Blueberry Anthocyanins Research Articles

Acute cognitive and blood glucose effects of blueberry anthocyanins in healthy young adults

Acute cognitive and blood glucose effects of blueberry anthocyanins in healthy young adults

Protective Effects of Blueberry Anthocyanins against H2O2-Induced Oxidative Injuries in Human Retinal Pigment Epithelial Cells

Blueberry anthocyanins are considered protective of eye health because of their recognized antioxidant properties. In this study, blueberry anthocyanin extract (BAE), malvidin (Mv), malvidin-3-glucoside (Mv-3-glc), and malvidin-3-galactoside (Mv-3-gal) all reduced H2O2-induced oxidative stress by decreasing the levels of reactive oxygen species and malondialdehyde and increasing the levels of superoxide dismutase, catalase, and glutathione peroxidase in human retinal pigment epithelial cells. BAE and the anthocyanin standards enhanced cell viability from 63.69 ± 3.36 to 86.57 ± 6.92% (BAE), 115.72 ± 23.41% (Mv), 98.15 ± 9.39% (Mv-3-glc), and 127.97 ± 20.09% (Mv-3-gal) and significantly inhibited cell apoptosis (P < 0.01 for all). Mitogen-activated-protein-kinase pathways, including ERK1/2 and p38, were involved in the bioactivities. In addition, the anthocyanins decreased vascular-endothelial-cell-growth-factor levels and activated Akt-signal pathways. These combined results supported the hypothesis that blueberry anthocyanins could inhibit the induction and progression of age-related macular degeneration (AMD) through antioxidant mechanisms.

Blackberry and Blueberry Anthocyanin Supplementation Counteract High-Fat-Diet-Induced Obesity by Alleviating Oxidative Stress and Inflammation and Accelerating Energy Expenditure.

Many studies indicate that an anthocyanin-rich diet has beneficial effects preventing metabolic disease. In the present study, the molecular mechanism underlying the antiobesity effect of consuming blackberry anthocyanins (BLA) and blueberry anthocyanins (BBA) was investigated in high-fat-diet- (HFD-) fed C57BL/6 mice. Sixty mice were administered a low-fat diet (LFD), a HFD, or a HFD plus orlistat, and BLA or BBA in their daily food for 12 weeks. As a result, the consumption of BLA and BBA inhibited body weight gain by 40.5% and 55.4%, respectively, in HFD-fed mice. The BLA and BBA treatments markedly reduced serum and hepatic lipid levels and significantly increased hepatic superoxide dismutase and glutathione peroxidase activities. In addition, the treatments effectively increased fecal acetate and butyrate levels and significantly attenuated expression of tumor necrosis factor TNF-α, interleukin-6, and nuclear factor-kappaB genes. Moreover, gas chromatography time-of-flight mass spectroscopy results suggested that BLA and BBA significantly affected the hepatic lipid and glucose metabolic pathways, including glycerophospholipid metabolism, glutathione metabolism, and the insulin-signaling pathway. Therefore, BLA and BBA ameliorated diet-induced obesity by alleviating oxidative stress and inflammation and accelerating energy expenditure.

Antioxidant and Anti-Inflammatory Effects of Blueberry Anthocyanins on High Glucose-Induced Human Retinal Capillary Endothelial Cells.

Blueberries possess abundant anthocyanins, which benefit eye health. The purpose of this study was to explore the protective functional role of blueberry anthocyanin extract (BAE) and its predominant constituents, malvidin (Mv), malvidin-3-glucoside (Mv-3-glc), and malvidin-3-galactoside (Mv-3-gal), on high glucose- (HG-) induced injury in human retinal capillary endothelial cells (HRCECs). The results showed that BAE, Mv, Mv-3-glc, and Mv-3-gal enhanced cell viability (P < 0.05 versus the HG group at 24 h); decreased the reactive oxygen species (ROS, P < 0.01 versus the HG group both at 24 and 48 h); and increased the enzyme activity of catalase (CAT) and superoxide dismutase (SOD) (P < 0.05 versus the HG group both at 24 and 48 h). Mv could greatly inhibit HG-induced Nox4 expression both at 24 and 48 h (P < 0.05), while BAE and Mv-3-gal downregulated Nox4 only at 48 h (P < 0.05). Mv, Mv-3-glc, and Mv-3-gal also changed nitric oxide (NO) levels (P < 0.05). BAE and Mv-3-glc also influenced angiogenesis by decreasing the vascular endothelial cell growth factor (VEGF) level and inhibiting Akt pathway (P < 0.05). Moreover, Mv and Mv-3-glc inhibited HG-induced intercellular adhesion molecule-1 (ICAM-1, P < 0.001) and nuclear factor-kappa B (NF-κB) (P < 0.05). It indicated that blueberry anthocyanins protected HRCECs via antioxidant and anti-inflammatory mechanisms, which could be promising molecules for the development of nutraceuticals to prevent diabetic retinopathy.

