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Anthocyanins: Recent Progress in Health Benefits Studies

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A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Natural Products Chemistry".

Deadline for manuscript submissions: closed (30 September 2019) | Viewed by 76886

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Special Issue Editors

Prof. Dr. Takanori Tsuda

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Guest Editor

College of Bioscience and Biotechnology, Chubu University, Kasugai, Japan
Interests: anthocyanins; curcumin; diabetes; obesity; glucagon-like peptide-1; beige cells; brown-like adipocytes

Dr. Wilhelmina Kalt

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Guest Editor

retired
Interests: anthocyanins; berries; blueberries; bioavailability; bioactivity; flavonoids; health

Special Issue Information

Dear Colleagues,

“Anthocyanins”, belonging to the group flavonoids, are plant pigments that may appear to be red or purple and are present in the form of glycosides. Efforts have been made to identify genes for anthocyanin synthesis in plants and elucidate the regulatory pathways for gene expression. In addition, stabilization and extraction processes of anthocyanins from plant sources have been developed to use in food pigments. Despite research progress in plant biochemistry and the utilization of food pigments, the role of anthocyanins as a functional food factor remains relatively less established than other flavonoids. However, anthocyanins and anthocyanin-rich berries’ health-related functions have been conducted such as anti-arteriosclerosis, anti-obesity, anti-diabetes, brain function-enhancing, and the improvement of visual and vascular functions in the last 20 years. These favorable functions are not explained by their antioxidant properties alone, and thus anthocyanins are received as functional food factors with “beyond antioxidant” functions. Also, resent studies that have been shown metabolites of anthocyanins may have a significant impact on various health benefits.

In this Special Issue, resent research advances in health benefit studies in anthocyanins including anthocyanin-rich berries and related foods in cells, animals, and humans will be invited. Studies on molecular mechanisms, absorption and metabolism, effects on intestinal flora, and epidemiology are also welcome.

Prof. Takanori Tsuda
Dr. Wilhelmina Kalt
Guest Editors

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Keywords

Anthocyanins
Berries
Flavonoids
Absorption
Metabolism
Intestinal flora
Obesity
Diabetes
Atherosclerosis
Cardiovascular disease
Brain function
Athorosclerosis

Published Papers (12 papers)

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Research

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10 pages, 813 KiB

Open AccessArticle

Effects of Blackcurrant Anthocyanin on Endothelial Function and Peripheral Temperature in Young Smokers

by Toshiko Tomisawa, Naoki Nanashima, Maiko Kitajima, Kasumi Mikami, Shizuka Takamagi, Hayato Maeda, Kayo Horie, Fu-chih Lai and Tomohiro Osanai

Molecules 2019, 24(23), 4295; https://doi.org/10.3390/molecules24234295 - 25 Nov 2019

Cited by 14 | Viewed by 3570

Abstract

Background: Blackcurrant anthocyanin (BCA) is expected to repair endothelial dysfunction, but it remains unclear whether beneficial effects are present in young healthy persons. This study examines whether supplements containing blackcurrant anthocyanin improve endothelial function and peripheral temperature in young smokers. Methods: Young, healthy male nonsmokers (N group: n = 11; mean age 22 ± 2 years) and smokers (S group: n = 13; mean age 21 ± 1 years) were enrolled. A randomized and double-blind trial was designed to compare the effects of no supplement, a supplement containing 50 mg of blackcurrant anthocyanin (supplement A), and a supplement containing 50 mg of blackcurrant anthocyanin plus vitamin E (supplement B) on flow-mediated dilatation (FMD) and skin temperature. Results: Under no supplement, FMD was unchanged during the 2 h period after smoking in the N group, whereas it was decreased during the 2 h period after smoking in the S group. Under the A supplement, FMD was decreased 1 h after smoking and returned to the baseline level 2 h after smoking in the S group. The skin temperature in the area of the foot dorsum was decreased in the S group after smoking compared with that in the N group, who did not smoke, whereas under A and B supplements, it was higher in the S group compared with that in the N group. Conclusions: BCA could attenuate the smoking-induced acute endothelial dysfunction and improve peripheral temperature in young smokers. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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20 pages, 8437 KiB

Open AccessArticle

Contribution of Berry Polyphenols to the Human Metabolome

by Preeti Chandra, Atul S. Rathore, Kristine L. Kay, Jessica L. Everhart, Peter Curtis, Britt Burton-Freeman, Aedin Cassidy and Colin D. Kay

