Anthocyanin Antioxidant Research Articles

An Anthocyanin-Rich Extract of Acai (Euterpe precatoria Mart.) Increases Stress Resistance and Retards Aging-Related Markers in Caenorhabditis elegans.

Acai fruits (Euterpe precatoria) are rich in antioxidant anthocyanins. Acai consumption is believed to have many health benefits; however, relevant detailed scientific investigations are limited. The current study aimed to investigate an anthocyanin-rich extract from E. precatoria fruits (AE) with regard to its antioxidant and antiaging properties using the model organism Caenorhabditis elegans. AE can protect the worms against oxidative stress and can ameliorate accumulation of reactive oxygen species in vivo. The expression of stress-response genes, such as sod-3::GFP, was upregulated while hsp-16::GFP was down-regulated after AE treatment. Studies with DAF-16/FOXO mutants indicated that some of the antioxidant effects are mediated by this transcription factor. AE can modulate the development of age-related markers, such as pharyngeal pumping. Despite the apparent antioxidant activity, no lifespan-prolonging effect was observed.

Influence of planting time and fruit maturity stage on antioxidant activity, phenols and anthocyanin contents in sweet pepper

The field experiment was carried out to determine the effect of planting time and fruit maturity stage of antioxidant activity. The results show that the fruit maturity stage and planting time significantly (P<0.005) influenced the antioxidant activity in sweet pepper. Each planting time presented significant differences in antioxidant compounds depending on the maturity stage, but we could recommend 2nd week of May as the optimal planting time if fruits are to be harvested for greater antioxidant activity for CUPRAC, phenols and anthocyanin, while FRAP contents were recorded second highest during this period. From the nutritional point of view, the red state was the most appropriate state of maturation, since red peppers had the highest levels CUPRAC, FRAP and anthocyanin. The concentration of these phytochemicals except total phenolic contents increased as the peppers reached at mature red stage. These results will definitely be prove useful to sweet pepper growers, especially in their selection of planting time and stage of fruit maturity with high antioxidant activity so as to meet the increasing consumer demand for healthy food.

Effects of Anthocyanins on CAG Repeat Instability and Behaviour in Huntington's Disease R6/1 Mice.

Background: Huntington’s disease (HD) is a progressive neurodegenerative disorder caused by CAG repeat expansions in the HTT gene. Somatic repeat expansion in the R6/1 mouse model of HD depends on mismatch repair and is worsened by base excision repair initiated by the 7,8-dihydroxy-8-oxoguanine-DNA glycosylase (Ogg1) or Nei-like 1 (Neil1). Ogg1 and Neil1 repairs common oxidative lesions.Methods: We investigated whether anthocyanin antioxidants added daily to the drinking water could affect CAG repeat instability in several organs and behaviour in R6/1 HD mice. In addition, anthocyanin-treated and untreated R6/1 HD mice at 22 weeks of age were tested in the open field test and on the rotarod.Results: Anthocyanin-treated R6/1 HD mice showed reduced instability index in the ears and in the cortex compared to untreated R6/1 mice, and no difference in liver and kidney. There were no significant differences in any of the parameters tested in the behavioural tests among anthocyanin-treated and untreated R6/1 HD mice.Conclusions: Our results indicate that continuous anthocyanin-treatment may have modest effects on CAG repeat instability in the ears and the cortex of R6/1 mice. More studies are required to investigate if anthocyanin-treatment could affect behaviour earlier in the disease course.

An analytical pipeline to compare and characterise the anthocyanin antioxidant activities of purple sweet potato cultivars

Purple sweet potato (Ipomoea batatas L.) is rich in anthocyanin pigments, which are valuable constituents of the human diet. Techniques to identify and quantify anthocyanins and their antioxidant potential are desirable for cultivar selection and breeding. In this study, we performed a quantitative and qualitative chemical analysis of 30 purple sweet potato (PSP) cultivars, using various assays to measure reducing power radical-scavenging activities, and linoleic acid autoxidation inhibition activity. Grey relational analysis (GRA) was applied to establish relationships between the antioxidant activities and the chemical fingerprints, in order to identify key bioactive compounds. The results indicated that four peonidin-based anthocyanins and three cyanidin-based anthocyanins make significant contributions to antioxidant activity. We conclude that the analytical pipeline described here represents an effective method to evaluate the antioxidant potential of, and the contributing compounds present in, PSP cultivars. This approach may be used to guide future breeding strategies.