Malvidin and its Glycosides from Vaccinium ashei Improve Endothelial Function by Anti-inflammatory and Angiotensin I-Converting Enzyme Inhibitory Effects

Protective effects of malvidin and the glycosides from Vaccinium ashei on endothelial cells were investigated. The results showed that malvidin, malvidin-3-glucoside, malvidin-3-galactoside, and their mixture could defend endothelial cells from damage caused by TNF-α, and inhibit monocyte chemotactic protein-1, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and angiotensin I-converting enzyme expression. In addition, they could inhibit degradation of IκBα and obstruct the nuclear translocation of p65, suggesting the anti-inflammatory mechanism of NF-κB pathway. The results indicated blueberry anthocyanins could be potential inflammation and ACE inhibitors, and blueberry could be functional foods advantageous to maintain a healthy cardiovascular population.

Blueberry Metabolites Attenuate Lipotoxicity-Induced Endothelial Dysfunction.

Lipotoxicity-induced endothelial dysfunction is an important vascular complication associated with diabetes. Clinical studies support the vascular benefits of blueberry anthocyanins, but the underlying mechanism is unclear. The hypothesis that metabolites of blueberry anthocyanins attenuate lipotoxicity-induced endothelial dysfunction was tested. Human aortic endothelial cells (HAECs) were treated for 6 h with either: (i) the parent anthocyanins (malvidin-3-glucoside and cyanidin-3-glucoside); or (ii) the blueberry metabolites (hydroxyhippuric acid, hippuric acid, benzoic acid-4-sulfate, isovanillic acid-3-sulfate, and vanillic acid-4-sulfate), at concentrations known to circulate in humans following blueberry consumption. For the last 5 h HAECs were treated with palmitate or vehicle. HAECs treated with palmitate displayed elevated reactive oxygen species generation, increased mRNA expression of NOX4, chemokines, adhesion molecules, and IκBα, exaggerated monocyte binding, and suppressed nitric oxide production. Of note, the damaging effects of palmitate were ameliorated in HAECs treated with blueberry metabolites but not parent anthocyanins. Further, important translational relevance of these results was provided by our observation that palmitate-induced endothelial dysfunction was lessened in arterial segments that incubated concurrently with blueberry metabolites. The presented findings indicate that the vascular benefits of blueberry anthocyanins are mediated by their metabolites. Blueberries might complement existing therapies to lessen vascular complications.

Extraction, Separation, and Purification of Blueberry Anthocyanin Using Ethyl Alcohol

Extraction, Separation, and Purification of Blueberry Anthocyanin Using Ethyl Alcohol

Antioxidant activity of blueberry anthocyanin extracts and their protective effects against acrylamide‐induced toxicity in HepG2 cells

SummaryIn this study, the antioxidant activities of blueberry anthocyanin extracts from ten blueberry varieties were evaluated based on the methods of scavenging activities for DPPH radicals, ABTS radicals, hydroxyl radicals and ferric reducing antioxidant power (FRAP) assay. Among the ten blueberry varieties, Polaris had the highest antioxidant abilities and the largest amounts of anthocyanins identified by HPLC‐MS. The protective effects of anthocyanin extracts from Polaris (AEP) against acrylamide (AA)‐induced toxicity in HepG2 cell models were also evaluated due to the neurotoxic, genotoxic and potentially carcinogenic effects of AA. The protective effects of AEP on the damage of HepG2 cells were explored from the aspects of cell viability, T‐SOD and CAT activity and MDA level. The AEP (5, 10, 20 μg mL−1) could significantly increase cell viability (P &lt; 0.01) and inhibit AA‐induced cytotoxicity. Polaris also markedly promoted the activity of SOD, CAT and inhibited MDA level. The results showed that AEP had strong antioxidant activities, presenting high protective effects against AA‐induced cell damage in HepG2 cell models.

