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The role of non-energy-yielding nutrients on health has been meticulously studied, and the evidence shows that a compound can exert significant effects on health even if not strictly required by the organism. Phenolic compounds are among the most widely studied molecules that fit this description; they are found in plants as secondary metabolites and are not required by humans for growth or development, but they can influence a wide array of processes that modulate health across multiple organs and systems. The lower gastrointestinal tract is a prime site of action of phenolic compounds, namely, by their effects on gut microbiota and colonic health. As with humans, phenolic compounds are not required by most bacteria but can be substrates of others; in fact, some phenolic compounds exert antibacterial actions. A diet rich in phenolic compounds can lead to qualitative and quantitative effects on gut microbiota, thereby inducing indirect health effects in mammals through the action of these microorganisms. Moreover, phenolic compounds may be fermented by the gut microbiota, thereby modulating the compounds bioactivity. In the colon, phenolic compounds promote anti-inflammatory, anti-oxidant and antiproliferative actions. The aim of the present review is to highlight the role of phenolic compounds on maintaining or restoring a healthy microbiota and overall colonic health. Mechanisms of action that substantiate the reported evidence will also be discussed.

Avocado is an excellent source of phytochemicals with remarkable bioactive properties. This study evaluated the effect of ripeness stage of ‘Hass’ avocado on the profile and content of lipophilic and hydrophilic phytochemicals and their in vitro cytotoxic activity. Qualitative and quantitative analyses of the major phytochemicals were conducted in four stages of ripeness, using gas and liquid chromatography analyses. In general, phenolics, carotenoids, tocopherols, and phytosterols tended to increase during ripening. A decrease of individual phytochemicals was observed, namely, protocatechuic acid (0.36 to 0.03 mg 100 g−1 dw) and β-carotene (0.9 to 0.4 mg 100 g−1 dw), while quercetin and δ-tocopherol were only detected in a single ripeness stage (1 and 3, respectively). The major phytochemicals quantified at the end of ripening were epicatechin (12.66 mg 100 g−1 dw), lutein (0.5 mg 100 g−1 dw), α-tocopherol (12.4 mg 100 g−1 oil) and β-sitosterol (35.6 mg 100 g−1 dw) for phenolics, carotenoids, tocopherols and phytosterols, respectively. The cytotoxic activity of methanolic extracts of avocado was tested against RAW 264.7 and HeLa cells, where all RS showed a dose-dependent effect. We conclude that ripeness stage influences the concentration of specific compounds in each group of phytochemicals, as well as its in vitro cytotoxic activity, something that must be considered in future studies on the potential health benefits of avocado.

Substantial evidence from nutritional epidemiology links polyphenol-rich diets with reduced incidence of chronic disorders; however, biological mechanisms underlying polyphenol-disease relations remain enigmatic. Emerging evidence is beginning to unmask the contribution of the gastrointestinal tract on whole-body energy homeostasis, suggesting that the intestine may be a prime target for intervention and a fundamental site for the metabolic actions of polyphenols. During their transit through the gastrointestinal tract, polyphenols may activate enteric nutrient sensors ensuing appropriate responses from other peripheral organs to regulate metabolic homeostasis. Furthermore, polyphenols can modulate the absorption of glucose, attenuating exaggerated hormonal responses and metabolic imbalances. Polyphenols that escape absorption are metabolized by the gut microbiota and the resulting catabolites may act locally, activating nuclear receptors that control enteric functions such as intestinal permeability. Finally, polyphenols modulate gut microbial ecology, which can have profound effects on cardiometabolic health.

Cholesterol uptake and chylomicron synthesis are promoted by increasing glucose concentrations in both healthy and diabetic individuals during the postprandial phase. The goal of this study was to test whether acute inhibition of glucose uptake could impact cholesterol absorption in differentiated human intestinal Caco-2 cells. As expected, high glucose upregulated intestinal cholesterol metabolism promoting its uptake and incorporation in lipoproteins. This was accompanied by an increase in the gene expression of Niemann-Pick C1 Like 1 and proprotein convertase subtillisin/kexin type 9. Cholesterol uptake was attenuated by acute inhibition of glucose absorption by cytochalasin B, by a chamomile extract and by one of its main constituent polyphenols, apigenin 7-O-glucoside; however, chylomicron secretion was only reduced by the chamomile extract. These data support a potential indirect role for bioactives in modulating intestinal lipid pathways through effects on intestinal glucose uptake. This working hypothesis warrants further testing in an in vivo setting such as in hypercholesterolaemic or prediabetic individuals.

