Blueberry Anthocyanins Research Articles

Mathematical Modeling of the Anthocyanins Adsorption/Desorption from Blueberries on Amberlite FPX-66 Resin in A Fixed Bed Column

The objective of the present study was to predict column design parameters using mathematical models such as bed depth service time (BDST) and the empty bed residence time (EBRT). The dynamic adsorption/desorption of anthocyanins from blueberry water extracts was conducted on Amberlite FPX-66 resin in a fixed bed column system. Blueberry anthocyanins were extracted with acidified hot water (90 °C) utilizing high power ultrasound. Breakthrough curves were obtained at different bed depths (5, 7.5, 10, 12.5 and 15 cm) and constant flow rate of 4.0 mL/min. Increase in bed height increased both the breakpoint and exhaustion point of the FPX-66 resin. The experimental data fitted well to BDST model at 5% of the breakthrough curve (R2 = 0.9864). The EBRT was in the range of 3.75–10.25 min at different bed depths. In addition, desorption of anthocyanins was studied at different ethanol concentrations and sigmoid equation was applied to obtain maximum recovery rates. Practical Applications Anthocyanins are antioxidant flavonoids in blueberries. They are responsible for the blue color of the berries and are known to promote better health by preventing chronic diseases. A concentrated anthocyanin extract from blueberries has the potential to be used as dietary supplement, natural colorant and functional food ingredient. This present study optimized resin adsorption method to concentrate polyphenols and remove sugars using mathematical models. Optimization of the column design parameters can be used in designing a pilot/industrial scale column for the separation and concentration of anthocyanins from blueberries.

Blueberry anthocyanins ameliorate radiation-induced lung injury through the protein kinase RNA-activated pathway

The purpose of this study was to explore the effect of blueberry anthocyanins (BA) on radiation-induced lung injury and investigate the mechanism of action. Seven days after BA(20 and 80 mg/kg/d)administration, 6 weeks old male Sprague–Dawley rats rats were irradiated by LEKTA precise linear accelerator at a single dose of 20 Gy only once. and the rats were continuously treated with BA for 4 weeks. Moreover, human pulmonary alveolar epithelial cells (HPAEpiC) were transfected with either control-siRNA or siRNA targeting protein kinase R (PKR). Cells were then irradiated and treated with 75 μg/mL BA for 72 h. The results showed that BA significantly ameliorated radiation-induced lung inflammation, lung collagen deposition, apoptosis and PKR expression and activation. In vitro, BA significantly protected cells from radiation-induced cell death through modulating expression of Bcl-2, Bax and Caspase-3. Suppression of PKR by siRNA resulted in ablation of BA protection on radiation-induced cell death and modulation of anti-apoptotic and pro-apoptotic proteins, as well as Caspase-3 expression. These findings suggest that BA is effective in ameliorating radiation-induced lung injury, likely through the PKR signaling pathway.

Degradation kinetics of total anthocyanins and formation of polymeric color in blueberry hydrothermodynamic (HTD) processing

Anthocyanin degradation and formation of polymeric color of blueberry puree in novel hydrothermodynamic (HTD) processing was studied. Anthocyanin degradation was non-significant in the range of temperatures from 2.5 to 80 °C, becoming significant above 80 °C (p < 0.05). Analysis of kinetic data indicated a first-order reaction for the degradation of blueberry anthocyanins with energy of activation 66.37 kJ/mol and half-lives (t1/2) of 346.6, 187.3, 123.8, 80.6 and 38.7 min at temperatures of 70, 80, 87.5, 95 and 105 °C respectively. Polymeric color formation followed zero-order kinetics, progressively increasing with temperature. Polyphenol oxidase (PPO) and peroxidase (POD) were completely deactivated at 80 °C, which can be the reason of better shelf-life stability (t1/2 = 533.2 and 216.6 days at 4 and 20 °C, respectively). The beneficial aspect of technology on anthocyanin degradation and storage stability could be attributed to unique combination of temperature-pressure regimes of HTD processing.

