures of potential interest for human nutrition and health. State-of-the-art analytical methodologies, including untargeted metabolomics based on high-resolution mass spectrometry, are required for the profiling of these compounds in complex matrices, including plant food materials and biofluids. The aim of this project was to compare the analytical coverage of untargeted metabolomics methods independently developed and employed in various European platforms. In total, 56 chemical standards representing the most common classes of bioactive compounds spread over a wide chemical space were selected and analyzed by the participating platforms (n = 13) using their preferred untargeted method. The results were used to define analytical criteria for a successful analysis of plant food bioactives. Furthermore, they will serve as a basis for an optimized consensus method.

8.
J Nutr Biochem ; 59: 160-172, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30055451

RESUMO

Tart cherries have been reported to exert potential health benefits attributed to their specific and abundant polyphenol content. However, there is a need to study the impact and fate of tart cherries polyphenols in the gut microbiota. Here, tart cherries, pure polyphenols (and apricots) were submitted to in vitro bacterial fermentation assays and assessed through 16S rRNA gene sequence sequencing and metabolomics. A short-term (5 days, 8 oz. daily) human dietary intervention study was also conducted for microbiota analyses. Tart cherry concentrate juices were found to contain expected abundances of anthocyanins (cyanidin-glycosylrutinoside) and flavonoids (quercetin-rutinoside) and high amounts of chlorogenic and neochlorogenic acids. Targeted metabolomics confirmed that gut microbes were able to degrade those polyphenols mainly to 4-hydroxyphenylpropionic acids and to lower amounts of epicatechin and 4-hydroxybenzoic acids. Tart cherries were found to induce a large increase of Bacteroides in vitro, likely due to the input of polysaccharides, but prebiotic effect was also suggested by Bifidobacterium increase from chlorogenic acid. In the human study, two distinct and inverse responses to tart cherry consumption were associated with initial levels of Bacteroides. High-Bacteroides individuals responded with a decrease in Bacteroides and Bifidobacterium, and an increase of Lachnospiraceae, Ruminococcus and Collinsella. Low-Bacteroides individuals responded with an increase in Bacteroides or Prevotella and Bifidobacterium, and a decrease of Lachnospiraceae, Ruminococcus and Collinsella. These data confirm that gut microbiota metabolism, in particular the potential existence of different metabotypes, needs to be considered in studies attempting to link tart cherries consumption and health.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/fisiologia , Polifenóis/farmacologia , Prunus avium/química , Adulto , Bifidobacterium/efeitos dos fármacos , Bifidobacterium/genética , Feminino , Fermentação , Sucos de Frutas e Vegetais , Microbioma Gastrointestinal/genética , Humanos , Masculino , Fenóis/metabolismo , Polifenóis/análise , Polifenóis/farmacocinética
9.
Food Chem ; 267: 263-270, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29934166

RESUMO

The effect of temperature (6, 15 and 30°C) during ageing on the colour, phytochemical composition and bioactivity of roselle wine was investigated over 12months. At the end of ageing, wines stored at 6°C had the highest colour density and lowest polymeric anthocyanins. The initial concentration of most of the individual phenolic compounds decreased during ageing, with reduction of monomeric anthocyanins contributing to the formation of anthocyanin-derivatives (pyranoanthocyanins), eight of which were identified tentatively and reported here for the first time in roselle wine. The decrease in individual phenolic compounds did not affect inhibition of α-glucosidase (maltase) activity, which remained relatively low but stable throughout ageing. Diethyl succinate was the only volatile clearly influenced by ageing temperature, with the most pronounced effect at 30°C (∼256 fold increase). In summary, the final concentrations of anthocyanins and diethyl succinate were the major compounds influenced by ageing temperature.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Hibiscus/química , Compostos Fitoquímicos/química , Vinho/análise , alfa-Glucosidases/metabolismo , Antocianinas/análise , Cromatografia Líquida de Alta Pressão , Cor , Hibiscus/metabolismo , Fenóis/análise , Compostos Fitoquímicos/análise , Temperatura , Fatores de Tempo , Compostos Orgânicos Voláteis/análise , alfa-Glucosidases/química
10.
Sci Rep ; 8(1): 5471, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29615674

