Explore the vast range of titles available.

Dietary flavanols are food constituents found in certain fruits and vegetables that have been linked to cognitive aging. Previous studies suggested that consumption of dietary flavanols might specifically be associated with the hippocampal-dependent memory component of cognitive aging and that memory benefits of a flavanol intervention might depend on habitual diet quality. Here, we tested these hypotheses in the context of a large-scale study of 3,562 older adults, who were randomly assigned to a 3-y intervention of cocoa extract (500 mg of cocoa flavanols per day) or a placebo [(COcoa Supplement and Multivitamin Outcomes Study) COSMOS-Web, NCT04582617]. Using the alternative Healthy Eating Index in all participants and a urine-based biomarker of flavanol intake in a subset of participants [n = 1,361], we show that habitual flavanol consumption and diet quality at baseline are positively and selectively correlated with hippocampal-dependent memory. While the prespecified primary end point testing for an intervention-related improvement in memory in all participants after 1 y was not statistically significant, the flavanol intervention restored memory among participants in lower tertiles of habitual diet quality or habitual flavanol consumption. Increases in the flavanol biomarker over the course of the trial were associated with improving memory. Collectively, our results allow dietary flavanols to be considered in the context of a depletion–repletion paradigm and suggest that low flavanol consumption can act as a driver of the hippocampal-dependent component of cognitive aging.

Polyphenols are a group of phytochemicals with potential health-promoting effects. They are classified as flavonoid (flavonols, flavanols, flavones, flavanones, isoflavones, and anthocyanins) and non-flavonoid molecules (phenolic acids, hydroxycinnamic acids, lignans, stilbenes, and tannins). Although an increasing number of trials have shown a correlation among polyphenol consumption and a reduction in risk factors for chronic diseases, discrepancies in explaining their positive effects have been found in terms of the bioavailability. In fact, polyphenols show a low bioavailability due to several factors: interaction with the food matrix, the metabolic processes mediated by the liver (phase I and II metabolism), intestine and microbiota. On the other hand, the biological activities of phenol compounds may be mediated by their metabolites, which are produced in vivo, and recent studies have confirmed that these molecules may have antioxidant and anti-phlogistic properties. This review discusses the studies performed in vivo, which consider the polyphenol bioavailability and their different food sources. Factors influencing the biological effects of the main classes of polyphenols are also considered.

Wine is one of the most consumed beverages around the world. It is composed of alcohols, sugars, acids, minerals, proteins and other compounds, such as organic acids and volatile and phenolic compounds (also called polyphenols). Polyphenols have been shown to be highly related to both (i) wine quality (color, flavor, and taste) and (ii) health-promoting properties (antioxidant and cardioprotective among others). Polyphenols can be grouped into two big families: (i) Flavonoids, including anthocyanidins, flavonols, flavanols, hydrolysable and condensed tannins, flavanones, flavones and chalcones; and (ii) Non-flavonoids, including hydroxycinnamic acids, hydroxybenzoic acids, stilbenes, tyrosol and hydroxytyrosol. Each group affects in some way the different properties of wine to a greater or a lesser extent. For that reason, the phenolic composition can be managed to obtain singular wines with specific, desirable characteristics. The current review presents a summary of the ways in which the phenolic composition of wine can be modulated, including (a) invariable factors such as variety, field management or climatic conditions; (b) pre-fermentative strategies such as maceration, thermovinification and pulsed electric field; (c) fermentative strategies such as the use of different yeasts and bacteria; and (d) post-fermentative strategies such as maceration, fining agents and aging. Finally, the different extraction methods and analytical techniques used for polyphenol detection and quantification have been also reviewed.

