Dietary Phenolics Research Articles

Innovations in extractable compounds from date seeds: Farms to future

<abstract> <p>Since ancient times, date fruit has been used as a staple food because of its high nutritional value and caloric content. With the development of food science and the application of modern instrumentation, we now know that date seeds contain large amounts of dietary fiber, phenols, polyphenols, amino acids, fatty acids, and many vitamins and minerals. Due to the presence of these functional food ingredients, date seeds are used in various applications, including foods such as bread, hot beverages, cosmetics such as hair and skin products, and as feed for culturing aquatic animals. Date seeds have been used in clinical applications, making use of their antioxidant, anti-inflammatory, anti-cancer, anti-diabetic, and antimicrobial properties. There is now growing awareness of the value of date seeds, which were considered a waste product. In this review, we focused on explaining the major biochemical constituents of date seeds and developing these constituents for various applications. We also highlight the expected developments in date seed use for the future.</p> </abstract>

(Poly)phenol-related gut metabotypes and human health: an update.

Dietary (poly)phenols have received great interest due to their potential role in the prevention and management of non-communicable diseases. In recent years, a high inter-individual variability in the biological response to (poly)phenols has been demonstrated, which could be related to the high variability in (poly)phenol gut microbial metabolism existing within individuals. An interplay between (poly)phenols and the gut microbiota exists, with (poly)phenols being metabolised by the gut microbiota and their metabolites modulating gut microbiota diversity and composition. A number of (poly)phenol metabolising phenotypes or metabotypes have been proposed, however, potential metabotypes for most (poly)phenols have not been investigated, and the relationship between metabotypes and human health remains ambiguous. This review presents updated knowledge on the reciprocal interaction between (poly)phenols and the gut microbiome, associated gut metabotypes, and subsequent impact on human health.

استخدام النواتج الثانوية لمخلفات التصنيع الغذائي في تحسين الصفات النوعية والقيمة الغذائية للمخبوزات

About 50% of the secondary plant waste generated during the industrial production of fruits and vegetables is wasted, which negatively affects the environment and costs a lot of money. The secondary plant waste is a rich source of nutrients that support human health and protect it from many diseases (obesity and heart disease). It is also a source of dietary fiber and phenols, which are antioxidants that can be separated from wheat bran, corn bran, rice, fruit and vegetable seeds. which were introduced in the manufacture of baked products. Many studies of baked products fortified with vegetable by-products showed an improvement in the quality characteristics in addition to an increase in their nutritional value. Therefore, the aim of this article was to highlight the importance of exploiting plant residues and using them in baked products as a sustainable way to increase their nutritional value and obtain cheap products.

Dietary fibre fractions rich in (poly)phenols from orange by-products and their metabolisation by in vitro digestion and colonic fermentation

Orange peel is an interesting by-product because of its composition, particularly its dietary fibre and flavanones. The aim of this work was to extract different fibre fractions from orange peel to obtain potential added-value ingredients and evaluate how the presence of fibre may interfere with (poly)phenol metabolism. Using an aqueous extraction, as a green extraction method, an insoluble fibre fraction (IFF) and a water-soluble extract (WSE) were obtained. Those fractions were analysed to determine the proximate and dietary fibre composition, hydration properties, (poly)phenol composition and antioxidant capacity, comparing the results with the orange peel (OP). The IFF presented the highest content of insoluble dietary fibre and the WSE showed the highest content of (poly)phenols, these being mainly flavanones. An in vitro faecal fermentation was carried out to evaluate the production of short-chain fatty acids (SCFAs) and lactate as prebiotic indicators; the IFF gave the highest production, derived from the greater presence of dietary fibre. Moreover, catabolites from (poly)phenol metabolism were also analysed, phenylpropanoic acids being the major ones, followed by phenylacetic acids and benzoic acids. These catabolites were found in higher quantities in WSE, because of the greater presence of (poly)phenols in its composition. IFF also showed a significant production of these catabolites, which was delayed by the greater presence of fibre. These results reveal that the new ingredients, obtained by an environmentally friendly water extraction procedure, could be used for the development of new foods with enhanced nutritional and healthy properties.

Long-Term Feeding of Dairy Goats with 40% Artichoke by-Product Silage Preserves Milk Yield, Nutritional Composition and Animal Health Status.