RESUMO

Transient hyperglycaemia is a risk factor for type 2 diabetes and endothelial dysfunction, especially in subjects with impaired glucose tolerance. Nutritional interventions and strategies for controlling postprandial overshoot of blood sugars are considered key in preventing progress to the disease state. We have identified apigenin-7-O-glucoside, apigenin, and (Z) and (E)-2-hydroxy-4-methoxycinnamic acid glucosides as the active (poly)phenols in Chamomile (Matricaria recutita) able to modulate carbohydrate digestion and absorption in vitro as assessed by inhibition of α-amylase and maltase activities. The latter two compounds previously mistakenly identified as ferulic acid hexosides were purified and characterised and studied for their contribution to the overall bioactivity of chamomile. Molecular docking studies revealed that apigenin and cinnamic acids present totally different poses in the active site of human α-amylase. In differentiated Caco-2/TC7 cell monolayers, apigenin-7-O-glucoside and apigenin strongly inhibited D-[U-14C]-glucose and D-[U-14C]-sucrose transport, and less effectively D-[U-14C]-fructose transport. Inhibition of D-[U-14C]-glucose transport by apigenin was stronger under Na+-depleted conditions, suggesting interaction with the GLUT2 transporter. Competitive binding studies with molecular probes indicate apigenin interacts primarily at the exofacial-binding site of GLUT2. Taken together, the individual components of Chamomile are promising agents for regulating carbohydrate digestion and sugar absorption at the site of the gastrointestinal tract.


Assuntos
Camomila/metabolismo , Hiperglicemia/metabolismo , Polifenóis/metabolismo , Animais , Ácidos Cumáricos/metabolismo , Glicosilação , Ratos , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
11.
J Chromatogr A ; 1534: 111-122, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29290399

RESUMO

Fatty acyl-Coenzyme A species (acyl-CoAs) are key biomarkers in studies focusing on cellular energy metabolism. Existing analytical approaches are unable to simultaneously detect the full range of short-, medium-, and long-chain acyl-CoAs, while chromatographic limitations encountered in the analysis of limited amounts of biological samples are an often overlooked problem. We report the systematic development of a UHPLC-ESI-MS/MS method which incorporates reversed phase (RP) and hydrophilic interaction liquid chromatography (HILIC) separations in series, in an automated mode. The protocol outlined encompasses quantification of acyl-CoAs of varying hydrophobicity from C2 to C20 with recoveries in the range of 90-111 % and limit of detection (LOD) 1-5 fmol, which is substantially lower than previously published methods. We demonstrate that the poor chromatographic performance and signal losses in MS detection, typically observed for phosphorylated organic molecules, can be avoided by the incorporation of a 0.1% phosphoric acid wash step between injections. The methodological approach presented here permits a highly reliable, sensitive and precise analysis of small amounts of tissues and cell samples as demonstrated in mouse liver, human hepatic (HepG2) and skeletal muscle (LHCNM2) cells. The considerable improvements discussed pave the way for acyl-CoAs to be incorporated in routine targeted lipid biomarker profile studies.


Assuntos
Acil Coenzima A/análise , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Espectrometria de Massas em Tandem , Acil Coenzima A/química , Animais , Linhagem Celular , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Fígado/química , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/química , Músculo Esquelético/metabolismo
12.
J Agric Food Chem ; 65(18): 3602-3608, 2017 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28420230

RESUMO

The history of the acyl-quinic acids is briefly reviewed, the merits and limitations of the various nomenclature systems applicable are critically compared, and their limitations are highlighted, in particular their inability to provide an unambiguous description of all quinic acid enantiomers and diastereoisomers and associated acyl-quinic acids. Recommendations are made for a nomenclature system that in combination with IUPAC numbering achieves this objective. A comprehensive set of structures for the quinic acid enantiomers and diastereoisomers is presented. The Supporting Information provides an explanation of trivial names and a decision tree to determine which quinic acid isomer a structure represents.


Assuntos
Ácido Clorogênico/química , Ácido Quínico/química , Isomerismo , Estrutura Molecular , Terminologia como Assunto
13.
J Nutr Biochem ; 39: 156-168, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27840292

