Cyanidin-3-glucoside Research Articles

Rubia sylvatica anthocyanins protect retinal pigment epithelial cells from H2O2-induced oxidative damage

Natural anthocyanins are thought to be protective to eye health due to their recognized antioxidant properties. In this study, the protective effect of Rubia sylvatica fruit anthocyanins against oxidative stress in retinal pigment epithelial (RPE) cells and its mechanism were studied. Overall, Rubia sylvatica anthocyanin extract (RAE), the main anthocyanins found in the RAE, namely Cyanidin-3-O-glucoside (C3G), Delphinidin-3-O-rutinoside (D3R), and Cyanidin-3-O-rutinoside (C3R) all reduced H2O2-induced oxidative stress by decreasing the levels of oxidation products and increasing the activity of antioxidant enzymes. RAE and the three main anthocyanins enhanced cell viability from 54.11% ± 4.03%–85.13% ± 2.37% (RAE), 82.70% ± 2.63% (C3G), 94.00% ± 2.11% (D3R) and 89.99% ± 1.34% (C3R), respectively. And the total apoptosis rate of ARPE-19 cells fell from 14.16% ± 0.86%–9.45% ± 0.22% (RAE), 7.28% ± 0.49% (C3G), 8.88% ± 0.21% (D3R) and 8.59% ± 0.12% (C3R), respectively. The anthocyanins promoted the activation of protein kinase B (Akt) by activating Akt's phosphorylation process to maintain the normal growth and metabolism of cells. These results validate the hypothesis that R. sylvatica anthocyanins may protect against H2O2-induced oxidative injury of RPE through an antioxidant mechanism.

Optimization of fluidized bed agglomeration process for developing a blackberry powder mixture

The research objective was to experimentally optimize the fluidized bed agglomeration process of an agglomerated blackberry powder mixture (ABPM) using the response surface methodology. As a raw material, a powdered mixture of blackberry from Castile (Rubus glaucus Benth) obtained by spray drying (SD) was used. In the evaluation of the agglomeration process, the response surface methodology was applied using a central design with a face-centered composition (α = 1), considering the independent variables: fluidisation air inlet temperature (T) (50–70 °C), the binder solution atomization air pressure (P) (1–2 bar) and process time (t) (20–35 min); and the dependent variable: moisture content (Xw), solubility (S), wettability (We), apparent density (ρa), total phenols (TP), radical scavenging (ABTS·+ and DPPH· methods), anthocyanins (Ant) (cyanidin-3-glucoside (C3G)), ellagic acid (EA) and vitamin C (Vit. C). In general, the ABPM exhibited higher porosity and particle size, which generated changes in S, We and ρa, and a better rehydration capacity of the ABPM. The optimal process conditions (T = 70 °C, P = 1.7 bar and t = 21.7 min) defined the most favourable attributes of the ABPM (Xw = 9.7 ± 0.1%, S = 74.9 ± 4.9%, We = 13.7 ± 3.6 min, ρa = 0.312 ± 0.009 g/mL, TP = 4084.6 ± 30.6 mg AGE/100g dry base (db), ABTS·+ = 4511.4 ± 124.5 mg TE/100 g db, DPPH· = 4182.7 ± 66.4 mg TE/100 g db, Ant = 213.6 ± 15.9 mg C3G/100 g db, EA = 1878.2 ± 45.9 mg/100 g db and Vit. C = 29.8 ± 7.4 mg/100 g db. The agglomeration process improved the instantaneous properties and the flow behaviour of the ABPM. Additionally, it offers significant nutritional value with potential use as an instant drink and raw material for the food industry.

