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Increased intake of dietary antioxidants such as anthocyanins, which are enriched in colourful fruits, is a promising alternative to reduce the risk of degenerative diseases such as Alzheimer’s Disease (AD). Since Amyloid β (Aβ) is one of the key components contributing to AD pathology, probably by reactive oxygen species (ROS) induction, this study investigated the preventive effect of anthocyanin-rich bilberry extract (BE) and its anthocyanin fraction (ACN) on ROS generation and cell toxicity. The results showed a significant and concentration-dependent decrease in neuroblastoma cell (SH-SY5Y) viability by BE or ACN, whereas no cell toxicity was observed in HeLa cells. Incubation with BE and ACN for 24 h diminished the generation of induced ROS levels in SH-SY5Y and HeLa cells. In addition, low concentrations of BE (1–5 µg/mL) showed protective effects against Aβ-induced cytotoxicity in SH-SY5Y cells. In conclusion, our results suggest antioxidant and protective effects of BE and ACN, which could potentially be used to delay the course of neurodegenerative diseases such as AD. Further studies are needed to clarify the high potential of anthocyanins and their in vivo metabolites on neuronal function.

Although numerous studies imply a correlation between chemical contamination and an impaired immunocompetence of wildlife populations, the assessment of immunomodulatory modes of action is currently not covered in the regulatory requirements for the approval of new substances. This is not least due to the complexity of the immune system and a lack of standardised methods and validated biomarkers. To tackle this issue, in this study, the transcriptomic profiles of zebrafish embryos were analysed in response to the immunosuppressive compound clobetasol propionate, a synthetic glucocorticoid, and/or the immunostimulatory compound imiquimod (IMQ), a TLR-7 agonist. Using IMQ, known for its potential to induce psoriasis-like effects in mice and human, this study additionally aimed at evaluating the usability of the zebrafish embryo model as an alternative and 3R conform system for the IMQ-induced psoriasis mouse model. Our study substantiates the suitability of previously proposed genes as possible biomarkers for immunotoxicity, such as socs3, nfkbia, anxa1c, fkbp5 and irg1l. Likewise, however, our findings indicate that these genes may be less suitable to distinguish a suppressive from stimulating fashion of action. In contrast, based on a differential regulation in opposite direction in response to both compounds, krt17, rtn4a, and1, smhyc1 and gmpr were identified as potential novel biomarkers with said power to differentiate. Observed IMQ-induced alterations in the expression of genes previously associated with the pathogenesis of psoriasis such as krt17, nfkbia, parp1, pparg, nfil3–6, per2, stat4, klf2, rtn4a, anxa1c and nr1d2 indicate the inducibility of psoriatic effects in the zebrafish embryo.Our work contributes to the establishment of an approach for a 3R-compliant investigation of immunotoxic mechanisms of action in aquatic vertebrates. The validated and newly identified biomarker candidates of specific immunotoxic effects can be used in future studies in the context of environmental hazard assessment of substances or also for human-relevant immunotoxicological questions.

Isoeugenol (2-methoxy-4-(1-propenyl)phenol) has been recently classified as possibly carcinogenic to humans (Group 2B) by the International Agency for Research on Cancer (IARC). This study conducted an analysis of isoeugenol in common herbs and spices, including basil, cinnamon, ginger, and nutmeg, using 1H nuclear magnetic resonance (NMR) spectrometry. Additionally, over 1300 coffee samples were analysed by 1H-NMR for isoeugenol, but it was not detected in any of the analysed samples. Various essential oils, including nutmeg, basil, clove, sweet flag, and ylang-ylang oils, were examined for isoeugenol content. Out of the twelve nutmeg oils tested, four contained isoeugenol, with concentrations ranging from 3.68 ± 0.09 g/kg to 11.2 ± 0.10 g/kg. However, isoeugenol was not detected in the essential oils of calamus, basil, ylang-ylang, and clove using NMR spectrometry. These findings warrant critical evaluation of the previous literature, given reports of high isoeugenol levels in some of these matrices. A toxicological assessment has determined that there is no risk to human health by exposure to isoeugenol via nutmeg essential oils.

