Biomarkers of Berry Intake: Systematic Review Update

Berries are rich in (poly)phenols, and these compounds may be beneficial to human health. Estimating berry consumption through self-reported questionnaires has been challenging due to compliance issues and a lack of precision. Estimation via food-derived biomarkers in biofluids was proposed as a complementary alternative. We aimed to review and update the existing evidence on biomarkers of intake for six different types of berries. A systematic literature search was performed to update a previous systematic review on PubMed, Web of Science, and Scopus from January 2020 until December 2022. Out of 42 papers, only 18 studies were eligible. A multimetabolite panel is suggested for blueberry and cranberry intake. Proposed biomarkers for blueberries include hippuric acid and malvidin glycosides. For cranberries, suggested biomarkers are glycosides of peonidin and cyanidin together with sulfate and glucuronide conjugates of phenyl-γ-valerolactone derivatives. No new metabolite candidates have been found for raspberries, strawberries, blackcurrants, and blackberries. Further studies are encouraged to validate these multimetabolite panels for improving the estimation of berry consumption.

From waste to the gut: Can blackcurrant press cake be a new functional ingredient? Insights on in vivo microbiota modulation, oxidative stress, and inflammation

Blackcurrant press cake (BPC) is a source of anthocyanins, and this study evaluated the bioactivity and gut microbiota modulation of blackcurrant diets with or without 1,2 dimethylhydrazine (DMH)-induced colon carcinogenesis in rats. In colon cancer-induced rats (CRC), BPC at the highest dosages increased pro-inflammatory parameters and the expression of anti-apoptotic cytokines, accentuating colon cancer initiation by aberrant crypts and morphological changes. Fecal microbiome analysis showed that BPC altered the composition and function of the gut microbiome. This evidence suggests that high doses of BPC act as a pro-oxidant, accentuating the inflammatory environment and CRC progression.

The Effects of Blackcurrant and Raspberry Consumption on Blood Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

A systematic review and meta-analysis were designed to summarize studies conducted on the effects of raspberry and blackcurrant consumption on blood pressure (BP). Eligible studies were detected by searching numerous five online databases including PubMed, Scopus, Web of Science, Cochrane Library, and Google Scholar, until December 17, 2022. We pooled the mean difference and its 95% confidence interval (CI) by applying a random-effects model. Overall, the impact of raspberry and blackcurrant on BP was reported in ten randomized controlled trials (RCTs) (420 subjects). Pooled analysis of six clinical trials revealed that raspberry consumption has no significant reduction in systolic blood pressure (SBP) (weighted mean differences [WMDs], -1.42; 95% CI, -3.27 to 0.87; p = 0.224) and diastolic blood pressure (DBP) (WMD, -0.53; 95% CI, -1.77 to 0.71; p = 0.401), in comparison with placebo. Moreover, pooled analysis of four clinical trials indicated that blackcurrant consumption did not reduce SBP (WMD, -1.46; 95% CI, -6.62 to 3.7; p = 0.579), and DBP (WMD, -2.09; 95% CI, -4.38 to 0.20; p = 0.07). Raspberry and blackcurrant consumption elicited no significant reductions in BP. More accurate RCTs are required to clarify the impact of raspberry and blackcurrant intake on BP.

Study on the reduction of heterocyclic amines by marinated natural materials in pork belly

This study was conducted to determine the effect of natural ingredient seasoning on the reduction of heterocyclic amine (HCA) production that may occur when pork belly is cooked at a very high temperature for a long time. Pork belly seasoned with natural ingredients, such as natural spices, blackcurrant, and gochujang, was cooked using the most common cooking methods, such as boiling, pan fry, and barbecue. HCAs in pork belly were extracted through solid-phase extraction and analyzed via high-performance liquid chromatography. For short-term toxicity, a mouse model was used to analyze weight, feed intake, organ weight, and length; hematology and serology analysis were also performed. Results revealed that HCAs formed only when heating was performed at a very high temperature for a long time, not under general cooking conditions. Although the toxicity levels were not dangerous, the method showing the relatively highest toxicity among various cooking methods was barbecue, and the natural material with the highest toxicity reduction effect was blackcurrant. Furthermore, seasoning pork belly with natural materials containing a large amount of antioxidants, such as vitamin C, can reduce the production of toxic substances, such as HCAs, even if pork belly is heated to high temperatures.