Red-fleshed Apples: Old Autochthonous Fruits as a Novel Source of Anthocyanin Antioxidants.

In order to promote breeding programs and a full reintroduction into production of two local red-fleshed apple varieties grown in Bekran and Bastam (Iran), the evaluation of their antioxidant properties was of interest. LC-MS(n) based metabolic fingerprinting analyses were applied to investigate the anthocyanin content of both peel and flesh components of the fruits. Cyanidin-3-O-hexoside isomers were present in both 'Bekran' and 'Bastam' apples, whereas 'Bekran' apple was a valuable source of anthocyanin rutinose derivatives. Employing DPPH(•), ABTS(•+), and ORAC methods, the antiradical efficacy was evaluated. The ability of the investigated fruit components to scavenge OH(•), and O(2) (•-) reactive species was also assessed. ID(50) values highlighted the massive antioxidant response of 'Bekran' peel component, able to counteract by 50 % OH(•), and O(2) (•-) at 130.3 and 91.6 μg/mL, respectively. The cytoprotective screening towards HeLa, HepG2, A549, SH-5YSY, and SK-N-BE(2)-C cell lines evidenced that the investigated Iranian red-fleshed apple fruits were able to exert a significant antioxidant response in hydrogen peroxide oxidized cell systems. Data collected suggested that the revaluation of 'Bekran' and 'Bastam' apple cultivars could represent a precious source of antioxidant compounds whose dietary intake could improve the human well-being reducing risks of free radical related chronic and degenerative diseases.

Controlled release of anthocyanins from oxidized konjac glucomannan microspheres stabilized by chitosan oligosaccharides

A novel oxidized konjac glucomannan (OKGM) microsphere system was developed to protect and targeted deliver the sensitive antioxidant–anthocyanins into intestine. The microspheres were made of oxidized konjac glucomannan, which was cross-linked by Fe3+ via emulsification method. The absorption of anthocyanins was driven by the electrostatic interaction between the negatively charged OKGM microspheres and positively charged anthocyanins. CLSM images showed that anthocyanins distributed homogenously through the OKGM microspheres. The absorption and release behavior of anthocyanins on OKGM microspheres were determined as a function of pH and salt concentration. A maximum absorption capacity was obtained at pH 3 and low salt concentration. However, anthocyanins were released significantly at simulated stomach conditions due to fast degradation of OKGM microspheres. An extra positively charged chitosan oligosaccharides (COS) layer was applied on OKGM microspheres to prevent H+ ions permeating into microspheres under stomach condition. COS oligomers were cross-linked with glutaraldehyde to further strengthen the OKGM microspheres' structure. Finally, glutaraldehyde cross-linked COS stabilized OKGM microspheres became stable against H+ ions in simulated stomach condition, therefore OKGM microspheres can prevent an early release of the anthocyanins in stomach condition and achieve a sustained released in the intestinal condition. The in vitro release experiments revealed that the OKGM microspheres had a potential as a carrier of targeted delivery of bioactive compounds in the intestine.

Antioxidant activity, anthocyanins and organic acids content of grape juices produced in Southwest of Minas Gerais, Brazil

Phenolic compounds and anthocyanins content in grape juices varies in the cultivar, ripening and climate characteristics. The objective of this work was to characterize and evaluate antioxidant activity of grape juices produced in southwestern Minas Gerais. Grapes were harvested, sanitized and the juices from cultivars 'Bordô', 'Isabel Precoce', 'BRS Violeta' and 'BRS Rúbea' were produced in artisanal equipment by steam extraction and stored for 120 days. The following analyzes were performed during storage: color (L *), pH, soluble solids, titratable acidity, anthocyanins, antioxidant activity (DPPH and β-caroteno/linoleic acid), total phenolics, vitamin C and organic acids. Among the cultivars evaluated, the consumption of grape juice from cultivar 'BRS Violeta' is suggested due to its higher content of vitamin C, antioxidant activity, total phenolics, anthocyanins, and also due to a better physicochemical characteristic showed, when compared to the juices of the other cultivars.

