Effect of red wines with different in vitro antioxidant activity on oxidative stress of high-fat diet rats

Trans-resveratrol reduced hepatic oxidative stress in an animal model without inducing an upregulation of nuclear factor erythroid 2-related factor 2

Trans-resveratrol, a widely used supplement for humans, aims to enhance the body's antioxidant defense. Studies suggest that it exerts anti-inflammatory and antioxidant effects by activating the nuclear factor erythroid 2-related factor 2 (Nrf2). In order to evaluate this hypothesis, LDLr(-/-) mice were fed a Western diet to induce liver inflammation and oxidative stress. One group was fed a diet containing 0.60 mg/day of trans-resveratrol (RESV), while another group received no dietary supplementation (CONT). Oxidative stress biomarkers and inflammatory cytokines were assessed in liver homogenates. It was observed that trans-resveratrol decreased hepatic oxidative stress by increasing the GSH/GSSG ratio and reducing malondialdehyde (MDA) concentration. However, the RESV group exhibited a reduction in Nrf2 relative expression compared to CONT. Additionally, trans-resveratrol supplementation reduced nuclear factor-κB (NF-κB) expression but led to an increase in IL-6, with no significant changes observed in tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) concentrations. Overall, these findings indicate that the in vivo antioxidant impact induced by trans-resveratrol supplementation in hepatic tissue did not correlate with increase of inflammatory cytokines and Nrf2 relative expression. Further exploration of alternative mechanisms, such as direct radical scavenger activity, is warranted to elucidate the antioxidant effect.

Ameliorative effects of aqueous extract from rosemary on oxidative stress and inflammation pathways caused by a high-fat diet in C57BL/6 mice

Rosemary is an herb exhibits biological properties, attenuates inflammation, oxidative stress, and improves lipid profile. Here, we evaluated the effects of rosemary aqueous extract (RE) on mice fed with a high-fat diet (HFD). Male C57BL/6 mice were administered a control diet or HFD for 10 weeks. The treated groups received RE in the diet at different concentrations: 25, 250, and 500 mg/100 g. After 10 weeks, serum concentrations of glucose, lipid, insulin, leptin, adiponectin, and cytokines were evaluated and the oxygen radical absorbance capacity was determined. Histological analysis was performed to determine the concentrations of triacylglycerides (TG), total cholesterol, cytokines, and antioxidant enzymes as well as the expression of genes involved in lipid metabolism, oxidative stress, and inflammation. The dietary RE ameliorated HFD-induced weight gain, adipose tissue weight, glucose intolerance, and insulin, leptin, and free fatty acid levels. Reduction in hepatic TG deposition was observed. The levels of inflammatory cytokines decreased, and the expression of genes involved in lipid metabolism increased. RE mitigated oxidative stress and reduced the production of reactive oxygen species in HepG2 and 3T3-L1 cells. Therefore, RE is a potential therapeutic agent for the prevention of inflammation and oxidative stress outcomes associated with obesity.

Zebrafish Model Insights into Mediterranean Diet Liquids: Olive Oil and Wine

In this review, we explored the potential of a zebrafish model to investigate the antioxidant effects of key components of the Mediterranean diet, namely, olive oil and wine, in the context of preventing age-related diseases, particularly cardiovascular conditions. This paper explores the spectrum of observational studies to preclinical investigations and ultimately converges toward potential translational insights derived from animal experimentation. This review highlights the potential and underutilization of zebrafish as an experimental model in this domain. We highlighted the genetic proximity of zebrafish to humans, offering a unique opportunity for translational insights into the health benefits of olive oil and wine. Indeed, we wanted to focus on the potential of zebrafish to elucidate the health benefits of olive oil and wine while calling for continued exploration to unlock its full potential to advance our knowledge of age-related disease prevention within the Mediterranean diet framework.