Molecules 2019, 24(23), 4220; https://doi.org/10.3390/molecules24234220 - 20 Nov 2019

Cited by 27 | Viewed by 4302

Abstract

Diets rich in berries provide health benefits, however, the contribution of berry phytochemicals to the human metabolome is largely unknown. The present study aimed to establish the impact of berry phytochemicals on the human metabolome. A “systematic review strategy” was utilized to characterize the phytochemical composition of the berries most commonly consumed in the USA; (poly)phenols, primarily anthocyanins, comprised the majority of reported plant secondary metabolites. A reference standard library and tandem mass spectrometry (MS/MS) quantitative metabolomics methodology were developed and applied to serum/plasma samples from a blueberry and a strawberry intervention, revealing a diversity of benzoic, cinnamic, phenylacetic, 3-(phenyl)propanoic and hippuric acids, and benzyldehydes. 3-Phenylpropanoic, 2-hydroxybenzoic, and hippuric acid were highly abundant (mean > 1 µM). Few metabolites at concentrations above 100 nM changed significantly in either intervention. Significant intervention effects (p < 0.05) were observed for plasma/serum 2-hydroxybenzoic acid and hippuric acid in the blueberry intervention, and for 3-methoxyphenylacetic acid and 4-hydroxyphenylacetic acid in the strawberry intervention. However, significant within-group effects for change from baseline were prevalent, suggesting that high inter-individual variability precluded significant treatment effects. Berry consumption in general appears to cause a fluctuation in the pools of small molecule metabolites already present at baseline, rather than the appearance of unique berry-derived metabolites, which likely reflects the ubiquitous nature of (poly)phenols in the background diet. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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14 pages, 2794 KiB

Open AccessArticle

Anthocyanin-Rich Sour Cherry Extract Attenuates the Lipopolysaccharide-Induced Endothelial Inflammatory Response

by Attila Biro, Arnold Markovich, Judit Rita Homoki, Erzsébet Szőllősi, Csaba Hegedűs, Szabolcs Tarapcsák, János Lukács, László Stündl and Judit Remenyik

Molecules 2019, 24(19), 3427; https://doi.org/10.3390/molecules24193427 - 21 Sep 2019

Cited by 15 | Viewed by 4193

Abstract

The anthocyanin content of Hungarian sour cherry is remarkable based on our preliminary investigations. Nutraceutical and pharmaceutical effects of anthocyanins have been extensively studied. The objective of this work was to investigate the the effect of purified sour cherry extract using human umbilical cord vein endothelial cells (HUVECs) as the inflammatory model. HUVECs were isolated by enzymatic digestion and characterized by flow cytometry. The optimal concentration range of sour cherry extract was selected based on MTT, apoptosis, and necrosis assays. Cells were divided into three groups, incubating with M199 medium as control, or with lipopolysaccharide (LPS) or with LPS plus anthocyanin extract (ACE). The effect of sour cherry extract on oxidative stress, pro-inflammatory factors, and arachidonic pathway was investigated. An amount of 50 μg/mL ACE (ACE₅₀) was able to increase the level of glutathione and decrease the ROS, thereby improving the unbalanced redox status in inflammation. ACE₅₀ lowered pro-inflammatory cytokine levels including Interleukin-6 (IL-6), regulated on activation, normal T cell expressed and secreted (RANTES), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor alpha (TNF-α). ACE₅₀ affected the arachidonic acid pathway by reducing the LPS-induced enzyme expression (cyclooxygenase-1, cyclooxygenase-2, and prostacyclin synthase). The extract under investigation seems to have a pleiotropic effect including anti-oxidative, anti-inflammatory, hemostatic, and vasoactive effects. Our results indicate that purified sour cherry extract could reduce the LPS-induced inflammatory response, thereby improving endothelial dysfunction. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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22 pages, 4738 KiB

Open AccessArticle

Antidiabetic and Antioxidative Potential of the Blue Congo Variety of Purple Potato Extract in Streptozotocin-Induced Diabetic Rats

by Paulina Strugała, Olha Dzydzan, Iryna Brodyak, Alicja Z. Kucharska, Piotr Kuropka, Mariana Liuta, Katarzyna Kaleta-Kuratewicz, Agnieszka Przewodowska, Dorota Michałowska, Janina Gabrielska and Natalia Sybirna

Molecules 2019, 24(17), 3126; https://doi.org/10.3390/molecules24173126 - 28 Aug 2019

