Polyphenolic profiles and antioxidant and antiradical activity of Italian berries from Vaccinium myrtillus L. and Vaccinium uliginosum L. subsp. gaultherioides (Bigelow) S.B. Young

Vaccinium uliginosum L. (bog bilberry) and the search for its alleged toxicity: a review

Bog bilberry (Vaccinium uliginosum L.) is a wild-growing berry native to all circumboreal regions. There is however a significant discrepancy in the uses of bog bilberry fruits around the world. There exists a strong prejudice against the use of these berries in many European countries as well as a few incidences of poisoning reported between 1906 and 1944. In Asia and North America, this fear is completely absent from the local knowledge and the bog bilberry is valued as an excellent food and medicinal plant. There has been a lack of research on the topic in the last 50 years and thus the presumed toxicity remains unproven. This review aims to gather the conflicting information from all regions where bog bilberry grows and present them in a critical way to elucidate the possible explanations for the discrepancies. There are several possible explanations for the alleged toxicity of the bog bilberry, including a fungal infection of the fruits, individual intolerance or accidental poisoning by a different plant species; the local names meaning "drunk, inebriating, vomit-inducing berry" may be related to the alcoholic drinks made from them. This review highlights the gap in knowledge and serves as a theoretical framework for future research.

Src Tyrosine Kinase Inhibitory and Antioxidant Activity of Black Chokeberry and Bilberry Fruit Extracts Rich in Chlorogenic Acid

Edible berries such as the fruits of black chokeberry (Aronia melanocarpa (Michx.) Elliott) and bilberry (Vaccinium myrtillus L.) are considered to be rich in phenolic compounds, which are nowadays attracting great interest due to their promising health benefits. The main objective of our study was to investigate, for the first time, their inhibitory properties on Src tyrosine kinase activity, as this enzyme plays an important role in multiple cellular processes and is activated in both cancer and inflammatory cells. In hydroethanolic fruit extracts, 5.0-5.9% of total polyphenols were determined spectrophotometrically, including high amounts of hydroxycinnamic acid derivatives. HPLC analysis revealed that the black chokeberry and bilberry extracts contained 2.05 mg/g and 2.54 mg/g of chlorogenic acid, respectively. Using a time-resolved fluorescence resonance energy transfer (TR-FRET) assay, the extracts studied were found to have comparable inhibitory effects on Src tyrosine kinase, with IC50 values of 366 µg/mL and 369 µg/mL, respectively. The results also indicated that chlorogenic acid contributes significantly to the observed effect. In addition, both fruit extracts exhibited antioxidant activity by scavenging DPPH and NO radicals with SC50 values of 153-352 µg/mL. Our study suggested that black chokeberry and bilberry fruits may be beneficial in cancer and other inflammation-related diseases.

Vaccinium uliginosum and Vaccinium myrtillus-Two Species-One Used as a Functional Food

Vaccinium uliginosum L. (commonly known as bog bilberry) and Vaccinium myrtillus L. (commonly known as bilberry) are species of the genus Vaccinium (family Ericaceae). The red-purple-blue coloration of blueberries is attributed largely to the anthocyanins found in bilberries. Anthocyanins, known for their potent biological activity as antioxidants, have a significant involvement in the prophylaxis of cancer or other diseases, including those of metabolic origin. Bilberry is the most important economically wild berry in Northern Europe, and it is also extensively used in juice and food production. A review of the latest literature was performed to assess the composition and biological activity of V. uliginosum and V. myrtillus. Clinical studies confirm the benefits of V. uliginosum and V. myrtillus supplementation as part of a healthy diet. Because of their antioxidant, anti-inflammatory, anti-cancer, and apoptosis-reducing activity, both bog bilberries and bilberries can be used interchangeably as a dietary supplement with anti-free radical actions in the prevention of cancer diseases and cataracts, or as a component of sunscreen preparations.

Wild sweet cherry, strawberry and bilberry as underestimated sources of natural colorants and bioactive compounds with functional properties

Wild edible fruits, neglected by the development of commercial agriculture, have recently aroused as a good source of natural colorants and bioactive compounds. These novel uses could cover the recent demand for healthier foods with functional properties. Prunus avium, Fragaria vesca and Vaccinium myrtillus wild fruits were characterized by individual anthocyanin profile and color CIELAB parameters, as well as phenolic fraction. In addition, some bioactivities were evaluated. In P. avium cyanidin-O-deoxyhexosyl-pentoside was the representative anthocyanin, in F. vesca pelargonidin-3-O-glucoside and in V. myrtillus delphinidin-O-hexoside. The three wild edible fruits showed interesting antioxidant activity especially in OxHLIA assays. V. myrtillus was the fruit with the best results for the bacterial growth inhibition, while F. vesca with better fungal growth inhibition. These results evidenced the richness of these wild fruits in bioactive compounds and pigments with antioxidant capacity, therefore, their potential use as natural colorants for healthier food products design.

Oxidative Stress and Natural Antioxidants in Osteoporosis: Novel Preventive and Therapeutic Approaches

This review reports in detail the cellular and molecular mechanisms which regulate the bone remodeling process in relation to oxidative stress (OS), inflammatory factors, and estrogen deficiency. OS is considered an important pathogenic factor of osteoporosis, inducing osteocyte apoptosis and varying levels of specific factors, such as receptor activator κB ligand (RANKL), sclerostin, and, according to recent evidence, fibroblast growth factor 23, with consequent impairment of bone remodeling and high bone resorption. Bone loss increases the risk of fragility fractures, and the most commonly used treatments are antiresorptive drugs, followed by anabolic drugs or those with a double effect. In addition, recent data show that natural antioxidants contained in the diet are efficient in preventing and reducing the negative effects of OS on bone remodeling and osteocytes through the involvement of sirtuin type 1 enzyme. Indeed, osteocytes and some of their molecular factors are considered potential biological targets on which antioxidants can act to prevent and reduce bone loss, as well as to promote bone anabolic and regenerative processes by restoring physiological bone remodeling. Several data suggest including antioxidants in novel therapeutic approaches to develop better management strategies for the prevention and treatment of osteoporosis and OS-related bone diseases. In particular, anthocyanins, as well as resveratrol, lycopene, oleuropein, some vitamins, and thiol antioxidants, could have protective and therapeutic anti-osteoporotic effects.