Abstract Liver cancer is one of the most frequent tumor entities worldwide, which is causally linked to viral infection, fatty liver disease, life-style factors and food-borne carcinogens, particularly aflatoxins. Moreover, genotoxic plant toxins including phenylpropenes are suspected human liver carcinogens. The phenylpropene methyleugenol (ME) is a constituent of essential oils in many plants and occurs in herbal medicines, food, and cosmetics. Following its uptake, ME undergoes Cytochrome P450 (CYP) and sulfotransferase 1A1 (SULT1A1)-dependent metabolic activation, giving rise to DNA damage. However, little is known about the cellular response to the induced DNA adducts. Here, we made use of different SULT1A1-proficient cell models including primary hepatocytes that were treated with 1′-hydroxymethyleugenol (OH-ME) as main phase I metabolite. Firstly, mass spectrometry showed a concentration-dependent formation of N 2-MIE-dG as major DNA adduct, strongly correlating with SULT1A1 expression as attested in cells with and without human SULT1A1. ME-derived DNA damage activated mainly the ATR-mediated DNA damage response as shown by phosphorylation of CHK1 and histone 2AX, followed by p53 accumulation and CHK2 phosphorylation. Consistent with these findings, the DNA adducts decreased replication speed and caused replication fork stalling. OH-ME treatment reduced viability particularly in cell lines with wild-type p53 and triggered apoptotic cell death, which was rescued by pan-caspase-inhibition. Further experiments demonstrated mitochondrial apoptosis as major cell death pathway. ME-derived DNA damage caused upregulation of the p53-responsive genes NOXA and PUMA, Bax activation, and cytochrome c release followed by caspase-9 and caspase-3 cleavage. We finally demonstrated the crucial role of p53 for OH-ME triggered cell death as evidenced by reduced pro-apoptotic gene expression, strongly attenuated Bax activation and cell death inhibition upon genetic knockdown or pharmacological inhibition of p53. Taken together, our study demonstrates for the first time that ME-derived DNA damage causes replication stress and triggers mitochondrial apoptosis via the p53-Bax pathway.

Furan and 2-methylfuran (2-MF) are food contaminants that are classified as potentially carcinogenic to humans. The main source of exposure for adults via food is coffee consumption. Furan and 2-MF are volatile, which complicates exposure assessment because their content measured in food prior to consumption does not afford a reliable dosimetry. Therefore, other ways of exposure assessment need to be developed, preferably by monitoring exposure biomarkers, e.g., selected metabolites excreted in urine. In this study, cis-2-buten-1,4-dial (BDA)-derived urinary furan metabolites Lys-BDA (l-2-amino-6-(2,5-dihydro-2-oxo-1H-pyrrol-1-yl)hexanoic acid), AcLys-BDA (l-2-(acetylamino)-6-(2,5-dihydro-2-oxo-1H-pyrrol-1-yl)hexanoic acid) and GSH-BDA (N-[4-carboxy-4-(3-mercapto-1H-pyrrol-1-yl)-1-oxobutyl]-l-cysteinyl-glycine cyclic sulfide), as well as acetyl acrolein (AcA, 2-oxo-pent-2-enal)-derived metabolites Lys-AcA (l-2-(acetylamino)-6-(2,5-dihydro-5-methyl-2-oxo-1H-pyrrol-1-yl)-hexanoic acid) and AcLys-AcA (l-2-amino-6-(2,5-dihydro-5-methyl-2-oxo-1H-pyrrol-1-yl)-hexanoic acid) and their stable isotopically labeled analogs, were synthesized and characterized through NMR and MS, and a stable isotope dilution analysis (SIDA) with UPLC-ESI-MS/MS was established. As a proof of concept, urinary samples of a four-day human intervention study were used. In the frame of this study, ten subjects ingested 500 mL of coffee containing 0.648 µmol furan and 1.059 µmol 2-MF. Among the furan metabolites, AcLys-BDA was the most abundant, followed by Lys-BDA and GSH-BDA. Exposure to 2-MF via the coffee brew led to the formation of Lys-AcA and AcLys-AcA. Within 24 h, 89.1% of the ingested amount of furan and 15.4% of the ingested amount of 2-MF were detected in the urine in the form of the investigated metabolites. Therefore, GSH-BDA, Lys-BDA, AcLys-BDA, Lys-AcA and AcLys-AcA may be suitable as short-term-exposure biomarkers of furan and 2-MF exposure.

