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Plant-based proteins and polyphenols are increasingly being explored as functional food ingredients. Colloidal complexes were prepared from pea protein (PP) and grape seed proanthocyanidin (GSP) and the ability of the PP/GSP complexes to form and stabilize oil-in-water emulsions were investigated. The main interactions between PP and GSP were hydrogen bonding. The stability of PP-GSP complexes to environmental changes were studied: pH (2-9); ion strength (0-0.3 M); and temperature (30-90 °C). Emulsions produced using PP-GSP complexes as emulsifiers had small mean droplet diameters (~200 nm) and strongly negative surface potentials (~-60 mV). Compared to PP alone, PP-GSP complexes slightly decreased the isoelectric point, thermostability, and salt stability of the emulsions, but increased their storage stability. The presence of GSP gave the emulsions a strong salmon (red-yellow) color, which may be beneficial for some specific applications. These results may assist in the creation of more efficacious food-based strategies for delivering proanthocyanidins., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

After ingestion flavanols are metabolized by phase-II enzymes and the microbiota and are distributed throughout the body depending on several factors. Herein we aim to evaluate whether flavanols are tissue-accumulated after the long-term administration of a grape seed polyphenol extract (GSPE) in rats and to study if compounds present in tissues differ in a cafeteria-diet obesity state. For that, plasma, liver, mesenteric white adipose tissue (MWAT), brain, and aorta flavanol metabolites from standard chow-diet-fed (ST) and cafeteria-diet-fed (CAF) rats were analyzed by high-performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) 21 h after the last 12-week-daily GSPE (100 mg/kg) dosage. Results showed that long-term GSPE intake did not trigger a flavanol tissue accumulation, indicating a clearance of products at each daily dosage. Therefore, results suggest that polyphenol benefits in a disease state would be due to a daily pulsatile effect. Moreover, obesity induced by diet also influences the metabolism and bioavailability of flavanols in rats.

Sleep deprivation produces deficits in hippocampal synaptic plasticity and hippocampal-dependent memory storage. Recent evidence suggests that sleep deprivation disrupts memory consolidation through multiple mechanisms, including the down-regulation of the cAMP-response element-binding protein (CREB) and of mammalian target of rapamycin (mTOR) signaling. In this study, we tested the effects of a Bioactive Dietary Polyphenol Preparation (BDPP), comprised of grape seed polyphenol extract, Concord grape juice, and resveratrol, on the attenuation of sleep deprivation-induced cognitive impairment. We found that BDPP significantly improves sleep deprivation-induced contextual memory deficits, possibly through the activation of CREB and mTOR signaling pathways. We also identified brain-available polyphenol metabolites from BDPP, among which quercetin-3-O-glucuronide activates CREB signaling and malvidin-3-O-glucoside activates mTOR signaling. In combination, quercetin and malvidin-glucoside significantly attenuated sleep deprivation-induced cognitive impairment in -a mouse model of acute sleep deprivation. Our data suggests the feasibility of using select brain-targeting polyphenol compounds derived from BDPP as potential therapeutic agents in promoting resilience against sleep deprivation-induced cognitive dysfunction., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Objective: The mechanism action of the polyphenol-rich extracts from berries of Aronia melanocarpa (black chokeberry) and from grape seeds in the defence against homocysteine (Hcy) and its derivatives action in blood platelets is still unknown. In this study, the influence of the aronia extract and grape seeds extract (GSE) on the platelet adhesion to collagen and fibrinogen and the platelet aggregation during a model of hyperhomocysteinemia was investigated. The aim of our study in vitro was also to investigate superoxide anion radicals (O₂⁻•) production after incubation of platelets with Hcy, HTL and the aronia extract and GSE during a model of hyperhomocysteinemia (induced by reduced form of homocysteine at final dose of 100 μM) and the most reactive form of Hcy--its cyclic thioester, homocysteine thiolactone (HTL, 1 μM). Moreover, the additional aim of our study was also to establish and compare the influence of the aronia extract, GSE and resveratrol (3,4',5-trihydroxystilben), a phenolic compound, which has been supposed to be beneficial for the prevention of cardiovascular events, on selected steps of platelet activation., Methods: The effects of tested extracts on adhesion of blood platelets to collagen and fibrinogen were determined according to Tuszynski and Murphy. The platelet aggregation was determined by turbidimetry method using a Chrono-log Lumi-aggregometer., Results: We have observed that HTL, like its precursor-Hcy stimulated the generation of O₂⁻• (measured by the superoxide dismutase-inhibitable reduction of cytochrome c) in platelets and caused an augmentation of the platelet adhesion and aggregation induced by the strong physiological agonist-thrombin. Our present results in vitro also demonstrated that the aronia extract and grape seeds extract reduced the toxicity action of Hcy and HTL on blood platelet adhesion to collagen and fibrinogen, the platelet aggregation and superoxide anion radicals production in platelets, suggesting its potential protective effects on hemostasis during hyperhomocysteinemia., Conclusion: In the comparative studies, the aronia extract was found to be more effective antiplatelet factors, than GSE or resveratrol during a model of hyperhomocysteinemia. It gives hopes for development of diet supplements, which may be important during hyperhomocysteinemia.