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Francisco A Tomasbarberan - One of the best experts on this subject based on the ideXlab platform.
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metabolism of Ellagitannins from jabuticaba myrciaria jaboticaba in normoweight overweight and obese brazilians unexpected laxative effects influence urolithins urinary excretion and metabotype distribution
Journal of Functional Foods, 2019Co-Authors: Kim Ohanna Pimenta Inada, Francisco A Tomasbarberan, Daniel Perrone, Mariana MonteiroAbstract:Abstract This is the first study on ellagitannin metabolism in a non-European population, through consumption of jabuticaba, a Brazilian berry. From 35 volunteers (19 normoweight and 16 overweight or obese), 63% reported the occurrence of diarrhea, probably caused by the high amount of Ellagitannins consumed. Urolithin excretion showed high interindividual variability (1.77–522 μmol) and was reduced by diarrhea, but not affected by gender or nutritional status. As reported for Europeans, three urolithin metabotypes (A, B and 0) were observed in Brazilians, with a higher prevalence of metabotype B in overweight and obese individuals (37.5%) than normoweight (21.1%). However, metabotype 0 prevalence (17.1%) was higher than that previously described (∼10%), probably due to diarrhea. This unexpected side effect reinforces the essential role of gut microbiota in ellagitannin metabolism. Besides, despite cultural and ethnical differences between Europeans and Brazilians, their gut microbiota composition may be similar in terms of ellagitannin metabolism.
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tea is a significant dietary source of Ellagitannins and ellagic acid
Journal of Agricultural and Food Chemistry, 2019Co-Authors: Xiao Yang, Francisco A TomasbarberanAbstract:The ellagitannin composition and the total content of Ellagitannins in different types of tea were studied by high-performance liquid chromatography/ion-trap mass spectrometry. Strictinin and seven other isomers, tellimagrandin I, and ellagic acid were identified from tea infusions. The ellagitannin content in tea infusions was determined after acid hydrolysis and ranged from 0.15 to 4.46 mg of ellagic acid equivalent/g of tea in the infusions. The intake of ellagic acid after drinking a cup of tea brewed with 4 g of tea could range between 0.59 and 17.89 mg. These results indicate that tea can be a significant contributor to the dietary intake of Ellagitannins. Urolithins, the gut microbiota metabolites produced in vivo from ellagic acid and Ellagitannins, were detected in human urine after dietary tea beverage intake. Urolithin metabotypes A, B, and 0 were identified in volunteers after tea intake. These results suggest that the daily intake of Ellagitannins from tea can have a role in tea health effects.
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chromatographic and spectroscopic characterization of urolithins for their determination in biological samples after the intake of foods containing Ellagitannins and ellagic acid
Journal of Chromatography A, 2016Co-Authors: Rocio Garciavillalba, Juan Carlos Espin, Francisco A TomasbarberanAbstract:Abstract Ellagitannins and ellagic acid (EA) are metabolized by the gut microbiota to produce urolithins that could be responsible for the health effects attributed to ellagitannin-containing food products. Several urolithin aglycones could be present in fecal samples while glucuronide and sulphate conjugates are mainly found in plasma and urine. So far, the lack of available standards has made difficult their correct identification and quantification. In the present study, UV and MS spectra characteristics of urolithins and their phase II metabolites have been determined using different systems based on liquid chromatography (LC) coupled with diode-array or mass spectrometer detectors with different analyzers (triple quadrupole (QqQ) and quadrupole time-of-flight (QTOF)). Chromatographic separation was achieved on a reversed-phase Poroshell C18 column (3 × 100 mm, 2.7 μm). Elution order, characteristic UV spectra, and relative response factors (RRFs) with respect to their parental compound (EA) and the most common metabolite urolithin A (Uro-A) were determined. This contribution, along with the most important mass spectra characteristics (MRM transitions, qualifier/quantifier ratio, accurate mass and fragmentation pattern) will allow the determination of urolithin metabolites in different biological samples and their quantification even if not all metabolites are commercially available. The methods developed in the three systems have been fully validated in terms of linearity, sensitivity, precision, recovery, matrix effect, selectivity and stability. After that, they were successfully applied to complex biological matrices (urine, feces and plasma) from two human studies in which volunteers consumed ellagitannin-containing foods, such as walnuts and pomegranate extracts.