Blueberry anthocyanin induces apoptosis in HepG-2 cells and the mechanism of the process

The objective of this study was to evaluate the anti-proliferation and inducing apoptosis of human hepatocellular carcinoma HepG-2 cells by anthocyanin. In order to investigate the involvement of apoptotic-related proteins and gene expression, RT-PCR, western blot, transcriptome sequencing, and appropriate biochemical assays were employed. The results indicated that anthocyanin showed significant inhibitory effect on HepG-2 cells (p < 0.05). Anthocyanin induced cell apoptosis in HepG-2 cells, increased in the generation of reactive oxygen species, decreased mitochondrial membrane potential, increased the activity caspase-3, released cytochrome c from the mitochondria into the cytosol, down-regulated the expression of Bcl-2, and up-regulated the expression of Bax. The transcriptome sequencing analysis revealed that anthocyanin activated p38 MAPK signal pathway, p53 signaling pathway and apoptotic signaling pathway in response to endoplasmic reticulum stress and inactivated TGF-beta signaling pathway. Genes involved in apoptosis included GADD45A, GADD45B, DDIT4, CHAC1, ATF-4, CDKN1A, and EPHA2. The present findings indicated that anthocyanin from blueberry can significantly induce HepG-2 cells apoptosis and might be used as an adjuvant ingredient for cancer prevention in the future.

Antioxidative capacity of crude camellia seed oil: Impact of lipophilization products of blueberry anthocyanin

ABSTRACTNatural antioxidants have received considerable research interest nowadays, especially their usage in oil products. Blueberry anthocyanin extracts were added to crude camellia seed oil and lipophilized with free fatty acids in the oil through enzymatic process. The results showed that lipophilized anthocyanin derivates were synthesized, the oxidative stability of the oil under high temperature was improved, and the content of free fatty acids of the crude camellia seed oil was decreased. In conclusion, enzymatic lipophilization of blueberry extracts with free fatty acids in crude camellia seed oil could improve the quality of oil, especially the performance under high temperature.

Comparison and screening of bioactive phenolic compounds in different blueberry cultivars: Evaluation of anti-oxidation and α-glucosidase inhibition effect

This study was aimed to investigate antioxidation and α-glucosidase inhibition of the bioactive compounds in three cultivars of blueberry (‘Northland’ (NL) from the hybrid blueberry (V. corymbosum L.×V. angustifolium Aiton), ‘Britewell’ (BW), and ‘Gardenblue’ (GB) from the rabbiteye blueberry (Vaccinium ashei Reade)). A total of eighteen anthocyanins were identified and quantified in Anthocyanins (ACNs), among which four acylated anthocyanins were exclusively found in Northland. The blueberry anthocyanin extracts (BAEs) were further measured the antioxidant activity and α-glucosidase inhibition effect. Northland BAEs exhibited significantly superior antioxidant activity compared with BAEs of other cultivars, and the antioxidant activity was correlated with the content of anthocyanins. However, α-glucosidase inhibition test showed that Britewell BAEs had the strongest inhibitory effect. BAEs were further separated into anthocyanin fraction (AF) and copigment fraction (CF). Fifteen phenolic acids and four iridoids were identified in CF. In terms of α-glucosidase inhibition effects, the CF from three cultivars could inhibit α-glucosidase in a dose-dependent manner, while the AF did not show significant inhibitory effects. The blueberry exhibits excellent antioxidant activity and α-glucosidase inhibition.