Effects of in vitro fecal fermentation on the metabolism and antioxidant properties of cyanidin-3-O-glucoside

Anthocyanins’ potential health benefits have garnered significant interest. However, due to low bioavailability, the gut microbiota-associated metabolites are suspected to mediate their bioactivity. In this study, cyanidin-3-glucoside (C3G) was fermented with fecal inoculum to simulate colonic microbiota interaction in vitro. The metabolites and antioxidant properties of pre- (P-C3G) and post-fermentation (F-C3G) were determined. Fermentation significantly increased contents of five metabolites (cyanidin, protocatechuic acid, phloroglucinaldehyde, 4-hydroxybenzoic acid and 4-hydroxyphenylacetic acid). Additionally, F-C3G demonstrated superior radicals scavenging than P-C3G, as well as to alleviate H2O2-induced damage in HepG2 cell via increasing superoxide dismutase by 43.26% and catalase by 39.83%, reducing malonaldehyde by 16.40% and cellular ROS production, and activating Nrf2 pathway. Moreover, F-C3G significantly extended the survival rate by 20.67% of Caenorhabditis elegans under heat stress by antioxidation in vivo. This study suggested that anthocyanins metabolism by gut microbiota produce specific metabolites, which potentially exerts protection.

Regulation of mitotic clonal expansion and thermogenic pathway are involved in the antiadipogenic effects of cyanidin-3-O-glucoside.

Introduction: Obesity is a metabolic disease with an increase both in cell size (hypertrophy) and in cell number (hyperplasia) following differentiation of new adipocytes. Adipogenesis is a well-orchestrated program in which mitotic clonal expansion (MCE) occurs in the early step followed by the late terminal differentiation one. Methods: Aim of the study was to evaluate the in vitro effects of cyanidin-3-O-glucoside (C3G), an anthocyanin present in many fruits and vegetables, in the early or late phase of 3T3-L1 preadipocytes differentiation. Results: C3G exposure in the early phase of adipogenesis process induced a more marked reduction of CCAAT/enhancer-binding protein-β (C/EBPβ), peroxisome proliferator-activated receptor γ (PPAR-ɣ) and fatty acid synthase (Fasn) expression than late phase exposure and these effects were associated to a reduced MCE with cell cycle arrest at G0/G1 phase via p21 expression. Furthermore, C3G exposure during the early phase activated AMP-activated protein kinase (AMPK) pathway better than in the late phase promoting the enhancement of beige-like adipocytes. In fact, C3G induced thermogenic biomarkers uncoupling protein-1 (Ucp1) and peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (Pgc1) and these effects were more evident during early phase exposure. Conclusion: Our data demonstrate that C3G reduces the terminal adipogenic process affecting the early phase of differentiation and inducing a thermogenic program.

LncRNA profiles of Cyanidin-3-O-glucoside ameliorated Zearalenone-induced damage in porcine granulosa cells

Long non-coding RNA (lncRNA), a class of RNA molecules with transcripts longer than 200 nt, is crucial for maintaining animal reproductive function. Zearalenone (ZEN) damaged animal reproduction by targeting ovarian granulosa cells (GCs), especially in pigs. Nonetheless, it is not quite clear that whether Cyanidin-3-O-glucoside (C3G) exert effects on porcine GCs (pGCs) after ZEN exposure by altering lncRNA expression. Here, we sought to gain novel information regarding C3G protect against damages induced by ZEN in pGCs. The pGCs were divided into control (Ctrl), ZEN, ZEN + C3G (Z + C), and C3G groups. Results revealed that C3G effectively increased cell viability and suppressed ZEN-induced apoptosis in pGCs. 87 and 82 differentially expressed lncRNAs (DELs) were identified in ZEN vs. Ctrl and Z + C vs. ZEN group, respectively. Gene Ontology (GO) analysis observed that the DELs were related to cell metabolism and cell-matrix adhesion biological processes. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis found that the DELs were associated with the phosphatidylinositide 3-kinases (PI3K)-protein kinase B (AKT) signaling pathway. In brief, we demonstrated that C3G could shield apoptosis induced by ZEN, which may be connected with the changes of lncRNA expression profiles in pGCs. This study complemented our understanding of the genetic basis and molecular mechanisms by which C3G mitigated the toxicity of ZEN in pGCs.