The effect of biopolymer-water interaction on relaxation phenomena in blackcurrant pectin solutions

Pectin is commonly used food additive. Depends on the source of the acquisition, its properties may vary significantly, therefore pectin obtained from different sources may be used for various purposes. Little information can be found about the properties of blackcurrant pectin. Therefore, the aim of this study was to investigate blackcurrant pectin properties, with particular emphasis on biopolymer behaviour in aqueous solutions. Applied water extraction resulted in a water-soluble fraction of pectin with M_w = 115.75 kg·mol^-1. Aqueous solutions of obtained polysaccharides was tested with various methods (membrane osmometry, DLS, NMR, viscosity tests) that allowed for a comprehensive description of biopolymer-biopolymer and biopolymer-water interactions in both, dilute and semidilute regime. Blackcurrant pectin exhibits behaviour characteristic for polyelectrolytes. The analysis of the obtained results shows that, despite its low molecular weight, obtained pectin has a highly branched structure, which influences strong intermolecular interactions in solutions.

A comparison study between ultrasound-assisted and enzyme-assisted extraction of anthocyanins from blackcurrant (Ribes nigrum L.)

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2 anthocyanin extraction methods have been developed in blackcurrant by EAE and UAE.

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The 7 major anthocyanins have been separated in less than 7 min.

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The composition of the extraction solvent has been the most influential variable.

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Optimal extraction times have been 5 min for UAE and 10 min for EAE.

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No differences have been observed in anthocyanin extraction with both methods.

Blackcurrant (Ribes nigrum L.) is a fruit rich in vitamins, fatty acids, minerals, essential oils and phenolic compounds, including anthocyanins. In the present work, two anthocyanin extraction methods from blackcurrant samples based on Ultrasound-Assisted Extraction (UAE) and Enzyme-Assisted Extraction (EAE) have been developed. A Plackett–Burman design with seven variables has been preliminary used for both UAE and EAE in order to determine the most influential variables in each methodology. After that, a Box-Behnken design was employed to optimize the extraction methods. The composition of the extraction solvent (% EtOH in water) has been the most influential variable for both UAE and EAE. The optimal extraction times have been 5 min for UAE and 10 min for EAE. No differences have been observed in anthocyanin extraction with both methodologies. Both methods have been applied to blackcurrant-derived products and proven their suitability for quality control analysis.

Phenolic composition, antioxidant capacity and physical characterization of ten blackcurrant (Ribes nigrum) cultivars, their juices, and the inhibition of type 2 diabetes and inflammation biochemical markers

The objective was to analyze the phenolic composition, antioxidant capacity, and physical characteristics of 10 blackcurrant cultivars, their juices, and the enzymatic inhibition of dipeptidyl peptidase-IV, α-amylase, α-glucosidase, nitric oxide synthase, and cyclooxygenase-2. Fruit masses ranged from 0.47 to 1.22 g and diameters from 7.42 to 14.42 mm. For the juices, pH ranged from 2.80 to 2.96, soluble solids from 11.33% to 17.5%, total acidity from 3.17 to 4.26 g/100 mL, and viscosity from 1.28 to 273.83 mPa·s. Total anthocyanins (TA) ranged from 1.81 to 5.48 mg eq cyanidin 3-O-glucoside/100 g, total polyphenols (TP) from 7.67 to 39.70 mg eq gallic acid/100 g, total condensed tannins from 3.24 to 7.76 g eq catechin/100 g, and antioxidant capacity from 219.24 to 499.26 μmol eq Trolox/100 g. Juices of the cultivars Coronet and Consort contained the highest levels of TA, TP, and antioxidants. Whistler cultivar contained high concentrations of major anthocyanins. Juices from all cultivars favorably inhibited the activities of enzymes used as surrogate biochemical markers for T2 diabetes and inflammation.