Optimization of ultrasound-assisted extraction of phenolic compounds from jussara (Euterpe edulis M.) and blueberry (Vaccinium myrtillus) fruits

Abstract This study was aimed at optimizing the ultrasound-assisted extraction (UAE) of phenolic compounds from jussara and blueberry fruits using the response surface methodology (RSM). UAE was found to be more efficient to extract phenolic compounds from both fruits than the conventional extraction. The optimum extraction conditions for the jussara fruits were: extraction time between 30 and 62 min for total anthocyanins and total phenolics, fruit:solvent ratio of 10% and 6% (w/v) for total anthocyanins and total phenolics, respectively. The ethanol concentration was non-significant (p> 0.05). Acidified water was found to be an extracting solvent as efficient as ethanol in the extraction of phenolic compounds from jussara fruits. The optimum extraction conditions for blueberry anthocyanins were: ethanol concentration between 20-70% vol, and fruit: solvent ratio greater than 20% (w/v) within the range studied. The extraction time was not significant (p> 0.05). For total phenolic content: the concentration of ethanol was between 40-80%, and fruit: solvent ratio greater than 20% (w/v) and extraction time over 50 minutes. It was possible to adjust the mathematical model for the coordinates a* (verde vs vermelho) and C* (color saturation) of the jussara extracts.

The effects of blueberry anthocyanins on histone acetylation in rat liver fibrosis.

To determine the effects ofanthocyanins from blueberries on hepatic stellate cell (HSCs-T6) and on histone acetylation during liver fibrosis induced by CCl4 in rats. Fifty male SD rats weighing 180 ± 20g were randomly placed into a control group, a hepatic fibrosis group, a blueberry treatment group, a blueberry intervention group, and a natural recovery group. After the rats were sacrificed, the livers and the liver indexes were measured, and the pathological changes were observed by HE staining and Masson staining. The blood was analyzed for the four indexes of liver fibrosis and liver function; nucleoprotein from liver tissues and karyoplasm were isolated to determine the expression of acH3K9, acH3K14, and acH3K18 by Western blotting.Compared with the lethal rate of the control group, the median lethal rate of HSCs-T6 cells treated with a the 50μmol/L concentration was 66.94% (P < 0.05). The protein expression on α-SMA, type I collagen, TIMP1 significantly decreased (P < 0.05) following treatment with 50 ug/ml of anthocyanin for 36 h; moreover, the expression of acH3K9, acH3K14 and acH3K18 modification were up-regulated (P < 0.05). Furthermore, compared with the liver in the model group, the liver in the intervention group showed the most obvious improvement (P < 0.01), and its karyoplasm had increased expression of acH3K9, acH3K14 and acH3K18 (P<0.01).Regulating histone acetylation could improve liver function and liver fibrosis indexes in rats with hepatic fibrosis. The mechanism might be related to certain genes that promote apoptosis, so as to inhibit the effect of anti hepatic fibrosis.

Metabolic Fate of Blueberry Anthocyanins after Chronic Supplementation in Healthy Older Adults

Plant derived anthocyanin rich foods play a protective role against chronic diseases such as diabetes, obesity, cardiovascular, cancer and neurodegenerative diseases. Anthocyanins are absorbed in their intact form and can be metabolized to a wide array of phenolic metabolites/conjugates. Blueberries are considered to be one of the richest source of anthocyanins and in the present study, we explored the metabolic fate of blueberry anthocyanins after chronic (90 days) supplementation of freeze‐dried blueberry (24 g/d, equivalent to 1 cup of fresh blueberries) in 19 healthy older adults (67.8 ± 4.6 y). Blood samples were collected at baseline (t=0 h) and 2 h post consumption on day 1 (no treatment), day 45 and day 90. A total of 28 anthocyanin metabolites were identified in plasma using ultra high‐performance liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometer. Peonidin glucuronide, a conjugated metabolite of peonidin, reached 204.5 ± 87.5 nmol/L at 2 h on day 45, which was the highest concentration among all phase II metabolites maintaining the parent structure. Among the parent untransformed anthocyanins, the content of malvidin galactoside was highest (37.4 ± 10.4 nmol/L) while the content of cyanidin glucoside was lowest (10.0 ± 2.9 nmol/L) in 2 h plasma sample on day 45. Out of 14 phenolic acid metabolites, the concentration of 7 metabolites were increased in baseline plasma at day 45 and 90 when compared to baseline plasma at day 1. The concentration of twelve phenolic acid metabolites increased at 2 h when compared to 0 h on day 45 and 90. Ferulic acid, vanillic acid, syringic acid and ferulic acid glucuronide were detected only in 2 h plasma samples. Our results suggest that blueberry anthocyanins are absorbed and extensively metabolized/catabolized resulting in the production of various phenolic acid derivatives and their conjugates, all together contributing to the bioavailability and beneficial effects associated with blueberry consumption.Support or Funding InformationU.S. Department of Agriculture, U.S. Highbush Blueberry Council, Tufts University and Investigator (Burton‐Freeman/Edirisinghe) various donor funds.