The role of non-energy-yielding nutrients on health has been meticulously studied, and the evidence shows that a compound can exert significant effects on health even if not strictly required by the organism. Phenolic compounds are among the most widely studied molecules that fit this description; they are found in plants as secondary metabolites and are not required by humans for growth or development, but they can influence a wide array of processes that modulate health across multiple organs and systems. The lower gastrointestinal tract is a prime site of action of phenolic compounds, namely, by their effects on gut microbiota and colonic health. As with humans, phenolic compounds are not required by most bacteria but can be substrates of others; in fact, some phenolic compounds exert antibacterial actions. A diet rich in phenolic compounds can lead to qualitative and quantitative effects on gut microbiota, thereby inducing indirect health effects in mammals through the action of these microorganisms. Moreover, phenolic compounds may be fermented by the gut microbiota, thereby modulating the compounds bioactivity. In the colon, phenolic compounds promote anti-inflammatory, anti-oxidant and antiproliferative actions. The aim of the present review is to highlight the role of phenolic compounds on maintaining or restoring a healthy microbiota and overall colonic health. Mechanisms of action that substantiate the reported evidence will also be discussed.

IntroductionBile acid (BA) biotransformation by gut bacteria impacts BA profile and signaling to nuclear receptors, such as the farnesoid X receptor (FXR) regulating glucose metabolism. Altered BA-FXR signaling was therefore investigated as a potential mechanism linking polyphenol-induced gut bacterial changes and improved glucose metabolism.Research design and methodsDiabetic db/db were fed low-fat diet (LFD) or LFD supplemented with a proanthocyanidin-rich extract of grape polyphenols (LFD-GP) for 4 weeks. Metabolic phenotypes, serum BAs, gut microbiota composition, and gene expression markers relevant to gut barrier and glucose metabolism were assessed. Gut organoids were used to investigate effects of individual BAs on ileal FXR activity.ResultsCompared with LFD-fed controls, GP supplemented db/db mice showed improved glucose metabolism, decreased relative abundance of gut bacteria associated with production of secondary BAs (SBAs), and depleted serum levels of SBAs taurohyodeoxycholic acid (THDCA), ω-muricholic acid (ωMCA), and tauro-ω-muricholic acid (TωMCA). Serum levels of primary BAs (PBAs) increased, consistent with higher gene expression of PBA synthesis enzyme Cyp7a1. GP-induced BA changes associated with FXR inhibition as evidenced by reduced expression of FXR-responsive genes Shp, Fgf15, and Fabp6 in ileum tissue as well as hepatic Shp, which negatively regulates PBA synthesis. GP treatment did not affect expression of hepatic Fxr or expression of Abcb11, Slc51b, and Obp2a genes controlling BA transport. Ceramide biosynthesis genes Smpd3, Sptlc2, and Cers4 were decreased in liver and intestine suggesting lower tissue ceramides levels may contribute to improved glucose metabolism. THDCA, ωMCA, and TωMCA behaved as FXR agonists in ileal organoid experiments; therefore, their depletion in serum of GP-supplemented db/db and wild type (WT) mice was consistent with FXR inhibition.ConclusionThese data suggest that by altering the gut microbiota, GPs modify BA-FXR signaling pathways to promote glucoregulation.

IntroductionIncidence rates of diabetes have been increasing and mortality rates have been decreasing. Our aim is the quantification of the effects of these on the prevalence and prediction of the future burden of diabetes.Research design and methodsFrom population-based registers of Denmark, we derived diabetes incidence and mortality rates and mortality rates for persons without diabetes for the period 1996–2016. Rates were modeled by smooth parametric terms using Poisson regression. Estimated rates were used to assess the relative contribution of incidence and mortality to changes in prevalence over the study period as well as for prediction of future rates and prevalence 2017–2040.ResultsThe major contributors to prevalence was increasing incidence (22%) and epidemiological imbalance between incidence and mortality (27%). The decrease in mortality rates over the period 1996–2016 contributes only 9% of the prevalent cases at 2016. We estimated that 467 000 persons in Denmark would be living with diabetes in 2030. The age distribution of patients in the period 2017–2030 is predicted to change toward older ages. The total number of persons needing diabetes care will increase by 67% over the next 13 years, an average annual increase of 4.0%.ConclusionsLowering mortality among patients with diabetes even further is not likely to influence the prevalence substantially. Since the size and the increase in incidence of diabetes are major drivers of the increasing prevalence, the prevention of new cases of diabetes is required.

