Bioavailability of black tea theaflavins: absorption, metabolism, and colonic catabolism

Data obtained with in vitro fecal incubations and a feeding study indicate black tea theaflavin and its galloyl derivatives are not absorbed in detectable amounts in either the upper or lower gastrointestinal tract. The theaflavin skeleton is comparatively resistant to degradation by colonic bacteria with a 67% recovery being obtained after a 24 h incubation, which yielded 21 phenolic and aromatic catabolites. The theaflavin galloyl moiety was removed by the microbiota, and the released gallic acid further transformed to 3-O- and 4-O-methyl gallic acids, pyrogallol-1-sulfate and pyrogallol-2-sulfate, which were excreted in urine in amounts equivalent to 94% of intake. The main urinary product potentially derived from breakdown of the theaflavin skeleton was 3-(4′-hydroxyphenyl)propionic acid. A number of the colonic catabolites originating from gallic acid and theaflavins has been reported to be bioactive in ex vivo and in vitro models with a variety of potential modes of action

Synthesis and Characterization of Elongated-Shaped Silver Nanoparticles as a Biocompatible Anisotropic SERS Probe for Intracellular Imaging: Theoretical Modeling and Experimental Verification

Progress in the field of biocompatible SERS nanoparticles has promising prospects for biomedical applications. In this work, we have developed a biocompatible Raman probe by combining anisotropic silver nanoparticles with the dye rhodamine 6G followed by subsequent coating with bovine serum albumin. This nanosystem presents strong SERS capabilities in the near infrared (NIR) with a very high (2.7 × 107) analytical enhancement factor. Theoretical calculations reveal the effects of the electromagnetic and chemical mechanisms in the observed SERS effect for this nanosystem. Finite element method (FEM) calculations showed a considerable near field enhancement in NIR. Using density functional quantum chemical calculations, the chemical enhancement mechanism of rhodamine 6G by interaction with the nanoparticles was probed, allowing us to calculate spectra that closely reproduce the experimental results. The nanosystem was tested in cell culture experiments, showing cell internalization and also proving to be completely biocompatible, as no cell death was observed. Using a NIR laser, SERS signals could be detected even from inside cells, proving the applicability of this nanosystem as a biocompatible SERS probe.España, Regional Ministry of Economy, Junta de Andalucía, P07-FQM-02595 (to CC), P10-FQM-06615 (to JMOM), P10-CTS-6928 (to DP) and PAIDI2020 Program (FQM319 to RFM and CTS677 to DP)Junta de Andalucía, PI-0070/2008 (to PZ) and PI-0068/2008 (to DP

Bioavailability of orange juice (poly)phenols: the impact of short-term cessation of training by male endurance athletes

Background: Physical exercise has been reported to increase the bioavailability of citrus flavanones. Objective: To investigate the bioavailability of orange juice (OJ) (poly)phenols in endurance-trained men before and after cessation of training for 7 days. Design: Ten fit endurance-trained males, with a maximal oxygen consumption of 58.2 ± 5.3 mL/kg/min, followed a low (poly)phenol diet for 2 d before drinking 500 mL of OJ, containing 398 µmol of (poly)phenols of which 330 µmol were flavanones. After the volunteers stopped training for 7 days the feeding study was repeated. Urine samples were collected 12 h pre- and 24 h post-OJ orange consumption. Bioavailability was assessed by the quantitative analysis of urinary flavanone metabolites and (poly)phenol catabolites using HPLC-HR-MS. Results: While training, 0-24 h urinary excretion of flavanone metabolites, mainly hesperetin-3-O-glucuronide, hesperetin-3´-sulfate, naringenin-4´-O-glucuronide, naringenin-7-O-glucuronide, was equivalent to 4.2% of OJ flavanone intake. This increased significantly to 5.2% when OJ was consumed after the volunteers stopped training for 7 days. Overall, this trend, although not significant, was also observed with OJ-derived colonic catabolites which after supplementation in the trained state were excreted in amounts equivalent to 51% of intake compared to 59% after cessation of training. However, urinary excretion of three colonic catabolites of bacterial origin, most notably, 3-(3´-hydroxy-4´-methoxyphenyl)hydracrylic acid, did increase significantly when OJ was consumed post- compared to pre-cessation of training. Data were also obtained on inter-individual variations in flavanone bioavailability. Conclusion: A 7-day cessation of endurance training enhanced, rather than reduced, the bioavailability of OJ flavanones. The biological significance of these differences and, whether or not they extend to the bioavailability of other dietary (poly)phenols, remains to be determined. Hesperetin-3´-O-glucuronide and the colonic microbiota-derived catabolite 3-(3´-hydroxy-4´-methoxyphenyl)hydracrylic acid are key biomarkers of the consumption of hesperetin-O-glycoside-containing OJ and other citrus products