The aim of this work is to study the effect of 40% inclusion of artichoke by-product silage (AB) in dairy goat diets on milk yield, composition and animal health status during a full lactation period compared to an isoenergetic and isoproteic mixed ration based on alfalfa hay and a cereal and legume mixture. Milk yield was not affected by the dietary treatments, and neither was body weight. AB treatment reduced whey protein (0.38 vs. 0.42%, p < 0.05) and milk urea concentrations (687 vs. 773 mg/L, respectively, p < 0.001), and did not affect total true protein (3.22 vs. 3.24% p > 0.05) or other macro-composition variables. AB treatment showed higher milk concentrations of Ca (p < 0.05), Mn (p < 0.01), Cu (p < 0.01) and Zn (p < 0.001) compared to the control group (C). Slight differences were observed in milk fatty acid profile without any negative effects (p > 0.05) on the blood cholesterol and glucose of goats. The AB group reduced blood urea due to its high dietary total phenol content. However, it had a positive effect on β-hydroxybutyrate (p < 0.05) and nonesterified fatty acids (p > 0.05). It was concluded that 40% artichoke by-product inclusion in dairy goat feed for the whole lactation period (23 weeks) is a sustainable solution, reducing feeding cost by 12.5% per kg of dry matter, contributing to a better circular economy without any negative repercussions on the productivity and health of Murciano-Granadina dairy goats.

Therapeutic potential of plant-derived extracellular vesicles as nanocarriers for exogenous miRNAs

Cell-to-cell communication strategies include extracellular vesicles (EVs) in plants and animals. The bioactive molecules in a diet rich in vegetables and fruits are associated with disease-preventive effects. Plant-derived EVs (PDEVs) are biogenetically and morphologically comparable to mammalian EVs and transport bioactive molecules, including miRNAs. However, the biological functions of PDEVs are not fully understood, and standard isolation protocols are lacking. Here, PDEVs were isolated from four foods with a combination of ultracentrifugation and size exclusion chromatography, and evaluated as vehicles for enhanced transport of synthetic miRNAs. In addition, the role of food-derived EVs as carriers of dietary (poly)phenols and other secondary metabolites was investigated. EVs from broccoli, pomegranate, apple, and orange were efficiently isolated and characterized. In all four sources, 4 miRNA families were present in tissues and EVs. miRNAs present in broccoli and fruit-derived EVs showed a reduced RNase degradation and were ferried inside exposed cells.EVs transfected with a combination of ath-miR159a, ath-miR162a-3p, ath-miR166b-3p, and ath-miR396b-5p showed toxic effects to human cells, as did natural broccoli EVs alone. PDEVs transport trace amounts of phytochemicals, including flavonoids, anthocyanidins, phenolic acids, or glucosinolates. Thus, PDEVs can act as nanocarriers for functional miRNAs that could be used in RNA-based therapy.

Natural Phenolic Compounds with Neuroprotective Effects.

Neurodegenerative disorders are characterized by mitochondrial dysfunction and subsequently oxidative stress, inflammation, and apoptosis that contribute to neuronal cytotoxicity and degeneration. Huntington's (HD), Alzheimer's (AD), and Parkinson's (PD) diseases are three of the major neurodegenerative diseases. To date, researchers have found various natural phytochemicals that could potentially be used to treat neurodegenerative diseases. Particularly, the application of natural phenolic compounds has gained significant traction in recent years, driven by their various biological activities and therapeutic efficacy in human health. Polyphenols, by modulating different cellular functions, play an important role in neuroprotection and can neutralize the effects of oxidative stress, inflammation, and apoptosis in animal models. This review focuses on the current state of knowledge on phenolic compounds, including phenolic acids, flavonoids, stilbenes, and coumarins, as well as their beneficial effects on human health. We further provide an overview of the therapeutic potential and mechanisms of action of natural dietary phenolics in curing neurodegenerative diseases in animal models.

Dietary (Poly)phenols and Cognitive Decline: A Systematic Review and Meta-Analysis of Observational Studies.