Flavonoid Metabolites in Human Urine during Blueberry Anthocyanin Intake.

The human health benefits of anthocyanins (Anc) and other flavonoids are widely recognized. However, the flavonoid-based urinary metabolites arising in vivo after Anc intake are not well described. Human (n = 17) urine was collected while blueberry juice (BJ) was consumed daily for 28 days and once after a 7 day washout. MS/MS scanning of 664 urine samples for 18 parent Anc (PAnc) and 42 predicted Anc metabolites (AncM) yielded 371 products (i.e., MS/MS × retention time (RT)). Flavonoid-based AncM, which were likely underestimated, were almost 20 times more abundant than PAnc. Together, PAnc and AncM accounted for about 1% of the daily Anc dose. Aglycone forms were >94% of the total. Cluster analysis of the 371 Anc identified about 55 major Anc that contributed about 80% to the total Anc. The abundance of flavonoid-based Anc-derived products in the gastrointestinal tract could contribute to the health benefits of Anc-rich berries.

Stability of blueberry (Cornus mas – Yulyush) anthocyanin pigment under pH and co-pigment treatments

ABSTRACTIn this study, the effects of different pH values and co-pigments, including tannic, caffeic, benzoic, and coumaric acids, in various concentrations on anthocyanin co-pigment complexes (ratio 1:1) were investigated. The anthocyanin was extracted from a round sweet variety of blueberry and subjected to the highest co-pigment concentration (960 mg/l) at different pH values. The results showed that caffeic acid produced the highest stability of anthocyanin compared to the other co-pigments. In addition, benzoic acid had the lowest hyperchromic and bathochromic changes. A positive correlation was found between the co-pigment concentrations and the stability of anthocyanin as well as hyperchromic and bathochromic changes. The results also demonstrated that higher pH values resulted in further destruction of anthocyanin. Furthermore, the absorption rate of anthocyanin in the anthocyanin–co-pigment complex within lower pH values was more compared with the higher ones. The strongest hyperchromic and bathochromic effects for all organic acids were observed in pH values 1 and 4, respectively. It can be concluded that among the tested co-pigments, caffeic acid was the best co-pigment, while benzoic acid was the weakest, which was not suitable for anthocyanin in the round sweet variety of blueberry.

Combining various wall materials for encapsulation of blueberry anthocyanin extracts: Optimization by artificial neural network and genetic algorithm and a comprehensive analysis of anthocyanin powder properties

Various wall materials, including maltodextrin (MD), β-cyclodextrin (β-CD), whey protein isolate (WPI) and gum Arabic (Gum-A) were combined together as the wall materials for encapsulation of blueberry anthocyanin extracts through freeze drying. Simplex lattice mixture design was used to make the experimental design. Artificial neural network (ANN) combined with genetic algorithm (GA) was successfully applied to model the influences of formulation composition on encapsulation productivity (EP) and encapsulation efficiency (EE), as well as obtain optimum formulations. Four optimum formulations were provided by the ANN-GA approach. In all the optimum formulations, WPI had the highest content. Using the optimum formulations, EP values were higher than 96% and EE values exceeded 82%. On the other hand, the properties of resulting anthocyanin powders were analyzed from different aspects. Although there were some differences in bulk density, particle size and glass transition temperature among encapsulated powders using different formulations, all the samples exhibited similar moisture content, water activity, color property and crystallinity. More importantly, encapsulation using resulting optimum formulations was effective to protect blueberry anthocyanins against degradation during heating.

