Black Rice Anthocyanins Research Articles

Protective effect and mechanism of action of xanthan gum on the color stability of black rice anthocyanins in model beverage systems

We investigated the effect and mechanism of action of xanthan gum (XG) on the color stability of black rice anthocyanins (BRA) in model beverage systems (pH 3.0) containing l-ascorbic acid under different conditions. The color stability of BRA was significantly enhanced in the presence of XG under accelerated storage conditions (40 °C), particularly at 0.25% (w/v). The degradation of BRA followed a first-order reaction rate (R2 > 0.89) during storage and thermal processing conditions. The addition of XG effectively improved the storage stability of BRA in the presence of l-ascorbic acid, particularly at 4 °C in the dark. Moreover, the thermal stability of BRA was enhanced by XG under thermal treatment (80 °C, 90 °C and 100 °C). The FTIR spectrum, X-ray diffraction and molecular simulation results showed that the interaction between XG and BRA was driven mainly by hydrogen bonds and hydrophobic interactions, leading to the increased stability of BRA. Our study demonstrated the benefits of using XG to improve the color stability of BRA in model beverage systems, further expanding the practical application of XG in anthocyanin-rich beverages.

Inhibition of Lipid and Protein Oxidation in Whey-Protein-Stabilized Emulsions Using a Natural Antioxidant: Black Rice Anthocyanins.

The food industry is exploring the natural environment to identify botanical extracts that can be used as functional ingredients that can replace synthetic ingredients in foods. In the present study, the ability of black rice anthocyanins as natural antioxidants to inhibit both lipid and protein oxidation in protein-stabilized oil-in-water emulsions was examined. Whey-protein-stabilized emulsions were prepared containing 0, 0.02, 0.04, and 0.06% (w/v) anthocyanins, and then the impact of this plant-based extract on their physical and chemical stabilities was evaluated. The addition of the anthocyanins improved the physical stability of the emulsions in a dose-dependent manner by inhibiting droplet aggregation during storage (35 °C for 5 days). The anthocyanins also exhibited good antioxidant activity in a dose-dependent manner, as seen by their capacity for inhibiting both lipid oxidation (reduced lipid hydroperoxides and malondialdehyde) and protein oxidation (reduced carbonyl and Schiff base formation, intrinsic fluorescence loss, and molecular weight changes). Black rice anthocyanins may therefore be an effective botanical extract for improving the stability of protein-stabilized food emulsions by inhibiting oxidative reactions.

PH-dependent antioxidant stability of black rice anthocyanin complexed with cycloamylose

This study investigated the effects of cycloamylose (CA) as a complexing agent on the antioxidant activity and stability of anthocyanin extracted from black rice (BRA) at various pHs (2, 4, 6, and 8) and compared the results with those of β-cyclodextrin (βCD). The CA (DP 6–31) produced from Dodamssal rice starch had an anti-copigmentation effect for BRA and the discoloration effect increased with the complexing agent concentration, which supported the intramolecular interaction between them. With heat treatment, the CA-BRA complex had a greater antioxidant stability than did free BRA at pHs 4, 6, and 8 in a concentration-dependent manner. In particular, BRA complexed with 1% CA at pH 4 had an approximately 2.0-fold lower degradation rate (kd) than that of free BRA. This improvement in the thermal stability was comparable to or slightly better than that of 5% βCD. CA significantly improved the photostability of BRA at all pHs tested, similarly to βCD. CA might protect the moiety of BRA functional groups that are involved in antioxidant activity and susceptible to heat and light. The results demonstrated that CA could be an effective complexing agent for BRA and the stable CA-BRA complex could be used as a promising functional material for the various industries.