The influence of the Baltic region conditions on the accumulation of water-soluble antioxidants in plants

The studies of water-soluble antioxidants (anthocyanins, leukoanthocyanins, ascorbic acid, and total content of polyphenols, rutin, and water-soluble antioxidants) in higher plants of the Baltic region are reviewed. The patterns of antioxidant accumulation during ontogenetic development of wild plants and the impact of the environmental factors and technogenic pollution (petrol, car exhausts, heavy metals) are considered. The correlation between the accumulation of water-soluble antioxidants and the distance of plants from the sea coast is discussed.

Acylated anthocyanins from sprouts of Raphanus sativus cv. Sango: Isolation, structure elucidation and antioxidant activity

Little is known on structure–activity relationships of antioxidant anthocyanins. Raphanus sativus cv Sango sprouts are among the richest sources (270mg/100g fresh weight). We isolated from sprouts’ juice 9 acylated anthocyanins, including 4 new compounds. All comprise a cyanidin core bearing 3–4 glucose units, multiply acylated with malonic and phenolic acids (ferulic and sinapic). All compounds were equally effective in inhibiting the autoxidation of linoleic acid in aqueous micelles, with rate constant for trapping peroxyl radicals kinh=(3.8±0.7)×104M–1s–1 at 37°C. In acetonitrile solution kinh varied with acylation: (0.9–2.1)×105M–1s–1 at 30°C. Each molecule trapped a number n of peroxyl radicals ranging from 4 to 7. Anthocyanins bearing sinapic acid were more effective than those bearing the ferulic moiety. Under identical settings, deacylated cyanin, ferulic and sinapic acids had kinh of 0.4×105, 0.3×105 and 1.6×105M–1s–1 respectively, with n ranging 2–3. Results show the major role of acylation on antioxidant performance.

Antioxidant Properties, Degradation Kinetics and Storage Stability of Drinks Prepared From the Cooking Water of Pigmented Rice

Pigmented rice, consisting of black rice and red rice, is known to contain antioxidant compounds in its bran that tend to leach out into the water during cooking. As the rice is usually cooked in excess water which is discarded after cooking, the purpose of this study is therefore, to evaluate the rice cooking water as an antioxidant drink in terms of its antioxidant properties, storage stability and anthocyanin degradation kinetics. The results showed that the percentages of antioxidant extractability from pigmented rice into the cooking water were 88.42 and 103.26%, respectively for red rice and black rice, respectively. However, red rice drink possessed significantly (p<0.05) higher antioxidant activity than black rice drink, except for its total monomeric anthocyanin content. The drinks showed good microbiological stability throughout 12 weeks of storage when kept at 4°C, while those stored at 25°C lasted for 4 weeks. There was a significant decrease of antioxidant content, chroma and pH and increase in L value and hue angle, while less significant changes were observed for total soluble solids and viscosity of the drinks during the storage stability study. The degradation of anthocyanins in both drinks kept at different temperatures followed first-order reaction kinetics. According to the findings of this study, black rice and red rice cooking water have the potential of being new antioxidant drinks.

Development of An Intelligent System to Determine Sour Cherry's Antioxidant Activity and Anthocyanin Content During Ripening

Anthocyanin content and antioxidant activity are believed to display an array of beneficial actions on human health and well-being. This article presents an innovative time and cost economizing method to determine these important attributes of sour cherry during the ripening stage by combining image processing and artificial neural network techniques. For this purpose, six different stages of ripening were selected based on homogeneous size and color of the cherries. The measuring technique consisted of a charge coupled device camera for image acquisition, fluorescent illuminants, capture card, and MATLAB software for image analysis. DPPH and pH differential methods were used to determine antioxidant activity and anthocyanin content, respectively. Several artificial neural networks were designed, trained, and generalized with a back propagation neural network using ‘trainlm’ as a training function. Among these networks, two networks with 12-20-6-1 and 12-15-19-1 architectures had the highest correlation coefficients (R = 0.987 and R = 0.904) and the lowest values of MSE (0.027 and 0.186) for modeling anthocyanin content and antioxidant activity values, respectively, from laboratory results and the machine vision method. It was found that anthocyanin content was constantly increased during ripening stages of sour cherry, but antioxidant activity decreased during the early stages of sour cherry development but increased from the second stage.