Quality by Design in optimizing the extraction of (poly)phenolic compounds from Vaccinium myrtillus berries

Quality by Design was adopted for developing an effective extraction procedure of (poly)phenolic compounds from bilberry (Vaccinium myrtillus L.) fruits, using a pooled sample of berries from different regions of Ukraine. Mechanical solvent extraction, microwave-assisted extraction (MAE) and ultrasonic-assisted extraction (UAE) were investigated by screening matrices. Extraction time (Time, from 5 to 15 min), organic solvent type (OS type, methanol, ethanol and acetone), organic solvent percentage (OS%, from 50% to 90%), sample/extractant ratio (S/E ratio, from 0.025 to 0.1 g mL^-1), and, only for MAE, extraction temperature (T, from 30 to 60°C), were selected as critical method parameters (CMPs). The spectrophotometric assays total soluble polyphenols (TSP), total monomeric anthocyanins (TMA), and radical scavenging activity (evaluated by the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), the 2,2'-azino-di-(3-ethylbenzthiazoline sulfonic acid), and the ferric reducing antioxidant power methods) were chosen as critical method attributes (CMAs). The screening procedure allowed for selecting UAE and methanol, while the other CMPs underwent further optimization through Response Surface Methodology. Target values for TSP, TMA and DPPH were selected and the method operable design region (MODR) was defined by means of Monte-Carlo simulations. The optimized conditions, with the corresponding MODR intervals in bracket, were the following: (i) Time, 17 min (15-23 min); OS%, 56% (44-59%); S/E ratio, 0.030 (0.022-0.034) g mL^-1. Under these experimental conditions, CMAs values of the pooled sample were the following (n = 3): TSP=4433±176 mg (+)-catechin eq/100 g dry weight (d.w.); TMA=3575±194 mg cyanidin-3-glucoside eq/100 g d.w.; DPPH=273±5 μg DPPH inhib./mg d.w. The optimized extraction method was tested for matrix effect (ME%) in the UHPLC-MS/MS analysis of 15 anthocyanins and 20 non-anthocyanins individual (poly)phenols commonly found in bilberries, as well as for luteolin, sinapic acid, and pelargonidin-3-glucoside, absent in this fruit and therefore added to the extracts as surrogate standards for evaluating apparent recovery (AR%). |ME%| was in any case ≤ 23% and AR% of the surrogate standards in the range 91-95%, confirming the very good performances of the optimized extraction method.

Geographic Variability of Berry Phytochemicals with Antioxidant and Antimicrobial Properties

The aim of this study was to determine the variability of several chemical compounds and the antioxidant and antimicrobial activities of eight types of berries harvested from two different geographical regions in the same year. The analyses were performed on bilberry, black currant, gooseberry, red currant, raspberry, sea buckthorn, strawberry and sour cherry, which were handpicked during the summer of 2019, in the same periods when they are typically harvested for consumer purposes. Total anthocyanins content (TAC), total flavonoids content (TFC), total polyphenolic compounds (TPC), determination of the Ferric-Reducing Antioxidant Power (FRAP), determination of the DPPH free radical scavenging assay (RSA), determination of nine phenolic compounds by HPLC-UV assay and antimicrobial activity were determined for undiluted hydroalcoholic extracts of all the studied berries. The results showed that the berries from Romania were richer in antioxidant compounds than the berries from Russia. The TPC content varied between 4.13-22.2 mg GAE/g d.w., TFC between 3.33-8.87 mg QE/g d.w. and TAC between 0.13-3.94 mg/g d.w. The highest variability was determined for TPC. Regarding the antioxidant activity assessed by FRAP assay, values were between 6.02-57.23 µmols TE/g d.w. and values for the RSA method between 18.44-83.81%. From the eight types of berries analyzed, bilberries and raspberries had the highest antioxidant activity considering both regions and both determination methods. Not only the type, but also the environmental and cultivation conditions in which the berries grow, can lead to variations in their chemical composition. The extracted polyphenolic compounds from the studied berries showed antibacterial properties on pathogens, such as Escherichia coli, Bacillus subtilis and Staphyloccocus aureus. The inhibitory action on Salmonella typhi and fungi Candida albicans and Aspegillus niger was absent to very low. The antimicrobial activity of the hydroalcoholic extracts was dependent on the provenance of the berries, too.

Bilberries: Curative and Miraculous – A Review on Bioactive Constituents and Clinical Research

Bilberry (Vaccinium myrtillus L.) fruits are an important part of local diets in many countries and are used as a medicinal herb to treat various disorders. Extracts from fruits are often a part of eye health-promoting supplements, whereas extracts from leaves are advertised for type 2 diabetes mellitus and glycemic control. This review provides an overview of the current knowledge of the phytochemical contents of bilberry fruits and leaves and their bioactivities, critically summarizes origins of the health claims and the outcome of clinical trials, with special attention towards those published in the past 10 years. Overall, the three most referenced indications, which are type 2 diabetes mellitus, vision disorders and circulatory diseases, all include contradictory results with no clear conclusion as to the benefits and recommended dosages. Moreover, the indications for vision disorders and diabetes originate from unproven or false claims that have been repeated in research since the 20th century without consistent fact-checking. Beneficial clinical results have been attested for the treatment of dyslipidemia and chronic inflammatory disorders when applied as dietary supplementation of fresh bilberries or as anthocyanin-rich bilberry fruit extracts. However, there is a general lack of double-blinded controlled research with larger sample sizes.