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metabolism of oak leaf Ellagitannins and urolithin production in beef cattle
Journal of Agricultural and Food Chemistry, 2012Co-Authors: Rocio Gonzalezbarrio, Rocio Garciavillalba, Juan Carlos Espin, Pilar Truchado, Gonzalo Hervas, Pilar Frutos, Francisco A TomasbarberanAbstract:Oak leaves have a high concentration of Ellagitannins. These phytochemicals can be beneficial or poisonous to animals. Beef cattle are often intoxicated by oak leaf consumption, particularly after suffering feed restriction. The severity of the poisoning has recently been associated with the ruminal microbiota, as different bacterial populations were found in animals that tolerated oak leaves and in those that showed clinical and pathological signs of toxicity. Intoxication has previously been linked to the production of phenolic metabolites, particularly catechol, phloroglucinol, and resorcinol. This suggested that the microbial metabolism of Ellagitannins could also be associated with its tolerance or intoxication in different animals. Therefore, it is essential to understand the metabolism of Ellagitannins in cattle. Here we show that Ellagitannins are metabolized in the cattle rumen to urolithins. Different urolithins were detected in ruminal fluid, feces, urine, and plasma. Oak leaf Ellagitannins dec...
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Ellagitannins ellagic acid and vascular health
Molecular Aspects of Medicine, 2010Co-Authors: Mar Larrosa, Juan Carlos Espin, Maria Teresa Garciaconesa, Francisco A TomasbarberanAbstract:Abstract Hydrolysable tannins are phenolic phytochemicals that show high antioxidant and free-radical scavenging activities. For this reason their potential effects preventing oxidative related diseases, such as cardiovascular diseases, have been largely studied. In vitro studies show that Ellagitannins, at concentrations in the range 10–100 μM, show some relevant anti-atherogenic, anti-thrombotic, anti-inflammatory and anti-angiogenic effects, supporting the molecular mechanisms for the vascular health benefits. While there is good evidence supporting the vascular effects in vitro , the evidence on animal models or humans is much scarcer. The in vitro results often do not match the findings in the in vivo studies. This could be explained by the low bioavailability of the antioxidant Ellagitannins and ellagic acid. The main ellagitannin metabolites circulating in plasma are ellagic acid microbiota metabolites known as urolithins, and they have lost their free-radical scavenging activity. They are present in plasma as glucuronide or sulphate conjugates, at concentrations in the nM range. Future studies should focus in the bioavailable metabolites, urolithins, and in the form (conjugated with glucuronic acid or sulphate) and concentrations (nM range) in which they are found in plasma. In this review we critically discuss the role of Ellagitannins and ellagic acid on vascular health.
Juha-pekka Salminen - One of the best experts on this subject based on the ideXlab platform.
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Ellagitannins with Glucopyranose Cores Have Higher Affinities to Proteins than Acyclic Ellagitannins by Isothermal Titration Calorimetry.
Journal of Agricultural and Food Chemistry, 2019Co-Authors: Maarit Karonen, Marianne Oraviita, Irene Mueller-harvey, Juha-pekka Salminen, Rebecca J. GreenAbstract:The thermodynamics of the interactions of different Ellagitannins with two proteins, namely, bovine serum albumin (BSA) and gelatin, were studied by isothermal titration calorimetry. Twelve individual Ellagitannins, including different monomers, dimers, and a trimer, were used. The studies showed that several structural features affected the interaction between the ellagitannin and the protein. The interactions of Ellagitannins with proteins were stronger with gelatin than with BSA. The ellagitannin–gelatin interactions contained both the primary stronger and the secondary weaker binding sites. The ellagitannin–BSA interactions showed very weak secondary interactions. The Ellagitannins with glucopyranose cores had stronger interaction than C-glycosidic Ellagitannins with both proteins. In addition, the observed enthalpy change increased as the degree of oligomerization increased. The stronger interactions were also observed with free galloyl groups in the ellagitannin structure and with higher molecular f...