Influence of Light on the Anthocyanins Stability and Antioxidant Activity of Black Currant (&lt;i&gt;Ribes nigrum &lt;/i&gt;L&lt;i&gt;.&lt;/i&gt;) Extract

Black currant (Ribes nigrumL.) possesses excellent antioxidant activity since it is rich in a great deal of phenolics, while its major phenolics, anthocyanins, are sensitive to light. This study investigated the anthocyanins stability and antioxidant activity of black currant extracts (BCE) stored under natural outdoor/indoor light and in the dark for 25 days. The anthocyanins content and antioxidant activity significantly decreased both in the presence and absence of light (P&lt;0.05). The degradation of anthocyanins followed first-order kinetics, and the k values in light were higher than that in the dark, which revealed that the anthocyanins were more stable in the dark. Exposure of the BCE to light accelerated the degradation of anthocyanins and the loss of antioxidant activity, while BCE stored in darkness maintained relatively higher anthocyanins content and antioxidant activity. These results suggested that the BCE rich in anthocyanins should be protected from light during storage to maintain its antioxidant activity and bioactive compounds.

Ampelographic and chemical characterization of Reggio Emilia and Modena (northern Italy) grapes for two traditional seasonings: ‘saba’ and ‘agresto’

'Saba' and 'agresto' are traditional Italian products both based on unfermented grape juices that are concentrated by heating. The former is obtained from ripe grapes and the latter from unripe grapes. In this work, we have characterized the main red-skinned (Ancellotta, Fortana, Lambrusco di Sorbara, Lambrusco grasparossa, Lambrusco salamino and Uva Tosca) and white-skinned (Lugliatica, Spergola, Trebbiano di Spagna and Trebbiano modenese) cultivars used for 'saba' and 'agresto' production, focusing on the variability expressed by ampelographic traits, physical and chemical parameters and anthocyanin profile. The cultivars examined were effectively discriminated on the basis of their different composition profile by analysis of variance and principal component analysis. In particular, a peculiar anthocyanin profile was traced by absolute and relative values for each cultivar. The identification of the main anthocyanins of some local cultivars, their chemical characterization and their ampelographic description were one of the main achievements of this work. The use of red grapes to obtain 'saba' seems more rational for the presence of higher amounts of antioxidant substances. Ancellotta showed several factors interesting for 'saba' production, such as the very high anthocyanin content, including anthocyanin antioxidants. A more detailed investigation on 'agresto' technology is required.

Effects of Anthocyanins on Active Avoidance Test of Rats Exposed to Disruption of Diurnal Rhythm

The present study was undertaken to assess the effects of the natural antioxidant anthocyanins on learning and memory of rats in experimental model of oxidative stress. Our preliminary experiments demonstrated that disruption of diurnal rhythm via exposition of rats to constant light for 14 days caused excessive generation of free radicals in their brains. It is known that free radicals impair cognitive functions. This study investigated the effects of anthocyanins on cognitive functions of rats in a shuttle-box active avoidance test. In the shuttle-box, stressed rats showed significantly increased latency time and decreased number of avoidances and escapes in the learning sessions. Rats treated with anthocyanins had increased number of avoidances and escapes and significantly decreased latency time during the learning sessions. Our results demonstrated that this model of oxidative stress impaired learning and memory of experimental rats. Moreover, chronic administration of anthocyanins (200 mg/kg orally) improved brain functions of the rats. Our data suggest that anthocyanins have a protective role on rat brain and improve cognitive functions in this model of oxidative stress.

Red chicory (Cichorium intybus L. cultivar) as a potential source of antioxidant anthocyanins for intestinal health.