This study aims to systematically review observational studies investigating the relation between dietary (poly)phenol consumption and various cognitive outcomes. Embase and PubMed databases are searched from inception to April 2023 for observational studies investigating the relation between dietary (poly)phenol intake and cognitive outcomes. For quantitative analyses, random effects models, subgroup analyses, and dose-response analyses are performed. A total of 37 studies are included in the systematic review. Among (poly)phenols, a higher intake of flavonoids is associated with better cognitive function and lower odds of cognitive decline (although with some exceptions). A quantitative meta-analysis shows an overall inverse association with cognitive impairment and reduced association with the incidence of dementia or related disorders for total flavonoids (relative risk (RR) = 0.83, 95% confidence interval (CI): 0.76, 0.89), anthocyanins (RR = 0.73, 95% CI: 0.60, 0.89), flavones (RR = 0.77, 95% CI: 0.63, 0.94), flavan-3-ols (RR = 0.86, 95% CI: 0.82, 0.91), and flavonols (RR = 0.88, 95% CI: 0.80, 0.96). Data on other (poly)phenolic compounds (i.e., phenolic acids) are promising but too preliminary. Habitual inclusion of flavonoids in the diet may play a preventive role against cognitive disorders.

Comparative study of dietary phenols with Tartary buckwheat protein (2S/13S): impact on structure, binding sites and functionality of protein.

This research was to investigate the interaction mechanism between 2S albumin and 13S globulin (2S and 13S, the most important storage proteins in Tartary buckwheat seeds) and three phenols (rutin, quercetin and myricetin) regarding the structural and antioxidant properties of their complexes. There are differences in the binding affinity of phenols for 2S and 13S. Rutin had a higher binding affinity for 2S, myricetin had a higher binding affinity for 13S, and 13S exhibited a higher affinity toward phenols than did 2S. Binding with phenols significantly changed the secondary and tertiary structures of 2S and 13S, decreased the surface hydrophobic value and enhanced the antioxidant capacity. Molecular docking and isothermal titration calorimetry showed that the binding processes were spontaneous and that there were hydrogen bonds, hydrophobic bonds and van der Waals force interactions between phenols and proteins. These findings could provide meaningful guidance for the further application of buckwheat protein complex. © 2023 Society of Chemical Industry.

A comprehensive review of pseudo-cereals: Nutritional profile, phytochemicals constituents and potential health promoting benefits

Pseudo-cereals with high nutritional value include amaranth, buckwheat, and quinoa. Pseudo-cereals have an excellent phytochemical profile as well as a nutritional profile rich in high-quality proteins. Dietary fibers, vitamins, minerals, phenolics, and other bio-active compounds are found in pseudo-cereals. Pseudo-cereals may be employed in a range of processed functional foods since they include bio-active polyphenols, flavonoids, fagopyritols, saponins, vitamins, and minerals. As a result, the commoditization of pseudo-cereals containing functional ingredients would assist those suffering from a range of lifestyle disorders. Pseudo-cereals are gluten-free foods that can be included in celiac disease diets since they contain barely any gluten. The inclusion of these in the diets of celiac patients could alleviate their deficiency of fiber intake. Their application in food items inculcates bakery products and pasta, which are mostly consumed. Based on this, this review evaluated the nutritional composition of pseudo-cereals, including protein, carbohydrate, dietary fiber, fat, minerals, and vitamins. Pseudocereals are reported to possess cardio-protective, anti-cancerous, hypocholesterolemic, anti-inflammatory, anti-obesity as well as antioxidant properties It has also been recommended that pseudocereals are an alternative source of complete protein that can be used to make peptides having potentaila to combact various chronic diseases. Several health benefits including allergies, celiac disease, hypocholesterolemia, anti-cancer, prebiotic action, and anti-diabetic effects have been highlighted. Potential industrial uses of pseudo-cereals include gluten-free baking items, noodles and pasta, the beverage sector, animal feed, granolas, and morning cereals are discussed.