Antioxidant extraction based on black rice (Oryza Sativa L. Indica) to prevent free radical

Free radicals are molecules that in their outer orbit have one or more unpaired electrons; they are very labile and very reactive. These molecules have an important role in tissue damage and pathological processes in living organisms. Antioxidants are compounds that can inhibit oxidation reactions by binding free radicals. The antioxidants produced by the human body are very limited, so we need the intake of antioxidants from outside, especially those from food. Research on antioxidant extraction based on black rice (Oryza Sativa L.Indica) to prevent free radicals has been carried out. This research was conducted using the DPPH method to measure the ability to capture free radicals and FRAP methods to measure antioxidant capacity. This study aimed to obtain data on the level of antioxidant activity contained in black rice and its effect to counteract free radicals. The result showed that the ability to capture free radicals contained 25ppm DPPH anthocyanin extract could inhibit 55,00%. While using the FRAP method, the results of black rice anthocyanin extract have a high antioxidant capacity of 824 ± 17.24 μM. It is evident that the DPPH method used to show in anti-oxidant extracts based on black rice can capture free radicals, while the FRAP method proves that antioxidants in black rice have the capacity to prevent free radicals in the body.

Dietary Supplementation of Black Rice Anthocyanin Extract Regulates Cholesterol Metabolism and Improves Gut Microbiota Dysbiosis in C57BL/6J Mice Fed a High-Fat and Cholesterol Diet.

This study explores the beneficial effects of dietary supplementation of black rice anthocyanin extract (BRAE) on cholesterol metabolism and gut dysbiosis. C57BL/6J mice are grouped into the normal chow diet group (NCD), the high-fat and the cholesterol diet group (HCD), and three treatment groups feeding HCD supplemented with various dosage of BRAE for 12 weeks. Results reveal that BRAE alleviates the increased body weight, serum triglyceride (TG), total cholesterol (TC), non-high-density lipoprotein cholesterol levels (non-HDL-C), and increased fecal sterols excretion and caecal short-chain fatty acids (SCFAs) concentration in HCD-induced hypercholesterolemic mice. Moreover, BRAE decreases hepatic TC content through the fundamental regulation of body energy balance gene, adenosine 5'-monophosphate activated protein kinase α (AMPKα). Meanwhile, BRAE improves the genes expression involved in cholesterol uptake and efflux, and preserves CYP7A1, ATP-binding cassette subfamily G member 5/8 mRNA expression, and the relative abundance of gut microbiota. Additionally, the antibiotic treatment experiment indicates that the beneficial effects of BRAE in reducing hypocholesterolemia risk largely depends on the gut microbiota homeostasis. BRAE supplement could be a beneficial treatment option for preventing HCD-induced hypocholesterolemia and related metabolic syndromes.

Stabilization of black rice anthocyanins by self-assembled silk fibroin nanofibrils: Morphology, spectroscopy and thermal protection

Nanofibrillated proteins possess diverse techno-functional properties are considered as matrices for stabilizing bioactive agents. In this study, the morphology and interaction of silk fibroin nanofibrils (SNFs) with black rice anthocyanins (ACN) were investigated through multiple microscopy and spectroscopic techniques. The impact of SNFs on the thermal stability of ACN was analyzed. Nanofibrils with diameter less than 20 nm were self-assembled from silk fibroin (SF) lyophilized powder solution at pH 6.0. A static model occurred in the interactions of cyanidin-3-O-glucoside (C3G, the major anthocyanin in black rice) with SF and SNFs. C3G binding altered the secondary structures of SF and SNFs. Moreover, the thermal retention rates of ACN combined with SF and SNFs were significantly (P < 0.05) higher than that of ACN alone followed the order of SNFs-ACN (60.87%) > SF-ACN (57.47%) > ACN alone (40.33%) after heating 120 min at 80 °C and SNFs-ACN (50.42%) > SF-ACN (32.81%) > ACN alone (23.64%) after heating 120 min at 90 °C. The half-life (t1/2) of thermal degradation of ACN was elongated in SNFs-ACN complex compared with that in SF-ACN complex. These results showed that SNFs effectively binding with C3G and exhibit better protective effects on the thermal stability of ACN than SF.