Combination of rehydrated whey protein isolate aqueous solution with blackcurrant concentrate and the formation of encapsulates via spray-drying and freeze-drying: Alterations to the functional properties of protein and their anticancer properties

Novel protein ingredients were produced by encapsulating blackcurrant concentrate (BC) with whey protein through spray-, or freeze-, drying strategies. The effects of encapsulation strategies and the addition of BC on the physical and functional characteristics, and anticancer activity of the ingredients were evaluated. The mechanistic interactions between the blackcurrant anthocyanins (BAs) with the whey protein components were predicted via in silico studies. HPLC results revealed that spray-dried and freeze-dried whey protein-BC encapsulates have effectively delivered the BAs. The physical and functional properties of the proteins were altered by drying strategies and the addition of BC. Anticancer effects were linked to reactive oxygen species production and cell apoptosis towards HepG2. Molecular docking results showed that hydrogen bonds were the main binding forces between BAs and various whey protein molecules, resulting in the formation of complexes. These findings are relevant to the formulation of powdered products to be used as ingredients in practical food matrix.

Food intake biomarkers for berries and grapes

Grapes and berries are two types of widely consumed fruits characterized by a high content in different phytochemicals. However, their accurate dietary assessment is particularly arduous, because of the already wide recognized bias associated with self-reporting methods, combined with the large range of species and cultivars and the fact that these fruits are popularly consumed not only in fresh and frozen forms but also as processed and derived products, including dried and canned fruits, beverages, jams, and jellies. Reporting precise type and/or quantity of grape and berries in FFQ or diaries can obviously be affected by errors. Recently, biomarkers of food intake (BFIs) rose as a promising tool to provide accurate information indicating consumption of certain food items. Protocols for performing systematic reviews in this field, as well as for assessing the validity of candidate BFIs have been developed within the Food Biomarker Alliance (FoodBAll) Project. This paper aims to evaluate the putative BIFs for blueberries, strawberries, raspberries, blackberries, cranberries, blackcurrant, and grapes. Candidate BFIs for grapes were resveratrol metabolites and tartaric acid. The metabolites considered as putative BFI for berries consumption were mostly anthocyanins derivatives together with several metabolites of ellagitannins and some aroma compounds. However, identification of BFIs for single berry types encountered more difficulties. In the absence of highly specific metabolites reported to date, we suggested some multi-metabolite panels that may be further investigated as putative biomarkers for some berry fruits.

Quantitative trait loci mapping of polyphenol metabolites in blackcurrant (Ribes nigrum L.)

INTRODUCTION

Commercially, blackcurrants (Ribes nigrum L.) are grown mainly for processing, especially for juice production. They are valued for their high levels of polyphenols, especially anthocyanins, which contribute to their characteristic deep colour, but also as a good source of vitamin C. Recently, evidence has accrued that polyphenols, such as anthocyanins, may have specific human health benefits.

OBJECTIVE

The aims of this study were to investigate the genetic control of polyphenols and other key juice processing traits in blackcurrants.

METHODS

The levels, over 2 years, of vitamin C, citrate, malate, succinate, total organic acids, total anthocyanins and total phenolics together with 46 mainly polyphenol metabolites were measured in a blackcurrant biparental mapping population. Quantitative trait loci (QTLs) for these traits were mapped onto a high-density SNP linkage map.

RESULTS

At least one QTL was detected for each trait, with good consistency between the 2 years. Clusters of QTLs were found on each of the eight linkage groups (LG). For example, QTLs for the major anthocyanidin glucosides, delphinidin-3-O-glucoside and cyanidin-3-O-glucoside, co-localised with a QTL for total anthocyanin content on LG3 whereas the major anthocyanidin rutinosides, delphinidin-3-O-rutinoside and cyanidin-3-O-rutinoside, had QTLs on LG1 and LG2. Many of the QTLs explained a high proportion of the trait variation, with the most significant region, on LG3 at ~ 35 cM, explaining more than 60% of the variation in the coumaroylated metabolites, Cyanidin-coumaroyl-glucose, Delphinidin-coumaroyl-glucose, Kaempferol-coumaroyl-glucose and Myricetin-coumaroyl-glucose.