Protective Effects of Wine Polyphenols on Oxidative Stress and Hepatotoxicity Induced by Acrylamide in Rats

In recent years, it has been increasingly suggested that the consumption of natural polyphenols, in moderate amounts, is beneficial for health. The aim of this study was to investigate the efficacy of a red wine (the administered dose of 7 mL/kg/day being equivalent to ~16.5 mg/kg/day total polyphenols) compared to a white wine (the administered dose of 7 mL/kg/day being equivalent to ~1.7 mg/kg/day total polyphenols), on the prevention of acrylamide-induced subacute hepatic injury and oxidative stress in Wistar rats. Hepatic damage due to acrylamide intoxication (the administered dose being 250 µg/kg body weight, for 28 days, by intragastric gavage) was assessed by employing biochemical parameters (aspartate aminotransferase (AST) and alanine aminotransferase (ALT)) and by histopathological studies. Markers of oxidative damage were measured in terms of plasma malondialdehyde (MDA), hepatic Thiobarbituric Acid Reactive Substances (TBARS) and glutathione (GSH) levels, and liver antioxidant enzyme (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)) activities. Regarding hepatic enzyme activities, treatment with red wine significantly decreased the AST values (p < 0.05), while for the ALT values only a normalization tendency was observed. Treatment with red wine and white wine, respectively, significantly prevented the increase in MDA and TBARS levels (p < 0.05), as well as the depletion of GSH (p < 0.05). Red wine treatment normalized the activities of the antioxidant enzymes CAT and SOD in rats intoxicated with acrylamide, while supplementing the diet with white wine did not produce significant differences in the antioxidant enzyme activities. Histopathological findings revealed a moderate protective effect of red wine after four weeks of daily consumption. Our findings provide evidence that red wine, having a higher phenolic content than white wine, has a significant protective effect on oxidative stress and liver injury induced by acrylamide in rats, through its antioxidative activity.

Organic Beet Leaves and Stalk Juice Attenuates the Glutathione Peroxidase Increase Induced by High-Fat Meal in Dyslipidemic Patients: A Pilot Double-Blind, Randomized, Controlled Trial

The beet, including the leaves and stalk (BLS), is a vegetable with great antioxidant potential. The aim of this study was to evaluate the differences in the nutritional composition and the concentration of total phenolics between the organic and conventional BLS and to verify whether the ingestion of an organic BLS juice containing different concentrations of polyphenols modulated some biomarkers of oxidative stress after the ingestion of a high-fat meal in individuals with dyslipidemia. A controlled, randomized, double-blind, crossover clinical trial with a washout period of 1 week was carried out. A 12-h fasting blood sample was collected. Afterward, the participants consumed a high-fat meal, followed by the ingestion of a placebo or one of the organic BLS juices containing either 32.0 or 77.5 mg/100 mL of polyphenols. Blood samples were obtained 30, 60, 120 and 180 min after the first blood collection. The composition analysis showed that organic BLS had a better nutritional composition than conventional ones. The high-fat meal induced postprandial hypertriglyceridemia after 120 min (p < 0.001) and increased the concentration of malondialdehyde after 30 min (p < 0.001). In addition, there was a significant increase in GPx in 30 min (p = 0.026). This increase was attenuated in the group that received the highest dose of polyphenols when compared with the placebo after 30 min (p = 0.045). Therefore, the organic BLS juice containing 77.5 mg of polyphenols was efficient at modulating one of the postprandial mechanisms of enzymatic antioxidant protection in individuals with dyslipidemia.

Anti-Diabetic and Antioxidant Activities of Red Wine Concentrate Enriched with Polyphenol Compounds under Experimental Diabetes in Rats

We obtained red wine concentrate, which was enriched with natural polyphenolic compounds (PC concentrate). The main purpose was to study the hypoglycemic and antioxidant effects of the red wine concentrate, and its impact on key hematological parameters of rats with experimental diabetes mellitus. While administrating the red wine concentrate to rats with diabetes, partial recovering of glucose tolerance was promoted, as well as normalization of glycated hemoglobin level, an increase in the quantity of erythrocytes and hemoglobin concentration. PC concentrate had anti-radical effect, which was determined using 2,2-diphenyl-1-picrylhydrazylradical (DPPH) method and effectively inhibited oxidation of phosphatidylcholine liposomes, induced by 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) as a free radical generator. It was also confirmed that PC concentrate had antioxidant properties in vivo. The contents of lipid peroxidation and protein oxidation products, the activity of catalase, and glutathione peroxidase (GPx) were increased in the plasma of rats with diabetes mellitus. At the same time, the activity of superoxide dismutase (SOD) was decreased. The concentrate of red wine had a corrective effect on investigated indicators and caused their normalization in plasma of diabetic animals.