Grape pomace (GP) has an added value because of its contribution to carbon (C) and nitrogen (N) in soils when applied as an organic fertilizer. Macronutrients from GP are translocated into the soil after amendment, but little is known about the factors that may influence the mobility of C, N and bioactive molecules, i.e., polyphenols, in the soil column. We investigated the mobility of the macronutrient content of GP, derived from two red (Dornfelder and Pinot noir) and two white grape varieties (Riesling and Pinot blanc). For that, three different soils (loamy sand RefeSol01A, silt loam RefeSol02A and a vineyard soil) were evaluated in a column model using a GP application rate of 30 t ha−1. The three-step lab-scale approach included the analysis of total C, N and polyphenols expressed as total polyphenolic content (TPC) in: (a) the fresh GP, representing the total amount of C, N and TPC; (b) the mobility with rainwater, representing the aqueous extractable fraction and (c) the mobility in the soil column and leaching potential. Our results showed that total C/N ratios were wider in the white GP varieties compared with the red ones. Higher TPC values were measured in Dornfelder and Pinot noir compared with white varieties. Analysis of the water-extractable fraction showed that the C recovery may reach up to 48% in Pinot blanc, which also corresponds to the highest N contribution. Extractable polyphenols were higher in the red compared with the white varieties by a factor of 2.4. C and N were mobilized with rainwater from the GP through the soil column. However, the application rate used in the experiment was not indicative of an accumulation in the soil. Compared with the control (no GP application), C values were significantly higher in the leachates from GP-treated soils, in contrast to N values. Up to 10% of the TPC of the pomace was leached into the soil. The TPC recovery in the soils strongly depended on the combination of soil type and GP variety. Generally, the sandy and more acidic soil showed an even distribution of phenolics with a high recovery rate (up to 92%) compared with more neutral and silty soil. Most of the polyphenol content could accumulate in the upper soil layer (0–10 cm). These results provide the first insights on the mobility of macronutrients in the soil using a column model and point out the need to relate those experiments to soil and GP properties in order to avoid the accumulation of nutrients in soil or mobility to adjacent ecosystems.

Lignans are secondary plant constituents with dibenzylbutane skeletons found in cereals, oilseeds, and nuts. Two members of this class, syringaresinol (Syr) and secoisolariciresinol (Seco), occur at relatively high levels in cereals and processed food products as well as in coniferous trees. In vitro studies have shown that Seco and its metabolites enterodiol (END) and enterolactone (ENL), which are formed by intestinal microbes, exhibit strong antioxidant activity because of their phenolic character. The biological activity and discussion of dietary supplementation with these substances led to questions about the potential adverse health effects of these compounds, which are explored here. Syr and the metabolites END and ENL were investigated by combining structural information generated in silico with practical testing in vitro. An in silico structure-activity analysis was performed using ToxTree and NexusPrediction to suggest plausible mechanisms of toxicity and estimate toxicological endpoints of these compounds. Structural alerts were generated based on the presence of phenolic units with coordinating substituents that could potentially form quinoid structures, promote reactive oxygen species (ROS) formation, bind to cellular structures, or damage chromosomes. To assess the in silico results, the cytotoxicity and genotoxic potential of the studied compounds were tested in vitro using the resazurin reduction and comet assays, respectively. Incubating HepG2 and HT29 cells for 1 h or 24 h with 0–100 μM Syr, END, or ENL induced no cytotoxic effects. Additionally, even the highest tested concentrations of END and ENL showed no modulation of background and total DNA damage. The initial in silico screen thus generated structural alerts linked to toxicological endpoints, but experimental assessments of the studied compounds revealed no detectable toxicity, demonstrating the need for individual mechanistic experimental verification of in silico predictions. This approach makes it possible to connect known biological activity, such as reported antioxidative effects, to underlying mechanisms such as proton abstraction or donation. This in turn can yield insights – for example, that a compound's tendency to act as a pro- or anti-oxidant (and hence to exert adverse or beneficial health effects) may depend on its concentration and the cellular state.

Abstract Recently, we demonstrated that the consumption of a bolus of bilberry extract modulates the transcription of Nrf2-regulated genes in peripheral blood lymphocytes (PBL) of healthy volunteers, accompanied by decreased DNA-damage. In the present study, we addressed the question whether consumption of consumer-relevant amounts of anthocyanin-rich beverages can achieve similar effects. The impact of three different anthocyanin-rich beverages on Nrf2-dependent gene transcription as well as and the status of DNA-damage in whole blood was investigated. After a polyphenol-reduced diet, five healthy male subjects consumed a bolus (700 mL) of respective test beverages with blood sampling up to 8 h after intake. All beverages affected the transcription of Nrf2, HO-1 and NQO-1, but showed different potencies and persistence of effects. Consumption of red fruit juice significantly reduced total DNA strand breaks (with formamidopyrimidine-DNA-glycosylase-(fpg) treatment) after 8 h in blood samples of the volunteers, suggesting antioxidant and DNA protective effects, albeit transcript levels of Nrf2-dependent genes had reached the basal state. The amount of basic DNA strand breaks (damage without oxidative DNA strand breaks) remained unchanged during the monitoring period. In contrast, a beverage prepared from grape skin extract significantly increased basic and total DNA strand breaks 2 h after intake, underlining the necessity of further investigations regarding composition, safety and consumer´s acceptance of respective products to exclude undesired adverse effects. Consumption of a bolus of anthocyanin-rich beverages affected Nrf2 and Nrf2-dependent gene transcription in human PBL and DNA integrity, which is indicative for systemic effects.