CONCLUSION

The identification of robust QTLs for key polyphenol classes and individual polyphenols in blackcurrant provides great potential for marker-assisted breeding for improved levels of key components.

Application of HPLC-PDA-MS metabolite profiling to investigate the effect of growth temperature and day length on blackcurrant fruit

INTRODUCTION

Blackcurrant (Ribes nigrum L.) is an excellent example of a "super fruit" with potential health benefits. Both genotype and cultivation environment are known to affect the chemical composition of blackcurrant, especially ascorbic acid and various phenolic compounds. Environmental conditions, like temperature, solar radiation and precipitation can also have significant impact on fruit chemical composition. The relevance of the study is further accentuated by the predicted and ongoing changes in global climate.

OBJECTIVES

The aim of the present study was to provide new knowledge and a deeper understanding of the effects of post flowering environmental conditions, namely temperature and day length, on fruit quality and chemical composition of blackcurrant using an untargeted high performance liquid chromatography-photo diode array-mass spectrometry (HPLC-PDA-MS) metabolomics approach.

METHODS

A phytotron experiment with cultivation of single-stemmed potted plants of blackcurrant cv. Narve Viking was conducted using constant temperatures of 12, 18 or 24 °C and three different photoperiods (short day, short day with night interruption, and natural summer daylight conditions). Plants were also grown under ambient outdoor conditions. Ripe berries were analysed using an untargeted HPLC-PDA-MS metabolomics approach to detect the presence and concentration of molecules as affected by controlled climatic factors.

RESULTS

The untargeted metabolomics dataset contained a total of 7274 deconvolved retention time-m/z pairs across both electrospray ionisation (ESI) positive and negative polarities, from which 549 metabolites were identified or minimally annotated based upon accurate mass MS. Conventional principal component analysis (PCA) in combination with the Friedman significance test were applied to first identify which metabolites responded to temperature in a linear fashion. Multi-block hierarchical PCA in combination with the Friedman significance test was secondly applied to identify metabolites that were responsive to different day length conditions. Temperature had significant effect on a total of 365 metabolites representing a diverse range of chemical classes. It was observed that ripening of the blackcurrant berries under ambient conditions, compared to controlled conditions, resulted in an increased accumulation of 34 annotated metabolites, mainly anthocyanins and flavonoids. 18 metabolites were found to be regulated differentially under the different daylength conditions. Moreover, based upon the most abundant anthocyanins, a comparison between targeted and untargeted analyses, revealed a close convergence of the two analytical methods. Therefore, the study not just illustrates the value of non-targeted metabolomics approaches with respect to the huge diversity and numbers of significantly changed metabolites detected (and which would be missed by conventional targeted analyses), but also shows the validity of the non-targeted approach with respect to its precision compared to targeted analyses.

CONCLUSIONS

Blackcurrant maturation under controlled ambient conditions revealed a number of insightful relationships between environment and chemical composition of the fruit. A prominent reduction of the most abundant anthocyanins under the highest temperature treatments indicated that blackcurrant berries in general may accumulate lower total anthocyanins in years with extreme hot summer conditions. HPLC-PDA-MS metabolomics is an excellent method for broad analysis of chemical composition of berries rich in phenolic compounds. Moreover, the experiment in controlled phytotron conditions provided additional knowledge concerning plant interactions with the environment.