Twenty-five years of total antioxidant capacity measurement of foods and biological fluids: merits and limitations

This review summarises 25 years of investigations on antioxidants research in foods and biological fluids and critically analyses the merits and limitations of using the total antioxidant capacity (TAC) measurement in the metabolomic era. An enormous bulk of knowledge was produced regarding the antioxidant capacity of foods and large TAC databases were developed. A direct link between a food TAC value and any health benefit is erroneous and has led to several cases of consumer deception. However, the striking epidemiological evidence associating a high dietary TAC with some disease prevention and the availability of well-constructed TAC databases deserve attention and must be taken into account to establish the usefulness of measuring TAC in both foods and biological samples. The in vivo TAC measurement, usually performed in plasma, is influenced by many external factors, such as dietary habits, as well as environmental and behavioural factors, which are integrated towards homeostatic control by fine physiological mechanisms with high inter-individual variability. Therefore, plasma TAC cannot be considered as a unique biomarker of individual antioxidant status. However, the combined evaluation of plasma TAC with known markers of disease, individual metabolism, inflammation and genetics, as well as with markers of gut microbiota composition and activity, may lead to the identification of populations that are more responsive to food/diet TAC. In this framework, the appropriate use of TAC measurement both in food and in vivo can still provide support for the interpretation of complex phenomena and be a tool for sample screening when making a quick decision toward in-depth research investigations. © 2018 Society of Chemical Industry.

Noni (Morinda citrifolia L.) wine prevents the oxidative stress and obesity in mice induced by high-fat diet

Noni (Morinda citrifolia L.) is rich in polyphenols, flavonoids, terpenoids, and iridoids. However, its bad taste and smell make noni fruit unsuitable for consumption. After fermentation, noni wine becomes free from the undesirable smell. Nevertheless, it is still unclear whether processed noni could retain its original nutrients and effects. Therefore, we conducted a series of evaluations on the nutritional composition and efficacy of noni wine. Our results showed that the polyphenol, flavonoid, and vitamin C contents in noni wine were 558.80, 234.42, and 0.30 mg/L, respectively. Our animal experiments showed that 40 ml kg^-1  day^-1 noni wine could reduce bodyweight, as well as the levels of body fat, serum triglycerides, total cholesterol, and low-density lipoprotein, while it simultaneously increased the amount of energy expenditure and activity, and improved the systemic antioxidant capacity in mice following a high-fat diet. The results of the gene expression and western blot analyses showed that 40 ml kg^-1  day^-1 noni wine could regulate the Nrf2 pathway and improve the antioxidant enzyme gene expression in mice maintained on a high-fat diet, thereby improving body lipid metabolism, reducing fatty acid synthesis, and promoting fatty acid β-oxidation. Our study indicated that drinking 40 ml kg^-1  day^-1 noni wine could effectively prevent high-fat diet-induced oxidative stress and obesity in mice. PRACTICAL APPLICATIONS: Noni fruit is rich in nutrients but its bad smell and hardship of processing make its commercialization difficult. Previous studies mainly focused on fresh noni juice and its primary processed products, while few noni products, of poor taste and low quality, are available in the market. Therefore, the fruit wine with both the nutritive values and the special flavor of noni has broad market prospects. Our work provides a valuable reference for the commercialization of noni wine.

Green tea polyphenols and epigallocatechin-3-gallate protect against perfluorodecanoic acid induced liver damage and inflammation in mice by inhibiting NLRP3 inflammasome activation

Perfluorodecanoic acid (PFDA) is a highly toxic food contaminant that is extensively used in food applications as surface antifouling agent. In this present study, we aimed to assess whether green tea polyphenols (GTPs) and epigallocatechin-3-gallate (EGCG) exert protective effects against PFDA-induced liver damage and inflammation in mice. A mouse model to evaluate liver toxicity was established by giving mice drinking water containing different concentrations of PFDA. GTPs or EGCG (0.32%, w/v) were co-administered to mice exposed to PFDA in drinking water. Overall, GTPs and EGCG extended the survival time and inhibited weight loss among mice who received a lower dose of PFDA. Moreover, GTPs and EGCG ameliorated hepatic oxidative stress, cell apoptosis, necrosis, steatosis, edema, and degeneration, reduced hepatic inflammation and NLRP3 inflammasome activation caused by a moderate dose of PFDA. Taken together, these results show that GTPs or EGCG (or green tea intake) supplements can be beneficial for people exposed to PFDA.