Protection against Metabolic Associated Fatty Liver Disease by Protocatechuic Acid

ABSTRACT Gut microbiota–diet interaction has been identified as a key factor of metabolic associated fatty liver disease (MAFLD). Recent studies suggested that dietary polyphenols may protect against MAFLD by regulating gut microbiota; however, the underlying mechanisms remain elusive. We first investigated the effects of cyanidin 3-glucoside and its phenolic metabolites on high-fat diet induced MAFLD in C57BL/6J mice, and protocatechuic acid (PCA) showed a significant positive effect. Next, regulation of PCA on lipid metabolism and gut microbiota were explored by MAFLD mouse model and fecal microbiota transplantation (FMT) experiment. Dietary PCA reduced intraperitoneal and hepatic fat deposition with lower levels of transaminases (AST & ALT) and inflammatory cytokines (IL-1β, IL-2, IL-6, TNF-α & MCP-1), but higher HDL-c/LDL-c ratio. Characterization of gut microbiota indicated that PCA decreased the Firmicutes/Bacteroidetes ratio mainly by reducing the relative abundance of genus Enterococcus, which was positively correlated with the levels of LDL-c, AST, ALT and most of the up-regulated hepatic lipids by lipidomics analysis. FMT experiments showed that Enterococcus faecalis caused hepatic inflammation, fat deposition and insulin resistance with decreased expression of carnitine palmitoyltransferase-1 alpha (CPT1α), which can be reversed by PCA through inhibiting Enterococcus faecalis. Transcriptomics analysis suggested that Enterococcus faecalis caused a significant decrease in the expression of fibroblast growth factor 1 (Fgf1), and PCA recovered the expression of Fgf1 with insulin-like growth factor binding protein 2 (Igfbp2), insulin receptor substrate 1 (Irs1) and insulin receptor substrate 2 (Irs2). These results demonstrated that high proportion of gut Enterococcus faecalis accelerates MAFLD with decreased expression of CPT1α and Fgf1, which can be prevented by dietary supplementation of PCA.

Characterizing the Gut Microbial Metabolic Profile of Mice with the Administration of Berry-Derived Cyanidin-3-Glucoside.

Dietary modulation of the gut microbiota has recently received considerable attention. It is well established that consumption of berries confers a number of health benefits. We previously reported that a black raspberry (BRB)-rich diet effectively modulates the gut microbiota. Given the role of anthocyanins in the health benefits of berries, coupled with interactions of gut microbial metabolites with host health, the objective of this follow-up study was to further characterize the profile of functional metabolites in the gut microbiome modulated by anthocyanins. We utilized a berry-derived classic anthocyanin, cyanidin-3-glucoside (C3G), combined with a mouse model to probe C3G-associated functional metabolic products of gut bacteria through a mass spectrometry-based metabolomic profiling technique. Results showed that C3G substantially changed the gut microbiota of mice, including its composition and metabolic profile. A distinct metabolic profile in addition to a variety of key microbiota-related metabolites was observed in C3G-treated mice. Microbial metabolites involved in protein digestion and absorption were differently abundant between C3G-treated and control mice, which may be linked to the effects of berry consumption. Results of the present study suggest the involvement of the gut microbiota in the health benefits of C3G, providing evidence connecting the gut microbiota with berry consumption and its beneficial effects.

Study of the scale isolation of anthocyanins from blue corn by flash chromatography