Enzymatic acylation of blackcurrant (Ribes nigrum) anthocyanins and evaluation of lipophilic properties and antioxidant capacity of derivatives

Anthocyanin-rich fractions isolated from blackcurrant (Ribes nigrum L.) including delphinidin-3-O-glucoside, delphinidin-3-O-rutinoside, cyanidin-3-O-glucoside and cyanidin-3-O-rutinoside were enzymatically acylated with lauric acid. All the four anthocyanins were successfully monoacylated, and their relative proportions did not affect the conversion yield. The acylation occurred at the 6″-OH position of the glucosides and at the rhamnose 4‴-OH of the rutinosides. The rutinoside moieties of the anthocyanins were successfully acylated for the first time, and the corresponding acylation sites were verified by NMR analysis. The acylation enhanced the lipophilicity. The hydrophilic anthocyanin rutinosides were more lipophilic after acylation. Introducing lauric acid into the anthocyanins significantly improved the thermostability and capacity to inhibit lipid peroxidation and maintained UV-vis absorbance and antioxidant activity. This research provides important insights into acylation of mixed anthocyanins with different glycosyl moieties.

Colour bio-factories: Towards scale-up production of anthocyanins in plant cell cultures

Anthocyanins are widely distributed, glycosylated, water-soluble plant pigments, which give many fruits and flowers their red, purple or blue colouration. Their beneficial effects in a dietary context have encouraged increasing use of anthocyanins as natural colourants in the food and cosmetic industries. However, the limited availability and diversity of anthocyanins commercially have initiated searches for alternative sources of these natural colourants. In plants, high-level production of secondary metabolites, such as anthocyanins, can be achieved by engineering of regulatory genes as well as genes encoding biosynthetic enzymes. We have used tobacco lines which constitutively produce high levels of cyanidin 3-O-rutinoside, delphinidin 3-O-rutinoside or a novel anthocyanin, acylated cyanidin 3-O-(coumaroyl) rutinoside to generate cell suspension cultures. The cell lines are stable in their production rates and superior to conventional plant cell cultures. Scale-up of anthocyanin production in small scale fermenters has been demonstrated. The cell cultures have also proven to be a suitable system for production of 13C-labelled anthocyanins. Our method for anthocyanin production is transferable to other plant species, such as Arabidopsis thaliana, demonstrating the potential of this approach for making a wide range of highly-decorated anthocyanins. The tobacco cell cultures represent a customisable and sustainable alternative to conventional anthocyanin production platforms and have considerable potential for use in industrial and medical applications of anthocyanins.

Probiotic fruit beverages with different polyphenol profiles attenuated early insulin response

BACKGROUND

Consumption of polyphenol-rich fruits and vegetables may improve postprandial glucose and insulin levels and hence promote well-being. Previously it has been observed that consumption of bilberry decreases the postprandial insulin demand. The intention with the present study was to compare the impact of different supplements with various polyphenol profiles, on the postprandial glucose and insulin responses in healthy young adults.

METHODS

In a randomized, controlled, crossover study the postprandial glycemic and insulin responses were observed in eleven healthy adults after intake of five different beverages containing bilberry (European blueberry), blackcurrant, beetroot, mango and rose hip, respectively; all drinks were enriched with the same composition of fermented oatmeal and probiotics. The control was a glucose drink. The profile and content of the polyphenols in the different beverages were determined by HPLC-DAD analysis. The antioxidative capacity of the different beverages were measured by TEAC and DPPH assays.

RESULTS

Beverages containing bilberry, blackcurrant, mango or rose hip significantly attenuated the early postprandial insulin response (0-90 min), but showed no effect on glucose response. Drinks with bilberry or rose hip reduced the insulin response from the very early phase (0-30 min), and had significantly lower insulin index compared with the control. The efficiency of the bilberry and rose hip to decrease early postprandial insulin responses correlated with higher phenolic contents.

CONCLUSIONS

Supplements with bilberry, blackcurrant, mango or rose hip in the tested probiotic and oatmeal enriched beverage attenuated early-phase insulin response, but had no effect on the postprandial glycemic response. The improved ability of bilberry and rose hip to lower the very early phase of insulin response seems to be due to a higher phenolic content.

TRIAL REGISTRATION

The study was retrospectively registered at ClinicalTrials.gov with number NCT03159065 .