Phenolic Content and Antioxidant Activity of Black Glutinous Rice Anthocyanin during Fermentation by Pediococcus pentosaceus N11.16

Anthocyanin was developed into natural food colorant in microemulsion systems to improve their stability and readiness for food preparation. Anthocyanin has an antioxidant activity. The degradation of anthocyanin into small compound could increase the biological activity. Anthocyanin was extracted from black glutinous rice and prepared using food grade surfactant such as Tween 80, Tween 20, and Span 80. Microemulsion was then added into modified deMann Rogosa Sharp (MRS) medium as much as 5, 10, 15, 20 and 25 ppm. Lactic acid bacteria genus Pediococcus pentosaceus N11.16 were grown for 18–24 hours and were used as enzyme producers. This experiment was aimed to determine the stability of anthocyanin in microemulsion systems to enzymatic degradation. The modified MRS medium was added with microemulsion and incubated for 24 h. Phenolic content remained stable during the fermentation process in all treatments, while the highest antioxidant activity was found in the sample with 20 ppm of anthocyanin. Total acid-producing bacteria were also monitored during the incubation and the result showed that there was a decline in their growth. There was a significant change in the antioxidant activity during incubation.

Black Rice Anthocyanin in Mixed Meals: Influence on Postprandial Glycaemic and Lipid Responses Among Healthy Individuals

Black Rice Anthocyanin in Mixed Meals: Influence on Postprandial Glycaemic and Lipid Responses Among Healthy Individuals

Natural Plants Compounds as Modulators of Epithelial-to-Mesenchymal Transition.

Epithelial-to-mesenchymal transition (EMT) is a self-regulated physiological process required for tissue repair that, in non-controled conditions may lead to fibrosis, angiogenesis, loss of normal organ function or cancer. Although several molecular pathways involved in EMT regulation have been described, this process does not have any specific treatment. This article introduces a systematic review of effective natural plant compounds and their extract that modulates the pathological EMT or its deleterious effects, through acting on different cellular signal transduction pathways both in vivo and in vitro. Thereby, cryptotanshinone, resveratrol, oxymatrine, ligustrazine, osthole, codonolactone, betanin, tannic acid, gentiopicroside, curcumin, genistein, paeoniflorin, gambogic acid and Cinnamomum cassia extracts inhibit EMT acting on transforming growth factor-β (TGF-β)/Smads signaling pathways. Gedunin, carnosol, celastrol, black rice anthocyanins, Duchesnea indica, cordycepin and Celastrus orbiculatus extract downregulate vimectin, fibronectin and N-cadherin. Sulforaphane, luteolin, celastrol, curcumin, arctigenin inhibit β-catenin signaling pathways. Salvianolic acid-A and plumbagin block oxidative stress, while honokiol, gallic acid, piperlongumine, brusatol and paeoniflorin inhibit EMT transcription factors such as SNAIL, TWIST and ZEB. Plectranthoic acid, resveratrol, genistein, baicalin, polyphyllin I, cairicoside E, luteolin, berberine, nimbolide, curcumin, withaferin-A, jatrophone, ginsenoside-Rb1, honokiol, parthenolide, phoyunnanin-E, epicatechin-3-gallate, gigantol, eupatolide, baicalin and baicalein and nitidine chloride inhibit EMT acting on other signaling pathways (SIRT1, p38 MAPK, NFAT1, SMAD, IL-6, STAT3, AQP5, notch 1, PI3K/Akt, Wnt/β-catenin, NF-κB, FAK/AKT, Hh). Despite the huge amount of preclinical data regarding EMT modulation by the natural compounds of plant, clinical translation is poor. Additionally, this review highlights some relevant examples of clinical trials using natural plant compounds to modulate EMT and its deleterious effects. Overall, this opens up new therapeutic alternatives in cancer, inflammatory and fibrosing diseases through the control of EMT process.