Electrochemical sensors based on sewage sludge-derived biochar for the analysis of anthocyanins in berry fruits

The reutilization of waste and the reduction of the general environmental impact of every production are fundamental goals that must be achieved in the framework of a circular economy. Recycled carbon-rich materials may represent a promising alternative to other less-sustainable carbonaceous materials used in the production of electrochemical sensing platforms. Herein, we propose an innovative carbon paste electrode (CPE) composed of biochar derived from biological sludge obtained from municipal and industrial wastewater treatment plants. The physicochemical properties of the biochar after a chemical treatment with an acidic solution obtained from industrial by-products were investigated. The electrode surface characterization was carried out by analyzing common redox probes and multiple phenols bearing varying numbers of –OH and –OCH₃ groups in their structure. Furthermore, the CPE was also tested on the evaluation of the phenolic fingerprints of Vaccinium myrtillus, Vaccinium uliginosum subsp. gaultherioides, and Fragaria × ananassa. Standard anthocyanin mixtures and extracts of the aforementioned fruits were analyzed to provide a phenolic characterization of real samples. The obtained results show that the sewage sludge–derived biochar can be a promising material for the development of electroanalytical sensors.

Protective Effect of Ribes nigrum Extract against Blue Light-Induced Retinal Degeneration In Vitro and In Vivo

Although blackcurrant has several health benefits, such as antioxidant and anti-inflammatory properties, its effects on the retina remain unclear. In this study, we investigated the efficacy of black currant extract (BCE) in an in vitro and in vivo model of dry age-related macular degeneration (AMD) induced by blue light. Dry macular degeneration is characterized by the abnormal accumulation of lipofuscin (e.g., N-retinylidene-N-retinylethanolamine, A2E) in the retina. Blue light (BL) significantly decreased the viability of A2E-laden human retinal pigment epithelial cells (ARPE-19). However, BCE treatment protected ARPE-19 cells from A2E and BL. A2E, which is oxidized by blue light, generates reactive oxygen species in RPE cells. Treatment with BCE significantly decreased (80.8%) reactive oxygen species levels induced by A2E and BL in a concentration-dependent manner. BCE inhibited A2E accumulation in ARPE-19 cells and significantly downregulated the expression of genes increased by A2E and BL in ARPE-19 cells. In vivo, oral administration of BCE (25–100 mg/kg) ameliorated ocular lesions of BL-induced retinal damage in a mouse model and rescued the thickness of the whole retina, photoreceptor segment layer, outer nuclear layer, and inner nuclear layer. The decrease in the number of nuclei in the outer nuclear layer induced by BL was also rescued by BCE. Additionally, BCE administration rescued (40.0%) the BL-induced reduction in the expression level of superoxide dismutase 1. Taken together, our results suggest that BCE may have preventive and therapeutic effects on dry AMD through its antioxidant activity and inhibition of lipofuscin accumulation in the retina.

Comparison of chemometric strategies for potential exposure marker discovery and false-positive reduction in untargeted metabolomics: application to the serum analysis by LC-HRMS after intake of Vaccinium fruit supplements

Untargeted liquid chromatographic-high-resolution mass spectrometric (LC-HRMS) metabolomics for potential exposure marker (PEM) discovery in nutrikinetic studies generates complex outputs. The correct selection of statistically significant PEMs is a crucial analytical step for understanding nutrition-health interactions. Hence, in this paper, different chemometric selection workflows for PEM discovery, using multivariate or univariate parametric or non-parametric data analyses, were comparatively tested and evaluated. The PEM selection protocols were applied to a small-sample-size untargeted LC-HRMS study of a longitudinal set of serum samples from 20 volunteers after a single intake of (poly)phenolic-rich Vaccinium myrtillus and Vaccinium corymbosum supplements. The non-parametric Games-Howell test identified a restricted group of significant features, thus minimizing the risk of false-positive retention. Among the forty-seven PEMs exhibiting a statistically significant postprandial kinetics, twelve were successfully annotated as purine pathway metabolites, benzoic and benzodiol metabolites, indole alkaloids, and organic and fatty acids, and five (i.e. octahydro-methyl-β-carboline-dicarboxylic acid, tetrahydro-methyl-β-carboline-dicarboxylic acid, citric acid, caprylic acid, and azelaic acid) were associated to Vaccinium berry consumption for the first time. The analysis of the area under the curve of the longitudinal dataset highlighted thirteen statistically significant PEMs discriminating the two interventions, including four intra-intervention relevant metabolites (i.e. abscisic acid glucuronide, catechol sulphate, methyl-catechol sulphate, and α-hydroxy-hippuric acid). Principal component analysis and sample classification through linear discriminant analysis performed on PEM maximum intensity confirmed the discriminating role of these PEMs.

Colorimetric selective quantification of anthocyanins with catechol/pyrogallol moiety in edible plants upon zinc complexation

Here is examined the colour development from common anthocyanins (i.e., cyanidin, delphinidin, malvidin, and pelargonidin glycosides) and from anthocyanins-rich extracts (i.e., bilberries, strawberries, and raspberries), using zinc-anthocyanin complexes as molecular probe. We have observed the absorbance increase in the blue region in presence of large excess of zinc ion at acidic pH for cyanidin and delphinidin derivatives, likely due to quinoidal base stabilization from catechol and pyrogallol moiety. The assay condition were studied and applied to natural extracts containing these compounds. The same behaviour was observed for bilberry and, to a minor extent, for raspberry extracts, due to the larger cyanidin/delphinidin contents in the former than in the latter. Anthocyanin standard UV-Vis analysis in buffer has shown a very good linear correlation for cyanidin and delphinidin (R² = 0.995 and 0.997, respectively), good precision (CV% = 7.4% and 5.3% respectively), high sensitivity (Cyε_600nm = 8300 M^-1 cm^-1, LOD = 0.264 ± 0.005 mg L^-1, LOQ = 0.478 ± 0.007 mg L^-1, and Dpε_600nm = 15,900 M^-1 cm^-1, LOD = 0.143 ± 0.002 mg L^-1, LOQ = 0.478 ± 0.007 mg L^-1). The effectiveness of this colorimetric method for the selective quantification of catechol/pyrogallol-based anthocyanins has been demonstrated in the aforementioned complex real matrices and compared to LC-MS/MS analysis and pH-differential method, offering a valuable tool to characterize plant and food extracts particularly rich in zinc-coordinating anthocyanins.

