Dietary Intake of (Poly)phenols and Risk of All-Cause and Cause-Specific Mortality in the Mexican Teachers' Cohort Study.

BACKGROUND: Observational studies have reported that total (poly)phenol intake is associated with a reduction in all-cause and cardiovascular mortality, but mainly from high-income countries, where (poly)phenol intake may differ from that of low- and middle-income countries. OBJECTIVES: Our objective was to evaluate the association between the intake of total, all classes, and subclasses of (poly)phenols and risk of all-cause and cause-specific mortality in a Mexican cohort. METHODS: We used data from the Mexican Teachers' Cohort, which included 95,313 adult females. After a median follow-up of 11.2 y, 1725 deaths were reported, including 674 from cancer and 282 from cardiovascular diseases. (Poly)phenol intake was estimated using a validated food frequency questionnaire and the Phenol-Explorer database. Multivariable Cox models were applied to estimate the association between (poly)phenol intake and all-cause mortality and competitive risk models for cause-specific mortality. RESULTS: Comparing extreme quartiles, total (poly)phenol intake was associated with lower risk of all-cause [hazard ratio (HR)Q4vs.Q1: 0.88; 95% CI: 0.76, 0.99; P-trend = 0.01] and cancer mortality (HRQ4vs.Q1: 0.81; 95% CI: 0.64, 0.99; P-trend = 0.02). Among (poly)phenol classes, phenolic acids, particularly hydroxycinnamic acids from coffee, showed an inverse association with all-cause (HRQ4vs.Q1: 0.79; 95% CI: 0.69, 0.91; P-trend = 0.002) and cancer mortality (HRQ4vs.Q1: 0.75; 95% CI: 0.61, 0.94; P-trend = 0.03). No associations were observed with flavonoids or with cardiovascular mortality. CONCLUSION: Our study suggests that high (poly)phenol intake, primarily consisting of phenolic acids such as hydroxycinnamic acids, may have a protective effect on overall and cancer mortality. Null associations for flavonoid intake might be due to the potential underestimation of their intake in this population.

The impact of consuming technologically processed functional foods enriched/fortified with (poly)phenols on cardiometabolic risk factors: a systematic review of randomized controlled trials.

Cardiovascular diseases are a major global cause of death and healthcare costs, emphasizing the need for effective prevention and management of cardiometabolic risk factors. One promising approach is the consumption of technologically processed functional foods enriched/fortified with (poly)phenols. The current systematic review aimed to evaluate the human clinical trials evidence on the effect of intake of these foods on reducing the most common cardiometabolic risk factors. 12 randomized controlled studies were included in the systematic review, with varying food intake amounts (27-360 g/day) and (poly)phenol doses (32.5-850 mg/day). These interventions included consumption of functional bakery goods, cereal bars, pasta, chocolate, and yogurt, with supplementation periods spanning from 2 to 52 wk. Several foods, such as green tea extract-fortified rye bread and olive fruit (poly)phenol-fortified yogurt, significantly lowered blood pressure. Flavonoid-enriched chocolate, hydroxytyrosol-fortified bread, and other products influenced glucose metabolism. Additionally, various functional foods were associated with improved blood lipid levels. While these results indicate the health advantages of consuming technologically processed functional foods enriched/fortified with (poly)phenols, caution is warranted due to the scarcity and limitations of existing studies. Further research is needed to confirm and expand upon these results in the prevention and management of cardiometabolic risk factors.

Chemical Composition, Functional and Antioxidant Properties of Dietary Fibre Extracted from Lemon Peel after Enzymatic Treatment.

Lemon peel represents an interesting by-product owing to its content of dietary fibre (DF) and (poly)phenols, which is of great importance for its valorisation. Hence, the objective of this study was to characterise the DF, total phenolic content (TPC), and antioxidant capacity of two lemon-peel-derived ingredients using two different methods (drying with warm air and enzymatic hydrolysis with pectinesterase). The analysis included a DF assessment, followed by neutral sugars characterisation through GC-FID and uronic acids determination via colorimetry. Subsequently, TPC and antioxidant capacity using the FRAP method were quantified through spectrophotometry. The swelling capacity (SWC), water retention capacity (WRC), and fat absorption capacity (FAC) were also determined as functional properties. It was observed that pectinesterase treatment led to a reduction in soluble DF and an increase in insoluble DF. This treatment also affected the pectin structure, thereby diminishing its ability to absorb water and fat within its matrix. The TPC was also reduced, resulting in a decrease in antioxidant capacity. Conversely, employing warm air exhibited a noteworthy increase in antioxidant capacity. This underscores its crucial contribution to the valorisation of lemon peel, not only by diminishing the environmental impact but also by enabling the acquisition of fibre ingredients with a noteworthy antioxidant capacity.