In the current work, a flash chromatography method was developed to separate the main anthocyanins of blue corn; cyanidin-3-glucoside (Cy3G), peonidin-3-glucoside (Pn3G), and cyanidin-3-(6-malonylglucoside) (Cy3MG). These anthocyanins were identified by mass spectroscopy analysis. The implemented method consisted of the isocratic elution in a two-step mixture of methanol: water: acetic acid as the mobile phase (easy to remove) and C18 resin as the stationary phase. In the chromatographic method, different elution conditions were evaluated. The better condition to separate the anthocyanins with glycoside was 5% methanol and 10% acetic acid for 200 minutes of elution, followed by 200 minutes with 25% methanol and 2.5% acetic acid for the malonylglucoside forms. From the chromatograms prepared, the efficiency of the chromatographic separation was evaluated by calculating the parameters: retention factor (), selectivity (), number of theoretical plates (), and resolution (). The optimal values were determined as follows: Cy3G and Cy3MG were as follows: for Cy3G, the rretention factir (k) was dtermined to be 30.2, the selectivity (α) was 1.55, the number of theorical plates (N) was 202, and the resolution (Rs) was 1.09. For Cy3MG, the corresponding values were; k = 104.9, α =1.21, N=522, and Rs 0.093. These parameters are useful to implement separation processes of anthocyanins from other sources of pigmented corn or even others containing anthocyanins.

Strong Allelopathic Activity in Purple Leaves of Transgenic Spiraea cantoniensis Containing Cyanidin 3-Glucoside Assayed by the Protoplast Co-culture Method with Digital Image Analysis

The protoplast co-culture method with digital image analysis (DIA-PP method), was used for in vitro bioassay of allelopathic activity in the leaves of in vitro cultured plants of Spiraea cantoniensis. Purple leaves of transgenic S. cantoniensis, containing an anthocyanin, cyanidin 3-glucoside showed strong inhibitory allelopathic activity, 100% inhibition of recipient lettuce protoplast division by 80 × 103 mL-1 of co-cultured protoplasts, while green leaves of non-transgenic S. cantoniensis showed only 20% inhibition. Cyanidin 3-glucoside which inhibited lettuce protoplast division 80% at 100 µM was evaluated as an allelochemical of transgenic S. cantoniensis. Inhibition was stronger at the cell division stage of lettuce protoplast growth than that at the other stages, i.e., cell wall formation stage and yellow pigment accumulation stage. The results were discussed comparatively with the strong inhibitory activity of non-transgenic S. thunbergii and other allelopathic plant species containing different anthocyanin or carotenoid pigments as putative allelochemicals.

Drying kinetics and quality dynamics of ultrasound-assisted dried selenium-enriched germinated black rice

Black rice is a functional food due to its higher protein, fiber, iron, antioxidant compounds, and other health benefits than traditional rice. The ultrasonic (US) pretreatments (10, 20, and 50 min) followed by hot-air drying (50, 60, and 70 °C) were applied to study the drying kinetics, mathematical modeling, thermodynamics, microstructure, bioactive profile, volatile compounds and to lock the nutritional composition of selenium-enriched germinated black rice (SeGBR). Ultrasonic-treated samples exhibited a 20.5% reduced drying time than control ones. The Hii model accurately describes the drying kinetics of SeGBR with the highest R2 (>0.997 to 1.00) among the fifteen studied models. The activation energy values in US-SeGBR varied from 3.97 to 13.90 kJ/mol, while the specific energy consumption ranged from 6.45 to 12.32 kWh/kg, which was lower than untreated. The obtained thermodynamic attributes of dried black rice revealed that the process was endothermic and non-spontaneous. Gallic acid, kaempferol, and cyanidin 3-glucoside were present in high concentrations in phenolics, flavonoids, and anthocyanins, respectively. The HS-SPME-GC–MS investigation detected and quantified 55 volatile compounds. The US-treated SeGBR had more volatile compounds, which may stimulate the release of more flavorful substances. The scanning electronic micrograph shows that the US-treated samples absorbed high water through several micro-cavities. Selenium concentration was significantly higher in US-treated samples at 50 °C than in control samples. In conclusion, ultrasound-assisted hot-air drying accelerated drying and improved SeGBR quality, which is crucial for the food industry and global promotion of this healthiest rice variety.