Caffeoylquinic acids: chemistry, biosynthesis, occurrence, analytical challenges, and bioactivity

Caffeoylquinic acids (CQAs) are specialized plant metabolites we encounter in our daily life. Humans consume CQAs in mg-to-gram quantities through dietary consumption of plant products. CQAs are considered beneficial for human health, mainly due to their anti-inflammatory and antioxidant properties. Recently, new biosynthetic pathways via a peroxidase-type p-coumaric acid 3-hydroxylase enzyme were discovered. More recently, a new GDSL lipase-like enzyme able to transform monoCQAs into diCQA was identified in Ipomoea batatas. CQAs were recently linked to memory improvement; they seem to be strong indirect antioxidants via Nrf2 activation. However, there is a prevalent confusion in the designation and nomenclature of different CQA isomers. Such inconsistencies are critical and complicate bioactivity assessment since different isomers differ in bioactivity and potency. A detailed explanation regarding the origin of such confusion is provided, and a recommendation to unify nomenclature is suggested. Furthermore, for studies on CQA bioactivity, plant-based laboratory animal diets contain CQAs, which makes it difficult to include proper control groups for comparison. Therefore, a synthetic diet free of CQAs is advised to avoid interferences since some CQAs may produce bioactivity even at nanomolar levels. Biotransformation of CQAs by gut microbiota, the discovery of new enzymatic biosynthetic and metabolic pathways, dietary assessment, and assessment of biological properties with potential for drug development are areas of active, ongoing research. This review is focused on the chemistry, biosynthesis, occurrence, analytical challenges, and bioactivity recently reported for mono-, di-, tri-, and tetraCQAs.

Bilberry (Vaccinium myrtillus L.) Powder Has Anticarcinogenic Effects on Oral Carcinoma In Vitro and In Vivo

Previous studies indicate that bilberry with high amounts of phenolic compounds can inhibit carcinogenic processes of colorectal cancer in vitro and in vivo. However, no studies have focused on the effects of bilberry on oral cancer. In this study, we aimed to examine the effects of bilberry powder on oral squamous cell carcinoma (OSCC) cells using both in vitro and in vivo assays. The effects of 0, 1, 10, and 25 mg/mL of whole bilberry powder on the viability, proliferation, migration, and invasion of OSCC (HSC-3) cells were examined and compared with 0.01 mg/mL of cetuximab. Two oral keratinocyte cell lines served as controls. Tumor area was analyzed in zebrafish microinjected with HSC-3 cells and treated with 2.5, 10, or 25 µg/mL of bilberry powder. Metastases in the head or tail areas were counted. Bilberry powder inhibited the viability, proliferation, migration, and invasion of HSC-3 cells (p < 0.05), which was more pronounced with higher concentrations. Cetuximab had no effect on HSC-3 cell migration or invasion. Compared to controls, the tumor area in zebrafish treated with bilberry powder (10 and 25 µg/mL) was reduced significantly (p = 0.038 and p = 0.021, respectively), but the number of fish with metastases did not differ between groups. Based on our in vitro and in vivo experiments, we conclude that whole bilberry powder has anti-tumor effects on OSCC cells.

Productivity and nutritional and nutraceutical value of strawberry fruits (Fragaria x ananassa Duch.) cultivated under irrigation with treated wastewaters

BACKGROUND

Agriculture represents a productive sector typically characterized by a high water demand, whereas freshwater (FW) availability is a problem of increasing concern in the world and FW resources are becoming insufficient for sustaining agricultural irrigation. The reuse of treated wastewaters (TWWs) for crop irrigation could be an efficient tool for reducing water shortage. Hence, the present study evaluated the food quality of Fragaria x ananassa (cultivar Camarosa) fruits irrigated with four types of treated wastewaters (TWWs). Strawberries were analysed for yield, sucrose, fructose, glucose, total soluble polyphenols (TSP), total monomeric anthocyanins (TMA), and antiradical and antioxidant capacity. In addition, a targeted quantification of the most representative phenolic compounds of strawberry was performed.

RESULTS

TWWs complied the Italian ministerial decree 185/2003 for wastewater reuse, with very few exceptions, mainly represented by chloride concentrations (258-643 mg L^-1 versus a legal threshold of 250 mg L^-1 ). The reuse of TWWs reduced fruit yield (10-26%) compared to irrigation with tap water as a control. Irrigation with TWWs gave also rise to the decrease of total sugars (14-26%), TSP (2-10%) and TMA (29-49%). Individual phenolic acids, flavonols and flavanols were quite stable in response to the irrigation with TWWs, whereas anthocyanidins decreased significantly.

CONCLUSION

Although TWWs negatively affected fruit quality, the nutritional and nutraceutical parameters determined in the present study were in line with data previously reported for strawberries purchased in the market or cultivated in research orchards, thus suggesting that the use of TWWs does not prevent the fruit marketability. © 2020 Society of Chemical Industry.