Berry Phenolic Compounds Increase Expression of Hepatocyte Nuclear Factor-1α (HNF-1α) in Caco-2 and Normal Colon Cells Due to High Affinities with Transcription and Dimerization Domains of HNF-1α.

Hepatocyte nuclear factor-1α (HNF-1α) is found in the kidneys, spleen, thymus, testis, skin, and throughout the digestive organs. It has been found to promote the transcription of various proteins involved in the management of type II diabetes, including dipeptidyl peptidase-IV (DPP-IV). Phenolic compounds from berries and citrus fruits are known to inhibit DPP-IV, but have not been tested for their interactions with wild-type HNF-1α. By studying the interactions of compounds from berries and citrus fruits have with HNF-1α, pre-transcriptional mechanisms that inhibit the expression of proteins such as DPP-IV may be elucidated. In this study, the interactions of berry phenolic compounds and citrus flavonoids with the dimerization and transcriptional domains of HNF-1α were characterized using the molecular docking program AutoDock Vina. The anthocyanin delphinidin-3-O-arabinoside had the highest binding affinity for the dimerization domain as a homodimer (-7.2 kcal/mol) and transcription domain (-8.3 kcal/mol) of HNF-1α. Anthocyanins and anthocyanidins had relatively higher affinities than resveratrol and citrus flavonoids for both, the transcription domain and the dimerization domain as a homodimer. The flavonoid flavone had the highest affinity for a single unit of the dimerization domain (-6.5 kcal/mol). Nuclear expression of HNF-1α was measured in Caco-2 and human normal colon cells treated with blueberry and blackberry anthocyanin extracts. All extracts tested increased significantly (P < 0.05) the nuclear expression of HNF-1α in Caco-2 cells by 85.2 to 260% compared to a control. The extracts tested increased significantly (P < 0.02) the nuclear expression of HNF-1α in normal colon cells by 48.6 to 243%. It was confirmed that delphinidin-3-O-glucoside increased by 3-fold nuclear HNF-1α expression in Caco-2 cells (P < 0.05). Anthocyanins significantly increased nuclear HNF-1α expression, suggesting that these compounds might regulate the genes HNF-1α promotes.

Gastrointestinal microbiome modulator improves glucose tolerance in overweight and obese subjects: A randomized controlled pilot trial

ObjectiveThe objective of this study was to examine the effects of a gastrointestinal microbiome modulator (GIMM) containing inulin, β-glucan, blueberry anthocyanins, and blueberry polyphenols on metabolic parameters, fecal markers of gut microbiota, and satiety. Design and methodsThirty overweight or obese individuals aged 18 to 70years, were enrolled in a randomized controlled trial. Participants consumed the test product or placebo daily for four weeks. Stool samples were collected and blood was drawn at baseline and week four for assessments of gut microbiota, satiety hormones, glucose control, and lipid measures. Subjective satiety was assessed weekly. Linear models were used to compare differences from baseline to week four. ResultsGIMM consumption improved blood glucose tolerance (p=0.008), and increased satiety (p=0.03). There were no statistically significant differences in insulin sensitivity, fecal markers of gut microbiota, plasma satiety hormones, or serum lipid concentrations between the groups. However, plasma satiety hormones and fecal short chain fatty acid concentrations increased in the test group compared to the placebo. ConclusionsGIMM consumption for four weeks, increases satiety, and improves glucose tolerance possibly through insulin-independent pathways.

Intermolecular binding of blueberry pectin-rich fractions and anthocyanin

Pectin was extracted from blueberry powder into three fractions of water soluble (WSF), chelator soluble (CSF) and sodium carbonate soluble (NSF). The fractions were incubated with cyanidin-3-glucoside (C3G), a mixture of five anthocyanidins (cyanidin, pelargonidin, malvidin, petunidin and delphinidin) or blueberry juice at pH 2.0–4.5. Free anthocyanins and bound anthocyanin–pectin mixtures were separated by ultrafiltration. WSF bound the least amount of anthocyanin at all pH values. CSF had stronger anthocyanin binding ability at pH 2.0–3.6, while NSF had stronger anthocyanin binding ability at pH 3.6–4.5. The pectin and anthocyanin binding was lowest at pH 4.5 and higher at pH 2.0–3.6. Nearly doubling C3G pigment content increased bound anthocyanin percentage by 16–23% at pH 3.6, which favored anthocyanin aromatic stacking, compared to 3–9% increase at pH 2.0. Ionic interaction between anthocyanin flavylium cations and free pectic carboxyl groups, and anthocyanin stacking may be two major mechanisms for pectin and anthocyanin binding.