Transient hyperglycaemia is a risk factor for type 2 diabetes and endothelial dysfunction, especially in subjects with impaired glucose tolerance. Nutritional interventions and strategies for controlling postprandial overshoot of blood sugars are considered key in preventing progress to the disease state. We have identified apigenin-7-O-glucoside, apigenin, and (Z) and (E)−2-hydroxy-4-methoxycinnamic acid glucosides as the active (poly)phenols in Chamomile (Matricaria recutita) able to modulate carbohydrate digestion and absorption in vitro as assessed by inhibition of α-amylase and maltase activities. The latter two compounds previously mistakenly identified as ferulic acid hexosides were purified and characterised and studied for their contribution to the overall bioactivity of chamomile. Molecular docking studies revealed that apigenin and cinnamic acids present totally different poses in the active site of human α-amylase. In differentiated Caco-2/TC7 cell monolayers, apigenin-7-O-glucoside and apigenin strongly inhibited D-[U-14C]-glucose and D-[U-14C]-sucrose transport, and less effectively D-[U-14C]-fructose transport. Inhibition of D-[U-14C]-glucose transport by apigenin was stronger under Na+-depleted conditions, suggesting interaction with the GLUT2 transporter. Competitive binding studies with molecular probes indicate apigenin interacts primarily at the exofacial-binding site of GLUT2. Taken together, the individual components of Chamomile are promising agents for regulating carbohydrate digestion and sugar absorption at the site of the gastrointestinal tract.

1 Scope: High glycaemic sugars result in blood‐glucose spikes, while large doses of post‐prandial fructose inundate the liver, causing an imbalance in energy metabolism, both leading to increased risk of metabolic malfunction and type 2 diabetes. Acarbose, used for diabetes management, reduces post‐prandial hyperglycaemia by delaying carbohydrate digestion. 2 Methods and results: Chamomile and green teas both inhibited digestive enzymes (α‐amylase and maltase) related to intestinal sugar release, as already established for acarbose. However, acarbose had no effect on uptake of sugars using both differentiated human Caco‐2 cell monolayers and Xenopus oocytes expressing human glucose transporter‐2 (GLUT2) and GLUT5. Both teas effectively inhibited transport of fructose and glucose through GLUT2 inhibition, while chamomile tea also inhibited GLUT5. Long term incubation of Caco‐2/TC7 cells with chamomile tea for 16 h or 4 days did not enhance the observed effects, indicating that inhibition is acute. Sucrase activity was directly inhibited by green tea and acarbose, but not chamomile. 3 Conclusion: These findings show that chamomile and green teas are potential tools to manage absorption and metabolism of sugars with efficacy against high sugar bolus stress inflicted, for example, by high fructose syrups, where the drug acarbose would be ineffective.

The effect of temperature (6, 15 and 30 °C) during ageing on the colour, phytochemical composition and bioactivity of roselle wine was investigated over 12 months. At the end of ageing, wines stored at 6 °C had the highest colour density and lowest polymeric anthocyanins. The initial concentration of most of the individual phenolic compounds decreased during ageing, with reduction of monomeric anthocyanins contributing to the formation of anthocyanin-derivatives (pyranoanthocyanins), eight of which were identified tentatively and reported here for the first time in roselle wine. The decrease in individual phenolic compounds did not affect inhibition of α-glucosidase (maltase) activity, which remained relatively low but stable throughout ageing. Diethyl succinate was the only volatile clearly influenced by ageing temperature, with the most pronounced effect at 30 °C (∼256 fold increase). In summary, the final concentrations of anthocyanins and diethyl succinate were the major compounds influenced by ageing temperature.