Effect of wall materials on some physicochemical properties and release characteristics of encapsulated black rice anthocyanin microcapsules

Anthocyanin-rich extracts derived from the bran of a select Thai black rice cultivar, Leum Pua, were encapsulated by spray drying. In this microencapsulation method, twelve wall materials comprising maltodextrin (M), gum arabic (G), whey protein isolate (W), and their combinations were employed. For comparison, an ionic gelation method was employed using alginate-whey protein isolate (AL-W) as a wall material. Thirteen microcapsules were analysed by scanning electron microscopy, and their encapsulation efficiencies were almost 100%, except for that of the W (83%). M (88%) and its combination with W exhibited the best anthocyanin retention, while pure W contained the highest amount of total phenolic compounds and antioxidant activity. An in vitro digestion study using simulated gastrointestinal fluids revealed the highest released total phenolic content and antioxidant activity of the intestinal fluids when the microcapsule was spray-dried with pure W.

Transcriptomic analysis of the life-extending effect exerted by black rice anthocyanin extract in D. melanogaster through regulation of aging pathways.

This study examined the beneficial effects of black rice anthocyanin extract (BRAE), which provides as an excellent source of dietary antioxidants, on the lifespan of fruit flies and the underlying molecular mechanisms. Results showed that supplementation of BRAE extended the lifespan of fruit flies by 20% and retarded the loss of locomotor function. Comparison of mRNA transcriptome profile between fruit flies of 20 days and 50 days after the start of normal diet and normal diet supplemented with BRAE (5 mg/mL) identified 6687 differentially expressed coding genes. A large number of these differentially expressed mRNAs were enriched in KEGG (Kyoto Encyclopedia of genes and genomes) analysis. KEGG pathway analysis demonstrated that up regulation in the glutathione metabolism, neuroactive ligand-receptor interaction, and down regulation in FoxO signaling pathway, mTOR signaling pathway were most likely affected by supplementation of BRAE. In addition, several genes, including Zw (Zwischenferment), GstD2, GstE1, Gpx, Gclm, Tsc1, 4E-BP, DopR and D2R, which were involved in the pathways mentioned above, could be regulated by the supplementation of BRAE. Together, the results implicated that the expression of most of the mRNAs in fruit fly were closely associated with BRAE diet, which could provide a resource of mRNAs related in the field of aging and aging-related disease.

Virtual Prediction of the Delphinidin-3-O-glucoside and Peonidin-3-O-glucoside as Anti-inflammatory of TNF-α Signaling.

Introduction:Anthocyanin is the bioactive compound in black rice, which promotes some health benefits for human body. Present study revealed that black rice anthocyanins improve the biomarker of the metabolic syndrome, such as tumor necrosis factor alpha (TNF-α). However, the mechanism of anthocyanin in preventing metabolic syndrome has not been elucidated.Aim:This study was performed to identify the interaction of six types of black rice anthocyanin towards TNF-α protein and TNF-α receptor through in silico studies, to assess the molecular properties and bioactivity of black rice anthocyanin.Methods:We retrieved the black rice anthocyanin compounds from the PubChem database and the proteins (TNF-α protein and TNF-α receptor) from Protein Data Bank (PDB) database. Protein and ligands were docked using Hex 8.0 software and visualized by Discovery Studio 4.1 program.Results:This study found the possibility that black rice anthocyanins interacted with TNF-α have no influence into TNF-α and TNF-α receptor interaction. The binding of delphinidin-3-O-glucoside & peonidin-3-O-glucoside to TNF-α receptor inhibited the TNF-α and TNF-α receptor signaling. The black rice anthocyanins had low activity as a drug. Interestingly, black rice anthocyanins had a potency as an antioxidant due to the hydrogen donor or acceptor in their structure, as protein kinase inhibitor, nuclear receptor ligand, and enzyme kinase inhibitor.Conclusion:This study suggests that delphinidin-3-O-glucoside and peonidin-3-O-glucoside might have function as anti-inflammatory factor related with TNF-α signaling.

黑米花青素酶法提取工艺优化及颜色稳定性测定

黑米花青素酶法提取工艺优化及颜色稳定性测定

Anthocyanin-rich extract from black rice (Oryza sativa L. Japonica) ameliorates diabetic osteoporosis in rats.