Fruit- and vegetable-derived foods have become a very significant source of nutraceutical phytochemicals. Among vegetables, red chicory (Cichorium Intybus L. cultivar) has gained attention for its content of phenolic compounds, such as the anthocyanins. In this study, we evaluated the nutraceutical effects, in terms of antioxidant, cytoprotective, and antiproliferative activities, of extracts of the whole leaf or only the red part of the leaf of Treviso red chicory (a typical Italian red leafy plant) in various intestinal models, such as Caco-2 cells, differentiated in normal intestinal epithelia and undifferentiated Caco-2 cells. The results show that the whole leaf of red chicory can represent a good source of phytochemicals in terms of total phenolics and anthocyanins as well as the ability of these phytochemicals to exert antioxidant and cytoprotective effects in differentiated Caco-2 cells and antiproliferative effects in undifferentiated Caco-2 cells. Interestingly, compared to red chicory whole leaf extracts, the red part of leaf extracts had a significantly higher content of both total phenolics and anthocyanins. The same extracts effectively corresponded to an increase of antioxidant, cytoprotective, and antiproliferative activities. Taken together, these findings suggest that the red part of the leaf of Treviso red chicory with a high content of antioxidant anthocyanins could be interesting for development of new food supplements to improve intestinal health.

Anthocyanin Content and Antioxidant Activity of Different Varieties Blueberries

Fresh fruits and vegetables are rich sources of nutrients and phytochemicals for health. Thus, consumer has increased the demand for them, particularly blueberries. Two varieties of cultivated blueberries and a wild blueberry (Vaccinium uliginosumL.) were selected in order to determine their antioxidant activity as related to their anthocyanins. Anthocyanin content of different varieties of blueberries was determined by pH differential method. Anthocyanins from different varieties blueberries were assayed for their antioxidant properties in vitro systems, including inhibiting activity on lipid peroxidation, scavenging activity on hydroxyl radical, superoxide anion radical and DPPH radical. The results showed that anthocyanin content of wild blueberry was the highest and anthocyanin content of Northland blueberry was the lowest among different varieties blueberries. Blueberries anthocyanins were effective antioxidants, and there was a dose-dependent relationship between anthocyanins content and antioxidant activity. The overall antioxidant capacity ranked on the order of Blomidon blueberry&gt;wild blueberry&gt;Northland blueberry. The result also showed that antioxidant property was not only correlated with anthocyanins content but also related to their composition and structure. Blueberries anthocyanins was a rich source of natural antioxidant and potential used as a food additive.

Chondroitin sulfate based nanocomplex for enhancing the stability and activity of anthocyanin

To improve the structural stability of the potent antioxidant anthocyanin (ATC), a nanocomplex was fabricated from intermolecular stacking between chondroitin sulfate (CS) and ATC using a simple complexing method in water, without inputting high energy or an organic solvent. The physicochemical properties of the nanocomplex were evaluated at various feed weight ratios of CS/ATC. The most stable nanocomplex was obtained at a CS/ATC weight ratio of 10/1 (WR10). The ATC loading content and loading efficiency were 6.3 and 99%, respectively. Its diameter was approximately 300nm with unimodal size distribution. The intermolecular stacking state of WR10 was maintained up to 1μg/ml of ATC, whereas an intermolecular stacking state formed by ATC alone was easily dissociated below 16μg/ml of ATC. The structural stability of ATC in WR10 was 8 times higher than that of free ATC at 37°C. Moreover, the complex effectively protected the ATC degradation by hydroxyl molecules under high pH (above 9) conditions. Finally, cancer cell growth suppression activity was measured to determine the in vitro free radical scavenger ability of ATC. The WR10 strongly suppressed the Hela cell growth compared with ATC alone. Therefore, we conclude that the CS/ATC nanocomplex has a potential for use as a carrier for stable antioxidants or water-soluble drugs via intermolecular stacking. These nanocomplexes would prove useful for applications in the food and pharmaceutical industries.

Black rice extract extends the lifespan of fruit flies

Black rice is rich in anthocyanin antioxidants. The present study investigated the lifespan-prolonging activity of black rice extracts (BREs) and its effect on gene expressions of CuZnSOD (SOD1), MnSOD (SOD2), catalase (CAT), methuselah (Mth) and Rpn11 involved in the antioxidant system and ageing of fruit flies. The OR wild type fly was maintained on a control diet or two experimental diets containing 10 mg ml(-1) BRE (BRE10) or 30 mg ml(-1) BRE (BRE30). Results demonstrated that BRE30 could prolong the mean lifespan of fruit flies by 14%, accompanied with up-regulation of mRNA SOD1, SOD2, CAT and Rpn11, and with down-regulation of Mth. It was also found that BRE30 could attenuate the paraquat-induced neurodegeneration in OR wild type flies accompanied by up-regulation of SOD1, SOD2, CAT and Rpn11. In addition, BRE30 supplementation increased the survival time of OR wild type flies and Alzheimer transgenic flies Aβ42 33769 with chronic exposure to paraquat. It was concluded that BREs could extend the lifespan of fruit flies, most likely by regulating the genes of SOD1, SOD2, CAT, Mth and Rpn11 at the transcriptional level.