Evaluation of PPARα activation by known blueberry constituents.

Anthocyanins are known to have hypolipidemic properties. It was deemed necessary to determine whether major blueberry anthocyanins and catechins are ligands for the transcription factor peroxisome proliferator activated receptor alpha isoform (PPARα), and compare activation with known PPARα agonistic constituents, pterostilbene and resveratrol. It was also considered important to investigate the effect of pterostilbene on PPARα gene expression, and relate results with hepatic mRNA PPARα expression up-regulation observed previously in hamsters fed a diet supplemented with blueberry peels extract (BBX). The anthocyanins and catechins did not activate PPARα. Only pterostilbene exhibited a dose-dependent activation of PPARα in H4IIEC3 cells. The resveratrol responses were lower than those of pterostilbene. Pterostilbene significantly and dose-dependently (at 10, 20 and 50 µmol L(-1) ) increased PPARα gene expression and the effect at 10 µmol L(-1) was greater than 100 and 200 µmol L(-1) of fenofibrate. Analysis of BBX showed levels of pterostilbene and resveratrol at 418 and 2381 ng g(-1), respectively. Anthocyanins and catechins do not appear to contribute to the up-regulation of hepatic PPARα expression observed in hamsters. While pterostilbene and resveratrol demonstrated PPARα activation, their levels in BBX do not seem to be at efficacious concentrations. These stilbenes may contribute to the up-regulation of PPARα expression by acting synergistically with each other or with other constituents in BBX.

Effect of anthocyanins from rabbit-eye blueberry (Vaccinium virgatum) on cognitive function in mice under trimethyltin-induced neurotoxicity

Extracts of rabbit-eye blueberries (Vaccinium virgatum) were investigated for in vitro neuroprotective and in vivo learning and memory effects in mice under trimethyltin (TMT)-induced neurotoxicity. Blueberry anthocyanins showed high in vitro antioxidant activities in ABTS and 2’,7’-dichlorofluorescein diacetate (DCF-DA) assays. In a cell viability assay using MTT, anthocyanins showed protective effects, and lactate dehydrogenase release into the medium was effectively inhibited. Drug-induced cognitive deficits, examined in vivo using Y-maze and passive avoidance testing, were ameliorated by the anthocyanin fraction. HPLC analysis showed that delphinidin was the predominant anthocyanin. After behavioral testing, acetylcholinesterase (AChE) activities and lipid peroxidation in the mouse brain were investigated for biochemical changes. Administration of blueberry anthocyanins reduced the level of TMT-induced memory injury via inhibition of the AChE activity and lipid peroxidation.

Retraction: Properties and stability of blueberry anthocyanin--bovine serum albumin nanoparticles.

This article corrects: Retracted: Properties and stability of blueberry anthocyanin – bovine serum albumin nanoparticles

Complex Formation of Blueberry (Vaccinium angustifolium) Anthocyanins during Freeze-Drying and Its Influence on Their Biological Activity

Biological activity of polyphenols is influenced by their uptake and is highly influenced by their interactions with the food matrix. This study evaluated the complex formation of blueberry polyphenols with fruit matrixes such as pectin and cellulose and their effect on the biological and antiproliferative properties of human colon cell lines HT-29 and CRL 1790. Free or complexed polyphenols were isolated by dialyzing aqueous or methanolic blueberry homogenates. Seven phenolic compounds and thirteen anthocyanins were identified in blueberry extracts. Blueberry extracts showed varying degrees of antioxidant and antiproliferative activities, as well as α-glucosidase activity. Fruit matrix containing cellulose and pectin, or purified polygalacturonic acid and cellulose, did not retain polyphenols and showed very low antioxidant or antiproliferative activities. These findings suggest that interactions between polyphenols and the food matrix may be more complex than a simple association and may play an important role in the bioefficacy of blueberry polyphenols.