Diabetic osteoporosis (DOP) is a systemic endocrine-metabolic osteopathy which has the characteristics of bone mineral density (BMD) reduction and bone microstructural destruction. Although anthocyanin-rich extract from black rice (AEBR) was reported to have a beneficial effect on diabetic rats, no studies have been performed on whether black rice anthocyanins are beneficial for diabetic osteoporosis. Therefore, in this study, a streptozotocin-induced diabetic rat model was established to investigate the protective effect of AEBR on diabetes-induced osteoporosis and its possible mechanism. AEBR at three doses (0.5, 1.0, and 2.0 g kg-1 d-1) were administered by oral gavage to diabetic rats for 8 weeks. The blood glucose, BMD, bone histomorphometry parameters, serum bone turnover biomarkers, bone marrow adipocyte numbers, as well as osteoprotegerin (OPG), runt-related transcription factor 2 (RUNX 2), and receptor activator of nuclear factor-κ B ligand (RANKL) protein expression in bone and serum were detected. The results indicated that AEBR dose-dependently decreased the blood glucose, increased the BMD, and decreased the serum bone turnover markers. The bone microstructure and osteoclast numbers in bone tissues returned to normal in the high AEBR dosage group; at the same time, the AEBR dose-dependently suppressed bone marrow adipogenesis. The RUNX 2 as well as the OPG/RANKL ratio in diabetic rats' bone tissues increased significantly in the AEBR treatment group. Our results indicate that AEBR administration can ameliorate bone loss caused by diabetes; this is mainly attributed to its inhibition of bone turnover, suppression of bone marrow adipogenesis, and up-regulation of RUNX 2 and the OPG/RANKL expression ratio.

Covalent conjugates of anthocyanins to soy protein: Unravelling their structure features and in vitro gastrointestinal digestion fate

Seeking for healthier dietary foods without compromising their quality has become the first choice for consumers. Various components in foods are able to interact with each other and form conjugates to improve their functionality and nutritional value. The present study investigated on the formation and structural properties of covalently linked conjugates using soy protein isolate (SPI) and black rice anthocyanins at different ratios. The in vitro digestion fate of the conjugates under simulated gastrointestinal conditions was also evaluated. Fourier transform infrared spectroscopy analysis indicated that the secondary structures of SPI was changed upon conjugation with anthocyanins as there was a decrease in α-helix and β-sheet content. Three-dimensional fluorescence also revealed that the tertiary structure of SPI was less compact after conjugation with anthocyanins as a result of the unfolding of polypeptide chains. The conjugates were shown to have higher degree of hydrolysis than SPI. However, transepithelial transport of peptides across Caco-2 cell monolayer was decreased in SPI after conjugation with anthocyanins. The results of this study suggest that incorporation of anthocyanins in SPI is a way to reconcile consumer demand for healthier foods with better quality and functionality.

Metabolism and prebiotics activity of anthocyanins from black rice (Oryza sativa L.) in vitro.

Anthocyanins are naturally active substances. In this study, anthocyanins from black rice were obtained by membrane filtration and column chromatography separation. Five anthocyanin monomers in black rice extract were identified by HPLC-MS/MS, and the major anthocyanin monomer (cyanidin-3-glucoside, C3G) was purified by preparative HPLC (Pre-HPLC). The proliferative effects of the anthocyanins on Bifidobacteria and Lactobacillus were investigated by determining the media pH, bacterial populations and metabolic products. After anaerobic incubation at 37 °C for 48 h, not only the pH of the media containing C3G was lower than that of the extract of black rice anthocyanin (BRAE), but the numbers of both Bifidobacteria and Lactobacillus were also significantly increased. Furthermore, hydroxyphenylpropionic, hydroxyphenylacetic, and hydroxybenzoic acids and other metabolites were detected by GC-MS in vitro. Our results revealed that the anthocyanins and anthocyanin monomers from black rice had prebiotic activity and they were metabolized into several small molecules by Bifidobacteria and Lactobacillus.