Metabolomic insights into maternal and neonatal complications in pregnancies affected by type 1 diabetes

Aims/hypothesisType 1 diabetes in pregnancy is associated with suboptimal pregnancy outcomes, attributed to maternal hyperglycaemia and offspring hyperinsulinism (quantifiable by cord blood C-peptide). We assessed metabolomic patterns associated with risk factors (maternal hyperglycaemia, diet, BMI, weight gain) and perinatal complications (pre-eclampsia, large for gestational age [LGA], neonatal hypoglycaemia, hyperinsulinism) in the Continuous Glucose Monitoring in Women with Type 1 Diabetes in Pregnancy Trial (CONCEPTT).MethodsA total of 174 CONCEPTT participants gave ≥1 non-fasting serum sample for the biorepository at 12 gestational weeks (147 women), 24 weeks (167 women) and 34 weeks (160 women) with cord blood from 93 infants. Results from untargeted metabolite analysis (ultrahigh performance LC-MS) are presented as adjusted logistic/linear regression of maternal and cord blood metabolites, risk factors and perinatal complications using a modified Bonferroni limit of significance for dependent variables.ResultsMaternal continuous glucose monitoring time-above-range (but not BMI or excessive gestational weight gain) was associated with increased triacylglycerols in maternal blood and increased carnitines in cord blood. LGA, adiposity, neonatal hypoglycaemia and offspring hyperinsulinism showed distinct metabolite profiles. LGA was associated with increased carnitines, steroid hormones and lipid metabolites, predominantly in the third trimester. However, neonatal hypoglycaemia and offspring hyperinsulinism were both associated with metabolite changes from the first trimester, featuring triacylglycerols or dietary phenols. Pre-eclampsia was associated with increased abundance of phosphatidylethanolamines, a membrane phospholipid, at 24 weeks.Conclusions/interpretationAltered lipid metabolism is a key pathophysiological feature of type 1 diabetes pregnancy. New strategies for optimising maternal diet and insulin dosing from the first trimester are needed to improve pregnancy outcomes in type 1 diabetes.Graphical

Dietary phenolics and their microbial metabolites are poor inhibitors of trimethylamine oxidation to trimethylamine N-oxide by hepatic flavin monooxygenase 3

High circulating levels of trimethylamine N-oxide (TMAO) have been associated with cardiovascular disease risk. TMAO is formed through a microbiome-host pathway utilizing primarily dietary choline as a substrate. Specific gut microbiota transform choline into trimethylamine (TMA), and, when absorbed, host hepatic flavin-containing monooxygenase 3 (FMO3) oxidizes TMA into TMAO. Chlorogenic acid and its metabolites reduce microbial TMA production in vitro. However, little is known regarding the potential for chlorogenic acid and its bioavailable metabolites to inhibit the last step: hepatic conversion of TMA to TMAO. We developed a screening methodology to study FMO3-catalyzed production of TMAO from TMA. HepG2 cells were unable to oxidize TMA into TMAO due to their lack of FMO3 expression. Although Hepa-1 cells did express FMO3 when pretreated with TMA and NADPH, they lacked enzymatic activity to produce TMAO. Rat hepatic microsomes contained active FMO3. Optimal reaction conditions were: 50 µM TMA, 0.2 mM NADPH, and 33 µL microsomes/mL reaction. Methimazole (a known FMO3 competitive substrate) at 200 µM effectively reduced FMO3-catalyzed conversion of TMA to TMAO. However, bioavailable chlorogenic acid metabolites did not generally inhibit FMO3 at physiological (1 µM) nor supra-physiological (50 µM) doses. Thus, the effects of chlorogenic acid in regulating TMAO levels in vivo are unlikely to occur through direct FMO3 enzyme inhibition. Potential effects on FMO3 expression remain unknown. Intestinal inhibition of TMA production and/or absorption are thus likely their primary mechanisms of action.

Inversion of a paradigm: The positive roles of plant phenolics in dairy goat nutrition