Chemical Profile, Antioxidant, Anti-Proliferative, Anticoagulant and Mutagenic Effects of a Hydroalcoholic Extract of Tuscan Rosmarinus officinalis

This study aimed to characterize the chemical profile of an ethanolic extract of Tuscan Rosmarinus officinalis (Roex) and to determine its in vitro bioactivity. The content of phenolic and flavonoid compounds, hydroxycinnamic acids and triterpenoids was determined, and high-performance liquid chromatography-diode array detection (HPLC-DAD) analysis revealed that rosmarinic acid and other hydroxycinnamic derivatives were the main constituents of the extract. Roex demonstrated to have both antioxidant activity and the capability to scavenge hydrogen peroxide in a concentration dependent manner. Moreover, NIH3T3 mouse fibroblasts and human breast adenocarcinoma cells MDA-MB-231 viability was influenced by the extract with an IC₅₀ of 2.4 × 10^-1 mg/mL and 4.8 × 10^-1 mg/mL, respectively. The addition of Roex to the culture medium of both the above cell lines, resulted also in the reduction of cell death after H₂O₂ pre-treatment. The Ames test demonstrated that Roex was not genotoxic towards both TA98 and TA100 strains, with and without S9 metabolic activation. The extract, by inactivating thrombin, showed to also have an anti-coagulating effect at low concentration values. All these biological activities exerted by Roex are tightly correlated to its phytochemical profile, rich in bioactive compounds.

Screening of Phenolic Compounds in Australian Grown Berries by LC-ESI-QTOF-MS/MS and Determination of Their Antioxidant Potential

Berries are grown worldwide with the most consumed berries being blackberries (Rubus spp.), blueberries (Vaccinium corymbosum), red raspberries (Rubus idaeus) and strawberries (Fragaria spp.). Berries are either consumed fresh, frozen, or processed into wines, juices, and jams. In recent times, researchers have focused their attention on berries due to their abundance in phenolic compounds. The current study aimed to evaluate the phenolic content and their antioxidant potential followed by characterization and quantification using LC-ESI-QTOF-MS/MS and HPLC-PDA. Blueberries were highest in TPC (2.93 ± 0.07 mg GAE/gf.w.) and TFC (70.31 ± 1.21 µg QE/gf.w.), whereas the blackberries had the highest content in TTC (11.32 ± 0.13 mg CE/gf.w.). Blueberries had the highest radical scavenging capacities for the DPPH (1.69 ± 0.09 mg AAE/gf.w.), FRAP (367.43 ± 3.09 µg AAE/gf.w.), TAC (1.47 ± 0.20 mg AAE/gf.w.) and ABTS was highest in strawberries (3.67 ± 0.14 mg AAE/gf.w.). LC-ESI-QTOF-MS/MS study identified a total of 65 compounds including 42 compounds in strawberries, 30 compounds in raspberries, 28 compounds in blueberries and 21 compounds in blackberries. The HPLC-PDA quantification observed phenolic acid (p-hydroxybenzoic) and flavonoid (quercetin-3-rhamnoside) higher in blueberries compared to other berries. Our study showed the presence of phenolic acids and provides information to be utilized as an ingredient in food, pharmaceutical and nutraceutical industries.

Green and cost-effective synthesis of copper nanoparticles by extracts of non-edible and waste plant materials from Vaccinium species: Characterization and antimicrobial activity

The aim of this work was the green synthesis of copper nanoparticles (Cu-NPs) using aqueous extracts of (i) bilberry (Vaccinium myrtillus L.) waste residues from the production of fruit juices and (ii) non-edible "false bilberry" fruits (Vaccinium uliginosum L. subsp. gaultherioides). Different cupric salts (CuCl₂, Cu(CH₃COO)₂ and Cu(NO₃)₂) were used for the synthesis. The formation of stable nanoparticles (CuNPs) was assessed by transmission electron microscopy and the oxidation state of copper in these aggregates was followed by X-ray photoelectron spectroscopy. The polyphenol composition of the extracts was characterized, before and after the synthesis, using spectrophotometric methods (i.e. total soluble polyphenols and total monomeric anthocyanins) and high-performance liquid chromatography coupled with tandem mass spectrometry (i.e. individual anthocyanins). Polyphenol concentration in the extracts was found to decrease after the synthesis, indicating their active participation to the processes, which led to the formation of Cu-NPs. The antimicrobial activity of Cu-NPs, berry extracts, and cupric ion solutions were analysed by broth microdilution and time-kill assays, on prokaryotic and eukaryotic models. The antimicrobial activity of Cu-NPs, especially those derived from bilberry waste residues, appeared to be higher for both Gram-negative and Gram-positive bacteria, and for fungi, compared to the ones of its single components (cupric salts and berry extracts). Therefore, Cu-NPs from the green synthesis here proposed can be considered as a cost-effective sanitization tool with a wide spectrum of action.

Assessment of the In Vivo Antioxidant Activity of an Anthocyanin-Rich Bilberry Extract Using the Caenorhabditis elegans Model

Anthocyanins have been associated with several health benefits, although the responsible mechanisms are not well established yet. In the present study, an anthocyanin-rich extract from bilberry (Vaccinium myrtillus L.) was tested in order to evaluate its capacity to modulate reactive oxygen species (ROS) production and resistance to thermally induced oxidative stress, using the nematode Caenorhabditis elegans as an in vivo model. The assays were carried out with the wild-type N2 strain and the mutant strains daf-16(mu86) I and hsf-1(sy441), which were grown in the presence of two anthocyanin extract concentrations (5 and 10 μg/mL in the culture medium) and further subjected to thermal stress. The treatment with the anthocyanin extract at 5 μg/mL showed protective effects on the accumulation of ROS and increased thermal resistance in C. elegans, both in stressed and non-stressed young and aged worms. However, detrimental effects were observed in nematodes treated with 10 μg/mL, leading to a higher worm mortality rate compared to controls, which was interpreted as a hormetic response. These findings suggested that the effects of the bilberry extract on C. elegans might not rely on its direct antioxidant capacity, but other mechanisms could also be involved. Additional assays were performed in two mutant strains with loss-of-function for DAF-16 (abnormal DAuer Formation factor 16) and HSF-1 (Heat Shock Factor 1) transcription factors, which act downstream of the insulin/insulin like growth factor-1 (IGF-1) signaling pathway. The results indicated that the modulation of these factors could be behind the improvement in the resistance against thermal stress produced by bilberry anthocyanins in young individuals, whereas they do not totally explain the effects produced in worms in the post-reproductive development stage. Further experiments are needed to continue uncovering the mechanisms behind the biological effects of anthocyanins in living organisms, as well as to establish whether they fall within the hormesis concept.