The potency of commercial blackcurrant juices to induce relaxation in porcine coronary artery rings is not correlated to their antioxidant capacity but to their anthocyanin content

OBJECTIVE

Polyphenol-rich products such as fruit juices have been found to have strong antioxidant capacities and to induce potent endothelium-dependent relaxation. We evaluated whether the commercial blackcurrant juices induced endothelium-dependent relaxation of isolated coronary arteries can be related to their antioxidant capacity and/or phenolic content.

METHODS

Six different commercial blackcurrant juices were selected. Their main phenolic compounds were measured by ultra-performance liquid chromatography and antioxidant capacity was evaluated by spectrometric methods. Vascular reactivity studies with these juices were done using isolated porcine coronary arteries.

RESULTS

The six different commercial blackcurrant juices induced relaxation ranging from 21% to 100% at the concentration of 0.5% volume per volume (v/v). The relaxation induced at 0.5% v/v was not correlated to their antioxidant capacity measured by either oxygen radical antioxidant capacity or DPPH (2,2-diphenyl-1-picrylhydrazyl) assays and also not to the ascorbic acid, total polyphenols, total flavanols, and total phenolic acid contents. In contrast, the amplitude of the relaxation was correlated to the total anthocyanins content and the individual anthocyanin concentration.

CONCLUSIONS

Correlations between relaxation amplitude and total anthocyanin or individual anthocyanin contents are of interest for the development of functional blackcurrant beverages with the potential to promote vascular protection.

Antispasmodic Effect of Blackcurrant (Ribes nigrum L.) Juice and Its Potential Use as Functional Food in Gastrointestinal Disorders

OBJECTIVE

The purpose of this study was to investigate the relaxative effects of blackcurrant juice on the gastrointestinal smooth muscle in vitro.

MATERIALS AND METHODS

Berries of the blackcurrant cultivar Ometa were used for the preparation of the juice used. The spasmolytic activity of blackcurrant juice was tested on rat ileum isolated from male Wistar rats by monitoring its influence on spontaneous contractions, as well as contractions induced by potassium chloride (KCl), barium chloride (BaCl2), calcium chloride (CaCl2), and acetylcholine (Ach). The results are expressed as the mean ± standard deviation obtained in 6 measurements and statistical significance was determined by the Student t test, with p < 0.05 taken as significant.

RESULTS

The blackcurrant cultivar Ometa significantly reduced the frequency and the amplitude of spontaneous contractions (57.94 ± 3.44%) and Ach-induced contractions (42.74 ± 5.36%; p < 0.05) of the isolated rat ileum. Cumulative concentrations (0.01-3 mg/mL) of the Ometa juice also reduced contractions of the isolated rat ileum stimulated by KCl (51.46 ± 6.87%), CaCl2 (57.54 ± 6.47%), and BaCl2 (58.54 ± 10.55%). The inhibitory effects of the juice were proportional to the applied concentration.

CONCLUSION

The antispasmodic effect of Ometa cultivar shows that common gastrointestinal disorders could be treated by the functional food.

Distribution of apple and blackcurrant microbiota in Lithuania and the Czech Republic

The microbial assemblies on the surface of plants correlate with specific climatic features, suggesting a direct link between environmental conditions and microbial inhabitation patterns. At the same time however, microbial communities demonstrate distinct profiles depending on the plant species and region of origin. In this study, we report Next Generation Sequencing-based metagenomic analysis of microbial communities associated with apple and blackcurrant fruits harvested from Lithuania and the Czech Republic. Differences in the taxonomic composition of eukaryotic and prokaryotic microorganisms were observed between plant types. Our results revealed limited geographic differentiation between the bacterial and fungal communities associated with apples. In contrast, blackcurrant berries harvested from different regions demonstrated high diversity in both bacterial and fungal microbiota structures. Among fungal and bacterial microorganisms, we identified both potentially beneficial (Cryptococcus, Hanseniaspora, Massilia, Rhodotorula, Sphingomonas) and phytopathogenic microorganisms (Cladosporium, Pantoea, Phoma, Pseudomonas, Septoria, Taphrina) indicating their important roles in ecological and evolutionary processes.