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Ellagitannins from the Onagraceae Decrease the Performance of Generalist and Specialist Herbivores
Journal of Chemical Ecology, 2019Co-Authors: Daniel N. Anstett, Juha-pekka Salminen, Iris Cheval, Caitlyn D’souza, Marc T. J. JohnsonAbstract:Phenolics have a role in defenses against herbivores, but the defensive functions of specific groups of phenolics are still poorly understood. For example, Ellagitannins (a type of hydrolyzable tannin) are predicted to decrease insect herbivore performance, but the effect of different types of Ellagitannins on generalist and specialist herbivores has rarely been assessed. Here, we test the effects of the dominant oligomeric Ellagitannins of Oenothera biennis and other Onagraceae on herbivore performance. We fed artificial diets containing between 1 and 100 mg/g of polyphenol fractions comprised of varying amounts and compositions of dimeric oenothein B, the trimeric oenothein A and larger oligomers, to one generalist ( Spodoptera exigua) and one specialist ( Schinia florida ) insect herbivore species. We compared the effects of these ellagitannin fractions on herbivore performance to the effects of artificial diet containing total phenolic extracts from O. biennis , which contained these Ellagitannins as well as many additional phenolic metabolites including flavonoid glycosides and caffeic acid derivatives. Both the ellagitannin fractions and O. biennis phenolic extracts had strong negative effects on S. exigua and S. florida performance, with stronger effects on the generalist herbivore. Differences between the effects of the various ellagitannin fractions were small and depended on insect life stage. The defensive effects of these Ellagitannins were large, with lethal concentrations as low as 0.1% of the diet. These results highlight the important defensive function of Ellagitannins against specialist and generalist herbivores and the need to characterize the effects of these understudied phenolics.
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Variability in Foliar Ellagitannins of Hippophaë rhamnoides L. and Identification of a New Ellagitannin, Hippophaenin C
Journal of Agricultural and Food Chemistry, 2018Co-Authors: Jussi Suvanto, Maarit Karonen, Petri Tähtinen, Saku Valkamaa, Marica T. Engström, Juha-pekka SalminenAbstract:Berries of common sea-buckthorn (Hippophae rhamnoides L.) are well-known and used for their bioactive components, and while there is a considerable amount of research on the leaves as well, their Ellagitannins (ETs) have not been a prominent focus of research. We identified and quantified ten major hydrophilic polyphenols, all ETs, in H. rhamnoides leaves and compared their abundance between 58 plant individuals. Of these compounds, hippophaenin C was characterized as a new ellagitannin by various spectrometric methods. The total concentrations of ETs ranged from 42.5 mg g–1 dry weight (DW) to 109.1 mg g–1 DW between individual plants. Among the ETs, hippophaenin C, stachyurin, and casuarinin were on average the most abundant compounds. Sexes did not differ significantly, while cultivars showed variation in some ETs. These results suggest that H. rhamnoides leaves could be a potential and rich source of several ETs.
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biological activity of Ellagitannins effects as anti oxidants pro oxidants and metal chelators
Phytochemistry, 2016Co-Authors: Johanna Moilanen, Maarit Karonen, Stephane Quideau, Petri Tähtinen, Remi Jacquet, Juha-pekka SalminenAbstract:Ellagitannins are a subclass of hydrolysable tannins that have been suggested to function as defensive compounds of plants against herbivores. However, it is known that the conditions in the digestive tracts of different herbivores are variable, so it seems reasonable to anticipate that the reactivities and modes of actions of these ingested defensive compounds would also be different. A previous study on a few Ellagitannins has shown that these polyphenolic compounds are highly oxidizable at high pH and that their bioactivity can be attributed to certain structural features. Herein, the activities of 13 Ellagitannins using the deoxyribose assay were measured. The results provided information about the anti-oxidant, pro-oxidant and metal chelating properties of Ellagitannins. Surprisingly, many of the tested Ellagitannins exhibited pro-oxidant activities even at neutral pH and only moderate to low radical scavenging activities, although the metal chelating capacities of all tested Ellagitannins were relatively high.