The Influence of Local Habitat and Microclimate on the Levels of Secondary Metabolites in Slovak Bilberry (Vaccinium myrtillus L.) Fruits

The berries of Vaccinium myrtillus L. are usually collected in the wild for the purpose of being a food source. They are naturally high in phenolic compounds, which possess antioxidative properties, so the berries are therefore often labeled as “functional foods”. This study evaluated seven samples of bilberry fruits from different locations in Slovakia for the content of the main phenolic compounds (anthocyanins, flavonoids and tannins) using European Pharmacopoeia 9 spectrophotometric methods. A thorough analysis of environmental factors showed that several phenolic constituents are closely corresponding with their respective environments, as well as with each other. The environmental factors with statistically significant correlations in this study are altitude, habitat type, sunlight exposure, and soil carbon content. Our findings suggest that the berries collected at sunny sites with no topsoil damage contain more phenolic compounds. The lowest amounts of phenolic compounds were found in samples from dense forests or with visible soil erosion and windthrow damage. The negative effect of windthrow damage on the levels of secondary metabolites in bilberry fruits has been described for the first time. This study observed no relationship between the amount of phenolic compounds and soil pH, soil nitrogen levels, or slope exposition.

Blueberry Juice Antioxidants Protect Osteogenic Activity against Oxidative Stress and Improve Long-Term Activation of the Mineralization Process in Human Osteoblast-Like SaOS-2 Cells: Involvement of SIRT1

Diets rich in fruits and vegetables with many antioxidants can be very important in the prevention and treatment of osteoporosis. Studies show that oxidative stress, often due to lack of antioxidants, is involved in alteration of bone remodeling and reduction in bone density. This study demonstrates in human osteoblast-like SaOS-2 cells that blueberry juice (BJ), containing 7.5 or 15 μg∙mL^-1 total soluble polyphenols (TSP), is able to prevent the inhibition of osteogenic differentiation and the mineralization process due to oxidative stress induced by glutathione depletion. This situation mimics a metabolic condition of oxidative stress that may occur during estrogen deficiency. The effect of BJ phytochemicals occurs through redox- and non-redox-regulated mechanisms. BJ protects from oxidative damage factors related to bone remodeling and bone formation, such as alkaline phosphatase and Runt-related transcription factor 2. It upregulates these factors by activation of sirtuin type 1 deacetylase expression, a possible molecular target for anti-osteoporotic drugs. Quantitative analysis of TSP in BJ shows high levels of anthocyanins with high antioxidant capacity and bioavailability. These novel data may be important to elucidate the molecular and cellular beneficial effects of blueberry polyphenols on bone regeneration, and they suggest their use as a dietary supplement for osteoporosis prevention and therapies.

Vaccinium myrtillus L. Fruits as a Novel Source of Phenolic Compounds with Health Benefits and Industrial Applications - A Review

Consumers' demand for healthier foods with functional properties has had a clear influence on the food industry and in this sense, they have been attaching natural sources of bioactive ingredients into food products. Vaccinium myrtillus L. (bilberry) is known to be a functional food, presenting its fruits in the form of a small dark blueberry. This coloration is due to its high content in anthocyanin, being also associated with bilberries' beneficial health effects. In the bilberry industry, there is a very high annual loss of this fruit due to the less aesthetic shape or appearance, in which they cannot be considered suitable for sale and are therefore disposed of as biological waste. Therefore, it is of great importance to valorize this fruit and this review aimed to completely characterize the fruits of V. myrtillus in order to comprehend the relationship between their consumption and the beneficial effects regarding consumer's health. Thus, this review provides a description of the nutritional and bioactive compounds present in bilberry fruits, followed by their beneficial health effects. An overview of the natural pigments present in these fruits was also explored, focusing particularly in the anthocyanins composition, which represents the most widely studied class of bioactive compounds of V. myrtillus fruits. Finally, industrial applications of these fruits and by-products, as an efficient approach to the production of value-added products with economical and environmental impact, were also discussed. In general, V. myrtillus is a rich source of micronutrients and phytochemical compounds, such as organic acids, sugars, vitamins, fibers and phenolic compounds (anthocyanin and non-anthocyanin compounds), with nutritional and functional properties, that justify the growing interest in these berries, not only for food applications, but also in the pharmaceutical industry.

Preclinical and clinical results regarding the effects of a plant-based antidiabetic formulation versus well established antidiabetic molecules

Diabetes mellitus (DM) is a complex syndrome with debilitating long-term complications, comprising alterations of carbohydrate, protein and lipid metabolisms, along increased oxidative stress and chronic low-grade inflammation. Diet management and plant-based formulations can improve the metabolic status of patients, being used as adjuvants of classic antidiabetic therapy. The purpose of our study was to evaluate the impact of a plant-based antidiabetic formulation (PBAF), containing Vaccinium myrtillus, Ribes nigrum, Rosa canina and Capsicum annuum, on the increased oxidative burden found in diabetes mellitus, comparing it with the effects of metformin and gliclazide. Firstly, we characterized the individual plant-derived components of this formulation and also assessed their in vitro radical scavenging capacity. We devised a preclinical study protocol to examine the impact of the PBAF, along metformin and gliclazide, on tissue histology as well as on the redox status of tissue, mitochondria, serum and serum lipoproteins of alloxan-induced diabetic Wistar rats. Subsequently, we assessed their long-term impact on the redox status of serum and isolated serum lipoproteins of type 2 DM (T2DM) patients, taking into consideration their cardiometabolic profile. In the preclinical stage, we found that PBAF was able to enhance total serum antioxidant defense, while metformin yielded the best results regarding the advanced glycation and protein/lipid oxidation of serum and of serum lipoproteins. The latter also improved overall serum redox status and HDL redox function. Also, antidiabetic treatment seemed to increase mitochondrial redox activity, without overturning overall tissue redox balance. Histologically, liver and brain tissues of treated diabetic rats were fairly similar to those of non-diabetic rats. In T2DM patients, the most striking results involved the effects on serum lipoproteins. The tested PBAF exerted protective antioxidant effects on low-density and, especially, on high density lipoproteins. We conclude that this formulation might constitute a good addition to the well-established pharmacological approach of DM, contributing to the reduction of overall oxidative burden.