Flavonoids and phenolic acids from sugarcane: Distribution in the plant, changes during processing, and potential benefits to industry and health.

Sugarcane (Saccharum sp.) plants are grown in warmer climates throughout the world and processed to produce sugar as well as other useful byproducts such as molasses and bagasse. Sugarcane is rich in (poly)phenols, but there has been no attempt to critically evaluate the published information based on the use of suitable methodologies. The objective of this review is to evaluate the quantitative and qualitative (poly)phenolic profiles of individual parts of the sugarcane plant and its multiple industrial products, which will help develop new processes and uses for sugarcane (poly)phenols. The quantitative analysis involves the examination of extraction, concentration, and analytical techniques used in each study for each plant part and product. The qualitative analysis indicates the identification of various (poly)phenols throughout the sugarcane processing chain, using only compounds elucidated through robust analytical methodologies such as mass spectrometry or nuclear magnetic resonance. In conclusion, sugarcane (poly)phenols are predominantly flavonoids and phenolic acids. The main flavonoids, derivatives of apigenin, luteolin, and tricin, with a substantial proportion of C-glycosides, are consistently found across all phases of sugarcane processing. The principal phenolic acids reported throughout the process include chlorogenic acids, as well as ferulic and caffeic acids mostly observed after hydrolysis. The derivation of precise quantitative information across publications is impeded by inconsistencies in analytical methodologies. The presence of multiple (poly)phenols with potential benefits for industrial applications and for health suggests sugarcane could be a useful provider of valuable compounds for future use in research and industrial processes.

Citrus polyphenols and risk of type 2 diabetes: Evidence from mechanistic studies.

Citrus fruits are a rich source of (poly)phenols, a group of dietary bioactive compounds that protect against developing type 2 diabetes. Our review critically evaluates how experimental in vitro and animal models have elucidated some of the underlying mechanisms on how citrus (poly)phenols affect the markers of type 2 diabetes. According to animal studies, the beneficial effects derived from consuming citrus compounds appear to be related to long-term effects, rather than acute. There are some notable effects from citrus (poly)phenol metabolites on post-absorptive processes, such as modulation of hepatic glucose metabolism and insulin sensitivity in target tissues, but with a more modest effect on digestion and sugar absorption within the gut. Experimental studies on cells and other systems in vitro have indicated some of the possible mechanisms involved, but ∼70% of the studies utilized unrealistically high concentrations and forms of the compounds, compromising physiological relevance. Future studies should discuss the relevance of concentration used in in vitro experiments, relative to the proposed site of action, and also examine the role of catabolites produced by the gut microbiota. Finally, it is important to examine the relationship between the gut microbiota and bioavailability on the action of citrus (poly)phenols.

Association between alcoholic (poly)phenol-rich beverage consumption and cognitive status in older adults living in a Mediterranean area.

The prevalence of cognitive disorders is growing and evidence suggests the putative role of plant-based foods and beverages containing (poly)phenols. The aim of this study was to explore the association between the consumption of (poly)phenol-rich beverages, including wine and beer, resveratrol intake, and cognitive status in a cohort of older adults. The dietary intakes were assessed using a validated food frequency questionnaire, and cognitive status using the Short Portable Mental Status Questionnaire. Multivariate logistic regression analyses showed that individuals in the second and third tertile of red wine consumption were less likely to have cognitive impairment than those in the first tertile. In contrast, only individuals in the highest tertile of white wine intake were having lower odds of cognitive impairment. No significant results were found for beer intake. Individuals with higher resveratrol intake were less likely to have cognitive impairment. In conclusion, consumption of (poly)phenol-rich beverages may potentially affect cognition among older adults.