The Role of Wine in Modulating Inflammatory Processes: A Review

Several epidemiological studies associated the consumption of wine with the reduction of the risk factors for cardiovascular disease and certain cancers, as well as for diabetes. These conditions are characterized by inflammatory mechanisms in addition to other biological mechanisms. Acute and chronic inflammation is mediated by a plethora of biomarkers production and pathway activation. Since the health promoting properties of wine in different pathological conditions may include the reduction of inflammation, the aim of this paper was to collect and review the in vitro, in vivo, and human studies performed to evaluate the effects of wine on different models of inflammation. Although great variability in wine intake, period of consumption, and content of phenolic compounds was observed, data from both human and animal studies showed a positive modulation of inflammatory biomarkers (cytokines, coagulation parameters) and oxidative stress (mainly malondialdehyde) involved in cardiovascular function. In addition, some convincing evidence was obtained in different models suggesting a positive modulation of risk factors for gastric and intestinal inflammation. Contradictory results were obtained for metabolic syndrome and type 2 diabetes. To date, no significant paper has been published in the area of immune function. Integrating in vivo data and in vitro studies, the NF-κB pathway has been identified as a critical target for the protective properties of a moderate wine consumption.

Comparison between red wine and isolated trans-resveratrol on the prevention and regression of atherosclerosis in LDLr (-/-) mice

Moderate consumption of red wine has been widely associated with reduced cardiovascular risk, mainly due to its composition in phenolic compounds with antioxidant activity, such as resveratrol. The objective of this study was to compare the effect of red wine vs. trans-resveratrol consumption on the prevention and regression of atherosclerosis in LDLr ^(-/-) mice. This study consisted of two protocols: "Prevention" (PREV) and "Regression" (REGR). Both protocols included four groups: red wine (WINE), dealcoholized red wine (EXT), trans-resveratrol (RESV), and control (CONT). In PREV protocol, animals received a regular diet for 8 weeks and then switched to an atherogenic diet for the following 8 weeks, while the opposite was performed in REGR. Animals that received atherogenic diet after an initial period of standard diet (PREV) gained more body weight (39.25±2.30%) than the opposite (29.27±1.91%, P=.0013), suggesting an interaction between age and weight gain. Trans-resveratrol showed the highest hypocholesterolemic effect during PREV, reducing total cholesterol, LDL-C, VLDL-C and HDL-C. Supplementation with trans-resveratrol and dealcoholized red wine changed the fatty acids profile in the liver in both protocols, leading to an increase of MDA concentrations and SOD activity in the PREV protocol. In conclusion, supplementation with trans-resveratrol, red wine and the same wine without alcohol altered biomarkers of oxidative stress and lipidemia but had no effect on the prevention or regression of fatty streaks. These data suggest that cardiovascular protection associated with the "French Paradox" may be a result of synergistic effects between wine and the Mediterranean diet.

In vitro antioxidant and antihypertensive compounds from camu-camu (Myrciaria dubia McVaugh, Myrtaceae) seed coat: A multivariate structure-activity study

Camu-camu (Myrciaria dubia) pulp, seeds, and skin are widely known because of their nutritional properties. However, the seed coat has never been studied as a source of bioactive compounds. Herein, we characterized the phenolic composition, the antioxidant activity, and inhibition of angiotensin-converting enzyme (ACE) of three different extracts (water, propanone, and ethanol) from this residue and assessed the structure-activity using bivariate and multivariate statistical approaches. Phenolic acids and flavonoids were quantified by high-performance liquid chromatography while the ferric reducing antioxidant power (FRAP), inhibition of lipid peroxidation using egg yolk and Wistar rat brain, scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH^•) radical, Folin-Ciocalteu reducing capacity (FCRC), and the inhibition of angiotensin-converting enzyme (ACE) by the extracts were also analyzed. t-Resveratrol was found in camu-camu seed coat for the first time. The aqueous extract had the highest total phenolic content, FRAP, DPPH^•, FCRC, and inhibition of lipid oxidation using both chemical and biological assays, while the propanone extract showed the opposite behavior but it presented higher in vitro antihypertensive activity. The ethanolic extract exhibited intermediate values for the responses. The association between chemical composition and the functional properties of the camu-camu seed coat extracts were revealed using correlation analysis and principal component analysis.