Blueberry anthocyanins extract inhibits acrylamide-induced diverse toxicity in mice by preventing oxidative stress and cytochrome P450 2E1 activation

The intervention effects of blueberry anthocyanins extract (BAE) on the acrylamide (AA)-induced general toxicity, genotoxicity and reproductive toxicity were investigated in a mice model. Compared to the AA group, BAE restored the AA-induced alteration in haematology and serum chemistry, markedly decreased the DNA damage in lymphocyte and liver cells, as well as micronucleus formation in bone marrow cell. Meanwhile, BAE improved sperm motility levels and decreased abnormal sperm rate. Furthermore, BAE inhibited the AA-induced ROS accumulation and glutathione (GSH) depletion, ameliorated the activities of glutathione peroxidase (GPx) and glutathione-S-transferase (GST), improved the protein expression of GPx, GST and gamma-glutamyl cysteine synthase (γ-GCS), and inhibited the cytochrome P4502E1 (CYP2E1) protein expression. Thus, the intervention mechanism of BAE on the AA-induced toxicity possibly attributed to the prevention of AA-induced oxidative stress and CYP2E1 activation. BAE would have potential application for the chemoprevention of the AA toxicity as a nutraceutical or a dietary supplement.

The chemoprotection of a blueberry anthocyanin extract against the acrylamide-induced oxidative stress in mitochondria: unequivocal evidence in mice liver.

Acrylamide (AA) is one of the most important contaminants occurring in heated food products. Accumulating evidence indicates that AA-induced toxicity is associated with oxidative stress and long-term exposure to AA induced mitochondria collapse and finally leads to apoptosis. Whereas anthocyanins are natural antioxidants and have a strong ability to reduce oxidative damage in vivo. This study investigates the protection of a blueberry anthocyanin extract (BAE) against AA-induced mitochondrial oxidative stress in mice models. The activities of electron transport chain complexes, oxidative status, and the structure and function of mitochondria were measured. Results showed that pretreatment with BAE markedly inhibited reactive oxygen species (ROS) formation, and prevented the successive events associated with the mitochondrial damage and dysfunction, including recovered activities of electron transport chain, ATPase and superoxide dismutase, ameliorated depolarization of mitochondrial membrane potential and membrane lipid peroxidation, reduced release of cytochrome c and protection of mitochondria against swelling. In a word, mitochondria are a key target at the organelle level for the protective effect of BAE against AA toxicity. These results will be helpful to provide new clues for a better understanding of the AA toxicity intervention mechanism and for exploring effective dietary constituents for intervention of AA toxicity.

Blueberry effects on dark vision and recovery after photobleaching: placebo-controlled crossover studies.

Clinical evidence for anthocyanin benefits in night vision is controversial. This paper presents two human trials investigating blueberry anthocyanin effects on dark adaptation, functional night vision, and vision recovery after retinal photobleaching. One trial, S2 (n = 72), employed a 3 week intervention and a 3 week washout, two anthocyanin doses (271 and 7.11 mg cyanidin 3-glucoside equivalents (C3g eq)), and placebo. The other trial, L1 (n = 59), employed a 12 week intervention and an 8 week washout and tested one dose (346 mg C3g eq) and placebo. In both S2 and L1 neither dark adaptation nor night vision was improved by anthocyanin intake. However, in both trials anthocyanin consumption hastened the recovery of visual acuity after photobleaching. In S2 both anthocyanin doses were effective (P = 0.014), and in L1 recovery was improved at 8 weeks (P = 0.027) and 12 weeks (P = 0.030). Although photobleaching recovery was hastened by anthocyanins, it is not known whether this improvement would have an impact on everyday vision.

