Natural Food Dyes Research Articles

PASTRIES WITH FUNCTIONAL SPIRULINA PLATENSIS INGREDIENTS

The aim of the research is to develop new bakery products with increased functional value by adding ingredients from the biomass of Spirulina platensis. High quality wheat flour (P1), oatmeal (P2) and whole wheat flour (P3) sticks were formulated with the addition of 3% S2 preparation based on spirulina, thus increasing the bioavailability of the active components in microalgae. It was established that the addition of S2 preparation in sticks results in an increase in the total polyphenol content by 41.67% in the P2 samples of oatmeal sticks and by 56.17% in the P3 samples of whole wheat flour. The addition of S2 leads to a decrease in the content of reducing sugars by up to 2.56% in P1, by 2.50% in P2 and by 2.19% in P3 compared to the control. In sticks with the addition of S2, the fat content of cyanobacterial origin increases by almost 3.2% in sample P1, by 4.4% in P2 and by 6.0% in P3 compared to the control samples. The research results show that the use of the preparation based on Spirulina platensis contributes to increasing the nutritional value of flour products through the increased intake of amino acids, fatty acids of cyanobacterial origin, minerals, vitamins and bioactive substances, which are missing in conventional products, consumed daily. The S2 preparation based on microalgae, rich in pigments - chlorophylls, carotenes and phycocyanins with beneficial properties for health, could be used as a natural food dyes.

Solar Dryer with Reheating System for Annatto Fruit Pericarp

Annatto fruit is one of the sources of natural food dye coming from its seeds. Aside from this part, the pericarp of the annatto fruit is a candidate for potential source of fuel. It is necessary for the pericarp to undergo drying prior to biomass energy conversion. The pericarp can be dried at least five days in sun drying to remove the seeds. In line with this, the researchers had designed a solar cabinet dryer introducing a reheating system and gravel used as thermal storage to lessen the drying time of the annatto fruit pericarp. The solar cabinet dryer had a multi layered wire mesh inside the drying cabinet that allows hot air from the collector to circulate and evenly dry the pericarp. Using the solar cabinet dryer, the drying time was lessened to seven hours with a drying rate of 4.37 g/min. The experiment compared three modes of drying consists of no reheating, with partial reheating and full reheating. During the drying process, several parameters such as the temperature, humidity and mass of each tray were measured, recorded and analyzed. It is found out that fully opened reheater has the highest moisture removed with 90.38% system efficiency.

The Inactivation by Curcumin-Mediated Photosensitization of Botrytis cinerea Spores Isolated from Strawberry Fruits.

Photosensitization is a novel environmentally friendly technology with promising applications in the food industry to extend food shelf life. In this study, the natural food dye curcumin, when combined with visible light (430 nm), was shown to be an effective photosensitizer against the common phytopathogenic fungi Botrytis cinerea (the cause of grey mould). Production of the associated phytotoxic metabolites botrydial and dihydrobotrydial was measured by our newly developed and validated HRAM UPLC-MS/MS method, and was also shown to be reduced by this treatment. With a light dose of 120 J/cm2, the reduction in spore viability was directly proportional to curcumin concentrations, and the overall concentration of both botrydial and dihydrobotrydial also decreased with increasing curcumin concentration above 200 µM. With curcumin concentrations above 600 µM, the percentage reduction in fungal spores was close to 100%. When the dye concentration was increased to 800 µM, the spores were completely inactive and neither botrydial nor dihydrobotrydial could be detected. These results suggest that curcumin-mediated photosensitization is a potentially effective method to control B. cinerea spoilage, and also to reduce the formation of these phytotoxic botryane secondary metabolites.

Ameliorative effect of betanin on experimental cisplatin-induced liver injury; thenovel impact of miRNA-34a on the SIRT1/PGC-1α signaling pathway.