Polyphenols are a diverse and widely distributed class of secondary metabolites, which possess numerous beneficial properties including a modulation of glucose and lipid metabolism. This placebo-controlled human intervention study was performed to explore effects of polyphenol-rich beverage (PRB) uptake on lipid metabolism, as well as DNA integrity. In this case, 36 healthy men were randomly divided to consume either 750 mL of a PRB (containing 51% chokeberry, cranberry, and pomegranate) or a placebo drink daily for eight weeks. Only PRB consumption was found to decrease fat and protein intakes significantly compared to the preceding one-week washout period. During the intervention with PRB an increased fat-free mass was shown after four weeks, whereas a significant elevation in body weight and leptin was observed in placebo group. Blood lipids were not significantly altered after PRB consumption, while triglyceride levels increased after placebo drink intake. In platelets, a significant inhibition of phosphodiesterase (PDE) activity was observed, more pronounced in test group. Consuming the PRB decreased total DNA strand breaks in whole blood as well as H2O2-induced breaks in isolated lymphocytes. Overall, our study suggested beneficial effects on lipid metabolism by reduced energy intake, modulation of biomarkers such as PDE activity and improved DNA integrity associated with PRB consumption.

The use of the flowers (blossoms) of the coffee plant (genus Coffea) has been neglected over the years, as the focus has primarily been on the cost-efficient production of coffee beans. Because of societal changes and economic pressures, there is an increasing demand for sustainability, so the focus has also widened towards the various by-products of the coffee production. The coffee flower is a by-product because it can be harvested following pollination without any risk to the bean production. The coffee flower can be used as a whole or as floral water in some food and cosmetic products. The flower can also be prepared as a tea-like beverage with hot water infusion. Another side-chain product in coffee plantations is the so-called coffee flower honey, which is rarely monofloral due to the short flowering period. To date, there have been few studies on coffee flowers and their sensory characterization. In this work, various compounds in Coffea arabica, C. canephora, and C. liberica flowers were identified and quantified by high-performance liquid chromatography (HPLC) with diode array detection (DAD), nuclear magnetic resonance spectroscopy (NMR), and near-infrared (NIR) spectroscopy. Caffeine, chlorogenic acids, organic acids, trigonelline, and sugars were quantified. Additionally, the sensory testing of coffee flower infusions according to the German norm DIN 10 809 was performed. With the acquired data, a principal component analysis (PCA) was performed in which hay, hops, sage, dried apricot, and honey were identified as major flavor descriptors in addition to the floral coffee flower flavors. The coffee flower is judged as a promising ingredient, which needs to be further assessed regarding its possible approval within the novel food regulations of the European Union.

Background: In the past 60 years, Cannabis sativa L. has been an object of increasing interest because of the psychotropic effects of some of its constituents. These effects mainly arise from the cannabinoid Δ9-tetrahydrocannabinol (Δ9-THC). C. sativa species also synthesize and accumulate the non-psychotropic compound cannabidiol (CBD). Due to their therapeutic potential, both cannabinoids are an object of medical research and drug development. More recently, CBD has received increasing interest as an ingredient in electronic cigarette liquids (e-liquids). This trend may have been reinforced by health and disease-related claims, often based on clinical studies, which are used to advertise CBD. CBD liquids may be based on full-spectrum hemp extracts, CBD isolates, or synthetic CBD, all of which may contain some residual levels of Δ9-THC from either natural content (in the extracts) or from possible degradation of CBD to Δ9-THC, which may occur during storage. There is uncertainty about safety regarding the consumption of CBD (and Δ9-THC) in e-liquids. The aim of this publication was to present an approach for a toxicological risk assessment of CBD and Δ9-THC relevant to e-liquids by using the benchmark dose (BMD) approach. Materials and Methods: Before an analysis to estimate a reference dose (RfD) for both cannabinoids, a systematic review of dose-response data was conducted. The data obtained were analyzed using the BMD approach to derive a benchmark dose lower confidence limit (BMDL). The BMDL was used as a point of departure to estimate the RfD. Results: No adequate human data suitable for dose-response modeling were identified. Based on animal data, the RfD values for the most sensitive endpoints were selected. For CBD, an RfD for acute exposure of 1 mg/kg body weight (bw) was estimated. For Δ9-THC, an acute RfD was found to be 0.006 mg/kg bw. Additionally, the RfD for chronic exposure to CBD was estimated to be 4 mg/kg bw per day. The respective endpoints for CBD were a reduction in norepinephrine turnover and a reduction in uterus weight. The endpoint for Δ9-THC was a change in blood pressure. Conclusions: Because of the limited availability and quality of dose-response data, it cannot be excluded that the estimated RfD values might be afflicted with considerable uncertainties. Therefore, it is recommended to conduct further research on dose-response data, preferably from human studies.

