Structure and antigenicity changes in 7S soyabean allergen by enzymic deglycosylation

peer-reviewedno abstract availablePUBLISHEDpeer-reviewe

Facts about the formation of newantioxidants in natural samples after subcritical water extraction

8 páginas, 3 figuras, 3 tablas.-- El pdf del artículo es la versión pre-print.Subcritical water extraction (SWE) is a very promising technique for obtaining bioactives (mainly antioxidants) from natural sources; even if sometimes the high operation temperatures have been suggested as responsible for thermal degradation of bioactives, the fact is that this type of extraction processes may generate new bioactive (antioxidant) compounds. The present study involved the analysis of antioxidants either naturally found in raw samples and/or those formed during extraction via Maillard reaction and other chemical events. Samples of different nature like microalgae (Chlorella vulgaris), algae (Sargassum vulgare, Porphyra spp., Cystoseira abies-marina, Sargassum muticum, Undaria pinnatifida, and Halopitys incurvus) and plants (rosemary, thyme and verbena) were studied. Amino acid availability, sugar content, fluorescence and absorbance at different wavelengths were determined to follow chemical changes due to reactions such as Maillard, caramelization and thermoxidation. Folin reaction also provided information related to total phenol content of the samples. ABTS•+, peroxyl as well as superoxide radical scavenging assays were used to measure the antioxidant capacity of the extracts. Results obtained from this study suggest that neoformed compounds derived from Maillard, caramelization and thermoxidation reactions affect the overall antioxidant capacity of water subcritical extracts depending on the nature of the sample. The brown algae U. pinnatifida was the sample in which these chemical events contributed to a higher extent to improve the antioxidant capacity (from 0.047 to 1.512 mmol/g and from 45.356 to 1522.692 μmol/g for the TEAC and ORACFL methods, respectively) when the extraction temperature was raised from 100 to 200 °C. To the best of our knowledge, this is the first work supporting the formation of neoantioxidants in natural complex matrices during subcritical water extraction.This work has been financed by AGL2008-05108-C03-01 (Ministerio de Educacion y Ciencia), CSD2007-00063 FUN-CFOOD (Programa CONSOLIDER-INGENIO 2010) and by ALIBIRD, S2009/AGR- 1469 (Comunidad de Madrid) projects. M.H. would like to thank the Spanish Science and Innovation Ministry (MICINN) for a post-doc contract (“Juan de la Cierva” programme). M.P. thanks CSIC for her I3P fellowship. M.A.B. thanks for a Danone Institute fellowship.Peer reviewe

An Investigation of the Protein Quality and Temporal Pattern of Peripheral Blood Aminoacidemia following Ingestion of 0.33 g·kg−1 Body Mass Protein Isolates of Whey, Pea, and Fava Bean in Healthy, Young Adult Men

An increase in the intake of legumes is recommended in the promotion of plant-sourced (PSP) rather than animal-sourced (ASP) protein intake to produce a more sustainable diet. This study evaluated the quality of novel PSP isolates from pea (PEA) and fava bean (FAVA) and an ASP isolate of whey (WHEY) and compared the magnitude and temporal pattern of peripheral arterial aminoacidemia following ingestion of 0.33 g·kg−1 body mass of protein isolate in healthy young adult men (n = 9). Total indispensable amino acids (IAA) comprised 58% (WHEY), 46% (PEA), and 42% (FAVA) of the total amino acid (AA) composition, with the ingested protein providing 108% (WHEY), 77% (PEA), and 67% (FAVA) of the recommended per diem requirement of IAA. Reflecting the AA composition, the area under the curve (∆AUC0-180), post-ingestion increase in total IAA for WHEY was 41% (p < 0.001) and 57% (p < 0.001) greater than PEA and FAVA, respectively, with PEA exceeding FAVA by 28% (p = 0.003). As a sole-source, single-dose meal-size serving, the lower total IAA for PEA and FAVA would likely evoke a reduced post-prandial anabolic capacity compared to WHEY. Incorporated into a food matrix, the promotion of PSP isolates contributes to a more sustainable diet.Funder: Enterprise Ireland, Innovation Partnership; FundRef: https://doi.org/10.13039/10.13039/501100001588; Grant(s): IP/2019/087

Identification of peptides from edible silkworm pupae (Bombyx mori) protein hydrolysates with antioxidant activity

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

Current knowledge on the extraction, purification, identification and validation of bioactive peptides from seaweed

peer-reviewedSeaweed (macroalgae) is considered as a sustainable bioresource rich in high-quality nutrients such as protein. Seaweed protein can be used as an alternative to other protein sources. Furthermore, these proteins are natural reservoirs of bioactive peptides (BAPs) associated with various health benefits such as antioxidant, antihypertensive and antidiabetic activities. However, seaweed derived BAPs remain underexploited due to challenges which arise during protein extraction from algal biomass. Coupled with this, limited proteomic information exists regarding certain seaweed species. This review highlights the current state of the art of seaweed protein extraction techniques, e.g., liquid, ultrasound, microwave, pulsed electric field and high hydrostatic pressure assisted extraction. The review also focuses on the enzymatic hydrolysis of seaweed proteins and characterisation of the resultant hydrolysates/peptides using electrophoretic and chromatographic techniques. This includes reference to methods employed for separation, fractionation and purification of seaweed BAPs, as well as the methodologies used for identification, e.g., analysis by mass spectrometry. Furthermore, a bioinformatics or in silico approach to aid discovery of seaweed BAPs is discussed herein. Based on the information available to date, it is suggested that further research is required in this area for the development of seaweed BAPs for nutraceutical applications