Characterization of Antioxidant Capacity from Fruits with Distinct Anthocyanin Biosynthetic Pathways

The antioxidant capacity of individual anthocyanins is well established. Less information is available however, about the relative contribution to which specific anthocyanins in a complex mixture affect total antioxidant capacity in different soft fruit sources; especially those that share a similar pathway for anthocyanin synthesis. The objectives of this work were to compare the antioxidant capacity of two different soft fruits, blackcurrant and grape, which share similarities in anthocyanin biosynthetic pathways but are composed of distinctly different anthocyanin profiles. Anthocyanin composition profiles of grape and blackcurrant were characterized by High Performance Liquid Chromatography/Mass Spectrometry (HPLC). ORAC (Oxygen Radical Absorbance Capacity) and ABTS (2,2’-azinobis 3-ethylbenzothiazoline- 6-sulfonic acid) assays were used for antioxidant activity quantification. An anthocyanin antioxidant capacity index (AACI) was derived from the product of antioxidant (ORAC) activity for each of major anthocyanins present in blackcurrant and grape, and the sum of anthocyanins recovered from purified fruit extracts to determine the extent that the total antioxidant activity derived from different anthocyanin combinations. Blackcurrant contained four predominant anthocyanins, cyanidin3-glucoside (Cy3G), delphinidin3-glucoside (Dp3G), cyanidin3-rutinoside (Cy3R), and delphinidin3- rutinoside (Dp3R). Major anthocyanins found in grape were malvidin3-glucoside (Mv3G), Dp3G, Cy3G, petunidin3-glucoside (Pt3G), and peonidin3-glucoside (Pn3G). A greater (p<0.05) total antioxidant capacity existed for blackcurrant compared to grape when measured by ORAC and ABTS methods. An antioxidant synergy was confirmed for blackcurrant and wind grape thus indicating that this phenomenon is a factor for characterizing total antioxidant activity in both blackcurrant and wine grape.

The traditional ayurvedic medicine, Eugenia jambolana (Jamun fruit), decreases liver inflammation, injury and fibrosis during cholestasis

Cholestasis is a common disease of the liver. Chronic cholestasis eventually leads to hepatic cirrhosis and fibrosis, and rodent chronic cholestasis models are used to study aspects of fibrosis and cirrhosis. Cholestasis-induced liver injury and fibrosis are associated with increased oxidative stress and inflammation. Few pharmacological therapies exist for treatment of cholestasis or cirrhosis, but it is known that humans with better nutritional intake are less likely to develop certain types of cirrhosis. Eugenia jambolana (Jamun) is a tropical berry fruit rich in antioxidant anthocyanin compounds. As anthocyanins decrease cellular lipid peroxidation and oxidative stress, it was hypothesized that Jamun fruit extract (JFE) administration could protect against cholestatic liver injury and inflammation in mice. Starting 24 h after sham or bile-duct ligation (BDL) surgery, male C57Bl/6 mice were administered vehicle or JFE (100 mg/kg, po) for 10 days. Mice that underwent BDL had elevated serum ALT levels, which were reduced to 60% by JFE treatment. Likewise, BDL caused hepatic inflammation, macrophage infiltration, fibrosis and necrosis, all of which were largely improved by JFE. Interestingly, hepatoprotection was observed in JFE-treated BDL mice, despite suppressed transporter expression and increased hepatic bile acid concentrations. Jamun fruit phytochemicals decreased hepatic inflammation and oxidative stress, and protected against hepatocellular injury in mice. Jamun warrants further investigation as a potential antioxidant/anti-inflammatory therapy not only to treat cholestasis but also other liver diseases with an inflammatory component.