Beet Stalks and Leaves (Beta vulgaris L.) Protect Against High-Fat Diet-Induced Oxidative Damage in the Liver in Mice

Some flavonoids identified in beet stalks can help the antioxidant endogenous defenses during a chronic inflammation process. The current study investigates the effect of polyphenols present in beet stalks and leaves on liver oxidative damage in mice fed a high-fat diet (HF). The control (CT) or HF diet groups were supplemented with dehydrated beet stalks and leaves (SL) or beet stalk and leaf ethanolic extract (EX). In terms of Vitexin-rhaminoside equivalents (VRE), EX groups received ~5.91 mg of VRE·100 g⁻¹ diet, while the SL groups received ~3.07 mg VRE·100 g⁻¹ diet. After 8 weeks, we evaluated fasting blood glucose; cholesterol, hepatic Malondialdehyde (MDA) levels and hepatic Glutathione (GSH), Glutathione peroxidase (GPx), Glutathione reductase (GR) and Superoxide dismutase (SOD) activity. Dehydrated beet stalks and leaves (HFSL) attenuated the deleterious effects of a HF diet on lipid metabolism, reduced fasting blood glucose levels, ameliorated cholesterol levels and reduced GPx and GR activities (p < 0.05) compared to the HF group. However; the addition of ethanolic extract from beet stalks and leaves was unable (p > 0.05) to prevent the liver damage caused by HF diet in mice. The presence of flavonoids, such as Vitexin derivatives in beet stalks and leaves can help the liver damage induced by HF diet.

Antioxidant activity, total phenolics and flavonoids contents: Should we ban in vitro screening methods?

As many studies are exploring the association between ingestion of bioactive compounds and decreased risk of non-communicable diseases, the scientific community continues to show considerable interest in these compounds. In addition, as many non-nutrients with putative health benefits are reducing agents, hydrogen donors, singlet oxygen quenchers or metal chelators, measurement of antioxidant activity using in vitro assays has become very popular over recent decades. Measuring concentrations of total phenolics, flavonoids, and other compound (sub)classes using UV/Vis spectrophotometry offers a rapid chemical index, but chromatographic techniques are necessary to establish structure-activity. For bioactive purposes, in vivo models are required or, at the very least, methods that employ distinct mechanisms of action (i.e., single electron transfer, transition metal chelating ability, and hydrogen atom transfer). In this regard, better understanding and application of in vitro screening methods should help design of future research studies on 'bioactive compounds'.

Bioactive compounds as an alternative for drug co-therapy: Overcoming challenges in cardiovascular disease prevention

Different pharmacological interventions have been applied with success to reduce the progression of atherosclerosis. However, many patients are not good responders or must interrupt treatment due to adverse effects. Bioactive compounds such as omega-3 fatty acids (n-3 FA), plant sterol esters (PSE) and phenolic compounds (PHC) are natural molecules with great potential to reduce the atherosclerosis burden by reducing inflammation, LDL cholesterol (LDL-C) and oxidative stress, respectively. Although their physiological effects on biomarkers are much lower than those expected by drugs used for the same purpose, bioactive compounds can easily be incorporated into the daily diet and present no adverse effects. However, little is known about the combination of n-3 FA, PSE, PHC, and drugs in atherosclerosis progression. This review article summarizes potential effects of co-therapies involving n-3 FA, PSE, and PHC combined with major hypolipidemic drugs on atherosclerosis biomarkers and clinical outcomes. Evidence of additive and/or complementary effects regarding drugs action reveals possible roles for bioactive compounds in disease management. Pharmaceutical companies, physicians, and food scientists should be prepared to better understand this type of interaction and its consequences in terms of efficacy and life quality.

Oxidative stress induced by Se-deficient high-energy diet implicates neutrophil dysfunction via Nrf2 pathway suppression in swine

The mechanism of the interaction between Se deficiency and high energy remains limited. The aim of the current study was to identify whether Se-deficient, high-energy diet can induce oxidative stress, and downregulate the Nrf2 pathway and phagocytic dysfunction of neutrophils. We detected the phagocytic activity, ROS production, protein levels of Nrf2 and Nrf2 downstream target genes, and the mRNA levels of 25 selenoproteins, heat shock proteins, and cytokines in neutrophils. Cytokine ELISA kits were used to measure the serum cytokines. The concentration of ROS was elevated (P < 0.05) in obese swine fed on a low Se diet (less than 0.03 mg/kg Se) compared to control swine. The protein levels of Nrf2 and its downstream target genes were depressed during Se deficiency and high-energy intake. The mRNA levels of 16 selenoproteins were significantly decreased (P < 0.05) in the Se-deficient group and Se-deficient, high-energy group compared to the control group. However, the mRNA levels of 13 selenoproteins in peripheral blood neutrophils were upregulated in high energy group, except TrxR1, SelI and SepW. In summary, these data indicated that a Se-deficient, high-energy diet inhibits the Nrf2 pathway and its regulation of oxidative stress, and prompted a pleiotropic mechanism that suppresses phagocytosis.