RESUMO

Dietary fiber-derived short-chain fatty acids (SCFA) and phenolics produced by the gut microbiome have multiple effects on health. We have tested the hypothesis that long-term exposure to physiological concentrations of SCFA can affect the transport and metabolism of (poly)phenols by the intestinal epithelium using the Caco-2 cell model. Metabolites and conjugates of hesperetin (HT) and ferulic acid (FA), gut-derived from dietary hesperidin and chlorogenic acid, respectively, were quantified by LC-MS with authentic standards following transport across differentiated cell monolayers. Changes in metabolite levels were correlated with effects on mRNA and protein expression of key enzymes and transporters. Propionate and butyrate increased both FA transport and rate of appearance of FA glucuronide apically and basolaterally, linked to an induction of MCT1. Propionate was the only SCFA that augmented the rate of formation of basolateral FA sulfate conjugates, possibly via basolateral transporter up-regulation. In addition, propionate enhanced the formation of HT glucuronide conjugates and increased HT sulfate efflux toward the basolateral compartment. Acetate treatment amplified transepithelial transport of FA in the apical to basolateral direction, associated with lower levels of MCT1 protein expression. Metabolism and transport of both HT and FA were curtailed by the organic acid lactate owing to a reduction of UGT1A1 protein levels. Our data indicate a direct interaction between microbiota-derived metabolites of (poly)phenols and SCFA through modulation of transporters and conjugating enzymes and increase our understanding of how dietary fiber, via the microbiome, may affect and enhance uptake of bioactive molecules.


Assuntos
Ácidos Graxos Voláteis/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Polifenóis/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Acetatos/farmacologia , Transporte Biológico , Butiratos/farmacologia , Células CACO-2 , Ácidos Cumáricos/metabolismo , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Hesperidina/metabolismo , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/microbiologia , Lactatos/farmacologia , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Propionatos/farmacologia , Simportadores/genética , Simportadores/metabolismo
14.
J Mass Spectrom ; 51(12): 1130-1145, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27591562

RESUMO

Hydroxycinnamoylquinic acids (HCQAs) are a major class of phenolic plant secondary metabolites, belonging to the chlorogenic acid family. Various health-beneficial properties of HCQAs have been shown, which has drawn interest for HCQA profiling in plants of human consumption. However, this task remains challenging, because several isomeric HCQAs can be present in the sample with identical molecular formulae and the limited availability of reference standards poses additional challenges to their identification. In the present work, a high performance liquid chromatography-electrospray ionization-quadrupole time-of-flight-mass spectrometry (HPLC-ESI-Q/TOF-MS) method accompanied with an effective data filtering protocol is presented, which is shown to be suitable for the identification of HCQAs in plant materials in a non-targeted manner. Both collision-induced dissociation (CID) fragmentation performed in a collision cell and in-source (CID) fragmentation were used to produce accurate mass fragments. It was shown that fragmentation characteristics required for identification of regio-isomers of HCQAs can be achieved with in-source CID fragmentation, enabling the use of a single-stage MS system with in-source fragmentation for convincing identification of HCQAs. Based on a thorough validation of identified HCQA compounds using coffee bean extracts as reference samples, comprehensive profiling of HCQAs in two apricot (Prunus armeniaca L.) genotypes ('Preventa' and 'Gönci magyarkajszi') was carried out for the first time and the following 10 HCQAs were shown to be present in apricot fruit: 3-caffeoylquinic acid (CQA), cis-3-CQA, 4-CQA, 5-CQA, cis-5-CQA, 3,5-diCQA, 3-p-coumaroylquinic acid (pCoQA), 4-pCoQA, 3-feruloylquinic acid (FQA) and cis-3-FQA. Copyright © 2016 John Wiley & Sons, Ltd. HIGHLIGHTS: An HPLC-ESI-Q/TOF-MS method suitable for the identification of hydroxycinnamoyilquinic acids (HCQAs) in plant material in a non-targeted manner was developed. Single-stage, high-resolution MS system with in-source fragmentation was shown to be suitable for convincing identification of HCQAs. Comprehensive profiling of HCQAs in two apricot (Prunus armeniaca L.) genotypes was carried out for the first time. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Ácidos Cumáricos/química , Espectrometria de Massas/métodos , Extratos Vegetais/química , Ácido Quínico/química , Cromatografia Líquida de Alta Pressão , Coffea/química , Frutas/química , Prunus armeniaca/química , Sementes/química
15.
J Agric Food Chem ; 64(19): 3733-42, 2016 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-27096876

RESUMO

The aim of this study is to examine the effect of arbuscular mycorrhizal fungi (AMF) colonization on biomass, polyphenol profile, and content of economically important herbs. A pot experiment was performed with marjoram, lemon balm, and marigold applying a commercially available AMF mixture for inoculation. Major polyphenols were identified using HPLC-UV-ESI-qTOFMS on the basis of their UV-vis and mass spectral characteristics, and selected ones were quantified. We showed that AMF can provide different services for each herb. Marjoram had the highest level of fungal colonization (82 M%) followed by lemon balm (62 M%) and marigold (17 M%). AMF inoculation significantly increased the biomass of marjoram (1.5-fold), the number of marigold flowers (1.2-fold), and the yield of rosmarinic acid and lithospermic acid isomers of marjoram (1.5-fold) and lemon balm (1.2-fold). Therefore, the quantity and quality of plant material could be improved by the application of optimized AMF inoculum.