Phenylpropanoids and lignoids from the whole plant of Vaccinium emarginatum and their cytotoxicity against prostate cancer cells

One new naturally occurring quinone, 3',4'-dihydroxy-1,2,6-trimethoxy-[1,1'-biphenyl]-4(1H)-one (1), one new diarylpropane, emarginone A (2), and one new neolignan, emarginone B (3), along with eighteen known compounds have been isolated from the chemical investigation of the EtOAc-soluble fraction of the Vaccinium emarginatum whole plant methanolic extract. The new structures were elucidated by combined analysis of spectroscopic analytical methods and comparison with the literature data obtained from known analogues. In addition, the cytotoxicity of compounds 2, 4, and 14-20 against Du145 and PC-3 prostate cancer cell lines using MTT cell proliferation assay was evaluated. Compounds 2 and 19 showed most potent cytotoxicity against Du145 with IC₅₀ values of 7.53 and 6.63 μg/mL, respectively. Furthermore, compounds 2, 17, and 19 also exhibited significant cytotoxicity against PC-3 with IC₅₀ values ranging from 3.44-6.64 μg/mL.

Blueberry juice protects osteocytes and bone precursor cells against oxidative stress partly through SIRT1

Oxidative stress and abnormal osteocyte apoptosis are often related to dysregulation of bone turnover and chronic bone loss, and so fruit and vegetables with high antioxidant potential may play an important role in the prevention and/or management of osteoporosis. Osteocytes are the main regulators of bone remodelling. For the first time, we demonstrate here that blueberry juice (BJ), obtained from Vaccinium myrtillus, rich in polyphenols, shows antioxidant and antiosteoclastogenic properties in MLO‐Y4 osteocytes. We report that BJ prevents oxidative stress‐induced apoptosis and reverses the increase in receptor activator of nuclear factor κB ligand and sclerostin expression, crucial factors for osteoclast activation and bone resorption. BJ is also able to prevent oxidative stress‐induced cell cytotoxicity in bone marrow mesenchymal stromal cells (MSCs), which are considered to be an important tool for cell therapy in bone disorders. No significant difference in preventing these events was observed between BJ and blueberry dry extract containing equal amounts of total soluble polyphenols. We have also shown that blueberry acts as both an antioxidant and an activator of sirtuin type 1, a class III histone deacetylase involved in cell death regulation and considered a molecular target for blocking bone resorption without affecting osteoclast survival. Overall, these novel data obtained in osteocytes and MSCs may help us clarify the mechanisms by which blueberry counteracts oxidative stress‐induced damage in bone remodelling and osteogenesis at the cellular and molecular level. Our findings are consistent with the reported beneficial effects of blueberry on bone tissue reported in animal studies, which suggest that blueberry may be a useful supplement for the prevention and/or management of osteoporosis and osteogenic process.

Untargeted Metabolomics Analytical Strategy Based on Liquid Chromatography/Electrospray Ionization Linear Ion Trap Quadrupole/Orbitrap Mass Spectrometry for Discovering New Polyphenol Metabolites in Human Biofluids after Acute Ingestion of Vaccinium myrtillus Berry Supplement

In this work, liquid chromatography, coupled with an electrospray ionization hybrid linear ion trap quadrupole/Orbitrap mass spectrometry, has been used to accurately identify polyphenol metabolites in human serum and urine after acute ingestion of a V. myrtillus berry supplement. The supplement was obtained by cryo-milling of bilberries, which were freeze-dried within 1 week after their harvesting, to maintain the berry native composition. Thirty-six derivatives of benzoic acids, hydroxyhippuric acids, cinnamic acids, phenylpropionic acids, phenylvaleric acids, phenylpentenoic acids and abscisic acid, together with two berry-native anthocyanins, one flavonol metabolite and two catechol derivatives were putatively identified in the investigated biofluids. The annotated compounds included 13 metabolites, among glucuronides and sulphates of phenylvaleric and phenylpentenoic acids, which have been identified for the first time in human biofluids after ingestion of V. myrtillus berries. It should be emphasized that the presence of phenylvaleric and phenylpentenoic acid derivatives is in agreement with their origin from fruit native flavanol monomers and oligomers, which are widely distributed in Vaccinium berries, but usually overlooked in metabolomics studies regarding bilberry. The identification of these compounds confirmed the key-role of untargeted metabolomics approach in the discovery of new metabolites which could be biologically active. Graphical Abstract.

Ancient Tomato (Solanum lycopersicum L.) Varieties of Tuscany Have High Contents of Bioactive Compounds

The Tuscan Region has a vast repertoire of ancient plants that have been recovered across the territory over the years. These plants thrive in an environment characterized by minimal human intervention and are thus the result of the process of adaptation to the territory of origin. In this work, we focused on the quantification of bioactive compounds in ancient tomato varieties. More specifically, we quantified polyphenols, flavonoids, carotenoids, and vitamin C in eight local Tuscan tomato varieties and found higher contents with respect to those in commercial tomatoes Polyphenol and antioxidant compounds in ancient varieties reported a two- and, in some instances, three-fold increase in concentration, compared to the commercial counterparts. Interestingly, the data relative to the carotenoids did not show any significant differences when comparing the ancient varieties with the commercial ones, a finding confirming the market selection criterion based on color. On a longer-term perspective, this study aims at drawing attention to the importance of preserving autochthonous natural plant biodiversity and towards promoting research on local varieties. We believe that this study will pave the way to the valorization of local plant biodiversity and promote an extended use of products in the nutraceutical sector derived from vegetables.