Polyphenols show a spectrum of bioactive effects, including an influence on lipid metabolism. In this study, we performed activity-guided fractionations of black chokeberry (aronia), cranberry, and pomegranate extracts to identify the biologically active compounds. The extracts were prepared from fruit juice concentrates with the adsorbent resin Amberlite XAD-7 and were separated into a copigment and an anthocyanin fraction, followed by fractionation into a polymer and monomeric fraction by means of hexane precipitation. For further fractionation of the cranberry and pomegranate copigment fractions, high-performance countercurrent chromatography (HPCCC) was used. The compounds in each fraction were identified by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS), and the quantification was performed by ultra high-performance liquid chromatography-diode array detector (UHPLC-DAD) analyses. Each of the (sub-)fractions was tested in three in vitro assays: phosphodiesterase 3B (PDE) activity, lipid accumulation, and lipolysis in 3T3-L1 cells. The results showed that various fractions and subfractions can inhibit lipid accumulation and PDE activity as well as increase lipolysis, particularly copigments. Overall, our results indicate an influence of polyphenol-rich (sub-)fractions on the lipid metabolism.

Winery by-products arise in high amounts during winemaking processes. Hence, recovery alternatives are of great interest. In this study, effects of extracts from winery by-products (Vitis vinifera L. cv. Riesling) on mitochondrial functions in human hepatocellular carcinoma (HepG2) cells were examined. Polyphenolic profiles of pomace (PE), stem (SE), vine leaf (VLE), and vine shoot extracts (VSE) were characterized by HPLC-UV/Vis-ESI-MS/MS. The extracts induced dose-dependent cytotoxic effects (PE > SE > VLE > VSE). VSE showed protective effects regarding modulation of tert-butyl hydroperoxide (TBH)-induced intracellular reactive oxygen species (ROS) levels. PE, SE and VLE increased the mitochondrial membrane potential (MMP), whereas VSE decreased it owing to mildly impaired mitochondrial respiration. Cells may try to compensate reduced respiration chain complex activities by increasing the mitochondrial mass, as indicated by enhanced citrate synthase activity and mRNA expression levels after VSE incubation. Thus, winery by-products represent interesting sources of bioactive compounds that exert positive or negative effects on mitochondrial functions.

With a yearly production of about 39 million tons, brewer’s spent grain (BSG) is the most abundant brewing industry byproduct. Because it is rich in fiber and protein, it is commonly used as cattle feed but could also be used within the human diet. Additionally, it contains many bioactive substances such as hydroxycinnamic acids that are known to be antioxidants and potent inhibitors of enzymes of glucose metabolism. Therefore, our study aim was to prepare different extracts—A1-A7 (solid-liquid extraction with 60% acetone); HE1-HE6 (alkaline hydrolysis followed by ethyl acetate extraction) and HA1-HA3 (60% acetone extraction of alkaline residue)—from various BSGs which were characterized for their total phenolic (TPC) and total flavonoid (TFC) contents, before conducting in vitro studies on their effects on the glucose metabolism enzymes α-amylase, α-glucosidase, dipeptidyl peptidase IV (DPP IV), and glycogen phosphorylase α (GPα). Depending on the extraction procedures, TPCs ranged from 20–350 µg gallic acid equivalents/mg extract and TFCs were as high as 94 µg catechin equivalents/mg extract. Strong inhibition of glucose metabolism enzymes was also observed: the IC50 values for α-glucosidase inhibition ranged from 67.4 ± 8.1 µg/mL to 268.1 ± 29.4 µg/mL, for DPP IV inhibition they ranged from 290.6 ± 97.4 to 778.4 ± 95.5 µg/mL and for GPα enzyme inhibition from 12.6 ± 1.1 to 261 ± 6 µg/mL. However, the extracts did not strongly inhibit α-amylase. In general, the A extracts from solid-liquid extraction with 60% acetone showed stronger inhibitory potential towards a-glucosidase and GPα than other extracts whereby no correlation with TPC or TFC were observed. Additionally, DPP IV was mainly inhibited by HE extracts but the effect was not of biological relevance. Our results show that BSG is a potent source of α-glucosidase and GPα inhibitors, but further research is needed to identify these bioactive compounds within BSG extracts focusing on extracts from solid-liquid extraction with 60% acetone.