Abiotic stresses, such as salt and heat stress, coexist in some regions of the world and can have a significant impact on agricultural plant biomass and production. Rice is a valuable crop that is susceptible to salt and high temperatures. Here, we studied the role of flavanol 3-hydroxylase in response to combined salt and heat stress with the aim of better understanding the defensive mechanism of rice. We found that, compared with wild-type plants, the growth and development of transgenic plants were improved due to higher biosynthesis of kaempferol and quercetin. Furthermore, we observed that oxidative stress was decreased in transgenic plants compared with that in wild-type plants due to the reactive oxygen species scavenging activity of kaempferol and quercetin as well as the modulation of glutathione peroxidase and lipid peroxidase activity. The expression of high-affinity potassium transporter ( HKT ) and salt overly sensitive ( SOS ) genes was significantly increased in transgenic plants compared with in control plants after 12 and 24 h, whereas sodium-hydrogen exchanger ( NHX ) gene expression was significantly reduced in transgenic plants compared with in control plants. The expression of heat stress transcription factors (HSFs) and heat shock proteins (HSPs) in the transgenic line increased significantly after 6 and 12 h, although our understanding of the mechanisms by which the F3H gene regulates HKT , SOS , NHX , HSF , and HSP genes is limited. In addition, transgenic plants showed higher levels of abscisic acid (ABA) and lower levels of salicylic acid (SA) than were found in control plants. However, antagonistic cross talk was identified between these hormones when the duration of stress increased; SA accumulation increased, whereas ABA levels decreased. Although transgenic lines showed significantly increased Na+ ion accumulation, K+ ion accumulation was similar in transgenic and control plants, suggesting that increased flavonoid accumulation is crucial for balancing Na+/K+ ions. Overall, this study suggests that flavonoid accumulation increases the tolerance of rice plants to combined salt and heat stress by regulating physiological, biochemical, and molecular mechanisms.

Flavanols are natural occurring polyphenols abundant in fruits and vegetables to which have been attributed to beneficial effects on health, and also against metabolic diseases, such as diabetes, obesity and metabolic syndrome. These positive properties have been associated to the modulation of different molecular pathways, and importantly, to the regulation of immunological reactions (pro-inflammatory cytokines, chemokines, adhesion molecules, nuclear factor-κB [NF-κB], inducible enzymes), and the activity of cells of the immune system. In addition, flavanols can modulate the composition and function of gut microbiome in a prebiotic-like manner, resulting in the positive regulation of metabolic pathways and immune responses, and reduction of low-grade chronic inflammation. Moreover, the biotransformation of flavanols by gut bacteria increases their bioavailability generating a number of metabolites with potential to affect human metabolism, including during metabolic diseases. However, the exact mechanisms by which flavanols act on the microbiota and immune system to influence health and disease remain unclear, especially in humans where these connections have been scarcely explored. This review seeks to summarize recent advances on the complex interaction of flavanols with gut microbiota, immunity and inflammation focus on metabolic diseases.

Flavonoids are polyphenolic compounds subdivided into 6 groups: isoflavonoids, flavanones, flavanols, flavonols, flavones and anthocyanidins found in a variety of plants. Fruits, vegetables, plant-derived beverages such as green tea, wine and cocoa-based products are the main dietary sources of flavonoids. Flavonoids have been shown to possess a wide variety of anticancer effects: they modulate reactive oxygen species (ROS)-scavenging enzyme activities, participate in arresting the cell cycle, induce apoptosis, autophagy, and suppress cancer cell proliferation and invasiveness. Flavonoids have dual action regarding ROS homeostasis—they act as antioxidants under normal conditions and are potent pro-oxidants in cancer cells triggering the apoptotic pathways and downregulating pro-inflammatory signaling pathways. This article reviews the biochemical properties and bioavailability of flavonoids, their anticancer activity and its mechanisms of action.

Cocoa and its products are rich sources of polyphenols such as flavanols. These compounds exert antioxidant and anti-inflammatory activities, accountable for cocoa health-promoting effects. However, cocoa polyphenols are poorly absorbed in the intestine, and most of them cannot reach the systemic circulation in their natural forms. Instead, their secondary bioactive metabolites are bioavailable, enter the circulation, reach the target organs, and exhibit their activities. In fact, once reaching the intestine, cocoa polyphenols interact bidirectionally with the gut microbiota. These compounds can modulate the composition of the gut microbiota exerting prebiotic mechanisms. They enhance the growth of beneficial gut bacteria, such as Lactobacillus and Bifidobacterium, while reducing the number of pathogenic ones, such as Clostridium perfringens. On the other hand, bioactive cocoa metabolites can enhance gut health, displaying anti-inflammatory activities, positively affecting immunity, and reducing the risk of various diseases. This review aims to summarize the available knowledge of the bidirectional interaction between cocoa polyphenols and gut microbiota with their various health outcomes.