Insights on the health benefits of the bioactive compounds of coffee silverskin extract

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.This work was supported by grants from SUSCOFFEE (AGL2014-57239-R) and SAMID (RD12/0026). B. Fernandez-Gomez thanks the PhD program of MINECO for supporting her research career (BES-2011-046827). SAMID RETICS is funded by the PN I+D+I 2012-2016 (Spain), ISCIII- Sub-Directorate General for Research Assessment and Promotion and the European Regional Development Fund (ERDF), ref. RD12/0026.Peer Reviewe

PL - 033 A translational model of muscle protein synthetic bioactivity in vitro, ex vivo and in vivo

Objective The aim of this research was the development and validation of a translational model for the evaluation of exercise and nutrient stimulated muscle protein synthesis (MPS). To achieve this overall aim, three primary objectives had to be realised: (i) Development of an in vitro skeletal muscle cell bioassay to measure muscle growth and MPS; (ii) Development of an ex vivo model to evaluate the humoral effect on MPS in response to nutrient feeding and exercise; (iii) Use of a stable isotope technique to evaluate MPS in response to nutrient feeding and exercise in vivo. Methods To develop a novel in vitro skeletal muscle cell bioassay to measure muscle growth and MPS, C2C12 myoblasts were proliferated and subsequently differentiated to myotubes over 8 days in DMEM (2% HS). Changes in cell behavior and adhesion properties were monitored by measuring impedance via interdigitated microelectrodes using the xCELLigence system. MPS was measured by puromycin incorporation using the SUnSET technique, intracellular signalling measured by western blot, and myotube thickness by microscopy. To demonstrate the capability to monitor nutrient regulation of muscle growth, media was conditioned with a known potent regulator of MPS (leucine) in a dose response experiment (0.20 - 2.0 mM). To establish the ability of the bioassay to measure the humoral effect of MPS in response to feeding and exercise, media was conditioned by ex vivo human serum from fasted, rested, fed (protein and isonitrogenous non-essential amino acid (NEAA) control) &nbsp;and post-exercise conditions. To evaluate MPS in response to nutrient feeding and exercise in vivo, acute MPS (5 h) was assessed by measuring stable isotope deuterium oxide (D2O) incorporation into m. vastus lateralis skeletal muscle following consumption of either a Whey Protein (WP) or an isonitrogenous NEAA control combined with resistance exercise in resistance trained males. Results In vitro experiments observed a dose-response effect with a 32 % increase in cell index and a 27 % increase in cell thickness after 2 h in the presence of 2.0 mM leucine when compared with control myotubes. Ex vivo serum following ingestion of NEAA had no effect on protein signalling or MPS whereas WP fed serum significantly increased mTOR, P70S6K and 4E-BP1 phosphorylation (p&lt;0.01, p&lt;0.05) compared to fasted serum. Furthermore, the effect of WP fed serum on protein signalling and MPS was significantly increased (p&lt;0.01, p&lt;0.05) compared to NEAA fed serum.&nbsp; Ex vivo human serum following resistance exercise was also increased MPS (29 %) and phosphorylation of mTOR (6 %), p70S6K (12 %) and 4EBP1 (7 %), compared with resting serum. These ex vivo/in vitro findings translated to the in vivo model as myofibrillar fractional synthetic rates (myoFSR) (Basal 0.068±0.002%h-1 vs. WP 0.084±0.006 %h-1, p=0.033) and absolute synthetic rates (ASR) (Basal 10.34±1.01 vs. WP 13.18±0.71 g.day-1, p=0.026) were increased from basal levels only when resistance exercise was combined with WP ingestion and not the NEAA control (NEAA MPS 0.072±0.004%h-1, NEAA ASR 10.23±0.80 g.day-1).&nbsp; Thus, ingestion of WP in combination with resistance training augments acute MPS responses in resistance trained young men. Conclusions We have developed a translational model of muscle protein synthetic bioactivity using in vitro, ex vivo and in vivo methodologies. We have shown that we can impact MPS in vitro using ex vivo human serum to condition media, that MPS in vitro is differentially regulated by ex vivo serum containing bioactive WP compared to a non-bioactive NEAA control, and that this tranlates for resistance exercise combined with WP in humans when MyoFSR is measured using stable isotope technology. &nbsp;These experiments demonstrate that ex vivo/in vitro experiments translate to the in vivo model and these methods can be used to inform both exercise and nutrient human interventions.&nbsp

Efecto de la estructura, digestibilidad y absorción de la beta-conglicinina de soja en su inmunorreactividad y propiedades antioxidantes

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Física Aplicada. Fecha de lectura: 19-11-200

Effect of the enzymatic deglycosylation of soy beta-conglycinin allergen on its antigenicity

Peer reviewe