Cited by 44 | Viewed by 7043

Abstract

This study was designed to evaluate the effects of purple potato extract of the Blue Congo variety (PP) on diabetes and its antioxidant activities after two-week administration tostreptozotocin (STZ)-induced diabetic rats. The activities of PP were evaluated at a dose of 165 mg/kg body weight (b.w.) by estimating biochemical changes in blood plasma and through a histopathological study of kidney, muscles, and liver tissue. We evaluated the effect of treatment with extract on glucose level, glycated hemoglobin, activities of enzymatic antioxidants (including superoxide dismutase, glutathione peroxidase, and catalase), and lipid peroxidation. Moreover, we determined advanced glycation end-products (AGEs), advanced oxidation protein products (AOPPs), and the level of oxidative modified proteins (OMPs) as markers of carbonyl-oxidative stress in rats with diabetes. Using high-performance liquid chromatography, we identified five anthocyanins and six phenolic acids in the extract from Blue Congo with the dominant acylated anthocyanin as petunidin-3-p-coumaroyl-rutinoside-5-glucoside. The administration of Blue Congo extract lowered blood glucose, improved glucose tolerance, and decreased the amount of glycated hemoglobin. Furthermore, PP demonstrated an antioxidative effect, suppressed malondialdehyde levels, and restored antioxidant enzyme activities in diabetic rats. After administration of PP, we also noticed inhibition of OMP, AGE, and AOPP formation in the rats′ blood plasma. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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12 pages, 2645 KiB

Open AccessArticle

Anti-Adipogenic Effects of Delphinidin-3-O-β-Glucoside in 3T3-L1 Preadipocytes and Primary White Adipocytes

by Miey Park, Anshul Sharma and Hae-Jeung Lee

Molecules 2019, 24(10), 1848; https://doi.org/10.3390/molecules24101848 - 14 May 2019

Cited by 33 | Viewed by 4636

Abstract

Delphinidin-3-O-β-glucoside (D3G) is a health-promoting anthocyanin whose anti-obesity activity has not yet been thoroughly investigated. We examined the effects of D3G on adipogenesis and lipogenesis in 3T3-L1 adipocytes and primary white adipocytes using real-time RT-PCR and immunoblot analysis. D3G significantly inhibited the accumulation of lipids in a dose-dependent manner without displaying cytotoxicity. In the 3T3-L1 adipocytes, D3G downregulated the expression of key adipogenic and lipogenic markers, which are known as peroxisome proliferator-activated receptor gamma (PPARγ), sterol regulatory element-binding transcription factor 1 (SREBP1), CCAAT/enhancer-binding protein alpha (C/EBPα), and fatty acid synthase (FAS). Moreover, the relative protein expression of silent mating type information regulation 2 homolog 1 (SIRT1) and carnitine palmitoyltransferase-1 (CPT-1) were increased, alongside reduced lipid levels and the presence of several small lipid droplets. Furthermore, D3G increased the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), which suggests that D3G may play a role in AMPK and ACC activation in adipocytes. Our data indicate that D3G attenuates adipogenesis and promotes lipid metabolism by activating AMPK-mediated signaling, and, hence, could have a therapeutic role in the management and treatment of obesity. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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12 pages, 5229 KiB

Open AccessArticle

Anthocyanin Encapsulated by Ferulic Acid-Grafted-Maltodextrin (FA-g-MD) Microcapsules Potentially Improved its Free Radical Scavenging Capabilities Against H₂O₂-Induced Oxidative Stress

by Yi Ma, Yunhui Feng, Wanling Zeng and Huibo Luo

Molecules 2019, 24(8), 1596; https://doi.org/10.3390/molecules24081596 - 23 Apr 2019

Cited by 13 | Viewed by 3130

Abstract

This study aimed to investigate the antioxidant activity and release behavior of anthocyanin (ANC) loaded within FA-g-MD wall (ANC-FA-g-MD microcapsule) in vitro. The microencapsulation of ANC was prepared by spray drying and displayed a biphasic release profile. The combination of ANC and FA-g-MD (0.0625–1 mg/mL) showed a higher antioxidant activity than that of both individuals. A possible intermolecular interaction between ANC and FA-g-MD was studied by UV-vis spectra. Intracellular reactive oxygen species (ROS), 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) test, and protein expression of quinone oxidoreductase 1(NQO1), glutathione reductase (GSR) and γ-glutamate cysteine ligase catalytic subunit (γ-GCLC) were measured through human colon cancer cells (HT-29). After a 24-hour incubation of the HT-29, the combinations (0–60 μg/mL) exhibited a high potential to diminish the ROS level. And the distinct upregulated expressions of GCLC and NQO1 of HT-29 were detected after treatment with combinations compared to those of single ones. These results suggested that the ANC-FA-g-MD microcapsules exerts enhanced antioxidant effect with capability of the modulation of GCLC and NQO1. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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11 pages, 4658 KiB