A low-power sono-copigmentation of cyanidin 3-glucoside with geranin type-A: An underlying mechanism study with spectroscopic and Surflex docking insights

Liquid-based stuffs rich in natural pigment, especially anthocyanins, are widely distributed globally. The effect of combining between different concentrations of geranin type-A (G) with different time of low-power sonication (GA-LPS) copigments on the colour intensification of cyanidin 3-glucoside (C3G) was studied using multiple spectroscopic and molecular docking approaches. Furthermore, the hyperchromicity of C3G co-pigmented with GA-LPS was evaluated and their colour stability in the liquid models was tested. Results found that the GA-LPS could enhance the C3G-color, especially the G200-60 based blend, mainly due to their high hyperchromicity, pKH-levels, and heat-constancy. The surflex-docking results highlighted that G could strongly bind with C3G, mostly due to their additional –OH, –COOH groups, and delocalization systems. Sono-pigmentation with G interacted with C3G via H-bonding, van der Waals forces, and π–π-sites, mostly owing to these additional groups. Overall, this is the first study on the sono-pigmentation of geranin type-A-anthocyanins to mimic their natural existence and avoid their antagonistic interactions that might be employed as potential food colorings in liquid-based models. It is recommended to further apply GA-LPS on an industrial-based scale with commercial products and under different conditions.

Reinterpretation of anthocyanins biosynthesis in developing black rice seeds through gene expression analysis.

The biosynthesis of anthocyanins is still questionable in regulating the quantities of anthocyanins biosynthesized in rice seeds and the expression levels of transcription factors and the structural genes involved in the biosynthetic pathway of anthocyanins. We herein investigated the relationship between the accumulated anthocyanin contents and the expression levels of genes related to the biosynthesis of anthocyanins in rice seeds. Liquid chromatography/mass spectrometry-mass spectrometry analysis of cyanidin 3-glucoside (C3G) in rice seeds showed no accumulation of C3G in white and red rice cultivars, and the differential accumulation of C3G among black rice cultivars. RNA-seq analysis in rice seeds, including white, red, and black rice cultivars, at twenty days after heading (DAH) further exhibited that the genes involved in the biosynthesis of anthocyanins were differentially upregulated in developing seeds of black rice. We further verified these RNA-seq results through gene expression analysis by a quantitative real-time polymerase chain reaction in developing seeds of white, red, and black rice cultivars at 20 DAH. Of these genes related to the biosynthesis of anthocyanins, bHLHs, MYBs, and WD40, which are regulators, and the structural genes, including chalcone synthase (CHS), flavanone 3-hydroxylase (F3H), flavonoid 3´-hydroxylase (F3´H), dihydroflavonol 4-reductase (DFR), and anthocyanidin synthase (ANS), were differentially upregulated in black rice seeds. The correlation analysis revealed that the quantities of C3G biosynthesized in black rice seeds were positively correlated to the expression levels of bHLHs, MYBs and WD40, CHS, F3H, F3´H, DFR, and ANS. In addition, we present bHLH2 (LOC_Os04g47040) and MYBs (LOC_Os01g49160, LOC_Os01g74410, and LOC_Os03g29614) as new putative transcription factor genes for the biosynthesis of anthocyanins in black rice seeds. It is expected that this study will help to improve the understanding of the molecular levels involved in the biosynthesis of anthocyanins in black rice seeds.

Exploring the Impact of Cyanidin-3-Glucoside on Inflammatory Bowel Diseases: Investigating New Mechanisms for Emerging Interventions.