English

In a previous study, it was reported that Enterobacter aerogenes and four organic acids are involved in the alteration of black rice anthocyanins. To investigate the factors involved in altering the coloration of black rice anthocyanins, organic acids (caffeic acid, ferulic acid, malonic acid, and p-hydroxybenzoic acid) were individually added to potato dextrose agar medium containing black rice anthocyanins and cultured with E. aerogenes NBRC 13534 at 37&deg;C for five days. As a result, the color change of black rice anthocyanins was found in the medium supplemented with caffeic acid or ferulic acid among the four organic acids. HPLC analysis of anthocyanins in each medium revealed three new peaks not found in the original black rice anthocyanins in the sample supplemented with caffeic acid. Also, two new peaks were observed in the medium supplemented with ferulic acid. &nbsp; Key words: Anthocyanin, anthocyanin modification, black rice, Enterobacter aerogenes, microorganism, color, pigment.

Black rice-derived anthocyanins inhibit HER-2-positive breast cancer epithelial-mesenchymal transition-mediated metastasis invitro by suppressing FAK signaling.

This study aimed to investigate the role of focal adhesion kinase (FAK) signaling in the inhibitory effects of black rice anthocyanins (BRACs) on human epidermal growth factor receptor-2 (HER-2)-positive human breast cancer cell metastasis, using the MCF-10A, MCF-7 and MDA-MB-453 cells. BRACs exerted an anti-metastatic effect on the HER-2-positive breast cancer cells. The effects of BRACs on the proliferation of the MDA-MB-453 cells were examined by cell counting kit-8 assay. A wound-healing assay was used to examine the effects of BRACs on the migration of the breast cancer cells. BRACs interrupted migration and invasion. BRACs decreased the migration distance of the HER-2-positive human breast cancer cells, MDA-MB-453, by 37% compared with the cells in the untreated group. They also reduced the number of invading MDA-MB-453 cells by 68%. In addition, BRACs exerted an inhibitory effect on epithelial-mesenchymal transition. Western blot analysis revealed that BRACs decreased the phosphorylation of FAK, cSrc and p130Cas. The FAK inhibitor, Y15, was also used to further evaluate the role of FAK signaling in the anti-metastatic effects of BRACs on MDA-MB-453 cells. The results of western blot analysis revealed that BRACs increased the expression of the epithelial marker, E-cadherin, and decreased the expression of the mesenchymal markers, fibronectin and vimentin, in the MDA-MB-453 cells. In addition, BRACs decreased the interaction between HER-2 and FAK, FAK and cSrc, cSrc and p130Cas, and between FAK and p130Cas. These results suggest that BRACs suppress the metastasis of HER-2-positive breast cancer in vitro, and that the cSrc/FAK/p130Cas pathway plays a vital role in this inhibitory effect.

Anthocyanins in black rice, soybean and purple corn increase fecal butyric acid and prevent liver inflammation in high fat diet-induced obese mice.

Epidemiological evidence indicates that anthocyanin consumption reduces the incidence of chronic and degenerative diseases. Therefore, the present study aimed to determine whether black rice anthocyanin (BRA), black soybean anthocyanin (BSA), and purple corn anthocyanin (PCA) could mitigate oxidative stress and inflammation associated obesity in C57BL/6 mice fed with a high-fat diet. BRA, BSA, or PCA was administered at doses of 200 mg kg-1 throughout the 12-week experiment and reduced the bodyweight by 9.6%, 13.3%, or 16.6%, respectively. Furthermore, BRA, BSA or PCA administration could effectively increase fecal butyric acid levels, elevate hepatic SOD and GPx activities, decrease lipid peroxidation, and downregulate the gene expression levels of TNFα, IL-6, iNOS, and NF-κB. Hence, BRA, BSA, or PCA might ameliorate diet-induced obesity by alleviating both oxidative stress and inflammation.

Black Rice Anthocyanin Content Increases with Increase in Altitude of its Plantation

Black Rice Anthocyanin Content Increases with Increase in Altitude of its Plantation