Open AccessArticle

Blackcurrant Extract with Phytoestrogen Activity Alleviates Hair Loss in Ovariectomized Rats

by Naoki Nanashima and Kayo Horie

Molecules 2019, 24(7), 1272; https://doi.org/10.3390/molecules24071272 - 01 Apr 2019

Cited by 9 | Viewed by 4897

Abstract

Ancocyanin-rich blackcurrant extract (BCE) has phytoestrogen activity; however, its effect on hair follicles is unknown. Additionally, hair loss is known to occur during menopause in women owing to decreased estrogen secretion. This study examined whether BCE alleviated female pattern hair loss using a rat model. RNA was extracted and analyzed using a microarray and ingenuity pathway analysis. A quantitative polymerase chain reaction revealed that 1 μg/mL BCE altered many genes downstream of beta-estradiol in human hair dermal papilla cells. Additionally, the expression of the hair follicle stem cell marker keratin 19 was greatly enhanced. In a menopause model, ovariectomized rats were fed a diet containing 3% BCE for three months. An analysis of the number of hair shafts revealed that BCE increased the number of hairs by 0.5 hairs/follicular unit. Moreover, immunostaining revealed that the expression of Ki67 also increased by 19%. Furthermore, fluorescent immunostaining showed that the expression of other stem cell markers, including keratin 15, CD34, and keratin 19, was induced in rat hair follicular cells. In conclusion, these findings suggest that BCE has phytoestrogen activity in hair follicles and contributes to the alleviation of hair loss in a menopausal model in rats. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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11 pages, 1518 KiB

Open AccessArticle

Phytoestrogenic Effects of Blackcurrant Anthocyanins Increased Endothelial Nitric Oxide Synthase (eNOS) Expression in Human Endothelial Cells and Ovariectomized Rats

by Kayo Horie, Naoki Nanashima and Hayato Maeda

Molecules 2019, 24(7), 1259; https://doi.org/10.3390/molecules24071259 - 31 Mar 2019

Cited by 23 | Viewed by 4366

Abstract

Phytoestrogens are plant-derived chemicals that are found in many foods and have estrogenic activity. We previously showed that blackcurrant extract (BCE) and anthocyanins have phytoestrogenic activity mediated via estrogen receptors (ERs), and anthocyanins may improve vascular function. BCE contains high levels of anthocyanins, but their health-promoting effects are unclear. This study examined the effects of BCE on the regulation of endothelial nitric oxide synthase (eNOS) expression and nitric oxide (NO) synthesis in human endothelial cells as key regulators in cardiovascular disease. The results showed that eNOS mRNA levels were significantly upregulated in BCE- or anthocyanin-treated human vascular endothelial cells but decreased in cells treated with fulvestrant, an ER antagonist. These results corresponded with NO levels, suggesting that BCE and anthocyanin may regulate NO synthesis via eNOS expression. Thus, the phytoestrogenic effects exerted by BCE via ERs influenced eNOS mRNA expression and NO synthesis. In vivo, we investigated whether anthocyanin-rich BCE upregulated eNOS protein expression in ovariectomized (OVX) rats, a widely used animal model of menopause. Our results showed that anthocyanin-rich BCE significantly upregulated eNOS mRNA levels and NO synthesis through phytoestrogenic activity and therefore promoted blood vessel health in OVX rats as a postmenopausal model. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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Review

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15 pages, 2280 KiB

Open AccessReview

Anthocyanins Potentially Contribute to Defense against Alzheimer’s Disease

by Mohammad Afzal, Amina Redha and Redha AlHasan

Molecules 2019, 24(23), 4255; https://doi.org/10.3390/molecules24234255 - 22 Nov 2019

Cited by 41 | Viewed by 12854

Abstract

Anthocyanins (ANTs) are plant pigments that belong to a flavanol class of polyphenols and have diverse pharmacological properties. These compounds are primarily found in fruits and vegetables, with an average daily intake of 180 mgd⁻¹ of these compounds in the developed world. ANTs are potent antioxidants that might regulate the free radical-mediated generation of amyloid peptides (Abeta-amyloids) in the brain, which causes Alzheimer’s disease (AD). This study presents a literature review of ANTs from different berries and their potential therapeutic value, with particular emphasis on neurodegenerative AD, which owing to oxidative stress. This review also highlights reactive oxygen species (ROS) generation through energy metabolism, nitrogen reactive species, the role of transition metals in generating ROS, and the radical-quenching mechanisms of natural antioxidants, including ANTs. The current status of the bioavailability, solubility, and structure activity relationship of ANTs is discussed herein. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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18 pages, 911 KiB