The consumption of fruits and vegetables has increased in the past few years, not only because of their attractive sensorial properties, but also for their nutritional and health benefits. Antioxidants are compounds found in fresh fruits and vegetables, and evidence of their role in the prevention of degenerative diseases is continuously emerging. However, the antioxidants in some fruits and vegetables can be lost during handling after harvest, even during minimal processing and storage. In this sense, postharvest treatments are needed to preserve the quality and antioxidant potential of fresh produce. Postharvest treatments and technologic strategies (including ultraviolet light, controlled and modified atmospheres, heat treatments, and application of natural compounds, such as edible coatings, active packaging, microencapsulation, and nanoemulsion) have shown positive and promising results to maintain fruit and vegetable antioxidant potential. The purpose of this review is to analyze and propose the application of postharvest strategies to maintain, or even improve, the antioxidant status of fruits and vegetables, thus offering options to maximize health benefits to consumers.

This work evaluated the effect of carnauba and mineral oil coatings on the bioactive compounds and antioxidant capacity of tomato fruits (cv. “Grandela”). Carnauba and mineral oil coatings were applied on fresh tomatoes at two maturity stages (breaker and pink) over 28 day of storage at 10 °C was evaluated. Bioactive compound and antioxidant activity assays included total phenols, total flavonoids, ascorbic acid (ASA), lycopene, DPPH radical scavenging activity (%RSA), trolox equivalent antioxidant capacity (TEAC) and oxygen radical absorbance capacity assay (ORAC). The total phenolic, flavonoid and lycopene contents were significantly lower for coated fruit than control fruits. However, ascorbic acid content was highest in fruits treated with carnauba, followed by mineral oil coating and control fruits. The ORAC values were highest in breaker tomatoes coated with carnauba wax, followed by mineral oil-coated fruits and controls. No significant differences in ORAC values were observed in pink tomatoes. % RSA and TEAC values were higher for controls than for coated fruit. Edible coatings preserve the overall quality of tomatoes during storage without affecting the nutritional quality of fruit. We found that the physiological response to the coatings is in function of the maturity stage of tomatoes. The information obtained in this study support to use of edible coating as a safe and good alternative to preserve tomato quality, and that the changes of bioactive compounds and antioxidant activity of tomato fruits, was not negatively affected. This approach can be used by producers to preserve tomato quality.

Exotic fruit consumption and processing is increasing worldwide due to the improvement in preservation techniques, transportation, marketing systems and consumer awareness of health benefits. The entire body of tropical exotic fruits is rich in bioactive compounds, such as phenolic constituents, carotenoids, vitamins and dietary fiber. However, the fruit processing industry deals with the large percentage of byproducts, such as peels, seeds and unused flesh, generated in the different steps of the processing chains. In most cases, the wasted byproducts can present similar or even higher contents of bioactive compounds than the final produce does. The aim of this review is to promote the production and processing of exotic fruits highlighting the possibility of the integral exploitation of byproducts rich in bioactive compounds. Amongst the possible uses for these compounds that can be found in the food industry are as antioxidants (avoiding browning and lipid oxidation and as functional food ingredients), antimicrobials, flavoring, colorants and texturizer additives. Finally, the importance of extraction techniques of bioactive compounds designated as food additives is also included.

Avocado (Persea americana) is an important tropical fruit and a good source of lipophilic phytochemicals such as monounsaturated fatty acids, carotenoids, vitamin E and sterols that have been inversely related to cardiovascular diseases. However, their antioxidant capacities have received far less attention compared with hydrophilic phytochemicals in this fruit. In this context, this study evaluated the effect of the stage of ripeness of ‘Hass’ avocado on the content of lipophilic and hydrophilic phytochemicals and their correlation with the antioxidant capacity. In every ripeness stage the fatty acids, total phenolic and flavonoid content as well as the antioxidant capacity were evaluated. Physiological and physico-chemical analysis were also performed including respiration rate, ethylene production, firmness, color (L*, °Hue, and Chroma), dry matter and oil content. In general, total phenols increased during ripening, while flavonoids slightly decreased. The main fatty acid identified was oleic acid (about 67–70% of total content). In general, a significant increase in monounsaturated and saturated fatty acids was observed during avocado ripening while polyunsaturated fatty acid content decreased (p

Tropical fruits production, trade and consumption have increased significantly due to their attractive sensory and nutrimental properties; nevertheless, their highly perishable nature limits their postharvest life. Postharvest treatments have been used to preserve quality of fresh produce and have been focused mainly on preserving freshness and avoid microbial growth. However, an improvement on the antioxidant system as a secondary response under certain adverse environmental and stress conditions has been observed, including some types of stress used as postharvest treatments. This review focuses on analyzing and proposing some possible mechanisms induced by postharvest treatments affecting the antioxidant status of treated tropical fruits.