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distribution and content of Ellagitannins in finnish plant species
Phytochemistry, 2015Co-Authors: Johanna Moilanen, Piia Koskinen, Juha-pekka SalminenAbstract:Abstract The results of a screening study, in which a total of 82 Finnish plant species were studied for their ellagitannin composition and content, are presented. The total ellagitannin content was determined by HPLC-DAD, the detected Ellagitannins were further characterized by HPLC-ESI-QTOF-MS and divided into four structurally different sub-groups. Thirty plant species were found to contain Ellagitannins and the ellagitannin content in the crude extracts varied from few mg g −1 to over a hundred mg g −1 . Plant families that were rich in Ellagitannins (>90 mg g −1 of the crude extract) were Onagraceae, Lyhtraceae, Geraniaceae, Elaeagnaceae, Fagaceae and some species from Rosaceae. Plant species that contained moderate amounts of Ellagitannins (31–89 mg g −1 of the crude extract) were representatives of the family Rosaceae. Plant species that contained low amounts of Ellagitannins (1–30 mg g −1 of the crude extract) were representatives of the families Betulaceae and Myricaceae. The specific ellagitannin composition of the species allowed their chemotaxonomic classification and the comparison between the older Cronquist’s classification and the nowadays preferred Angiosperm Phylogeny Group classification.
Pierre-louis Teissedre - One of the best experts on this subject based on the ideXlab platform.
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Hydrolyzable Tannins: Gallotannins and Ellagitannins 64
2020Co-Authors: Michael Jourdes, Pierre-louis Teissedre, Denis Deffieux, Stephane QuideauAbstract:The structural diversity displayed by these gallic acid metabolites is comparable to that of other classes of plant secondary metabolites such as alkaloids and terpenoids. The first aim of this chapter is to provide a condensate the state-ofthe art on ellagitannin natural products and their significance as plant secondary metabolites, as well as interesting leads in the continuous search of new pharmaceutical drugs with original structural features. The following sections of this chapter will address research performed on C-glucosidic Ellagitannins subclass over the last decade and will, in particular focus on their implication in wine chemistry as well as their putative role as active principles in traditional herbal remedies to their potential applications in more conventional medicinal approaches.
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Variations in oxygen and Ellagitannins, and organoleptic properties of red wine aged in French oak barrels classified by a near infrared system
Food Chemistry, 2016Co-Authors: Julien Michel, Warren Albertin, Alexandra Le Floch, Thomas Giordanengo, Nicolas Mourey, Michael Jourdes, Pierre-louis TeissedreAbstract:Abstract During wine aging in barrels, antioxidant molecules from wood, such as Ellagitannins, are solubilized and react with wine molecules and oxygen. However, their concentrations are highly variable. Oxygen is an important factor, as it plays a role in wine parameters and organoleptic perceptions. Five barrel modalities were used; three polyphenol indices (IP), classified using the NIRS procedure, and three grain qualities. Barrels were equipped with windows to measure the oxygen using luminescence technology. The ellagitannin concentrations in the wine and its organoleptic properties were monitored. Oxygen concentrations decreased quickly during the first 8 days of aging and this phenomenon was significantly more marked in barrels with a higher IP and medium grain. The ellagitannin concentrations were believed to be correlated with wood classification and oxygen consumption. Furthermore, the organoleptic properties were significantly impacted, as the wine with the lowest ellagitannin level was described as less astringent, bitter, woody, and smoky/toasty.