The anticancer agent, cisplatin (CIS), is associated with hepatotoxic effects related to activation of oxidative stress and inflammation pathways. CIS-induced oxidative DNA damage reduces sirtuin 1 (SIRT1) activity, which in turn, modulates the activity of peroxisome proliferator-activated receptor-gamma coactivator 1-alpha (PGC-1α). Moreover, microRNA-34a (miRNA-34a) was shown to hinder both SIRT1 and nuclear factor erythroid 2-related factor 2 (Nrf2) activity. Thus, targeting such a pathway can alleviate CIS-induced hepatotoxicity. Betanin (BET) is a natural red glycoside food dye obtained from beets, which is reported to exhibit antioxidant function. However, its role in CIS-induced liver injury and the molecular mechanism has not been fully elucidated. Thus, the aim of this study was to investigate the ameliorative effect of BET on CIS-induced acute hepatotoxicity through the SIRT1/PGC-1α signaling pathway and illustratethe impact of miRNA-34a. Seventy-two rats were divided into six equal groups: (1) Control, (2) BET, (3) CIS, (4) CIS/BET, (5) CIS/EX527, and (6) CIS/BET/EX527. CIS-induced liver injury was evidenced by deregulated BAX and BCL2 levels, decreased levels of AMP-activated protein kinase and PGC-1α expression, and decreased SIRT1 activity. Consequently, reduced levels of Nrf2 and the expression of associated heme oxygenase-1 and glutamate-cysteine ligase modifier subunit were observed. Intriguingly, BET succeeded inreducingthe CIS-induced liver injury through reducing miRNA-34a expression and enhancing the SIRT1/PGC-1α pathway. These findings coincide with the molecular docking results and the histopathological picture. In conclusion, the current research provided novel findings of the BET ameliorative effect on CIS-induced liver injury through modulating miRNA-34a expression and the SIRT1/PGC-1α signaling cascade.

Mirabilis jalapa Flower Extract as Therapeutic Agent and Cellular Delivery by Nanoparticles

Bio friendly green modest syntheses of nanoparticles are the present research in the extremity of nanotechnology. This study has been undertaken to explore the determinants of iron nanoparticles from 1 mM FeSO4 solution through profuse concentration of aqueous flower extract of Mirabilis jalapa reducing besides immobilizing agent. The attribute of iron nanoparticles was studied by using UV-VIS spectroscopy SEM and XRD. The XRD spectrum of the iron nanoparticles established the presence of elemental copper signal. Green synthesized iron nanoparticle manifests the zone of inhibition against isolated human pathogenic (Streptococcus species, Bacillus species, Staphylococcus species, Klebsiella species and E. coli) bacteria. The analytical chassis contains the flower pigment betalain the natural food dye resources can efficiently use in the production of iron nanoparticle and it could be utilized in various fields in therapeutics and nanotechnology.
 Keywords: Nanoparticles, Mirabilis jalapa, UV-VIS spectroscopy, SEM- XRD.

Using a B-Phycoerythrin Extract as a Natural Colorant: Application in Milk-Based Products.

Nowadays, there is a growing interest in finding new coloring molecules of natural origin that can increase and diversify the offer of natural food dyes already present in the market. In the present work, a B-phycoerythrin extract from the microalgae Porphyridium cruentum was tested as a food colorant in milk-based products. Using spectroscopy and colorimetry, the extract was characterized and gave evidence of good properties and good stability in the pH range between 4.0 and 9.0. Coloring studies were conducted to demonstrate that samples carrying the pink extract could be used for simulating the pink color of marketed milk-based products. The staining factors, representing the amount of pink protein to be added to reproduce the color of strawberry commercial products, ranged between 1.6 mg/L and 49.5 mg/L, being sufficiently low in all samples. Additionally, color stability during a short period of cold storage was studied: it demonstrated that the three tested types of dairy products remained stable throughout the 11-day analysis period with no significant changes. These results prove the potential of the B-phycoerythrin extract as a natural colorant and alternative ingredient to synthetic coloring molecules.