The paradigm prevailing in the nineties, based on studies with goats fed tannin-rich browse as sole feed, was that dietary tannins are associated with impaired feed intake, increased fecal loss of N, and impaired NDF digestibility, hence, impaired productivity, with much research aiming at alleviating these negative effects. However, dairy goats fed plant phenolic-rich diets, and supplemented with concentrates will voluntarily ingest diets comprising more than 4% of tannins, without impairment of total feed intake and milk yield. Also, supplementing them with Poly (ethylene-glycol) MW 4000 is not needed. All plant phenolics, including condensed tannins, are partly digested, inferring that phenolic derivatives are absorbed and may reach tissues. In some studies, diets rich in plant phenolics are associated with the production of milk richer in protein and fat, reduced urea content, and improved curdling performance. Feeding goats with plant phenolics-rich diets is generally associated with inhibited bio-hydrogenation (BH) of fatty acids (FA) in the rumen, resulting in decreased saturated FA, increased polyunsaturated FA (PUFA) and, in particular C18:3–n3 but also a modified composition of de novo synthesized FA in goat milk that suggest direct action of phenolics on the mammary gland. Knowledge of the absorption of plant phenolics is still scarce for goats but even modest daily intakes seem to be associated with increased phenolic derivatives and anti-oxidative activity in plasma and milk. Dietary phenolic compounds may induce a local effect in the mammary gland and its production units (the mammary epithelium cells) encompassing increased cellular triglyceride and casein contents, and increased ATP production and non-mitochondrial oxygen consumption. Plant phenolics and their derivatives divert energy to production of milk fat, protein and lactose, with less energy directed to cellular damage control. Dietary plant phenolics are associated with improved goat health and production of healthier milk. In addition, dietary plant phenolics have anti-parasitic properties and are environment-friendly as they decrease gut methane emission and they increase fecal N at the expense of rapidly decomposable urinary N. Therefore, the attitude of scientists towards feeding plant phenolics has evoluted from mostly negative to mostly positive.

Unravelling phenolic metabotypes in the frame of the COMBAT study, a randomized, controlled trial with cranberry supplementation

Cranberry (poly)phenols may have potential health benefits. Circulating (poly)phenol metabolites can act as mediators of these effects, but they are subjected to an extensive inter-individual variability. This study aimed to quantify both plasma and urine (poly)phenol metabolites following a 12-week intake of a cranberry powder in healthy older adults, and to investigate inter-individual differences by considering the existence of urinary metabotypes related to dietary (poly)phenols. Up to 13 and 67 metabolites were quantified in plasma and urine respectively. Cranberry consumption led to changes in plasma metabolites, mainly hydroxycinnamates and hippuric acid. Individual variability in urinary metabolites was assessed using different data sets and a combination of statistical models. Three phenolic metabotypes were identified, colonic metabolism being the main driver for subject clustering. Metabotypes were characterized by quali-quantitative differences in the excretion of some metabolites such as phenyl-γ-valerolactones, hydroxycinnamic acids, and phenylpropanoic acids. Metabotypes were further confirmed when applying a model only focused on flavan-3-ol colonic metabolites. 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone derivatives were the most relevant metabolites for metabotyping. Metabotype allocation was well preserved after 12-week intervention. This metabotyping approach for cranberry metabolites represents an innovative step to handle the complexity of (poly)phenol metabolism in free-living conditions, deciphering the existence of metabotypes derived from the simultaneous consumption of different classes of (poly)phenols. These results will help contribute to studying the health effects of cranberries and other (poly)phenol-rich foods, mainly considering gut microbiota-driven individual differences.

Bioactive components and nutritional properties of fiber-rich cookies produced with different parts of oleaster (Elaeagnus angustifolia L.).

Oleaster (Elaeagnus angustifolia L.) possesses exocarp and endocarp layers enriched with abundant phytochemicals and fiber. Flours produced in different parts of oleaster were used in cookie formulation to improve the bioactive components and nutritional properties of cookies. The rheological properties of composite flours containing varying levels of oleaster exocarp flour (O'EX-F) and endocarp flour (O'EN-F), ranging from 0% to 30%, were assessed using Mixolab. The physical, chemical, nutritional, and sensory properties of cookies made with these flours were also analyzed. The substitution of O'EX-F and O'EN-F in the cookies enhanced redness and total color differences while decreasing hardness and improving the spread ratio. Furthermore, using these flours elevated the dietary fiber content of the cookies, particularly in terms of soluble and total dietary fiber. O'EX-F and O'EN-F also significantly increased free, bound, and total phenolic contents and antioxidant capacity. Sensory evaluation of cookies with 10% and 20% O'EX-F and O'EN-F indicated greater appreciation than control cookies. Incorporating 20% O'EX-F and 20% O'EN-F into cookies resulted in a notable increase in Ca, Mg, K, Fe, and Zn levels. The utilization of O'EX-F and O'EN-F, which contain a wealth of bioactive components, has significantly impacted the dough of rheology. Including these ingredients in cookie, formulations has demonstrated improvements in ash, dietary fiber content, phenolics, antioxidant activity, and overall technological quality while also providing distinctive sensory properties. This study has contributed a new composite flour to the existing literature and has facilitated the development of novel cookie products for the functional food industry. This article is protected by copyright. All rights reserved.