The pentafluorophenyl stationary phase shows a unique separation efficiency for performing fast chromatography determination of highbush blueberry anthocyanins

A high-performance liquid chromatography method using an alternative pentafluorophenyl (PFP) core-shell stationary phase has been developed and used for rapid separation of 23 anthocyanins in a highbush blueberry Bluehaven cultivar. A high efficiency of separation of anthocyanins was achieved in the core-shell column Kinetex PFP, 150×4.6mm (particle size 2.6µm) with a 5×4.6mm precolumn, using a simple linear gradient elution with a mobile phase of acetonitrile and a water solution of 2% formic acid at a flow rate of 1.0ml/min and at a temperature of 50°C. The detection wavelength was set at 520nm for detection of all anthocyanins. The homogenized blueberry sample (Bluehaven cultivar) was extracted using pure methanol with 1.3% formic acid using an ultrasound bath for 20min and then filtrated. A 5-µL sample volume was directly injected into the HPLC system. The developed method showed an efficient separation of 23 anthocyanins in a total runtime of 21min. The potential of the pentafluorophenyl phase for efficient separation was demonstrated on a wide range of anthocyanins varying in glycosylation and acylation patterns found in highbush blueberries. The fluorinated stationary phase showed an alternative and complementary separation approach providing unique aromatic and polar selectivity in comparison with common C-18 phases.

Antiproliferative and proapoptotic activities of anthocyanin and anthocyanidin extracts from blueberry fruits on B16-F10 melanoma cells

ABSTRACTBackground: Anthocyanins have been proven to affect multiple cancer-associated processes in different cancer cell lines. However, relatively few studies have investigated the effects of blueberry anthocyanins on metastatic melanoma. Thus, this study focuses on evaluating the chemopreventive potential of blueberry anthocyanins and their aglycones (anthocyanidins) in B16-F10 melanoma cells.Methods: Blueberry anthocyanin and anthocyanidin extracts were prepared mainly by combined chromatography techniques. Their antiproliferative and proapoptotic effects on B16-F10 cells were evaluated by MTT assay, calcein acetoxymethyl ester/propidium iodide (calcein-AM/PI) staining, and flow cytometry of the cell cycle and apoptosis.Results: The MTT and calcein-AM/PI staining results showed that both anthocyanin (purity of 62.5%) and anthocyanidin (75.1%) extracts could significantly inhibit the viability and proliferation of B16-F10 cells in a dose-dependent manner, while anthocyanidin extracts exhibited significantly higher (p < 0.05) cytotoxicity than anthocyanin extracts. Furthermore, anthocyanin and anthocyanidin extracts blocked cell cycle procession at the G0/G1 phase below 400 and 200 μg/mL, and induced early apoptosis below 400 and 300 μg/mL, respectively.Conclusions: These data suggest that both anthocyanin and anthocyanidin extracts inhibit the proliferation and trigger the apoptosis of B16-F10 cells, and anthocyanidin extracts may be a more promising candidate in preventing metastatic melanoma than anthocyanin extracts.

Human anthocyanin bioavailability: effect of intake duration and dosing.

While in vitro and animal evidence supports a role for anthocyanins in human health, future opportunities in berry health benefits will rest upon evidence from clinical intervention trials. Because little is known about the behaviour of anthocyanins during long term intake in humans, several clinical design factors were examined. Urine from volunteers (n = 17) who consumed blueberry juice daily was analysed using LC-MS/MS for predicted flavonoid-based products of anthocyanins in relation to a 5-day anthocyanin-free run-in, 28 days of blueberry juice intake, a 7-day washout and two dosing regimens. Total and parent anthocyanin content in urine varied 10-fold among the 17 participants. A high 24-0 h total anthocyanin excretion was associated with high anthocyanin retention (i.e. 0 h, before blueberry juice intake). Total anthocyanin excretion was not different before and after up to 7 days of washout indicative of a slow release of anthocyanins. Urinary excretion of anthocyanins declined during the 36-day study. The 24-0 h excretion was greater for total anthocyanins but not for parent anthocyanins when daily blueberry juice was taken all at once rather than as ⅓ doses taken thrice daily. However parent anthocyanins were retained better (higher 0 h) with 1× dosing. These findings could aid in the design of clinical research on anthocyanins and health.