Effect of In Vitro Gastrointestinal Digestion and Colonic Fermentation on the Stability of Polyphenols in Pistachio (Pistacia Vera L.).

The aim of this study was to evaluate the impact of in vitro gastrointestinal digestion and colonic fermentation on the polyphenol compounds from different varieties of pistachio by UHPLC-HRMS analysis. The total polyphenol content decreased significantly, mostly during oral (recoveries of 27 to 50%) and gastric digestion (recoveries of 10 to 18%), with no significant changes after the intestinal phase. After in vitro digestion, the hydroxybenzoic acids and the flavan-3-ols were the main compounds found in pistachio, with respective total polyphenol contents of 73 to 78% and 6 to 11%. More specifically, the main compounds determined after in vitro digestion were 3,4,5-trihydroxybenzoic acid, vanillic hexoside and epigallocatechin gallate. The colonic fermentation affected the total phenolic content of the six varieties studied, with a recovery range of 11 to 25% after 24 h of fecal incubation. A total of twelve catabolites were identified after fecal fermentation, the main compounds being the 3-(3'-hydroxyphenyl)propanoic, 3-(4'-hydroxyphenyl)propanoic, 3-(3',4'-dihydroxyphenyl)propanoic, 3-hydroxyphenylacetic acids and 3,4-dihydroxyphenyl-É£-valerolactone. Based on these data, a catabolic pathway for colonic microbial degradation of phenolic compounds is proposed. The catabolites identified at the end of the process are potentially responsible for the health properties attributed to pistachio consumption.

Exploring the Antioxidant Potential of Phenolic Compounds from Winery By-Products by Hydroethanolic Extraction.

The residues generated in the wine industry (pomace, stems, seeds, wine lees, and grapevine shoots) are a potential source of bioactive compounds that can be used in other industries despite being sometimes underestimated. Different extraction methods using various solvents and extraction conditions are currently being investigated. Due to its natural occurrence in wines, safe behavior, and low toxicity when compared to other organic solvents, ethanol is used as an extracting agent. The aim of this study was to identify the winery by-product from the Região Demarcada do Douro and its corresponding extraction solvents that yields the most favorable results in (poly)phenols content and antioxidant capacity. To achieve this, five different ratios of ethanol: water, namely 0:100, 25:75, 50:50, 75:25, and 100:0 (v/v), for extracting the phenolic compounds were employed. Afterwards, the determination of total phenolic content (TPC), ortho-diphenols content (ODC), and flavonoid content (FC) as well as the antioxidant capacity of the obtained extracts using three different methods was performed. Since the best results of the spectrophotometric assays were obtained mostly with hydroethanolic extracts of stems (50:50, v/v), identification by HPLC-DAD has carried out. It was possible to conclude that the Tinta Roriz variety displayed the highest number of identified (poly)phenols.

Prebiotic effects of plant-derived (poly)phenols on host metabolism: Is there a role for short-chain fatty acids?

The gut microbiota has been extensively investigated during the last decade because of its effects on host neuroendocrine pathways and other processes. The imbalance between beneficial and pathogenic bacteria, known as dysbiosis, may be a determining predisposing factor for many noncommunicable chronic diseases, such as obesity, type 2 diabetes mellitus, metabolic syndrome, and Alzheimer's disease. On the other hand, interventions aiming to reestablish the balance between microbiota components have been suggested as potential preventive therapeutic strategies against these disorders. Among these interventions, dietary supplementation with (poly)phenols has been highlighted due to the modulatory effects exerted by those compounds on the gut microbiota. In addition, (poly)phenol consumption is associated with increased production of short-chain fatty acids (SCFAs), a set of microbial metabolites whose actions are ascribed to improving the abovementioned metabolic disorders. Thus, this review discusses the modulation of the gut microbiota by prebiotic (poly)phenols based on in vivo studies performed with isolated (poly)phenolic compounds, their interaction with the gut microbiota and the production of SCFAs in pursuit of the molecular mechanisms underlying the health effects of (poly)phenols on host metabolism.

Flavonoids from edible fruits as therapeutic agents in neuroinflammation - a comprehensive review and update.