Are Processed Bilberry Products a Good Source of Phenolics?

Bilberries are processed into different food products and beverages. Therefore, we studied how various bilberry items (puree, infusion, liqueur, and fresh and pasteurized juices) differ in secondary metabolites as compared to the fresh fruit. For this purpose, we identified phenolics with a liquid chromatography-mass spectrophotometry (LC-MS) system and compared phenolic profiles and phenolic contents in various bilberry products prepared from the same raw material. Our results show that processing significantly affected the biochemical pattern and levels of phenolics. Total analyzed phenolics decreased with processing, mostly due to anthocyanins, which had the highest share in phenolic profile of all bilberry-based products. The highest differences among products in flavanol (63.7-fold), followed by flavonol contents (26.3-fold). Fresh fruits had the highest content of total anthocyanins (5,190 mg/100 g dry weight [DW]), followed by puree (2,719 mg/100 g DW), infusion (2,469 mg/100 g DW), and liqueur (1,830 mg/100 g DW), whereas fresh and pasteurized juices had the lowest content of total anthocyanins (921 and 1,099 mg/100 g DW).

PRACTICAL APPLICATION

Although we confirmed the common belief among consumers that the consumption of fresh berries is more beneficial than consuming processed products, this study showed that various bilberry-derived products can also be valuable source of phenolic compounds all year round.

Functional Molecules in Locally-Adapted Crops: The Case Study of Tomatoes, Onions, and Sweet Cherry Fruits From Tuscany in Italy

The human diet is characterized by highly energetic molecules, but it also requires non-energetic compounds that are equally useful for cell functioning and for preserving the organism's health status. These "functional" molecules are represented by a wide variety of plant secondary metabolites, such as terpenoids, vitamins and polyphenols with antioxidant power. Widespread commercial crop varieties often contain scarce levels of functional molecules, because they have been mostly selected for productivity, rather than for the content of secondary metabolites. Different scenarios (global economic situation, foreseeable environmental changes) are pushing farmers to review the use of high yield crops and to focus on the valorization of locally-adapted plants. This renewed interest is strengthened by the growing need of consumers for functional foods with beneficial effects on human health and by the willingness to promote sustainable low-input agricultural practices exploiting local climate, soil, water, and (micro)biota. Here, we want to discuss a specific case study concerning locally-adapted crops in Tuscany (Italy). Analyses of nutraceutical molecules in locally-grown crop varieties (namely tomatoes, sweet cherries and onions) have shown that they are characterized by substantially higher functional molecule contents than commercial varieties. Our goal is to promote the high-throughput study of locally-adapted varieties to understand, in a medium-term perspective, whether the cultivation of such plants is a valuable support for the diet and an adequate local economic resource. Such plants can provide a boost to the regional economy, by diversifying the local crop-market landscape. Moreover, the exploitation of locally-grown plants results in the manufacture of fully-traceable products (from the raw bioresource to the finished product) with a "0 km" concept that minimizes the C footprint.

Distinguishing Six Edible Berries Based on Metabolic Pathway and Bioactivity Correlations by Non-targeted Metabolite Profiling

Berries have been used as valuable sources of polyphenols for human health; however, injudicious uses of berries are widespread without regard to the specific metabolite constituent of each berry. We classified 6 different edible berries (honeyberry, blueberry, mandarin melonberry, mulberry, chokeberry, and Korean black raspberry) based on their metabolite distributions in biosynthetic pathways by non-targeted metabolite profiling and bioactive correlation analysis. Principal component analysis revealed a distinct clustering pattern of metabolites for each berry. Metabolic pathway analysis revealed different biosynthetic routes of secondary metabolites in each berry. Mandarin melonberry contains a relatively higher proportion of genistein, genistein glycoside, and genistein-derived isoflavonoids and prenylflavonoids than the other berries. Various anthocyanin glycosides, synthesized from dihydroquercetin and cyanidin, were more abundant in chokeberry and honeyberry, whereas high levels of flavonoid-and anthocyanins-rutinoside forms were observed in Korean black raspberry. The levels of anthocyanins derived from dihydromyricetin were high in blueberry. The highest anti-oxidant activity was observed in chokeberry and Korean black raspberry, which is positively related to the proportional concentration of flavonoids, phenolics, and anthocyanins. The lowest sugar contents were observed in Korean black raspberry, highest acidity in honeyberry, and lowest acidity in mandarin melonberry, which were specific characteristics among the berries. Taken together, biosynthetic pathway and physicochemical characteristics analyses revealed that the different synthesized routes of flavonoids and anthocyanins and associated bio-activities may be distinct features in each berry and explain their phenotypic diversity at the molecular level.

On the Developmental and Environmental Regulation of Secondary Metabolism in Vaccinium spp. Berries

Secondary metabolites have important defense and signaling roles, and they contribute to the overall quality of developing and ripening fruits. Blueberries, bilberries, cranberries, and other Vaccinium berries are fleshy berry fruits recognized for the high levels of bioactive compounds, especially anthocyanin pigments. Besides anthocyanins and other products of the phenylpropanoid and flavonoid pathways, these berries also contain other metabolites of interest, such as carotenoid derivatives, vitamins and flavor compounds. Recently, new information has been achieved on the mechanisms related with developmental, environmental, and genetic factors involved in the regulation of secondary metabolism in Vaccinium fruits. Especially light conditions and temperature are demonstrated to have a prominent role on the composition of phenolic compounds. The present review focuses on the studies on mechanisms associated with the regulation of key secondary metabolites, mainly phenolic compounds, in Vaccinium berries. The advances in the research concerning biosynthesis of phenolic compounds in Vaccinium species, including specific studies with mutant genotypes in addition to controlled and field experiments on the genotype × environment (G×E) interaction, are discussed. The recently published Vaccinium transcriptome and genome databases provide new tools for the studies on the metabolic routes.