Background: This study investigated the effects of an aronia juice-based food supplement on background and total DNA strand breaks in whole blood, and on H2O2-induced DNA strand breaks in isolated peripheral blood lymphocytes. Methods: Ninety-one healthy volunteers were randomly selected to consume either the food supplement (2 × 25 mL drinking ampules, n = 45) or no supplement (n = 46) daily for eight weeks. Results: Background DNA strand breaks decreased significantly after four and eight weeks of supplement consumption, compared to baseline (p < 0.05), but the overall effect was low, and neither group showed a decrease in total DNA strand breaks. Conversely, supplement consumption clearly reduced H2O2-induced DNA strand breaks ex vivo (p < 0.001), with statistically significant reductions after four and eight weeks, compared to the control group (p < 0.05). Conclusions: Thus, although consuming antioxidant supplements might produce only marginal immediate benefits under healthy conditions, potential preventive effects warrant further investigation.

Acrylamide is probably carcinogenic to humans (International Agency for Research on Cancer, group 2A) with major occurrence in heated, mainly carbohydrate-rich foods. For roasted coffee, a European Union benchmark level of 400 µg/kg acrylamide is of importance. Regularly, the acrylamide contents are controlled using liquid chromatography combined with tandem mass spectrometry (LC–MS/MS). This reference method is reliable and precise but laborious because of the necessary sample clean-up procedure and instrument requirements. This research investigates the possibility of predicting the acrylamide content from proton nuclear magnetic resonance (NMR) spectra that are already recorded for other purposes of coffee control. In the NMR spectrum acrylamide is not directly quantifiable, so that the aim was to establish a correlation between the reference value and the corresponding NMR spectrum by means of a partial least squares (PLS) regression. Therefore, 40 commercially available coffee samples with already available LC–MS/MS data and NMR spectra were used as calibration data. To test the accuracy and robustness of the model and its limitations, 50 coffee samples with extreme roasting degrees and blends were additionally prepared as the test set. The PLS model shows an applicability for the varieties Coffea arabica and C. canephora, which were medium to very dark roasted using drum or infrared roasters. The root mean square error of prediction (RMSEP) is 79 µg/kg acrylamide (n = 32). The current PLS model is judged as suitable to predict the acrylamide values of commercially available coffee samples.

Polyphenols are considered protective against diseases associated with oxidative stress. Short-term intake of an anthocyanin-rich fruit juice resulted in significantly reduced deoxyribonucleic acid (DNA) strand-breaks in peripheral blood lymphocytes (PBLs) and affected antioxidant markers in healthy volunteers. Consequently, effects of long-term consumption of fruit juice are of particular interest. In focus was the impact on nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2), the Nrf2-regulated genes NAD(P)H quinone oxidoreductase 1 (NQO-1) and heme oxygenase 1 (HO-1) as well as effects on the gut microbiota. In a nine-week placebo-controlled intervention trial with 57 healthy male volunteers, consumption of anthocyanin-rich juice significantly increased NQO-1 and HO-1 transcript levels in PBLs compared to a placebo beverage as measured by real-time polymerase chain reaction (PCR). Three Nrf2-promotor single nucleotide polymorphisms (SNPs), analyzed by pyrosequencing, indicated an association between individual Nrf2 transcript levels and genotype. Moreover, the Nrf2 genotype appeared to correlate with the presence of specific microbial organisms identified by 16S-PCR and classified as Spirochaetaceae. Furthermore, the microbial community was significantly affected by the duration of juice consumption and intake of juice itself. Taken together, long-term consumption of anthocyanin-rich fruit juice affected Nrf2-dependent transcription in PBLs, indicating systemic effects. Individual Nrf2 genotypes may influence the antioxidant response, thus requiring consideration in future intervention studies focusing on the Nrf2 pathway. Anthocyanin-rich fruit juice had an extensive impact on the gut microbiota.