Cyanidin-3-O-glucoside (C3G), the most widely distributed anthocyanin (ACN) in edible fruits, has been proposed for several bioactivities, including anti-inflammatory, neuro-protective, antimicrobial, anti-viral, anti-thrombotic and epigenetic actions. However, habitual intake of ACNs and C3G may vary widely among populations, regions, and seasons, among individuals with different education and financial status. The main point of C3G absorption occurs in the small and large bowel. Therefore, it has been supposed that the treating properties of C3G might affect inflammatory bowel diseases (IBD), such as ulcerative colitis (UC) and Crohn's disease (CD). IBDs develop through complex inflammatory pathways and sometimes may be resistant to conventional treatment strategies. C3G presents antioxidative, anti-inflammatory, cytoprotective, and antimicrobial effects useful for IBD management. In particular, different studies have demonstrated that C3G inhibits NF-κB pathway activation. In addition, C3G activates the Nrf2 pathway. On the other hand, it modulates the expression of antioxidant enzymes and cytoprotective proteins, such as NAD(P)H, superoxide dismutase, heme-oxygenase (HO-1), thioredoxin, quinone reductase-oxide 1 (NQO1), catalase, glutathione S-transferase and glutathione peroxidase. Interferon I and II pathways are downregulated by C3G inhibiting interferon-mediating inflammatory cascades. Moreover, C3G reduces reactive species and pro-inflammatory cytokines, such as C reactive protein, interferon-γ, tumor necrosis factor-α, interleukin (IL)-5, IL-9, IL-10, IL-12p70, and IL-17A in UC and CD patients. Finally, C3G modulates gut microbiota by inducing an increase in beneficial gut bacteria and increasing microbial abundances, thus mitigating dysbiosis. Thus, C3G presents activities that may have potential therapeutic and protective actions against IBD. Still, in the future, clinical trials should be designed to investigate the bioavailability of C3G in IBD patients and the proper therapeutic doses through different sources, aiming to the standardization of the exact clinical outcome and efficacy of C3G.

Enzymatic acylation of blueberry (Vaccinium ashei) pomace anthocyanins and determination of their cytotoxic properties

To expand the application of acylated blueberry pomace anthocyanins in food and nutraceuticals, their enzymatic acylation reaction and the cytotoxic response were explored. In this study, enzymatic acylation was carried out with cyanidin-3-O-glucoside (C3G) as the main body and Novozyme 435 as the biocatalyst. With a series of improvements, the reaction was carried out under the conditions of lauric acid as the acyl donor, tert-amyl alcohol as the reaction medium, the molar ratio of C3G to lauric acid of 1:10, the reaction time of 24 h and the reaction temperature of 60 °C, and 35.29 % acylation rate was obtained. Moreover, it was found that the lipophilicity, thermostability and photostability of the enzymatic acylated blueberry pomace anthocyanins were improved compared with the untreated blueberry pomace anthocyanins. Cytotoxicity studies showed that acylated blueberry pomace anthocyanins inhibited tumor cells (HeLa, HepG2, and B16 cells) significantly and were less toxic to normal cells (L929 cells) at the maximum concentration (1000 µg/mL) and the longest duration of action (72 h). This study established a method for acylation of blueberry pomace anthocyanins that may be applied to other natural sources of anthocyanins.

Storage stability and multi-spectroscopy analysis of the ternary complex induced by mulberry anthocyanin extract interacting with whey protein isolate and rutin under acidic conditions

In the present study, we have investigated the relevant mechanisms underlying the stabilizing effects of whey protein isolate (WPI) and rutin (Ru) on the mulberry anthocyanin extract (MAE) solution at pH 3.6 during storage. The results demonstrated that there was no pronounced difference in color between the MAE solutions when adding WPI and Ru separately and together. However, the combined use of WPI and Ru reduced the total anthocyanin degradation rate by 16.2% and 18.3% compared to WPI and Ru used individually, respectively, after 9 days of storage at 40 °C. Fluorescence, UV–visible, Fourier transform infrared, and circular dichroism spectroscopies, as well as particle size and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis, indicated that the formation of binary and ternary complexes involving β-lactoglobulin (β-LG), cyanidin-3-O-glucoside (C3G), and Ru. The primary interaction between β-LG and C3G was electrostatic interaction, with an enthalpy change (ΔH) of −25.02 kJ mol−1 and an entropy change (ΔS) of 7.89 J mol−1 K−1 at 298 K, whereas the interactions between β-LG and Ru involved hydrogen bonding and van der Waals force, with ΔH of −124.80 kJ mol−1 and ΔS of −291.72 J mol−1 K−1 at 298 K. Furthermore, a looser, more open, and disordered structure and larger particle size were observed in protein after the addition of C3G/Ru. The presence of Ru in the ternary complex favored the development of these characteristics. Overall, to protect anthocyanins, β-LG and Ru could exert complexation and copigmentation effects on C3G, respectively. The findings of this study provide a foundation for employing ternary complexes to increase the storage stability of anthocyanins.