Bioactivities and Health Benefits of Wild Fruits

Wild fruits are exotic or underutilized. Wild fruits contain many bioactive compounds, such as anthocyanins and flavonoids. Many studies have shown that wild fruits possess various bioactivities and health benefits, such as free radical scavenging, antioxidant, anti-inflammatory, antimicrobial, and anticancer activity. Therefore, wild fruits have the potential to be developed into functional foods or pharmaceuticals to prevent and treat several chronic diseases. In the present article, we review current knowledge about the bioactivities and health benefits of wild fruits, which is valuable for the exploitation and utilization of wild fruits.

Phenolic composition, physicochemical properties and antioxidant activity of interspecific hybrids of grapes growing in Poland

The study evaluated fruit quality parameters and chemical properties (soluble solids, pH, total acidity and total sugars content, phenolic compounds and antioxidant activity (ABTS, FRAP and ORAC methods)) of 30 grape cultivars of white, red and pink grape, as 28 interspecific hybrids and 2 Vitis vinifera L. popularly grown in Poland. Some of them were analyzed for the first time. A total of 49 polyphenolic compounds were identified by LC-PDA-QTOF/MS and quantified by UPLC-PDA-FL, as 26 anthocyanins, 9 flavonols and flavons, 7 phenolic acids, 6 flavan-3-ols, and 1 stilbene. The content of total polyphenols ranged from 1037.0 (Cascade cv.) to 5759.1mg/100gdm (Roesler cv.). However, the content of stilbene represented by trans resveratrol-3-glucoside was only 18.5-70.5mg/100gdm. Red grape cultivars like Roesler, Rothay and Swenson Red were characterized by the highest content of bioactive compounds and antioxidant activity (significantly more than 24, 12 and 53mmol TE/100gdm, by ABTS, FRAP and ORAC, respectively). Average total acidity and soluble solids for white (0.95g of tartaric acid in 100gfm and 17.1°Bx, respectively) and for red and pink (0.93g of tartaric acid in 100gfm and 17.4°Bx, respectively) cultivars were not significantly different (p>0.05).

Phenolic Rich Extract from Clinacanthus nutans Attenuates Hyperlipidemia-Associated Oxidative Stress in Rats

Clinacanthus nutans is used as traditional medicine in Asia but there are limited scientific studies to support its use. In this study, the stem and leaf of C. nutans were extracted using solvents of differing polarities, and their antioxidant capacities were determined using multiple antioxidant assays. The water and aqueous methanolic leaf extracts were further fractionated and their antioxidant capacities and phenolic compositions were tested. Furthermore, the efficacies of the water and aqueous methanolic leaf extracts were tested against hyperlipidemia-induced oxidative stress in rats. Serum and hepatic antioxidant and oxidative stress markers were tested after feeding the rats with high fat diet together with the extracts or simvastatin for 7 weeks. The results indicated that both leaf extracts attenuated oxidative stress through increasing serum antioxidant enzymes activity and upregulating the expression of hepatic antioxidant genes. Multiple phenolic compounds were detected in the extracts and fractions of C. nutans, although protocatechuic acid was one of the most abundant and may have contributed significantly towards the bioactivities of the extracts. However, synergistic effects of different phenolics may have contributed to the overall bioactivities. C. nutans can be a good source of functional ingredients for the management of oxidative stress-related diseases.

Stability of Trans-Resveratrol Encapsulated in a Protein Matrix Produced Using Spray Drying to UV Light Stress and Simulated Gastro-Intestinal Digestion