Red fruits and their juices are rich sources of polyphenols, especially anthocyanins. Some studies have shown that such polyphenols can inhibit enzymes of the carbohydrate metabolism, such as α-amylase and α-glucosidase, that indirectly regulate blood sugar levels. The presented study examined the in vitro inhibitory activity against α-amylase and α-glucosidase of various phenolic extracts prepared from direct juices, concentrates, and purees of nine different berries which differ in their anthocyanin and copigment profile. Generally, the extracts with the highest phenolic content—aronia (67.7 ± 3.2 g GAE/100 g; cyanidin 3-galactoside; chlorogenic acid), pomegranate (65.7 ± 7.9 g GAE/100 g; cyanidin 3,5-diglucoside; punicalin), and red grape (59.6 ± 2.5 g GAE/100 g; malvidin 3-glucoside; quercetin 3-glucuronide)—showed also one of the highest inhibitory activities against α-amylase (326.9 ± 75.8 μg/mL; 789.7 ± 220.9 μg/mL; 646.1 ± 81.8 μg/mL) and α-glucosidase (115.6 ± 32.5 μg/mL; 127.8 ± 20.1 μg/mL; 160.6 ± 68.4 μg/mL) and, partially, were even more potent inhibitors than acarbose (441 ± 30 μg/mL; 1439 ± 85 μg/mL). Additionally, the investigation of single anthocyanins and glycosylated flavonoids demonstrated a structure- and size-dependent inhibitory activity. In the future in vivo studies are envisaged.

We have investigated urine samples after coffee consumption using targeted and untargeted approaches to identify furan and 2-methylfuran metabolites in urine samples by UPLC-qToF. The aim was to establish a fast, robust, and time-saving method involving ultra-performance liquid chromatography-quantitative time-of-flight tandem mass spectrometry (UPLC-qToF-MS/MS). The developed method detected previously reported metabolites, such as Lys-BDA, and others that had not been previously identified, or only detected in animal or in vitro studies. The developed UPLC-qToF method detected previously reported metabolites, such as lysine-cis-2-butene-1,4-dial (Lys-BDA) adducts, and others that had not been previously identified, or only detected in animal and in vitro studies. In sum, the UPLC-qToF approach provides additional information that may be valuable in future human or animal intervention studies.

Phosphodiesterases (PDEs) are essential enzymes for the regulation of pathways mediated by cyclic adenosine monophosphate (cAMP). Secondary plant compounds like anthocyanins (ACs) can inhibit PDE activity and, consequently, may be beneficial for lipid metabolism. This study investigated 18 AC-rich juice extracts and pure reference compounds from red fruits for potential inhibitory effects on PDE 3B activity. Extracts were obtained through adsorption on Amberlite® XAD 7 resin. Based on this screening, the chokeberry, blueberry, pomegranate, and cranberry extracts were active, with half maximal inhibitory concentrations (IC50) ranging from 163 ± 3 µg/mL to 180 ± 3 µg/mL. The ACs in these extracts, peonidin-3-glucoside and cyanidin-3-arabinoside, were the most active single compounds (IC50 = 56 ± 20 µg/mL, 108 ± 6 µg/mL). All extracts comprised high amounts of phenolic compounds, as determined by the Folin–Ciocalteu assay, ranging from 39.8 ± 1.5 to 73.5 ± 4.8 g gallic acid equivalents (GAE)/100 g extract. Pomegranate and chokeberry extracts exhibited the largest amounts of polyphenols (72.3 ± 0.7 g GAE/100 g, 70.6 ± 4.1 g GAE/100 g, respectively). Overall, our results showed that fruit juice extracts and their ACs can inhibit PDE activity. Any potential health benefits in vivo will be investigated in the future.

An activity-guided search for compounds influencing glucose metabolism in extracts from aronia (Aronia melanocarpa, A.), pomegranate (Punica granatum L., P.), and red grape (Vitis vinifera, RG) was carried out. The three extracts were fractionated by means of membrane chromatography to separate the anthocyanins from other noncolored phenolic compounds (copigments). In addition, precipitation with hexane was performed to isolate the polymers (PF). The anthocyanin and copigment fractions (AF, CF) of aronia, pomegranate, and red grape were furthermore fractionated with high-performance countercurrent chromatography (HPCCC) and the subfractions were characterized by HPLC-PDA-MS/MS analyses. Each of the (sub-)fractions was examined by in vitro-tests, i.e., the inhibition of the activity of α-amylase and α-glucosidase. On the basis of this screening, several potent inhibitors of the two enzymes could be identified, which included flavonols (e.g., quercetin), ellagitannins (e.g., pedunculagin), and anthocyanins (e.g., delphinidin-3-glucoside and petunidin-3-glucoside). In the α-glucosidase assay all of the examined fractions and subfractions of the fruit extracts were more active than the positive control acarbose.