Blackcurrant anthocyanins stimulated cholesterol transport via post-transcriptional induction of LDL receptor in Caco-2 cells

PURPOSES

We previously showed that polyphenol-rich blackcurrant extract (BCE) showed a hypocholesterolemic effect in mice fed a high fat diet. As direct cholesterol removal from the body via the intestine has been recently appreciated, we investigated the effect of BCE on the modulation of genes involved in intestinal cholesterol transport using Caco-2 cells as an in vitro model.

METHODS

Caco-2 cells were treated with BCE to determine its effects on mRNA and protein expression of genes important for intestinal cholesterol transport, low-density lipoprotein (LDL) uptake, cellular cholesterol content, and cholesterol transport from basolateral to apical membrane of Caco-2 cell monolayers. Cells were also treated with anthocyanin-rich or -poor fraction of BCE to determine the role of anthocyanin on BCE effects.

RESULTS

BCE significantly increased protein levels of LDL receptor (LDLR) without altering its mRNA, which consequently increased LDL uptake into Caco-2 cells. This post-transcriptional induction of LDLR by BCE was markedly attenuated in the presence of rapamycin, an inhibitor of mechanistic target of rapamycin complex 1 (mTORC1). In addition, BCE altered genes involved in cholesterol transport in the enterocytes, including apical and basolateral cholesterol transporters, in such a way that could enhance cholesterol flux from the basolateral to apical side of the enterocytes. Indeed, BCE significantly increased the flux of LDL-derived cholesterol from the basolateral to the apical chamber of Caco-2 monolayer. LDLR protein levels were markedly increased by anthocyanin-rich fraction, but not by anthocyanin-free fraction.

CONCLUSION

mTORC1-dependent post-transcriptional induction of LDLR by BCE anthocyanins drove the transport of LDL-derived cholesterol to the apical side of the enterocytes. This may represent a potential mechanism for the hypocholesterolemic effect of BCE.

Blackcurrant anthocyanins modulate CCL11 secretion and suppress allergic airway inflammation

CCL11, a chemokine, is linked to the early development of airways eosinophilia in allergic asthma. Therefore, CCL11 production is a target for abrogating eosinophilic-driven airway inflammation. Blackcurrants are high in compounds that regulate inflammation, particularly anthocyanins. In this study, we investigated the effect of oral blackcurrant supplementation on allergen-induced eosinophilia and CCL11 production; we also profiled key compounds in blackcurrants that were linked to this effect. Ten milligram per kilogram (total anthocyanins) of a commercially available, anthocyanin-rich New Zealand "Ben Ard" blackcurrant extract ("Currantex 30") attenuated ovalbumin-induced inflammation, eosinophilia (by 52.45 ± 38.50%), and CCL11 production (by 48.55 ± 28.56%) in a mouse model of acute allergic lung inflammation. Ten blackcurrant polyphenolic extracts were also found to suppress CCL11 secretion by stimulated human lung epithelial cells in vitro. Correlation analysis identified potential blackcurrant polyphenolic anthocyanin constituents specifically delphinidins and cyanidins, involved in CCL11 suppression. Our findings show oral supplementation with New Zealand blackcurrant is effective in reducing lung inflammation, and highlight the potential benefit of developing cultivars with specific polyphenolic profiles for the creation of functional foods with desirable biological activity.