50-OR: First-Trimester Dietary Phenolic Compounds and Lipids Are Associated with Hyperinsulinism at Birth in Type 1 Diabetes Pregnancy

Objective: Type 1 diabetes in pregnancy is associated with perinatal complications attributed to offspring hyperinsulinism. Conventional management prioritises glycaemia in mid/late pregnancy to reduce hyperinsulinism, but the timing and pathophysiology of hyperinsulinism remains unclear. We assessed if hyperinsulinism, quantified by cord C-peptide at birth, was associated with early pregnancy metabolism. Methods and Outcomes: 111 women in the Continuous Glucose Monitoring (CGM) in Pregnant women with Type 1 diabetes Trial (CONCEPTT) had a livebirth with measurement of cord C-peptide. Liquid chromatography-mass spectrometry of maternal serum (12, 24, 34 wks; n=101) and cord blood (n=93) measured 2105 metabolites. Statistical analysis: linear regression of Cord C-peptide and metabolites with adjustment for maternal age, BMI, parity, ethnicity, education, intervention and glycemia (and birth gestation for offspring metabolites). Significance limit was p=0.001. Results: In maternal blood at 12 weeks, positive associations were noted between nine metabolites and cord C-peptide, including lipids (monoglycerides, triglycerides and phospholipids), saccharin and three other dietary phenolic compounds. At 24 weeks, two dietary phenols and several lipids maintained positive associations. At 34 weeks, 124 species in maternal blood showed positive associations with cord C-peptide, including saccharin, free fatty acids, monoglycerides, diglycerides, triglycerides, phospholipids. The profile was distinct from that of large-for-gestational age and neonatal hypoglycemia, despite the perceived pathophysiological overlap in these conditions. In cord blood, carnitines and betonicine were associated with C-peptide. Conclusions: Lipids, saccharin and other dietary phenols in early pregnancy warrant further investigation as potentially modifiable contributors to offspring hyperinsulinism in type 1 diabetes pregnancy. Disclosure C.L.Meek: Research Support; Dexcom, Inc. Z.A.Stewart: None. D.Feig: Advisory Panel; Novo Nordisk Canada Inc., Speaker's Bureau; Sanofi, Novo Nordisk Canada Inc. A.Koulman: None. H.R.Murphy: Advisory Panel; Medtronic, Research Support; Dexcom, Inc. Funding Diabetes UK; JDRF

Association of dietary flavan-3-ol intakes with plasma phenyl-γ-valerolactones: analysis from the TUDA cohort of healthy older adults

BackgroundDietary polyphenols, including flavan-3-ols (F3O), are associated with better health outcomes. The relationship of plasma phenyl-γ-valerolactones (PVLs), the products of colonic bacterial metabolism of F3O, with dietary intakes is unclear. ObjectivesTo investigate whether plasma PVLs are associated with self-reported intakes of total F3O and procyanidins+(epi)catechins. DesignWe measured 9 PVLs by uHPLC-MS-MS in plasma from adults (>60y) in the Trinity-Ulster-Department of Agriculture (TUDA study (2008 to 2012; n=5186) and a follow-up subset (2014 to 2018) with corresponding dietary data (n=557). Dietary (poly)phenols collected by FFQ were analyzed using Phenol-Explorer. ResultsMean (95% confidence interval [CI]) intakes were estimated as 2283 (2213, 2352) mg/d for total (poly)phenols, 674 (648, 701) for total F3O, and 152 (146, 158) for procyanidins+(epi)catechins. Two PVL metabolites were detected in plasma from the majority of participants, 5-(hydroxyphenyl)-γ-VL-sulfate (PVL1) and 5-(4ʹ-hydroxyphenyl)-γ-VL-3ʹ-glucuronide (PVL2). The 7 other PVLs were detectable only in 1-32% of samples. Self-reported intakes (mg/d) of F3O (r = 0.113, P = 0.017) and procyanidin+(epi)catechin (r = 0.122, P = 0.010) showed statistically significant correlations with the sum of PVL1 and PVL 2 (PVL1+2). With increasing intake quartiles (Q1-Q4), mean (95% CI) PVL1+2 increased; from 28.3 (20.8, 35.9) nmol/L in Q1 to 45.2 (37.2, 53.2) nmol/L in Q4; P = 0.025, for dietary F3O, and from 27.4 (19.1, 35.8) nmol/L in Q1 to 46.5 (38.2, 54.9) nmol/L in Q4; P = 0.020, for procyanidins+(epi)catechins. ConclusionsOf 9 PVL metabolites investigated, 2 were detected in most samples and were weakly associated with intakes of total F3O and procyanidins+(epi)catechins. Future controlled feeding studies are required to validate plasma PVLs as biomarkers of these dietary polyphenols.