Winery by-products, including pomace, stem, vine leaves and shoots, arise in high amounts during the wine-making process. Due to high contents of secondary plant metabolites, such as polyphenols, their usage in the food, cosmetics and pharmaceutical industry is possible. In this study, we investigated effects of an extract prepared from vine shoots (Vitis vinifera L. cv. Riesling) on riboflavin-induced DNA damage in human hepatocellular carcinoma cells HepG2 by comet assay. Significant decreases of DNA damages were detected after 2 h and 24 h extract incubation at concentration ranges of 1 to 30 µg/mL (2 h) and 1 to 10 µg/mL (24 h), respectively. These effects may be attributable to polyphenolic compounds, which has to be further investigated.

The vitamin B3 (niacin) is present in various foods. During roasting of green coffee beans, niacin is formed from the alkaloid trigonelline. Therefore, we established a novel fast and sensitive HPLC-MS/MS method to determine niacin in coffee brews from five commercially available coffee samples. Additionally, we investigated the influence of the brewing method, brewing temperature, and degree of roasting on niacin contents. In the respective coffee brews, we were able to show that the content of niacin in coffee beverages is not only affected by the degree of roasting, but also by the extraction performance of different brewing methods to a lesser extent.

Background: Phosphodiesterases (PDEs) play a major role in the regulation of cyclic adenosine monophosphate (cAMP)- and cyclic guanosine monophosphate (cGMP)-mediated pathways. Their inhibitors exhibit anti-inflammatory, vasodilatory and antithrombotic effects. Therefore, consumption of foods with PDE-inhibiting potential may possess beneficial influence on the risk of cardiovascular diseases. Methods: Four plant extracts (Arbutus unedo, Camellia sinensis, Cynara scolymus, Zingiber officinale) with promising ingredient profiles and physiological effects were tested for their ability to inhibit cAMP-specific PDE in vitro in a radioactive assay. Results: Strawberry tree fruit (Arbutus unedo) and tea (Camellia sinensis) extracts did not inhibit PDE markedly. Alternatively, artichoke (Cynara scolymus) extract had a significant inhibitory influence on PDE activity (IC50 = 0.9 ± 0.1 mg/mL) as well as its flavone luteolin (IC50 = 41 ± 10 μM) and 3,4-dicaffeoylquinic acid (IC50 > 1.0 mM). Additionally, the ginger (Zingiber officinale) extract and one of its constituents, [6]-gingerol, significantly inhibited PDE (IC50 = 1.7 ± 0.2 mg/mL and IC50 > 1.7 mM, respectively). Crude fractionation of ginger extract showed that substances responsible for PDE inhibition were in the lipoid fraction (IC50 = 455 ± 19 μg/mL). Conclusions: A PDE-inhibitory effect was shown for artichoke and ginger extract. Whether PDE inhibition in vivo can be achieved through ingestion of artichoke or ginger extracts leading to physiological effects concerning cardiovascular health should be addressed in future research.

Background: Roasted seeds of Amazonian guarana (Paullinia cupana var. sorbilis; Sapindaceae) are popular in South America due to their stimulant activity on the central nervous system (CNS). Rich in purine alkaloids, markedly caffeine, the seeds are extensively used in the Brazilian beverage industry for the preparation of soft drinks and as additives in energy drinks. Methods: To investigate the putative anti-aging and antioxidant activity of guarana, we used the model organism Caenorhabditis elegans. Chemical analyses were performed using high-performance liquid chromatography (HPLC) and electrospray ionization-mass spectrometry (ESI-MS/MS). Results: When tested in the model system Caenorhabditis elegans, the water extract from roasted guarana seeds enhanced resistance against oxidative stress, extended lifespan and attenuated aging markers such as muscle function decline and polyQ40 aggregation. Conclusions: In the current study, we demonstrate that guarana extracts can work as a powerful antioxidant in vivo; moreover, guarana extracts exhibit anti-aging properties. Our results suggest that the biological activities of guarana go beyond the extensively reported CNS stimulation.