Protective effect of blueberry anthocyanins in a CCL4-induced liver cell model

This study investigates the protective effects of blueberry anthocyanins against acute liver injury. Cyanidin-3-glucoside, delphinidin-3-rutinoside, and malvidin-3-galactoside, the main monomers among blueberry anthocyanins, play important roles in cell survival and in increasing the level of the main cellular antioxidant. Results of the cell proliferation assay showed that different concentrations of blueberry anthocyanins protected the human embryonic-liver L-02 cells against CCl4-induced injury in a dose-dependent manner. After 48 h of incubation, the anthocyanins protected the human embryonic-liver L-02 cells, with IC50 of 6.2 × mg/L. Cell-clone formation inhibition assay demonstrated that cell clones increased with increased concentration of anthocyanins. Propidium iodide (PI) staining and DNA ploidy analysis showed that anthocyanins can decrease cell cycle in the G1 phase, which leads to a reduced percentage of hypodiploid cells, in a dose-dependent manner. Moreover, annexin V-FITC/PI staining analysis showed a dose-dependent effect of anthocyanins on late-apoptotic and necrotic cells. Western blot assay showed a gradual decrease in caspase-3 protein expression levels with the increase in anthocyanin concentration. These findings support the protective effects of blueberry extract against acute liver injury.

Blueberry anthocyanins ameliorate cyclophosphamide-induced liver damage in rats by reducing inflammation and apoptosis

We attempted to determine whether blueberry anthocyanins (BA) would be protective against cyclophosphamide (CTX)-induced liver injury in SD rats. CTX was injected intraperitoneally into rats to induce liver toxicity. The rats were randomly divided into four groups: a control group, a CTX group, and two groups received BA at doses of 20 and 80 mg/kg/day for 7 days (i.g.), both before and after they were administered CTX. Liver histopathology, serum liver enzymatic activities, cytokines and apoptotic parameters were evaluated. The rats that were injected with CTX incurred liver injury, evidenced by histological changes and elevated serum enzymes activities; CTX led to elevated proinflammatory cytokines, and reduced anti-inflammatory cytokine; also induced apoptosis, indicated by increased Bax and TLR4, and decreased Bcl-2 expression in western blot assay, which was further confirmed by immunohistochemistry assay with anti-Bax antibody. BA had a protective effect against CTX-induced liver damage in rats.

Blueberry anthocyanins induce G2/M cell cycle arrest and apoptosis of oral cancer KB cells through down-regulation methylation of p53

Blueberries are an excellent source of dietary polyphenols such as anthocyanins and phenolic acids. In this study, we investigated the ability of anthocyanins from the wild blueberries of Inner Mongolia to suppress the growth of the oral cancer cell line KB. The blueberry anthocyanins were extracted with methanol-containing 0.1% (v/v) hydrochloric acid. Fourteen unique anthocyanins were identified using high-performance liquid chromatography-mass spectrometry (HPLC-MS). The anticancer bioactivity of the extracts on KB cells was analyzed using methylthiazolyl-tetrazolium (MTT), flow cytometry (FCM) and immunocytochemistry. It was shown that the blueberry anthocyanins suppressed the proliferation of KB cells in a dose-dependent manner, as well as induced G2/M cell cycle arrest and apoptosis of oral cancer KB cells. Immunocytochemistry analysis showed that the expression of caspase-9 and cytochrome c were obviously increased after the anthocyanins treatment. Western blot analysis also indicated that the expression of p53 was increased. Methylation-specific PCR (MSP) showed that the amount of unmethylated p53 increased, indicating that the anthocyanins can down-regulate the methylation of p53.

Inhibitory Effects of Wild Blueberry Anthocyanins and Other Flavonoids on Biomarkers of Acute and Chronic Inflammation in Vitro

Wild lowbush blueberries (Vaccinium angustifolium Ait) are a rich source of anthocyanins and other flavonoids with anti-inflammatory activities; however, their individual effects on cellular signaling remain to be elucidated. This study determined the capacity of blueberry bioactives to protect murine RAW 264.7 macrophages from lipopolysaccharide-induced inflammation. Fractionation of the crude extract (CE) into polyphenol-rich (PPR), anthocyanin-rich (ANC), and proanthocyanidin-rich (PAC) fractions and an ethyl acetate fraction (EA) revealed that PPR, ANC, and PAC components most effectively suppressed mRNA biomarkers of acute inflammation (Cox-2, iNOS, and IL-1β). Among major polyphenols found in the wild blueberries, malvidin-3-glucoside was significantly more effective than epicatechin or chlorogenic acid in reducing the expression of pro-inflammatory genes in vitro.