Neuroinflammation is a key process in the pathogenesis of many neurological disorders, i.e. Alzheimer's disease and Parkinson's disease. However, there are no anti-inflammatory medical interventions recommended so far in the treatment of neuroinflammation-related brain disorders. Therefore, the burden of searching for effective and safe antineuroinflammatory agents is well founded, especially in the aging society. Compounds of plant origin, mainly (poly)phenols, have attracted considerable attention in recent years. Notably, the role of flavonoids in ameliorating neuroinflammation is in the limelight. Thus, we used comprehensive literature retrieval to summarize the effects and active components of edible fruits and their phenolic compounds. As a result, this review presents a valuable summary of results of in vitro, ex vivo, and in vivo studies on the antineuroinflammatory effects of edible fruits and their (poly)phenolic extracts as well as dietary flavonoids and other selected (poly)phenols based on the detailed description of foregoing studies. Additionally, problems resulting from the limited bioavailability of (poly)phenols were discussed.

Changes in (poly)phenols intake and metabolic syndrome risk over ten years from adolescence to adulthood.

BACKGROUND AND AIMS: (Poly)phenols might contribute to prevent cardiovascular disease, but limited prospective studies exist among adolescents. This study aimed to evaluate within-subject longitudinal changes in (poly)phenols intakes and food group contributors while also exploring the association with metabolic syndrome risk (MetS) during 10 years of follow up in European adolescents becoming young adults. METHODS AND RESULTS: In 164 participants (58% girls, 13-18 y at baseline) from Ghent, Zaragoza and Lille, longitudinal data (2006-2016) on (poly)phenol intake was retrieved via 2 or 3 24 h recalls. Linear and logistic longitudinal regression tested the association of (poly)phenols intake (total and classes) with Mets risk or its components (waist-height-ratio, HDL cholesterol, LDL cholesterol, triglycerides, blood pressure and insulin resistance index), adjusted for age, sex, country and other nutrient intakes. The total (poly)phenols intake was 421 ± 107 mg/day (192 mg/1000 kcal/day) at baseline, while 610 ± 101 mg/day (311 mg/1000 kcal/day) at follow-up. The three major food sources for (poly)phenols were 'chocolate', 'fruit and vegetable juices', 'cakes and biscuits' during adolescence and 'coffee', 'tea' and 'chocolate' during adulthood. Phenolic acid intake was associated with less LDL increase over time, while stilbene intake with a steeper increase in triglycerides over time. CONCLUSIONS: Differences in major (poly)phenols contributors over time were partially explained by age-specific dietary changes like increased coffee and tea during adulthood. Some significant (poly)phenols-MetS associations might argue for nutrition-based disease prevention during adolescence, especially since adolescents had low (poly)phenols intake.

(Poly)phenol characterisation in white and red cardoon stalks: could the sous-vide technique improve their bioaccessibility?

This study aims to evaluate whether sous-vide cooking better preserves the (poly)phenol content and profile of red and white cardoon stalks versus traditional boiling, both before and after simulated oral-gastro-intestinal digestion. Thirty one (poly)phenols were quantified in red and white cardoon by HPLC-MS/MS, phenolic acids being >95%, and 5-caffeoylquinic and 1,5-dicaffeoylquinic acids the major ones. Although both varieties showed a similar profile, raw red cardoon had 1.7-fold higher (poly)phenol content than raw white cardoon. Culinary treatments decreased (poly)phenol content, but sous-vide cooked cardoon had a greater content than the boiled one, suggesting a protective effect. After gastrointestinal digestion, (poly)phenol bioaccessibility of boiled and sous-vide cooked cardoon (52.6-90.5%) was higher than that of raw samples (0.2-0.7%), although sous-vide system no longer played a protective effect compared to boiling. In summary, red cardoon was a richer source of bioaccessible (poly)phenols than white cardoon, even sous-vide cooked or boiled.

Dietary-Fibre-Rich Fractions Isolated from Broccoli Stalks as a Potential Functional Ingredient with Phenolic Compounds and Glucosinolates.