Trans-resveratrol has demonstrated the potential to provide both therapeutic and preventive activities against chronic diseases such as heart disease and cancer. The incorporation of trans-resveratrol into food products would allow for broader access of this bioactive compound to a larger population. However, this strategy is limited by instability of trans-resveratrol under environmental conditions and within the digestive system leading to isomerization of trans-resveratrol (bioactive form) to cis-resveratrol (bio-inactive form). Studies in the stabilization of trans-resveratrol into protein microparticles are presented. Trans-resveratrol was encapsulated using whey protein concentrate (WPC) or sodium caseinate (SC), with or without anhydrous milk fat (AMF). Binding of resveratrol and aromatic residues in protein was estimated utilizing the Stern-Volmer equation and the number of tryptophan residues. The stability of encapsulated resveratrol was evaluated after exposure to ultraviolet A (UVA) light and 3-stage in vitro digestion. After UVA light exposure, SC-based microcapsules maintained a higher trans:cis resveratrol ratio (0.63, P < 0.05) than WPC-based microcapsules (0.43) and unencapsulated resveratrol (0.49). In addition, encapsulation of resveratrol in both protein microparticles led to an increased digestive stability and bioaccessibility in comparison to unencapsulated resveratrol (47% and 23%, respectively, P < 0.05). SC-based microcapsules provided a higher digestive stability and bioaccessibility (86% and 81%; P < 0.05) compared to WPC-based microcapsules (71% and 68%). The addition of AMF to the microcapsules did not significantly change the in vitro digestion values. In conclusion, SC-based microencapsulation increased the stability of trans-resveratrol to UVA light exposure and simulated digestion conditions. This encapsulation-system-approach can be extended to other labile, bioactive polyphenols.

Characterization and comparison of phenolic composition, antioxidant capacity and instrumental taste profile of juices from different botanical origins

BACKGROUND

The European Union registered a consumption of about 10.7 billion litres of juices in 2011 and a great part of this amount is imported from other countries, which makes the monitoring of their quality essential. This work was aimed at mapping the quality of various juices from different botanical origins from instrumental taste, chemical marker and antioxidant capacity perspectives. It also characterized the individual phenolic composition of juices previously classified according to their antioxidant activity and total phenolic material level.

RESULTS

Overall, by using correlation analysis and chemometrics (HCA and PCA), data showed that total phenolics, specifically gallic acid, p-coumaric acid, anthocyanins, flavanols and flavonols, are the main contributors to the antioxidant activity. Elderberry and pomegranate juices presented the highest phenolic content and antioxidant activity. On the other hand, orange, apple and cranberry juices had the lowest levels of total phenolics and flavonoids, DPPH and CUPRAC.

CONCLUSION

The use of chemometrics coupled to ANOVA seems to be a suitable approach to evaluate the quality of fruit juices from different botanical origins. Additionally, the instrumental taste profile correlated well with the chemical composition and antioxidant capacity, showing its potential application in assessing the functionality of juices.

Tryptanthrin protects hepatocytes against oxidative stress via activation of the extracellular signal-regulated kinase/NF-E2-related factor 2 pathway

Tryptanthrin [6,12-dihydro-6,12-dioxoindolo-(2,1-b)-quinazoline], originally isolated from Isatidis radix, has been characterized as having anti-microbial and anti-tumor activities. It is well-known that excess oxidative stress is one of the major factors causing cell damage in the liver. This study investigated the cytoprotective effects and molecular mechanism of tryptanthrin against tert-butyl hydroperoxide (tBHP)-induced oxidative stress in human hepatocyte-derived HepG2 cells. Tryptanthrin pre-treatment blocked the reactive oxygen species production, mitochondrial dysfunction, and cell death induced by tBHP. Moreover, tryptanthrin reversed tBHP-induced GSH reduction. This study also confirmed the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) by tryptanthrin as a plausible molecular mechanism for its cytoprotective effects. Specifically, tryptanthrin treatment induced nuclear translocation and transactivation of Nrf2 as well as phosphorylation of extracellular signal-regulated kinase (ERK), a potential upstream kinase of Nrf2. Tryptanthrin also up-regulated the expression of the heme oxygenase 1 and glutamate-cysteine ligase catalytic subunits, which are representative target genes of Nrf2. Moreover, inhibitor of ERK was used to verify the important role of the ERK-Nrf2 pathway in the hepatoprotective effects of tryptanthrin. In conclusion, this study demonstrated that tryptanthrin protects hepatocytes against oxidative stress through the activation of the ERK/Nrf2 pathway in HepG2 cells.

Role of dietary pro-oxidants in the maintenance of health and resilience to oxidative stress

The average length of human life is increasing, but so does the incidence of age- and lifestyle-related diseases. Improving diet and lifestyle is a key strategy for lifelong health and underlying mechanisms may well include increasing resilience pathways. The purpose of this review is to highlight and evaluate novel mechanisms by which dietary pro-oxidants, including bioactive phytochemicals and fatty acids, increase reactive oxygen species (ROS) concentrations just enough to activate transcription factor activation of nuclear factor erythroid 2 related factor 2 (Nrf-2) and heat shock factor (HSF), leading to an increase in levels of antioxidant enzymes and heat shock proteins that protect against the damaging effects of ROS. An increasing number of in vivo studies have now shown that dietary pro-oxidant compounds can increase the production of such resilience products. In most studies, dietary pro-oxidants normalized levels of antioxidant enzymes that were decreased by a range of different challenges, rather than raising levels of resilience products per se. Also, it is important to consider that the antioxidant response can be different for different organs. For future studies, however, the measurement of resilience markers may significantly improve our ability to prove the efficacy by which dietary bioactives with pro-oxidant capacities improve lifelong health.

