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Silkworm (Bombyx mori) pupae is a by-product from the silk industry which is rich in protein. Hydrolysates from silkworm pupae generated using Alcalase®, Prolyve®, Flavourzyme® and Brewers Clarex® proteolytic prepa- rations were characterised. The antioxidant activity of the hydrolysates was investigated using in vitro antioxi- dant assays and an in situ assay for reactive oxygen species (ROS) reduction using hepatic HepG2. Overall, Alcalase and Prolyve hydrolysates had highest scavenging activities, however, Flavourzyme and Brewers Clarex hydrolysates had enhanced ferric reducing antioxidant power (FRAP) activity compared to the other samples. Furthermore, the Flavourzyme hydrolysate significantly reduced ROS by 40% compared to untreated control HepG2 cells. Peptides identified by LC-MS/MS were synthetised and then tested for their in vitro and in situ antioxidant activity. Peptides SWFVTPF and NDVLFF showed highest antioxidant activity (ROS reduction, su- peroxide dismutase (SOD) expression and glutathione (GSH) production activity) in HepG2 cells, and therefore may have potential as natural antioxidants.

peer-reviewed, no abstract available, PUBLISHED, peer-reviewed

peer-reviewed, Four different types of ginger cakes, two according to the traditional making process and two others according to the new recipes, were baked at 180 °C for 18 min. Ginger cakes formulated according to the new recipe (mixed wheat/rye flours) showed lower antioxidant capacity by 70% than traditional cakes formulated on dark or brown rye flour. The traditional ginger cakes were a better source of extractable phenolics than the newly formulated ones. The average contents of extractable total phenolic compounds in traditional ginger cakes were about 48% higher compared to those found in new ones. The formulation and making process improved antioxidant properties of ginger cakes and generated a significant amount of Maillard reaction products. Application of new recipes improved nutritional quality of ginger cakes due to a higher protein quantity and lesser contents of components potentially harmful to human health. Based on the higher protein quality and chemical data, ginger cakes formulated according to new recipes should be preferred with the aim to lower the intake of dietary advanced glycation end products., PUBLISHED, peer-reviewed

peer-reviewed, Milk protein derived peptides have numerous well-documented bioactive properties. The conventional approach for the generation, identification and validation of bioactive peptides (BAPs) has involved (i) protein hydrolysis, (ii) bioactivity screening and (iii) validation in vivo. The low potency (in comparison to conventional drugs), susceptibility to breakdown during gastrointestinal transit and low intestinal permeability are key challenges in the development of highly bioactive food protein hydrolysates/peptides. However, the generation of potent and effective health enhancing hydrolysates/peptides can benefit from a range of in silico techniques including the application of structure bioactivity relationship modelling (e.g., quantitative structure activity relationship (QSAR) modelling), molecular docking and design of experiments (DOE) approaches to optimise BAP production and identification. Some examples of how these approaches have been employed in BAP discovery and generation will be outlined., PUBLISHED, peer-reviewed

peer-reviewed, Individual amino acids, amino acid mixtures and protein hydrolysates stimulate glucose uptake in many experimental models. To replicate better in vitro the dynamic postprandial response to feeding in vivo, in the present study we investigated the effects of culture media conditioned with fasted and postprandial human serum on GLUT4 translocation in L6‐GLUT4myc myotubes. Serum samples were collected from healthy male participants (n = 8) at baseline (T0), 60 (T60) and 120 min (T120) after the ingestion of 0.33 g (kg body mass)−1 of intact (WPC) or hydrolysed (WPH) whey protein and an isonitrogenous non‐essential amino acid (NEAA) control. L6‐GLUT4myc myotubes were starved of serum and amino acids for 1 h before incubation for 1 h in medium containing 1% postprandial human serum, after which GLUT4 translocation was determined via colorimetric assay. Medium conditioned with fasted human serum at concentrations of 5–20% increased cell surface GLUT4myc abundance. Incubation with serum collected after the ingestion of WPH increased cell surface GLUT4myc at T60 relative to T0 [mean (lower, upper 95% confidence interval)]; [1.13 (1.05, 1.22)], whereas WPC [0.98 (0.90, 1.07)] or NEAA [1.02 (0.94, 1.11)] did not. The differential increases in cell surface GLUT4myc abundance were not explained by differences in serum concentrations of total, essential and branched‐chain amino acids or insulin, glucagon‐like peptide 1 (GLP‐1) and gastric inhibitory polypeptide (GIP). Using a new ex vivo, in vitro approach, cell culture medium conditioned with postprandial serum after the ingestion of a whey protein hydrolysate increased GLUT4 translocation in skeletal muscle cells., ACCEPTED, peer-reviewed

Red grape pomace (RGP) is a major winery by-product with interesting applications due to its high phenolic content and antioxidant capacity. Effects of in vitro gastrointestinal digestion and storage on the phenolic content and antioxidant capacity of RGP were studied. RGP polyphenols were stable under stomach-mimicking conditions and more sensitive to small intestine conditions, reducing anthocyanins and flavonols. After 3- and 6-month storage, at either 4 or 25 °C, there were no changes in the total phenolic and condensed tannin content, or antioxidant capacity (evaluated by ABTS, FRAP, ORAC assays); however, after 9 months these parameters decreased. Contrarily, chromatic b* values were higher, thus the samples had more intense red color, which may be related to the increased condensed tannin content. Storage time or temperature induced no changes in microbiological load. RGP preserves high antioxidant capacity after storage and in vitro digestion and thus presents potential as a functional ingredient or nutraceutical.