The Brassica oleracea industry generates large amounts of by-products to which value could be added because of the characteristics of their composition. The aim was to extract different fibre fractions from broccoli stalks to obtain potential new added-value ingredients. Using an ethanol and water extraction procedure, two fibre-rich fractions (total fibre fraction, TFB, and insoluble fibre fraction, IFB) were obtained. These fractions were analysed to determine the nutritional, (poly)phenols and glucosinolates composition and physicochemical properties, comparing the results with those of freeze-dried broccoli stalks (DBS). Although TFB showed a higher content of total dietary fibre, IFB had the same content of insoluble dietary fibre as TFB (54%), better hydration properties, higher content of glucosinolates (100 mg/100 g d.w.) and (poly)phenols (74.7 mg/100 g d.w.). The prebiotic effect was evaluated in IFB and compared with DBS by in vitro fermentation with human faecal slurries. After 48 h, the short-chain fatty acid (SCFA) production was higher with IFB than with DBS because of the greater presence of both uronic acids, the main component of pectin, and (poly)phenols. These results reveal that novel fibre-rich ingredients-with antioxidant, technological and physiological effects-could be obtained from broccoli stalks by using green extraction methods.

Bioactive compounds in lettuce: Highlighting the benefits to human health and impacts of preharvest and postharvest practices.

Lettuce is one of the most commonly consumed leafy vegetables worldwide and is available throughout the entire year. Lettuce is also a significant source of natural phytochemicals. These compounds, including glycosylated flavonoids, phenolic acids, carotenoids, the vitamin B groups, ascorbic acid, tocopherols, and sesquiterpene lactones, are essential nutritional bioactive compounds. This review aims to provide a comprehensive understanding of the composition of health-promoting compounds in different types of lettuce, the potential health benefits of lettuce in reducing the risks of chronic diseases, and the effect of preharvest and postharvest practices on the biosynthesis and accumulation of health-promoting compounds in lettuce.

A Comprehensive Review on the Interaction of Milk Protein Concentrates with Plant-Based Polyphenolics.

Functional properties and biological activities of plant-derived polyphenolic compounds have gained great interest due to their epidemiologically proven health benefits and diverse industrial applications in the food and pharmaceutical industry. Moreover, the food processing conditions and certain chemical reactions such as pigmentation, acylation, hydroxylation, and glycosylation can also cause alteration in the stability, antioxidant activity, and structural characteristics of the polyphenolic compounds. Since the (poly)phenols are highly reactive, to overcome these problems, the formulation of a complex of polyphenolic compounds with natural biopolymers is an effective approach. Besides, to increase the bioavailability and bioaccessibility of polyphenolic compounds, milk proteins such as whey protein concentrate, sodium caseinate, and milk protein concentrate act as natural vehicles, due to their specific structural and functional properties with high nutritional value. Therefore, milk proteins are suitable for the delivery of polyphenols to parts of the gastrointestinal tract. Therefore, this review reports on types of (poly)phenols, methods for the analysis of binding interactions between (poly)phenols-milk proteins, and structural changes that occur during the interaction.

(Poly)phenols in Inflammatory Bowel Disease and Irritable Bowel Syndrome: A Review.

(Poly)phenols (PPs) may have a therapeutic benefit in gastrointestinal (GI) disorders, such as irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD). The aim of this review is to summarise the evidence-base in this regard. Observational evidence does not give a clear indication that PP intake has a preventative role for IBD or IBS, while interventional studies suggest these compounds may confer symptomatic and health-related quality of life improvements in known patients. There are inconsistent results for effects on markers of inflammation, but there are promising reports of endoscopic improvement. Work on the effects of PPs on intestinal permeability and oxidative stress is limited and therefore conclusions cannot be formed. Future work on the use of PPs in IBD and IBS will strengthen the understanding of clinical and mechanistic effects.

Dietary fibre modifies gut microbiota: what's the role of (poly)phenols?

The association between dietary consumption of fibre and health-related gut bacteria is essential but not unique. (Poly)phenols are among the most important bioactive components contained in fibre-rich foods. For this reason, the role of (poly)phenols when considering dietary fibres and health outcomes should be taken into account, as synergic or mediating factors contributing to human health.

(Poly)phenolic Content and Profile and Antioxidant Capacity of Whole-Grain Cookies are Better Estimated by Simulated Digestion than Chemical Extraction.