Metabolome and transcriptome analyses reveal the molecular mechanisms of LcMYB1 regulating anthocyanin accumulation in litchi hairy roots

Agrobacterium rhizogenes-mediated hairy root culture offer a promising approach for gene function analysis and production of plant secondary metabolites. Here, we obtained red litchi hairy roots using A. rhizogenes-mediated LcMYB1 transformation. Using high performance liquid chromatography, the main anthocyanins in the red hairy roots were determined to be cyanidin 3-rutinoside and cyanidin 3-glucoside. A total of 164 metabolites were significantly upregulated or downregulated in the red hairy roots, which were mostly involved in flavone and flavonol pathway, and flavonoid pathway. The transcriptome analysis revealed 472 differentially expressed genes (DEGs). Up-regulated genes were considerably enriched in anthocyanin, flavone and flavonol biosynthesis. Integrative metabolite profiling and transcriptome analyses showed that LcF3′H, LcUFGT1, and LcGST4 were key structural genes in anthocyanin biosynthesis. However, the expression of Cinnamyl-alcohol dehydrogenase (CAD) and Peroxidase (POD) leading to the production of lignin were significantly down-regulated, suggesting flavonoids and lignin compete with each other in the phenylpropanoid pathway. A total of 52 DEGs were identified as transcription factors. Correlation analysis showed that 8 transcription factors were positively correlated with LcUFGT1, and LcGST4, involving in anthocyanin biosynthesis. These findings clarify the molecular mechanisms of LcMYB1 regulating anthocyanin accumulation in litchi hairy roots.

Anthocyanin and proanthocyanidin from Aronia melanocarpa (Michx.) Ell.: Purification, fractionation, and enzyme inhibition.

Aronia melanocarpa (Michx.) Ell. is a rich source of anthocyanins and proanthocyanidins with confirmed health benefits. Individual cyanidin glucosides (cyanidin 3-galactoside, cyanidin 3-arabinoside, cyanidin 3-xyloside, and cyanidin 3-glucoside) of anthocyanins (calculated by individual cyanin glycoside fractions was 419.9 mg/100 g FW) were isolated by Sephadex LH-20 column and different parts of proanthocyanidins with a different mean degree of polymerization (mDP) were fractionated by the solubility differences in different solvents. The composition of different mDP of proanthocyanidins was as follows: monomers (1.51%), oligomer (mDP of 4.2 ± 0.9, 20.57%), CPP-50 (mDP of 78.9 ± 4.1, 22.17%), CPP-60 (mDP of 66.1 ± 1.2, 27.94%), CPP-70 (mDP of 36.8 ± 3.9, 36.8%), CPP-75 (mDP of 25.2 ± 1.3, 6.14%), CPP-L (mDP of 10.2 ± 2.6, 6.95%), and there were recycling loss of 0.34%. Cyanidin 3-glucoside showed the strongest inhibition effects on α-amylase and lipase and cyanidin 3-arabinoside showed the strongest inhibition effect on α-glucosidase, while cyanidin 3-xyloside has no inhibition effect on the α-amylase, and cyanidin 3-galactoside, cyanidin 3-arabinoside, and cyanidin 3-xyloside have no inhibition effects on lipase. The inhibition effect of proanthocyanidins with different mDP to the enzymes all showed high negative correlations between the mDP and IC50 (half-maximal inhibitory concentration). This study suggests that A. melanocarpa (Michx.) Ell. can have beneficial effects due to inhibition of the digestion enzyme.