Changing the content of phenolic compounds as the response of blackcurrant (Ribes nigrum L.) leaves after blackcurrant leaf midge (Dasineura tetensi Rübs.) infestation

Blackcurrant leaf midge (Dasineura tetensi) is one of the most common pests of blackcurrant (Ribes nigrum). The aim of this study was to investigate changes in the content of phenolic compounds in the leaves damaged by the larvae of this pest. Additionally, susceptibility of different blackcurrant cultivars to the midge attack was investigated. Qualitative and quantitative analyses of control and pest-infested blackcurrant leaves were performed using LC-PDA-QTOF/MS and UPLC-PDA-FL systems. A total of 39 types of phenolic compounds were identified in blackcurrant leaf extracts and they included 3 flavan-3-ols, 14 hydroxycinnamic acid derivatives, and 22 flavonols. Feeding of blackcurrant leaf midge on blackcurrant leaves lowered the content of leaf polyphenolic compounds. The greatest differences in polyphenolics between control and infected leaves were observed in 'Ruben', 'Fariegh', 'Foxendown', 'Ores', 'Ben Hope', 'Ben Connan' and 'Tisel' cultivars that were probably highly susceptible to the pest attack. In the other cultivars: 'Ben Finlay', 'Polares', 'Tiben', and 'Gofert' the differences in phenolics content were less pronounced, so they were probably less susceptible to D. tetensi attack. Plant polyphenolic compounds was strongly involved in pathogen-plant interaction, and their accumulation significantly decreased as a result of the pathogen attack.

Phytoestrogenic activity of blackcurrant (Ribes nigrum) anthocyanins is mediated through estrogen receptor alpha

SCOPE

Blackcurrants (Ribes nigrum L., Grossulariaceae) contain high amounts of anthocyanin polyphenols, which have antioxidant and anti-carcinogenic health benefits. This study analyzed the potential phytoestrogenic effects of blackcurrant extract (BCE) in breast cancer (MCF-7) and human endometrial cancer (Ishikawa) cell lines that over-express estrogen receptor alpha (ERα), as well as in immature female rats.

METHODS AND RESULTS

Microarray analysis and Ingenuity® Pathway Analysis showed that BCE activated the ERα pathway, whereas quantitative-PCR confirmed that BCE and four types of anthocyanins up-regulated genes downstream of ERα. BCE (0.1-1.0 μg/mL) and anthocyanins (0.1-10 μM) induced MCF-7 cell proliferation; however, this effect was blocked by ER antagonist fulvestrant. Flow cytometry showed that anthocyanins reduced and increased the number of MCF-7 cells in the G0/G1 and G2/M phases, respectively. Anthocyanins stimulated ERα transcriptional activity in human ERα reporter assays and induced alkaline phosphatase activity in Ishikawa cells. Competition assays and in silico analysis indicated that anthocyanins bind to ERα. Finally, BCE focally induced stratification of columnar epithelial cells in the rat uterus and increased cytoplasmic mucin levels in these cells.

CONCLUSION

These results suggest that blackcurrant anthocyanins act as phytoestrogens in vitro and in vivo.

Polyphenol-rich blackcurrant extract prevents inflammation in diet-induced obese mice

Obesity is closely associated with chronic, low-grade inflammation. We investigated if polyphenol-rich blackcurrant extract (BCE) can prevent inflammation in vivo. Male C57BL/6J mice were fed a modified AIN-93M control diet containing high fat/high cholesterol (16% fat, 0.25% cholesterol by weight) or the control diet supplemented with 0.1% BCE (wt/wt) for 12 weeks. In BCE-fed mice, the percentage of body weight and adipocyte size of the epididymal fat were significantly lower than those of control mice. There were fewer crown-like structures (CLS) with concomitant decreases in F4/80, cluster of differentiation 68 and inhibitor of nuclear factor κB kinase ε (IKKε) mRNA in the epididymal adipose of BCE-fed mice. F4/80 and IKKε mRNA levels were positively correlated with CLS number. In the skeletal muscle of mice fed with BCE, mRNA expression of genes involved in energy expenditure and mitochondrial biogenesis, including PPARα, PPARδ, UCP-2, UCP-3 and mitochondrial transcription factor A, were significantly increased. When splenocytes from BCE-fed mice were stimulated by lipopolysaccharides, tumor necrosis factor α and interleukin-1β mRNA were significantly lower than control splenocytes. Together, the results suggest that BCE supplementation decreases obesity-induced inflammation in adipose tissue and splenocytes, at least in part, by modulating energy metabolism in skeletal muscle.