It is widely recognized that the biological effects of phytochemicals cannot be attributed to the native compounds present in foods but rather to their metabolites endogenously released after intake. Bioavailability depends on bioaccessibility, which is the amount of the food constituent that is released from the matrix in the gastrointestinal tract. The use of chemical extraction to evaluate the content and profile of phytochemicals does not mirror the physiological situation in vivo, and their bioaccessibility should be considered while assessing their nutritional significance in human health. The current study was designed to compare the (poly)phenolic profile and content and antioxidant capacity of whole-grain (WG) cookies using chemical extraction and a more physiological approach based on simulated digestion. Three types of organic WG cookies (made with durum, Italian khorasan, or KAMUT® khorasan wheat) were considered, either fermented by Saccharomyces Cerevisiae or sourdough. Although the flour type and the fermentation process influenced the release of phytochemicals from the cookie matrix, in almost all samples, the simulated digestion appeared the most efficient procedure. Our results indicate that the use of chemical extraction for evaluation of the phytochemicals content and antioxidant capacity of food could lead to underestimation and underline the need for more physiological extraction methods.

Effects of Different Drying Methods on Untargeted Phenolic Metabolites, and Antioxidant Activity in Chinese Cabbage (Brassica rapa L. subsp. chinensis) and Nightshade (Solanum retroflexum Dun.).

Chinese cabbage (Brassica rapa L. subsp. chinensis) and Nightshade (Solanum retroflexum are popular traditional leafy vegetables consumed predominantly by rural Africans. Sun drying is adopted as a traditional method of postharvest preservation to store theses leaves during off seasons. The influence of different types of postharvest processing treatments, such as conventional oven drying, solar cabinet drying, sun drying and freeze drying, on the changes on colour properties and antioxidant components were investigated. Freeze-drying retained the ascorbic acid content, antioxidant activities, total chlorophyll content, green colour by reducing the colour difference (∆E). With regard to Chinese cabbage and Nightshade leaves, sun and microwave drying respectively had the most negative impact on all the identified phenolic compounds. The OPLS-DA and the UPLC-QTOF/MS and chemometric approach showed kaempferol-3-O-sophoroside, kaempferol-3-sophorotrioside-7-glucoside and hydroxyoctadecenedioic acid as the markers responsible for the separation of sun-dried samples from the other drying treatments in Chinese cabbage. Sinapoyl malate was not detected in sun-dried samples. Caffeoylmalic acid was identified as the marker compound to separate the other drying treatments from the microwave dried samples of Nightshade leaves. Trihydroxyoctadecadiene derivative and hydroxyoctadecanedioic acid were detected in microwaved samples. Due to the cost effectiveness, solar dryer cabinet treatment was recommended for drying both vegetables. The proximate analysis of solar dried functional powder of Chinese cabbage and Nightshade vegetables demonstrated higher contents of protein and dietary fibre.

Plasma urolithin metabolites correlate with improvements in endothelial function after red raspberry consumption: A double-blind randomized controlled trial.

Raspberries are a rich source of ellagitannins and anthocyanins. The aim of this work was to investigate whether raspberry consumption can improve vascular function and to understand which phenolic metabolites may be responsible for the effects. A 3 arm double-blind randomized controlled crossover human intervention trial was conducted in 10 healthy males. Flow-mediated dilation (FMD) was measured at baseline, 2 h, and 24 h post-consumption of 200 g and 400 g of red raspberries containing 201 or 403 mg of total (poly)phenols, or a matched control drink. Raspberry (poly)phenol metabolites were analyzed in plasma and urine by UPLC-QTOF mass spectrometry using authentic standards. Significant improvements in FMD were observed at 2 h (1.6% (95%CI 1.2, 1.9) and 1.2% (95% CI 0.8, 1.5)) and 24 h (1.0% (95% CI 0.6, 1.2) and 0.7% (95%CI 0.2, 0.9)) post-consumption of the 200 and 400 g raspberry drinks as compared to control, respectively. Plasma ellagic acid, urolithin A-3-glucuronide and urolithin A-sulfate correlated with the improvements in FMD at 2 and 24 h post consumption, respectively. Consumption of dietary achievable amounts of red raspberries acutely improves endothelial function up to 24 h and ellagitannins may be responsible for the observed effect.