Open AccessFeature PaperReview

Anthocyanins and Their C₆-C₃-C₆ Metabolites in Humans and Animals

by Wilhelmina Kalt

Molecules 2019, 24(22), 4024; https://doi.org/10.3390/molecules24224024 - 07 Nov 2019

Cited by 40 | Viewed by 5728

Abstract

Research on the bioavailability of anthocyanins has focused, historically, on the non-flavonoid (C₆-C_n) products that arise from anthocyanins in vivo. However, this review focuses on the products of anthocyanins that still possess the flavonoid structure (C₆-C₃-C₆). Described herein are aspects of the in vivo pool of C₆-C₃-C₆ anthocyanin-derived intermediates. Properties related to molecular size, shape, and polarity conveyed by six major anthocyanidin structures are discussed. The presence of a glycoside or not, and a variety of possible phase 2 conjugates, gives rise to a chemically diverse pool of C₆-C₃-C₆ intermediates. Chemical properties influence the in vivo stability of anthocyanin-derived products, as well as their suitability as a substrate for xenobiotic conjugation and transport, and their association with the biomatrix. The flavonoid structure is associated with bioactivity and the particular properties of these C₆-C₃-C₆ products of anthocyanins determines their deposition in the body, which may influence in vivo processes and ultimately health outcomes. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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57 pages, 2455 KiB

Open AccessReview

Black Chokeberry Aronia Melanocarpa L.—A Qualitative Composition, Phenolic Profile and Antioxidant Potential

by Andrzej Sidor and Anna Gramza-Michałowska

Molecules 2019, 24(20), 3710; https://doi.org/10.3390/molecules24203710 - 15 Oct 2019

Cited by 105 | Viewed by 10680

Abstract

Black chokeberry (Aronia melnocarpa) is a source of many bioactive compounds with a wide spectrum of health-promoting properties. Fresh, unprocessed chokeberry fruits are rarely consumed due to their astringent taste, but they are used in the food industry for the production of juices, nectars, syrups, jams, preserves, wines, tinctures, fruit desserts, jellies, fruit teas and dietary supplements. Polyphenols are biofactors that determine the high bioactivity of chokeberries, some of the richest sources of polyphenols, which include anthocyanins, proanthocyanidins, flavonols, flavanols, proanthocyanidins, and phenolic acids. Chokeberry fruit and products have great antioxidant and health-promoting potential as they reduce the occurrence of free radicals. This publication reviewed the scientific research regarding the phenolic compounds and the antioxidant potential of chokeberry fruits, products and isolated compounds. These findings may be crucial in future research concerning chokeberry based functional food products. Chokeberry fruits can be considered as promising component of designed food with enhanced antioxidant potential. However, like other plants and medicinal products of natural origin, black chokeberry requires extensive studies to determine its antioxidant potential, safety and mechanisms of action. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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18 pages, 3112 KiB

Open AccessReview

Therapeutic Effects of Anthocyanins for Vision and Eye Health

by Yuri Nomi, Keiko Iwasaki-Kurashige and Hitoshi Matsumoto

Molecules 2019, 24(18), 3311; https://doi.org/10.3390/molecules24183311 - 11 Sep 2019

Cited by 68 | Viewed by 10348

Abstract

Anthocyanin (AC) is widely used as supplement of eye health in Europe and in East Asia. In this review, I describe AC effects to clarify the mechanism is important in order to understand the effects of AC on vision health. The bioavailability of AC is quite low but, reported as intact form and many kinds of metabolite. And AC passes through the blood-aqueous fluid barrier and blood-retinal barrier. In vitro study, AC had a relaxing effect on ciliary muscle which is important to treat both myopia and glaucoma. And AC stimulate the regeneration of rhodopsin in frog rod outer segment. Furthermore, AC could inhibit the axial length and ocular length elongation in a negative lens-induced chick myopia model. In addition, we summarized clinical studies of AC intake improved dark adaptation and transient myopic shift and the improvement on retinal blood circulation in normal tension glaucoma patients. Full article

(This article belongs to the Special Issue Anthocyanins: Recent Progress in Health Benefits Studies)

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