Background Vegetable amaranth is a source of natural phytopigments and functional components of the commercial food industry for sustainable health benefits across the globe. It is guessed that recently identified amaranth (drought-tolerant) genotypes may contain ample phytopigments and phytochemicals suitable to extract juice as drinks. Hence, phytopigments and phytochemicals content of amaranth were assessed in detail for suitability as drinks to feed the phytochemicals deficient community across the globe. Results The selected amaranth contained adequate carbohydrates, protein, moisture, and dietary fiber, phytopigments, minerals, phytochemicals including the ability to scavenge radicals. Nine flavonoids compounds were estimated in amaranth genotypes including six flavonols, one flavanol, one flavone, and one flavanone. It is the first effort in which we identified one flavonol such as myricetin, one flavanol, such as catechin, one flavone i. e., apigenin, and one flavanone, like naringenin in drought-tolerant vegetable amaranth. Across six flavonols, quercetin and rutin were the most noteworthy compounds followed by myricetin and isoquercetin. Across the accessions, AT7 and AT15 had abundant phytochemicals, and radical quenching ability including considerable proximate, nutraceuticals, and phytopigments in comparison to the accessions AT3 and AT11. AT15 demonstrated the maximum total flavonols including the highest rutin and hyperoside. AT7 showed high total flavonols including the highest quercetin, isoquercetin, myricetin, and kaempferol. The association of values revealed that studied phytopigments and phytochemicals of vegetable amaranth accessions demonstrated good radical quenching ability of 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and 2,2- Diphenyl-1-picrylhydrazyl equivalent to Trolox. Conclusions These advance lines AT7 and AT15 had abundant nutraceuticals, phytopigments, and phytochemicals including radical quenching ability. These lines might significantly contribute to the promotion of health benefits and feeding the community across the globe deficit in nutraceuticals and antioxidants. Identified flavonoid compounds open the new route for pharmacological study.

In this pre-registered study, we investigated the effects of acute cocoa flavanol (CF) consumption on cognitive control and response inhibition processes, at two different dosage levels. This crossover study was randomized, placebo-controlled, gender-balanced, and double-blind, and included 36 healthy adult participants. Participants consumed three different drinks across separate sessions: a placebo drink containing alkalized cocoa powder, a low-dose drink with 415 mg CF, and a medium-dose drink with 623 mg CF, both derived from flavanol-rich cocoa powder. Following each treatment, participants completed the Flanker, Simon, and Go/No-go tasks in a counterbalanced order. We analyzed accuracy and response times for congruent and incongruent trials in the Simon and Flanker tasks, and commission errors, omission errors, and response times in the Go/No-go task. The acute effects of CF on cognitive control and response inhibition were examined using (Generalized) Linear Mixed Model analysis, which included random intercepts, fixed effects, and random slopes. Results revealed that neither dose of CF acutely improved accuracy, interference scores, errors, or response times in these three tasks. Furthermore, neither participant gender nor BMI predicted performance in cognitive control or response inhibition beyond the effects of the treatment conditions. Taken together, these findings suggest that acute cocoa flavanol consumption has no significant effect on cognitive control or response inhibition in healthy young adults.

Flavonoids are natural polyphenol secondary metabolites that are widely produced in planta. Flavonoids are ubiquities in human dietary intake and exhibit a myriad of health benefits. Flavonoids-induced biological activities are strongly influenced by their in situ availability in the human GI tract, as well as the levels of which are modulated by interaction with the gut bacteria. As such, assessing flavonoids–microbiome interactions is considered a key to understand their physiological activities. Here, we review the interaction between the various classes of dietary flavonoids (flavonols, flavones, flavanones, isoflavones, flavan-3-ols and anthocyanins) and gut microbiota. We aim to provide a holistic overview of the nature and identity of flavonoids on diet and highlight how flavonoids chemical structure, metabolism and impact on humans and their microbiomes are interconnected. Emphasis is placed on how flavonoids and their biotransformation products affect gut microbiota population, influence gut homoeostasis and induce measurable physiological changes and biological benefits.