Pressurized liquid extraction as an eco-friendly approach to recover anthocyanin from black rice bran

This study aimed to recover the anthocyanin-rich extract from black rice bran by pressurized liquid extraction (PLE) and compare with the conventional process (heating-stirring extraction - HSE). PLE performs fast and efficiently and results in high yields in less time and less solvent, being considered eco-friendly. The extracts were characterized for thermal and light stabilities, cytotoxicity, antitumoral activity, and cytoprotective effect. Optimum PLE conditions were: 55 °C, a flow rate of 5 mL/min, and solution ethanol:citric acid 0.1 mol/L (50:50, v/v). PLE recovered about 80% of total anthocyanins (2.33 mg/C3GE g), while HSE recovered 46% (1.17 mg/C3GE g). Cyanidin-3-O-glucoside (C3G) was identified (m/z 449) and quantified, 1.63 mg/g for PLE and 1.07 mg/g for HSE. Both anthocyanin-rich extracts in low temperature showed high thermostability, did not present cytotoxicity (normal fibroblast L929 cells), and showed cytoprotection of L929 cells when subjected to oxidative stress with H2O2. Overall, the anthocyanin-rich extracts obtained by PLE showed potential to be applied as natural colorants and possibly to improve wound healing. Industrial relevancePLE method is an eco-friendly technology that performs fast and efficient extractions under high temperature and pressure conditions. This study provides information about the extraction of anthocyanin-rich extracts from black rice bran by green PLE process under optimized conditions. The process allowed for obtaining antioxidant-rich extracts with no cytotoxicity and a high potential for application in the food, cosmetic, and biomedical industries.

Standardization of açaí extracts for in-vitro assays based on anthocyanin quantitation.

Euterpe oleracea Mart., commonly known as açaí, is a fruit that grows on a palm tree native to the Amazon region. Quantitation of bioactive constituents is a crucial preliminary step before utilizing extracts for biological assays so they may be normalized and administered according to a specific constituent concentration. Açaí has four main anthocyanin analytes: cyanidin 3-glucoside, cyanidin 3-sambubioside, cyanidin 3-rutinoside, and peonidin 3-rutinoside. This is the first comparison of açaí anthocyanin profiles between fresh fruits, processed powders, and botanical dietary supplement capsules. The materials examined shared a similar anthocyanin profile, with cyanidin 3-rutinoside being the most abundant (0.380 ± 0.006 - 15.1 ± 0.01 mg/g), followed by cyanidin 3-glucoside (0.0988 ± 0.0031 - 8.95 ± 0.01 mg/g). Among the botanical dietary supplement capsules, the two formulations varied greatly in anthocyanin concentration despite both being aqueous extracts (0.650 ± 0.011 - 0.924 ± 0.010 mg/g versus 1.23 ± 0.01 - 1.27 ± 0.02 mg/g). Previous LC-MS methods range from 35-120 min per injection, while we report a 10 min quantitative method for analysis of anthocyanins in various açaí materials that is fast, reproducible, and accurate. The method produced is useful to assure the quality, efficacy and safety of food and dietary supplement materials containing açaí.

A study of cyanidin/alginate complexation: Influence of pH in assembly and chiral properties

Cyanidin 3-O-glucoside (CND) is a frequently-used anthocyanin that has excellent antioxidant properties but a limited bioavailability in bloodstream. Complexation of CND with alginate can improve its therapeutic outcome. Here we have studied the complexation of CND with alginate under a range of pH values from 2.5 to 5. CND is positively charged at low pH, and becomes neutral, and then negatively charged as pH increases. CND/alginate complexation was studied by dynamic light scattering, transmission electron microscopy, small angle X-ray scattering, STEM, UV–Vis spectroscopy and circular dichroism (CD). CND/alginate complexes at pH 4.0 and 5.0 form chiral fibres with a fractal structure. At these pH values, CD spectra show very intense bands, which are inverted compared with free CND. Complexation at lower pH results in disordered polymer structures and CD spectra show the same features as for CND in solution. Molecular dynamics simulations suggest the formation of parallel CND dimers through complexation with alginate at pH 3.0, while at pH 4.0 CND dimers form in a cross like arrangement.