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Compositional and sensory characterization of grape proanthocyanidins and oak wood ellagitannin
Tetrahedron, 2015Co-Authors: Kleopatra Chira, Alexandra Le Floch, Michael Jourdes, Liming Zeng, Laurent Pechamat, Pierre-louis TeissedreAbstract:Abstract Aimed at increasing our knowledge on the astringency of sensory-active non-volatile compounds migrating principally from grapes and from oak wood into the wine, grape extracts and an aqueous ethanolic extract from oak wood chips were used for their key taste compounds. Monomeric/oligomeric and polymeric proanthocyanidin fraction of seed and skin extracts were obtained from grapes. Ellagitannins were extracted and purified from oak wood. Compositional characterization, purity and sensory evaluation of grape extracts were performed by liquid chromatography/mass spectrometry and sensory analysis, respectively. Purification of ellagitannin extract at 93.4% was realized by successive fractionations on Toyopearl TSK HW-40 (F) and on C-18 column. At the same concentration, ellagitannin fraction was perceived rather mellow, seed and skin monomeric/oligomeric fraction was characterized slight astringent, polymeric seed fraction was identified as tannic whereas polymeric skin fraction was appreciated rather mellow.
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influence of wood barrels classified by nirs on the ellagitannin content composition and on the organoleptic properties of wine
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Julien Michel, Alexandra Le Floch, Thomas Giordanengo, Nicolas Mourey, Michael Jourdes, Pierre-louis TeissedreAbstract:Ellagitannins are extracted from oak wood during wine aging in oak barrels. This research is based on the NIRS (Oakscan) oak wood classification according to their index polyphenolic (IP) (between 21.07 and 70.15). Their level in wood is very variable (between 5.95 and 32.91 mg/g dry wood) and influenced their concentration in red wine (between 2.30 and 32.56 mg/L after 24 months of aging) and thus their impact on wine organoleptic properties. The results show a good correlation between the NIRS classification and the chemical analysis (HPLC-UV-MS and acidic hydrolysis procedure) and with the wood ellagitannin level, the ellagitannin extraction kinetic, and the Ellagitannins evolution in red wine (Cabernet Sauvignon). Moreover, a correlation between the NIRS classification and the increasing intensity of some wood aromas (woody, spicy, vanilla, and smoked/toasted), flavors (bitterness and astringency), and a decreasing intensity of fruitiness was also observed.
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Influence of Wood Barrels Classified by NIRS on the Ellagitannin Content/Composition and on the Organoleptic Properties of Wine
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Julien Michel, Alexandra Le Floch, Thomas Giordanengo, Nicolas Mourey, Michael Jourdes, Pierre-louis TeissedreAbstract:Ellagitannins are extracted from oak wood during wine aging in oak barrels. This research is based on the NIRS (Oakscan) oak wood classification according to their index polyphenolic (IP) (between 21.07 and 70.15). Their level in wood is very variable (between 5.95 and 32.91 mg/g dry wood) and influenced their concentration in red wine (between 2.30 and 32.56 mg/L after 24 months of aging) and thus their impact on wine organoleptic properties. The results show a good correlation between the NIRS classification and the chemical analysis (HPLC-UV-MS and acidic hydrolysis procedure) and with the wood ellagitannin level, the ellagitannin extraction kinetic, and the Ellagitannins evolution in red wine (Cabernet Sauvignon). Moreover, a correlation between the NIRS classification and the increasing intensity of some wood aromas (woody, spicy, vanilla, and smoked/toasted), flavors (bitterness and astringency), and a decreasing intensity of fruitiness was also observed.
Michael Jourdes - One of the best experts on this subject based on the ideXlab platform.
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Hydrolyzable Tannins: Gallotannins and Ellagitannins 64
2020Co-Authors: Michael Jourdes, Pierre-louis Teissedre, Denis Deffieux, Stephane QuideauAbstract:The structural diversity displayed by these gallic acid metabolites is comparable to that of other classes of plant secondary metabolites such as alkaloids and terpenoids. The first aim of this chapter is to provide a condensate the state-ofthe art on ellagitannin natural products and their significance as plant secondary metabolites, as well as interesting leads in the continuous search of new pharmaceutical drugs with original structural features. The following sections of this chapter will address research performed on C-glucosidic Ellagitannins subclass over the last decade and will, in particular focus on their implication in wine chemistry as well as their putative role as active principles in traditional herbal remedies to their potential applications in more conventional medicinal approaches.