Assuntos
Calendula/crescimento & desenvolvimento , Melissa/crescimento & desenvolvimento , Micorrizas/fisiologia , Origanum/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta
16.
Plant Foods Hum Nutr ; 70(4): 408-13, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26449220

RESUMO

The aims of the present study were to clarify in vivo effects of three sour cherry cultivars characterized by different polyphenolic composition in hyperlipidemic animals in a short term experiment. The three different sour cherry cultivars were chosen based on their total in vitro antioxidant capacity, total polyphenolic, monomeric anthocyanin and flavonoid content. Male Wistar rats were divided randomly into eight groups: rats kept on normal diet (control) and normal diet supplied with sour cherry powder of one of the three cultivars; others were kept on fat-rich diet and fat-rich diet supplied with sour cherry powder prepared from one of the three cultivars. The treatment lasted 10 days. Lyophilized sour cherry administered in the diet decreased both total cholesterol and LDL cholesterol levels, and increased the HDL cholesterol concentration in sera of hyperlipidemic animals. Significant differences were found in the efficacy of different sour cherry cultivars in case of hyperlipidemia. Sour cherries characterized by higher polyphenol content seem to have a more pronounced effect on serum cholesterol levels. Our results suggest that besides anthocyanins, colourless polyphenols also have lipid lowering effect.


Assuntos
Antioxidantes/uso terapêutico , Frutas/química , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Polifenóis/análise , Prunus avium/química , Animais , Antocianinas/análise , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Dieta , Gorduras na Dieta/administração & dosagem , Flavonoides/análise , Hiperlipidemias/sangue , Masculino , Fitoterapia , Ratos , Ratos Wistar , Especificidade da Espécie
17.
J Mass Spectrom ; 50(1): 71-80, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25601677

RESUMO

In fields such as food and nutrition science or plant physiology, interest in untargeted profiling of flavonoids continues to expand. The group of flavonoids encompasses several thousands of chemically distinguishable compounds, among which are a number of isobaric compounds with the same elemental composition. Thus, the mass spectrometric identification of these compounds is challenging, especially when reference standards are not available to support their identification. Many different types of isomers of flavonoid glycoconjugates are known, i.e. compounds that differ in their glycosylation position, glycan sequence or type of interglycosidic linkage. This work focuses on the mass spectrometric identification of flavonoid glycoconjugate isomers possessing the same glycan mass and differing only in their aglycone core. A non-targeted HPLC-ESI-MS/MS profiling method using a triple quadrupole MS is presented herein, which utilizes in-source fragmentation and a pseudo-MS(3) approach for the selective analysis of flavonoid glycoconjugates with isomeric/isobaric aglycones. A selective MRM-based identification of the in-source formed isobaric aglycone fragments was established. Additionally, utilizing the precursor scanning capability of the employed triple quadrupole instrument, the developed method enabled the determination of the molecular weight of the studied intact flavonoid glycoconjugate. The versatility of the method was proven with various types of flavonoid aglycones, i.e. anthocyanins, flavonols, flavones, flavanones and isoflavones, along with their representative glycoconjugates. The developed method was also successfully applied to a commercially available sour cherry sample, in which 16 different glycoconjugates of pelargonidin, genistein, cyanidin, kaempferol and quercetin could be tentatively identified, including a number of compounds containing isomeric/isobaric aglycones.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Glicoconjugados/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Flavanonas/análise , Flavanonas/química , Flavonoides/química , Flavonóis/análise , Flavonóis/química , Análise de Alimentos/métodos , Glicoconjugados/química , Íons , Isoflavonas/análise , Isoflavonas/química , Isomerismo , Estrutura Molecular , Peso Molecular , Prunus/química , Espectrometria de Massas por Ionização por Electrospray/instrumentação , Espectrometria de Massas em Tandem/instrumentação
18.
Food Chem ; 166: 215-222, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25053048