Influence of coach encouragement on technical demand of an small-sided games in football-7.

El objetivo del presente estudio ha sido analizar el efecto de la motivación del entrenador sobre la demanda técnica de un juego reducido (JR) 3 contra 3, realizado por futbolistas de categoría alevín, observando el nivel de aprendizaje técnico adquirido a través de estas tareas. Se han cuantificado el número de acciones técnicas que se producen en un JR de 3 contra 3 sin intervención del entrenador (JRSIE) y las que se producen en el mismo JR con la intervención del entrenador (JRCME). Se ha realizado en cada una de las 4 sesiones del programa de entrenamiento con JR dos test de valoración del dominio técnico en situaciones pre y post sesión. Los resultados confirman que aparecen diferencias en el número de acciones técnicas que el jugador realiza durante el JR, siendo significativamente mayor en el JRCME, generándose además mayor nivel de aprendizaje

Synthesis of Hydroxytyrosyl Alkyl Ethers from Olive Oil WasteWaters

The preparation of a new type of derivatives of the naturally occurring antioxidant hydroxytyrosol is reported. Hydroxytyrosyl alkyl ethers were obtained in high yield by a three-step procedure starting from hydroxytyrosol isolated from olive oil waste waters. Preliminary results obtained by the Rancimat method have shown that these derivatives retain the high protective capacity of free hydroxytyrosol.The preparation of a new type of derivatives of the naturally occurring antioxidant hydroxytyrosol is reported. Hydroxytyrosyl alkyl ethers were obtained in high yield by a three-step procedure starting from hydroxytyrosol isolated from olive oil waste waters. Preliminary results obtained by the Rancimat method have shown that these derivatives retain the high protective capacity of free hydroxytyrosol

Identification of plasma and urinary metabolites and catabolites derived from orange juice (poly)phenols: analysis by high-performance liquid chromatography–high-resolution mass spectrometry

Orange juice is a rich source of (poly)phenols, in particular, the flavanones hesperetin-7-O-rutinoside and naringenin-7-O-rutinoside. Following the acute consumption of 500 mL of orange juice containing 398 μmol of (poly)phenols by 12 volunteers, 0–24 h plasma and urine samples were analyzed by targeted high-performance liquid chromatography–high-resolution mass spectrometry in order to identify flavanone metabolites and phenolic acid and aromatic catabolites. A total of 19 flavanone metabolites—comprising di-O-glucuronide, O-glucuronide, O-glucuronyl-sulfate, and sulfate derivatives of hesperetin, naringenin, and eriodictyol—and 65 microbial-derived phenolic catabolites, such as phenylpropanoid, phenylpropionic, phenylacetic, benzoic, and hydroxycarboxylic acids and benzenetriol and benzoylglycine derivatives, including free phenolics and phase II sulfate, glucuronide, and methyl metabolites, were identified or partially identified in plasma and/or urine samples. The data obtained provide a detailed evaluation of the fate of orange juice (poly)phenols as they pass through the gastrointestinal tract and are absorbed into the circulatory system prior to renal excretion. Potential pathways for these conversions are proposed

Aryl hydrocarbon receptor activation during in vitro and in vivo digestion of raw and cooked broccoli (brassica oleracea var. Italica)