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Variations in oxygen and Ellagitannins, and organoleptic properties of red wine aged in French oak barrels classified by a near infrared system
Food Chemistry, 2016Co-Authors: Julien Michel, Warren Albertin, Alexandra Le Floch, Thomas Giordanengo, Nicolas Mourey, Michael Jourdes, Pierre-louis TeissedreAbstract:Abstract During wine aging in barrels, antioxidant molecules from wood, such as Ellagitannins, are solubilized and react with wine molecules and oxygen. However, their concentrations are highly variable. Oxygen is an important factor, as it plays a role in wine parameters and organoleptic perceptions. Five barrel modalities were used; three polyphenol indices (IP), classified using the NIRS procedure, and three grain qualities. Barrels were equipped with windows to measure the oxygen using luminescence technology. The ellagitannin concentrations in the wine and its organoleptic properties were monitored. Oxygen concentrations decreased quickly during the first 8 days of aging and this phenomenon was significantly more marked in barrels with a higher IP and medium grain. The ellagitannin concentrations were believed to be correlated with wood classification and oxygen consumption. Furthermore, the organoleptic properties were significantly impacted, as the wine with the lowest ellagitannin level was described as less astringent, bitter, woody, and smoky/toasty.
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Compositional and sensory characterization of grape proanthocyanidins and oak wood ellagitannin
Tetrahedron, 2015Co-Authors: Kleopatra Chira, Alexandra Le Floch, Michael Jourdes, Liming Zeng, Laurent Pechamat, Pierre-louis TeissedreAbstract:Abstract Aimed at increasing our knowledge on the astringency of sensory-active non-volatile compounds migrating principally from grapes and from oak wood into the wine, grape extracts and an aqueous ethanolic extract from oak wood chips were used for their key taste compounds. Monomeric/oligomeric and polymeric proanthocyanidin fraction of seed and skin extracts were obtained from grapes. Ellagitannins were extracted and purified from oak wood. Compositional characterization, purity and sensory evaluation of grape extracts were performed by liquid chromatography/mass spectrometry and sensory analysis, respectively. Purification of ellagitannin extract at 93.4% was realized by successive fractionations on Toyopearl TSK HW-40 (F) and on C-18 column. At the same concentration, ellagitannin fraction was perceived rather mellow, seed and skin monomeric/oligomeric fraction was characterized slight astringent, polymeric seed fraction was identified as tannic whereas polymeric skin fraction was appreciated rather mellow.
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influence of wood barrels classified by nirs on the ellagitannin content composition and on the organoleptic properties of wine
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Julien Michel, Alexandra Le Floch, Thomas Giordanengo, Nicolas Mourey, Michael Jourdes, Pierre-louis TeissedreAbstract:Ellagitannins are extracted from oak wood during wine aging in oak barrels. This research is based on the NIRS (Oakscan) oak wood classification according to their index polyphenolic (IP) (between 21.07 and 70.15). Their level in wood is very variable (between 5.95 and 32.91 mg/g dry wood) and influenced their concentration in red wine (between 2.30 and 32.56 mg/L after 24 months of aging) and thus their impact on wine organoleptic properties. The results show a good correlation between the NIRS classification and the chemical analysis (HPLC-UV-MS and acidic hydrolysis procedure) and with the wood ellagitannin level, the ellagitannin extraction kinetic, and the Ellagitannins evolution in red wine (Cabernet Sauvignon). Moreover, a correlation between the NIRS classification and the increasing intensity of some wood aromas (woody, spicy, vanilla, and smoked/toasted), flavors (bitterness and astringency), and a decreasing intensity of fruitiness was also observed.