Estudios epidemiológicos han mostrado repetidamente un asociación inversa entre el riesgo de enfermedades crónicas y el consumo de una dieta rica en compuestos fenólicos. La uva es uno de los cultivos de mayor producción hortofrutícola en el mundo, siendo un alimento muy rico en polifenoles. Su empleo en la elaboración de vino produce una gran cantidad de subproductos de uva, con un alto contenido en polifenoles, principalmente antocianos (en uva tinta), catequinas, glicósidos de flavonoles, ácidos y alcoholes fenólicos y estilbenos. Por tanto, los subproductos de uva son una importante fuente de antioxidantes fenólicos, siendo importante evaluar sus propiedades biológicas para profundizar en el conocimiento del potencial de este producto como ingrediente funcional o nutracéutico. La yerba mate y el café destacan entre las bebidas más populares mundialmente. El café verde y el mate tienen una composición fenólica similar. El café verde contiene ácidos clorogénicos, cinamoil amidas y glicósidos y ácidos fenólicos libres, mientras que la yerba mate además de estos ácidos hidroxicinámicos contiene flavonoles como la rutina y otros glicósidos de flavonoles. Además de su creciente consumo como ingredientes en nutracéuticos, el mate es ampliamente consumido como infusión, mientras que la ingesta de café verde como infusión o en mezcla con café tostado está incrementando en los últimos años como una alternativa más saludable al café tostado. Las propiedades biológicas de los flavonoides han sido extensivamente estudiadas; asimismo, en los últimos años ha ganado interés y presencia en la literatura científica los estudios sobre ácidos clorogénicos. Sin embargo, otros ácidos fenólicos han sido menos estudiados in vitro e in vivo, e igualmente, los estudios sobre la actividad biológica de metabolitos circulantes son todavía muy escasos. Por otro lado, el empleo de líneas celulares inmortalizadas como modelo para el estudio de los efectos quimioprotectores de fitoquímicos, ent

Hydroxytyrosol (HT) and its derivatives in olive oil protect low-density lipoproteins (LDL) against oxidation. Biscuits could be a convenient alternative to broaden consumers' choice of HT-rich foods, although the biscuit matrix could affect HT bioavailability. We performed a crossover, randomized, double-blind study to evaluate HT bioavailability in HT-enriched biscuits (HT-B) versus non-enriched biscuits (C-B), and the effects on oxidative postprandial status. On two separate days, 13 subjects consumed 30 g of C-B or HT-B (5.25 mg HT) after overnight-fasting. Blood and urine were collected at different intervals and analysed by LC-MS-QToF. After HT-B consumption, plasma metabolites peaked between 0.5 and 1 h and were extensively excreted in urine. HT-sulphate and 3,4-dihydroxyphenylacetic acid (DOPAC)-sulphate were the main metabolites, followed by DOPAC and homovanillic acid (HVA). HT-glucuronide, DOPAC-glucuronide, HVA-glucuronide and HVA-sulphate were also detected. Postprandial oxidised-LDL concentrations decreased with HT-B. HT is a promising functional ingredient and, in biscuits, it is highly bioavailable and lowers postprandial oxidised-LDL levels.

[Introduction]: Health promoting effects associated to coffee silverskin extract (CSE) largely depend on the bioaccesibility and bioavailability of chlorogenic acid (CGA) and caffeine and it is evaluated in the present study. [Methods]: CSE was in vitro gastrointestinal digested mimicking human conditions. Bioaccesibility of CSE's compounds was assayed by analysis of proteins, total phenolic compounds (TPC), CGA, caffeine and antioxidant capacity after the in vitro digestion. CGA and caffeine in vivo bioavailability was evaluated using male Wistar rats (n=32) divided into four groups (n=8). A Control group received 1 ml of sterile water; CSE group received CSE (128 mg/kg body-weight equivalent to 0.88 mg CGA/kg body-weight and 2.55 mg caffeine/kg body-weight); CGA group received 1.5 mg CGA/kg body-weight and caffeine group received 5 mg caffeine /kg body-weight. Doses were administered diluted in 1 ml of water by gavage. Animals were housed singly in metabolic cages. Urine samples were serially collected for every 1 hour up to 6 h, then every 2 hours up to 10 h and then up to 24 h. CGA and caffeine and their major metabolites, hippuric acid and paraxanthine were determined in urine by UPLC-MS/MS analysis. [Results]: Bioaccesibility of TPC, CGA and caffeine decreased due to digestion in 39%, 80% and 25%, respectively. On the contrary, the overall antioxidant capacity of CSE remained in 82% (ABTS) and 74% (ORAC) after in vitro digestion suggesting the formation of novel antioxidant during the process. Results on bioavailability indicated caffeine was highly metabolized to paraxanthine after CSE intake while free CGA wasn't bioavailable. [Conclusions, discussion and/or practical application]: Our findings seem to indicate that CSE health effects might be linked to its antioxidant character or a synergic effect of different components present in CSE including caffeine and its metabolites, but cannot be ascribed to free CGA.

The bioaccessibility of chlorogenic acid (CGA) and caffeine in coffee silverskin extracts (CSE) and the contribution of these substances to the prophylactic effect of CSE on the pathogenesis of diabetes have not been reported. This study aimed to evaluate the bioaccessibility, bioavailability and bioactivity of CGA and caffeine alone and in CSE in the pancreas of rats treated with streptozotocin-nicotinamide (type 2 diabetes model). Metabolism of CGA and caffeine started in the gastrointestinal tract due to changes of pH taking place during digestion. Their metabolites protected pancreatic cells against the risk of diabetes. This is the first in vivo study to demonstrate a specific chemo-protective effect of CSE in pancreatic tissue, and this effect may be associated with its antioxidant capacity. Daily administration of CSE, CGA or caffeine 35 d previous to the induction of diabetes significantly reduced (p < 0.05) pancreatic oxidative stress and protein damage.