Broccoli is rich in glucosinolates, which can be converted upon chewing and processing into Aryl hydrocarbon Receptor (AhR) ligands. Activation of AhR plays an important role in overall gut homeostasis but the role of broccoli processing on the generation of AhR ligands is still largely unknown. In this study, the effects of temperature, cooking method (steaming versus boiling), gastric pH and further digestion of broccoli on AhR activation were investigated in vitro and in ileostomy subjects. For the in vitro study, raw, steamed (t = 3 min and t = 6 min) and boiled (t = 3 min and t = 6 min) broccoli were digested in vitro with different gastric pH. In the in vivo ileostomy study, 8 subjects received a broccoli soup or a broccoli soup plus an exogenous myrosinase source. AhR activation was measured in both in vitro and in vivo samples by using HepG2-Lucia™ AhR reporter cells. Cooking broccoli reduced the AhR activation measured after gastric digestion in vitro, but no effect of gastric pH was found. Indole AhR ligands were not detected or detected at very low levels both after intestinal in vitro digestion and in the ileostomy patient samples, which resulted in no AhR activation. This suggests that the evaluation of the relevance of glucosinolates for AhR modulation in the gut cannot prescind from the way broccoli is processed, and that broccoli consumption does not necessarily produce substantial amounts of AhR ligands in the large intestine

Changes in the Organosulfur and Polyphenol Compound Profiles of Black and Fresh Onion during Simulated Gastrointestinal Digestion

This study aims to determine the changes in, and bioaccessibility of, polyphenols and organosulfur compounds (OSCs) during the simulated gastrointestinal digestion of black onion, a novel product derived from fresh onion by a combination of heat and humidity treatment, and to compare it with its fresh counterpart. Fresh and black onions were subjected to in-vitro gastrointestinal digestion, and their polyphenol and OSC profiles were determined by ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS). Although to a lesser extent than in the fresh onion, the phenolic compounds in the black variety remained stable during the digestion process, presenting a higher bioaccessibility index (BI) with recovery corresponding to 41.1%, compared with that of fresh onion (23.5%). As for OSCs, apart from being more stable after the digestion process, with a BI of 83%, significantly higher quantities (21 times higher) were found in black onion than in fresh onion, suggesting that the black onion production process has a positive effect on the OSC content. Gallic acid, quercetin, isorhamnetin, and ɣ-glutamyl-S-(1-propenyl)-L-cysteine sulfoxide were the most bioaccessible compounds in fresh onion, while isorhamnetin, quercetin-diglucoside, ɣ-glutamyl-S-methyl-L-cysteine sulfoxide and methionine sulfoxide were found in black onion. These results indicate that OSCs and polyphenols are more bioaccessible in black onion than in fresh onion, indicating a positive effect of the processing treatment

Effect of In Vitro Gastrointestinal Digestion and Colonic Fermentation on the Stability of Polyphenols in Pistachio (Pistacia Vera L.)

The aim of this study was to evaluate the impact of in vitro gastrointestinal digestion and colonic fermentation on the polyphenol compounds from different varieties of pistachio by UHPLC-HRMS analysis. The total polyphenol content decreased significantly, mostly during oral (recoveries of 27 to 50%) and gastric digestion (recoveries of 10 to 18%), with no significant changes after the intestinal phase. After in vitro digestion, the hydroxybenzoic acids and the flavan-3-ols were the main compounds found in pistachio, with respective total polyphenol contents of 73 to 78% and 6 to 11%. More specifically, the main compounds determined after in vitro digestion were 3,4,5-trihydroxybenzoic acid, vanillic hexoside and epigallocatechin gallate. The colonic fermentation affected the total phenolic content of the six varieties studied, with a recovery range of 11 to 25% after 24 h of fecal incubation. A total of twelve catabolites were identified after fecal fermentation, the main compounds being the 3-(3′-hydroxyphenyl)propanoic, 3-(4′-hydroxyphenyl)propanoic, 3-(3′,4′-dihydroxyphenyl)propanoic, 3-hydroxyphenylacetic acids and 3,4-dihydroxyphenyl-ɣ-valerolactone. Based on these data, a catabolic pathway for colonic microbial degradation of phenolic compounds is proposed. The catabolites identified at the end of the process are potentially responsible for the health properties attributed to pistachio consumption