Identification of nutritional biomarkers through highly sensitive and chemoselective metabolomics

The importance of a healthy diet for humans is known for decades. The elucidation of key molecules responsible for the beneficial and adverse dietary effects is slowly developing as the tools are missing. Carbonyl-containing metabolites are a common bioproducts through conversion of diet by the microbiome. In here, we have utilized our recently developed mass spectrometric methodology based on chemoselective conjugation of carbonyl-metabolites. The method has been applied for urine sample analysis from a dietary (poly)phenol intervention study (N = 78 individuals) for the first time. We have identified a series of carbonyl-metabolites of dietary origin and the chemical structure was validated for 30 metabolites. Our sensitive analysis led to the discovery of four unknown dietary markers with high sensitivity and selectivity (AUC > 0.91). Our chemical metabolomics method has been successfully applied for large-scale analysis and provides the basis for targeted metabolomics to identify unknown nutritional and disease-related biomarkers.

Excretion by subjects on a low (poly)phenol diet of phenolic gut microbiota catabolites sequestered in tissues or associated with catecholamines and surplus amino acids

Phenolic catabolites excreted by fasting subjects with a functioning colon and ileostomists on a low (poly)phenol diet have been investigated. Urine was collected over a 12 h fasting period after adherence to a low (poly)phenol diet for 36 h. UHPLC-HR-MS quantified 77 phenolics. Some were present in the urine of both groups in similar trace amounts and others were excreted in higher amounts by participants with a colon indicating the involvement of the microbiota. Most were present in sub- or low-µmol amounts, but hippuric acid dominated accounting on average for 60% of the total for both volunteer categories indicating significant production from sources other than non-nutrient dietary (poly)phenols. The potential origins of the phenolics associated with the low (poly)phenol diet, include endogenous catecholamines, surplus tyrosine and phenylalanine, and washout of catabolites derived from pre-study intakes of non-nutrient dietary (poly)phenols.

Accounting Gut Microbiota as the Mediator of Beneficial Effects of Dietary (Poly)phenols on Skeletal Muscle in Aging.

Sarcopenia, the age-related loss of muscle mass and function increasing the risk of disability and adverse outcomes in older people, is substantially influenced by dietary habits. Several studies from animal models of aging and muscle wasting indicate that the intake of specific polyphenol compounds can be associated with myoprotective effects, and improvements in muscle strength and performance. Such findings have also been confirmed in a smaller number of human studies. However, in the gut lumen, dietary polyphenols undergo extensive biotransformation by gut microbiota into a wide range of bioactive compounds, which substantially contribute to bioactivity on skeletal muscle. Thus, the beneficial effects of polyphenols may consistently vary across individuals, depending on the composition and metabolic functionality of gut bacterial communities. The understanding of such variability has recently been improved. For example, resveratrol and urolithin interaction with the microbiota can produce different biological effects according to the microbiota metabotype. In older individuals, the gut microbiota is frequently characterized by dysbiosis, overrepresentation of opportunistic pathogens, and increased inter-individual variability, which may contribute to increasing the variability of biological actions of phenolic compounds at the skeletal muscle level. These interactions should be taken into great consideration for designing effective nutritional strategies to counteract sarcopenia.