Stability and absorption of anthocyanins from blueberries subjected to a simulated digestion process

Numerous studies have shown that anthocyanins usually have better in vitro bioactivity than in vivo bioactivity. This may be due to physiochemical degradation during gastrointestinal digestion and their poor bioavailability in in vivo studies. Therefore, this study aims to investigate the effects of anthocyanin structure on their stability under simulated gastrointestinal digestion and to assess their absorption in the intestines using Caco-2 human intestinal cell monolayers. The results show that gastric digestion does not significant affect blueberry anthocyanins in terms of composition and antioxidative activity. However, approximately 42% of the total anthocyanin and 29% of the antioxidative activity were lost during intestinal digestion. Structural analysis indicated that fewer free hydroxyl groups and more methoxy groups in the B-ring improve anthocyanin stability. The absorption trials demonstrated that more hydrophobic anthocyanins have better absorption efficiency than more hydrophilic anthocyanins. Furthermore, the glycoside structure also determines the absorption efficiency of anthocyanins.

냉동 블루베리 분말과 검정콩 안토시아닌 혼합 파운드 케이크의 항산화 활성과 품질 특성

A study is undertaken to examine the effects of the additional frozen blueberry powder and anthocyanin powder extracted from black beans to quality attributes of pound cakes. Frozen blueberry powder and anthocyanin powder extracted from black beans are being added to the flour at a ratio of 0.5, 1.5, 2.5, and 3.5% respectively. The antioxidant activity is highly correlated with the total phenolic and total flavonoids contents of frozen blueberry powder and anthocyanin powder extracted from black beans of pound cakes, respectively (r=0.8423, p<0.001 r=0.9449, p<0.001). The quality characteristics of the specific volumes decreased significantly with increasing substitution levels of frozen blueberry powder and anthocyanin powder extracted from black beans (p<0.01). The lightness significantly decreased with increasing frozen blueberry powder and anthocyanin powder extracted from black beans of pound cakes' crusts and crumbs (p<0.01). The hardness, chewiness and gumminess tend to reduce, while the cohesiveness increase in both powders. The consumer acceptability score for 0.5~3.5% of frozen blueberry powder and anthocyanin powder extracted from black beans pound cakes ranked significantly (p<0.01) higher than those of the other groups according to taste, flavor and overall preferences. These results show that frozen blueberry powder and anthocyanin powder extracted from the black beans are a good ingredient for increasing consumer acceptability and overall healthy.

Retracted: Properties and stability of blueberry anthocyanin - bovine serum albumin nanoparticles

Since they would be easily decomposed under alkaline conditions, anthocyanins are likely to have poor oxidation stability. However, encapsulated with protein molecules, anthocyanins could be protected owing to the slowing down of the oxidation process. In this study, the characteristics of nanoparticles, formed by the interactions of anthocyanins with bovine serum albumin (BSA), and their impact on the oxidation stability of anthocyanins were investigated. Both BSA and anthocyanin-bound BSA could form self-assembled nanoparticles in phosphate buffer (pH 7.4), and the particle size of anthocyanin-bound BSA (20-25 nm) was smaller than that of BSA (35-40 nm). The ratio of BSA to anthocyanin was 1:10. The radical scavenging rates of BSA-bound anthocyanin were lower than those of the unbound anthocyanin. No significant difference was seen in the stability between the unbound and BSA-bound anthocyanin in the simulated gastric system, whereas a difference was seen in the simulated intestinal system. The amount of unbound anthocyanin decreased by 70% after 6 h, while BSA-bound anthocyanin was almost unchanged. BSA exhibited a remarkable effect on the oxidation stability of anthocyanins. BSA nanocarriers could improve the stability of anthocyanin under neutral conditions, which has great potential for applications.