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Influence of Wood Barrels Classified by NIRS on the Ellagitannin Content/Composition and on the Organoleptic Properties of Wine
Journal of Agricultural and Food Chemistry, 2013Co-Authors: Julien Michel, Alexandra Le Floch, Thomas Giordanengo, Nicolas Mourey, Michael Jourdes, Pierre-louis TeissedreAbstract:Ellagitannins are extracted from oak wood during wine aging in oak barrels. This research is based on the NIRS (Oakscan) oak wood classification according to their index polyphenolic (IP) (between 21.07 and 70.15). Their level in wood is very variable (between 5.95 and 32.91 mg/g dry wood) and influenced their concentration in red wine (between 2.30 and 32.56 mg/L after 24 months of aging) and thus their impact on wine organoleptic properties. The results show a good correlation between the NIRS classification and the chemical analysis (HPLC-UV-MS and acidic hydrolysis procedure) and with the wood ellagitannin level, the ellagitannin extraction kinetic, and the Ellagitannins evolution in red wine (Cabernet Sauvignon). Moreover, a correlation between the NIRS classification and the increasing intensity of some wood aromas (woody, spicy, vanilla, and smoked/toasted), flavors (bitterness and astringency), and a decreasing intensity of fruitiness was also observed.
Juan Carlos Espin - One of the best experts on this subject based on the ideXlab platform.
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chromatographic and spectroscopic characterization of urolithins for their determination in biological samples after the intake of foods containing Ellagitannins and ellagic acid
Journal of Chromatography A, 2016Co-Authors: Rocio Garciavillalba, Juan Carlos Espin, Francisco A TomasbarberanAbstract:Abstract Ellagitannins and ellagic acid (EA) are metabolized by the gut microbiota to produce urolithins that could be responsible for the health effects attributed to ellagitannin-containing food products. Several urolithin aglycones could be present in fecal samples while glucuronide and sulphate conjugates are mainly found in plasma and urine. So far, the lack of available standards has made difficult their correct identification and quantification. In the present study, UV and MS spectra characteristics of urolithins and their phase II metabolites have been determined using different systems based on liquid chromatography (LC) coupled with diode-array or mass spectrometer detectors with different analyzers (triple quadrupole (QqQ) and quadrupole time-of-flight (QTOF)). Chromatographic separation was achieved on a reversed-phase Poroshell C18 column (3 × 100 mm, 2.7 μm). Elution order, characteristic UV spectra, and relative response factors (RRFs) with respect to their parental compound (EA) and the most common metabolite urolithin A (Uro-A) were determined. This contribution, along with the most important mass spectra characteristics (MRM transitions, qualifier/quantifier ratio, accurate mass and fragmentation pattern) will allow the determination of urolithin metabolites in different biological samples and their quantification even if not all metabolites are commercially available. The methods developed in the three systems have been fully validated in terms of linearity, sensitivity, precision, recovery, matrix effect, selectivity and stability. After that, they were successfully applied to complex biological matrices (urine, feces and plasma) from two human studies in which volunteers consumed ellagitannin-containing foods, such as walnuts and pomegranate extracts.
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validated method for the characterization and quantification of extractable and nonextractable Ellagitannins after acid hydrolysis in pomegranate fruits juices and extracts
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Rocio Garciavillalba, Marina Heinonen, Juan Carlos Espin, Kjersti Aaby, Cesarettin Alasalvar, Griet Jacobs, Stefan Voorspoels, Tuuli Koivumaki, Paul A Kroon, Ebru PelvanAbstract:Pomegranates are one of the main highly valuable sources of Ellagitannins. Despite the potential health benefits of these compounds, reliable data on their content in pomegranates and derived extracts and food products is lacking, as it is usually underestimated due to their complexity, diversity, and lack of commercially available standards. This study describes a new method for the analysis of the extractable and nonextractable Ellagitannins based on the quantification of the acid hydrolysis products that include ellagic acid, gallic acid, sanguisorbic acid dilactone, valoneic acid dilactone, and gallagic acid dilactone in pomegranate samples. The study also shows the occurrence of ellagitannin C-glycosides in pomegranates. The method was optimized using a pomegranate peel extract. To quantify nonextractable Ellagitannins, freeze-dried pomegranate fruit samples were directly hydrolyzed with 4 M HCl in water at 90 °C for 24 h followed by extraction of the pellet with dimethyl sulfoxide/methanol (50:50, v...