RESUMO

The isoflavone genistein on the contrary to its well-established health-beneficial effects is not a major component of the Western diet, since soy consumption, considered as the main dietary source of genistein, in these populations is low. Genistein compounds in twelve commercial sour cherry (Prunus cerasus L.) cultivars grown in Hungary were studied. High performance liquid chromatography coupled to electrospray ionisation quadrupole/time-of-flight mass spectrometry (HPLC-ESI-qToF-MS) was used for screening and confirmatory analyses. Genistin and genistein were found in 'Pipacs1', 'Kántorjánosi', 'Debreceni botermo' and 'Éva', which are native cultivars to Hungary. Genistein content of the latter three were in the range of 0.4-0.6, while in 'Pipacs1' in total 4.4 mg genistein compounds were measured expressed as aglycone equivalents per 100g of fresh fruit flesh. These cultivars may play important role as complementary genistein sources in the Western diet. Especially 'Pipacs 1', may be best utilised in functional food products.


Assuntos
Frutas/química , Genisteína/análise , Glicoconjugados/química , Extratos Vegetais/química , Prunus/química
19.
J Chromatogr A ; 1249: 83-91, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-22742894

RESUMO

In recent years, the detection and characterization of relevant pesticide metabolites in food is an important task in order to evaluate their formation, kinetics, stability, and toxicity. In this article, a methodology for the systematic screening of pesticides and their main metabolites in fruit and vegetable samples is described, using LC-HRMS and accurate-mass database search of parent compounds and their diagnostic fragment ions. The approach is based on (i) search for parent pesticide molecules; (ii) search for their metabolites in the positive samples, assuming common fragmentation pathways between the metabolites and parent pesticide molecules; and (iii) search for pesticide conjugates using the data from both parent species and diagnostic fragment ions. An accurate-mass database was constructed consisting of 1396 compounds (850 parent compounds, 447 fragment ions and 99 metabolites). The screening process was performed by the software in an automated fashion. The proposed methodology was evaluated with 29 incurred samples and the output obtained was compared to standard pesticide testing methods (targeted LC-MS/MS). Examples on the application of the proposed approach are shown, including the detection of several pesticide glycosides derivatives, which were found with significantly relevant intensities. Glucose-conjugated forms of parent compounds (e.g., fenhexamid-O-glucoside) and those of metabolites (e.g., despropyl-iprodione-N-glycoside) were detected. Facing the lack of standards for glycosylated pesticides, the study was completed with the synthesis of fenhexamid-O-glucoside for quantification purposes. In some cases the pesticide derivatives were found in a relatively high ratio, drawing the attention to these kinds of metabolites and showing that they should not be neglected in multi-residue methods. The global coverage obtained on the 29 analyzed samples showed the usefulness and benefits of the proposed approach and highlights the practical benefit obtained when the so-called screening methods are used as a complementary tool to standard targeted LC-MS/MS methods.


Assuntos
Cromatografia Líquida/métodos , Análise de Alimentos , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Automação , Estudos Retrospectivos
20.
Anal Bioanal Chem ; 403(4): 995-1006, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22399119

RESUMO

In this work, a systematic comprehensive screening procedure has been proposed for the detection of multiclass flavonoid derivatives by liquid chromatography high-resolution mass spectrometry (LC-HRMS). The procedure is based on the combined use of accurate mass measurements and in-source fragmentation obtained with a liquid chromatography time-of-flight mass spectrometry instrument. The method relies on automated screening of selected diagnostic ions based on an exact mass database. The included diagnostic ions represent theoretical combinations of aglycones and typical glycan part constituents of flavonoid derivatives (i.e., various saccharide units and acyl moieties). The proposed identification protocol is following a systematic evaluation of the obtained positive hits from the diagnostic ions database according to a "bottom-up" approach that is thoroughly discussed. The main benefit of the proposed bottom-up protocol resides in the fact that untargeted flavonoid derivatives can be detected and tentatively identified without the need for any preliminary knowledge on the sought compound. In addition to information on the nature of the (1) aglycone and the (2) glycan part, further indication of (3) sugar unit distribution and information on (4) the type of the glycosidic bonds can also be attained. Selected examples of plant extracts demonstrate the potential of the proposed LC-HRMS approach for the systematic screening of flavonoids. A broad variety of compounds were tentatively identified including both anthocyanins and non-anthocyanin flavonoids having various glycan moieties such as mono-, di-, and triglycosides with varying distributions and linkage types of carbohydrate moieties (O-glycosides, C-glycosides, O,C-glycosides).


Assuntos
Cromatografia Líquida/métodos , Flavonoides/análise , Espectrometria de Massas/métodos , Extratos Vegetais/análise , Plantas/química
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