Characterization of conventional, biodynamic, and organic purple grape juices by chemical markers, antioxidant capacity, and instrumental taste profile

The objectives of this study were to characterize organic, biodynamic, and conventional purple grape juices (n = 31) produced in Europe based on instrumental taste profile, antioxidant activity, and some chemical markers and to propose a multivariate statistical model to analyze their quality and try to classify the samples from the 3 different crop systems. Results were subjected to ANOVA, correlation, and regression analysis, principal component analysis (PCA), hierarchical cluster analysis (HCA), soft independent modeling of class analogy (SIMCA), and partial least-squares discriminant analysis (PLSDA). No statistical significant differences (P > 0.05) were observed among juices from the 3 crop systems. Using PCA and HCA, no clear separation among crop systems was observed, corroborating the ANOVA data. However, PCA showed that the producing region highly affects the chemical composition, electronic tongue parameters, and bioactivity of grape juices. In this sense, when organic and biodynamic were grouped as "nonconventional" juices, SIMCA model was able to discriminate 12 out of 13 organic/biodynamic juices and 17 out of 18 conventional juices, presenting an efficiency of 93.5%, while 11 out of 13 non-conventional and 100% conventional grape juices were correctly classified using PLSDA. The use of electronic tongue and the determination of antioxidant properties and major phenolic compounds have shown to be a quick and accurate analytical approach to assess the quality of grape juices.

Optimization of β-cyclodextrin-based flavonol extraction from apple pomace using response surface methodology

The present study investigated five cyclodextrins (CDs) for the extraction of flavonols from apple pomace powder and optimized β-CD based extraction of total flavonols using response surface methodology. A 2(3) central composite design with β-CD concentration (0-5 g 100 mL(-1)), extraction temperature (20-72 °C), extraction time (6-48 h) and second-order quadratic model for the total flavonol yield (mg 100 g(-1) DM) was selected to generate the response surface curves. The optimal conditions obtained were: β-CD concentration, 2.8 g 100 mL(-1); extraction temperature, 45 °C and extraction time, 25.6 h that predicted the extraction of 166.6 mg total flavonols 100 g(-1) DM. The predicted amount was comparable to the experimental amount of 151.5 mg total flavonols 100 g(-1) DM obtained from optimal β-CD based parameters, thereby giving a low absolute error and adequacy of fitted model. In addition, the results from optimized extraction conditions showed values similar to those obtained through previously established solvent based sonication assisted flavonol extraction procedure. To the best of our knowledge, this is the first study to optimize aqueous β-CD based flavonol extraction which presents an environmentally safe method for value-addition to under-utilized bio resources.

In vitro studies on the relationship between the antioxidant activities of some berry extracts and their binding properties to serum albumin

The aim of this study was to investigate the possibility to use the bioactive components from cape gooseberry (Physalis peruviana), blueberry (Vaccinium corymbosum), and cranberry (Vaccinium macrocarpon) extracts as a novel source against oxidation in food supplementation. The quantitative analysis of bioactive compounds (polyphenols, flavonoids, flavanols, carotenoids, and chlorophyll) was based on radical scavenging spectrophometric assays and mass spectrometry. The total phenolic content was the highest (P < 0.05) in water extract of blueberries (46.6 ± 4.2 mg GAE/g DW). The highest antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay and Cupric reducing antioxidant capacity were in water extracts of blueberries, showing 108.1 ± 7.2 and 131.1 ± 9.6 μMTE/g DW with correlation coefficients of 0.9918 and 0.9925, and by β-carotene linoleate assay at 80.1 ± 6.6 % with correlation coefficient of 0.9909, respectively. The water extracts of berries exhibited high binding properties with human serum albumin in comparison with quercetin. In conclusion, the bioactive compounds from a relatively new source of gooseberries in comparison with blueberries and cranberries have the potential as food supplementation for human health. The antioxidant and binding activities of berries depend on their bioactive compounds.