Excessive post-prandial glucose concentration is associated with an increased risk of developing type 2 diabetes. Polyphenols represent a biologically active class of molecules which have been test...

Investigaciones recientes han demostrado que estos compuestos son capaces de prevenir y disminuir diferentes formas de enfermedades cardiovasculares y distintos tipos de cáncer, lo cual se debe, en parte, a su capacidad antioxidante. Además, las concentraciones de estos compuestos, así como su estatus antioxidante, están en función de la variedad y del estado de madurez en el que se encuentre el fruto, sin embargo, hasta el momento, estos atributos solo han sido reportados para frutos en estado de madurez comercial. En este contexto, el objetivo del presente estudio fue evaluar el efecto de la maduración de aguacate ‘Hass’ sobre su fisiología y propiedades físico-químicas, contenido de compuestos antioxidantes (lipofílicos e hidrofílicos) así como la capacidad antioxidante total. En general, los fenoles totales se incrementaron durante la maduración, mientras que el contenido de flavonoides se redujo ligeramente. El principal ácido graso identificado fue el ácido oleico (alrededor de 67-70% del contenido total). Además, se observó un incremento significativo en el contenido de ácidos grasos monoinsaturados y saturados durante la maduración del fruto, mientras que el contenido de ácidos grasos poli-insaturados disminuyó (p

Pecan (Carya illinoinensis) is a tree nut native to North America with high oil content. Pecan oil is rich in unsaturated fatty acids and other lipid soluble phytochemicals. Many geographical and environmental factors are responsible for the phytochemical content of the oil, and little current information exists on the properties of pecans grown in northern México. We formulated the hypothesis that pecans grown in multiple locations are exposed to different environmental conditions which alter the concentration of the phytochemicals in the oil. We characterized oil from pecans harvested in 2009 and 2010, in three different regions in northern Mexico. The content of individual fatty acids varied significantly within growing location (mainly oleic and linoleic, which were inversely related) and from year to year (mainly linolenic). Phytosterols and tocopherols also showed significant variation among locations; polyphenols were statistically similar in all samples. Oxidative stability of pecan oil, evaluated by differential scanning calorimetry, was similar to other oils with a similar content of unsaturated fatty acids. It may be concluded that the chemical composition of pecan oil is sensitive to the environment in which it is produced, but on average, the studied pecan oils were good sources of phytochemicals.

Problem statement: Tomato (Lycopersicon esculentum Mill.) is one of the most widely consumed fresh vegetables in the world; however, its highly perishable nature limits its postharvest life. Major losses in tomato quality and quantity occur between harvest and consumption. Therefore, the application of new technologies to extend the postharvest life of this commodity is needed. The use of edible coatings appears to be a good alternative. Approach: We evaluated the effect of carnauba and mineral oil coatings on the postharvest quality of tomato fruits (cv. “Grandela”). Stafresh 2505™ (carnauba) and Stafresh 151™ (mineral oil) coatings were applied on fresh tomatoes at two maturity stages (breaker and pink). The quality of tomatoes was evaluated periodically at 0, 5, 10, 15, 21 and 28 days of storage at 10°C, plus 2 days at 20°C. For respiration rate analysis, tomatoes were kept at 20°C for 16 days. Results: At the beginning of the study, CO2 production was reduced by 38 and 46% when applying the mineral oil coating on breaker and pink tomatoes, respectively. In addition, early during the study, the mineral oil coating showed suppression of ethylene biosynthesis at both maturity stages. Both coatings reduced 30% PG activity of tomato tissue. At the end of storage, mineral oil coatings delayed color changes and reduced weight losses for up 70 and 46% at the breaker and pink stages, respectively. Conclusion/Recommendations: Respiration rate, color, weight loss and enzyme activity were positively affected by mineral oil coating at both maturity stages. No effects on firmness, titratable acidity and pH were found by the coating application. We concluded that mineral oil coating could be a good alternative to preserve the quality and extend the postharvest life of tomato fruit.