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metabolism of oak leaf Ellagitannins and urolithin production in beef cattle
Journal of Agricultural and Food Chemistry, 2012Co-Authors: Rocio Gonzalezbarrio, Rocio Garciavillalba, Juan Carlos Espin, Pilar Truchado, Gonzalo Hervas, Pilar Frutos, Francisco A TomasbarberanAbstract:Oak leaves have a high concentration of Ellagitannins. These phytochemicals can be beneficial or poisonous to animals. Beef cattle are often intoxicated by oak leaf consumption, particularly after suffering feed restriction. The severity of the poisoning has recently been associated with the ruminal microbiota, as different bacterial populations were found in animals that tolerated oak leaves and in those that showed clinical and pathological signs of toxicity. Intoxication has previously been linked to the production of phenolic metabolites, particularly catechol, phloroglucinol, and resorcinol. This suggested that the microbial metabolism of Ellagitannins could also be associated with its tolerance or intoxication in different animals. Therefore, it is essential to understand the metabolism of Ellagitannins in cattle. Here we show that Ellagitannins are metabolized in the cattle rumen to urolithins. Different urolithins were detected in ruminal fluid, feces, urine, and plasma. Oak leaf Ellagitannins dec...
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Ellagitannins ellagic acid and vascular health
Molecular Aspects of Medicine, 2010Co-Authors: Mar Larrosa, Juan Carlos Espin, Maria Teresa Garciaconesa, Francisco A TomasbarberanAbstract:Abstract Hydrolysable tannins are phenolic phytochemicals that show high antioxidant and free-radical scavenging activities. For this reason their potential effects preventing oxidative related diseases, such as cardiovascular diseases, have been largely studied. In vitro studies show that Ellagitannins, at concentrations in the range 10–100 μM, show some relevant anti-atherogenic, anti-thrombotic, anti-inflammatory and anti-angiogenic effects, supporting the molecular mechanisms for the vascular health benefits. While there is good evidence supporting the vascular effects in vitro , the evidence on animal models or humans is much scarcer. The in vitro results often do not match the findings in the in vivo studies. This could be explained by the low bioavailability of the antioxidant Ellagitannins and ellagic acid. The main ellagitannin metabolites circulating in plasma are ellagic acid microbiota metabolites known as urolithins, and they have lost their free-radical scavenging activity. They are present in plasma as glucuronide or sulphate conjugates, at concentrations in the nM range. Future studies should focus in the bioavailable metabolites, urolithins, and in the form (conjugated with glucuronic acid or sulphate) and concentrations (nM range) in which they are found in plasma. In this review we critically discuss the role of Ellagitannins and ellagic acid on vascular health.
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iberian pig as a model to clarify obscure points in the bioavailability and metabolism of Ellagitannins in humans
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Juan Carlos Espin, Rocio Gonzalezbarrio, Begona Cerda, C J Lopezbote, Francisco A TomasbarberanAbstract:Ellagitannin-containing foods (strawberries, walnuts, pomegranate, raspberries, oak-aged wine, etc.) have attracted attention due to their cancer chemopreventive, cardioprotective, and antioxidant effects. Ellagitannins (ETs) are not absorbed as such but are metabolized by the intestinal flora to yield urolithins (hydroxydibenzopyran-6-one derivatives). In this study, Iberian pig is used as a model to clarify human ET metabolism. Pigs were fed either cereal fodder or acorns, a rich source of ETs. Plasma, urine, bile, lumen and intestinal tissues (jejunum and colon), feces, liver, kidney, heart, brain, lung, muscle, and subcutaneous fat tissue were analyzed. The results demonstrate that acorn ETs release ellagic acid (EA) in the jejunum, then the intestinal flora metabolizes EA sequentially to yield tetrahydroxy- (urolithin D), trihydroxy- (urolithin C), dihydroxy- (urolithin A), and monohydroxy- (urolithin B) dibenzopyran-6-one metabolites, which were absorbed preferentially when their lipophilicity incre...