A 90-day oral repeated-dose toxicity study of Monascus Color Y-001 in rats

Monascus Color Y-001, a natural food dye produced from Monascus purpureus fermentation, was administered orally by gavage to male and female SD rats for 90 days at doses of 0 (vehicle: 0.1% Tween 80, 10 mL/kg bw), 100, 300 and 1000 mg/kg/day. During the treatment period, there was no death, and test article effects on clinical signs were limited to reddish feces, soiled perineal region (reddish color) and salivation that were observed in both sexes at 300/1000 mg/kg/day. Prolongation in PT and APTT occurred in males at 1000 mg/kg/day, and the changes were without any evidence suggesting hemorrhage and/or hepatic dysfunction. Treatment-related histopathological findings were noted in thymus, liver and kidney, and were limited to the females at 1000 mg/kg/day. These findings included decreased cellularity in thymus with decreased thymus weights attributed to nonspecific stress, centrilobular hepatocellular hypertrophy with increase of liver weights attributed to adaptive change, and vacuolation of proximal tubules in kidneys accompanied with related parameter changes in urinalysis. From these results, the no-observed-adverse-effect level (NOAEL) was judged to be 300 mg/kg/day both in male and female rats.

Stability limits of a red Carthamin-cellulose complex as a potential food colourant.

This study covers aspects of stability and colouration of Carthamin- a unique red chalcone extracted from Carthamus tinctorius L. Due to its fast degradation in aqueous solutions even at room temperature, Carthamin has no significant use in the food industry. Therefore, obtaining Carthamin in a stable form is of high interest. Comparing UV-Vis spectra of Carthamin solutions and RGB-data of Carthamin-cellulose complex in the wet state showed a predominant formation of stable Carthamin conformation on the cellulose phase. It was determined that the wet Carthamin-cellulose complex acquires a stable and rich magenta colour in the pH range of 1-5. In aqueous suspensions with pH >6, the Carthamin-cellulose complex gets a purple colour, which is absolutely uncharacteristic for pure Carthamin in an aqueous solution. IR spectra indicate the fixation of Carthamin molecules on the cellulose, which presumably causes hindrance of free internal rotation of Carthamin molecules in the cellulose phase. The reduction of water activity in the cellulosic phase represents an additional stabilizing factor. As a result, the Carthamin-cellulose complex withstands heating up to 70 °C for 15 min in the pH range of 2-5, showing up to 90% of stability. These conditions are typical for the preparation of a wide range of food products. High stability in a food-like environment and magenta colour make the Carthamin-cellulose complex a prospective natural food dye.

Determination of Carminic Acid in Foodstuffs and Pharmaceuticals by Microchip Electrophoresis with Photometric Detection

This paper presents a novel miniaturized analytical method for the determination of carminic acid, a natural red food dye, in complex food and pharmaceutical matrices by microchip electrophoresis (MCE) with photometric detection. MCE has become a very attractive microscale separation technique because it offers high-speed, high-throughput, small sample injection volume and low reagents consumption. Fast determination of carminic acid in less than 5 min was achieved on a poly(methyl methacrylate) microchip in anionic separation mode at pH 6. Photometric detector based on light-emitting diode technology was set to a wavelength of 490 nm. Using a sample injection volume of 900 nL, a limit of detection of 69 nmol L−1 was achieved. A wide linear dynamic range over four orders of magnitude (from nmol L−1 to mmol L−1) was observed for peak area. Developed method provided favorable intra- and inter-day repeatability of the migration time (up to 2.5% RSD), as well as the repeatability of the peak area (less than 1.9% RSD), regardless of the sample type. The content of carminic acid was determined in various foodstuffs and pharmaceuticals, such as candies, saffron, non-alcoholic drink, and sore throat lozenges with good recoveries (92.5–104.0%).

Green Cellular Delivery of Copper Nanoparticle from Mirabilis Jalapa Flower Extract and Its Antipathogenic Activity

Bio friendly green modest synthesis of nanoparticles are the present research in the extremity of nanotechnology. This study has been undertaken to explore the determinants of copper nanoparticles from 1 mM CuSO4 solution through profuse concentration of aqueous flower extract of Mirabilis jalapa reducing besides immobilizing agent. The attribute of copper nanoparticles was studied by using UV-VIS spectroscopy SEM and XRD. The XRD spectrum of the copper nanoparticles established the presence of elemental copper signal. Green synthesized copper nanoparticles manifests the zone of inhibition against isolated human pathogenic (Streptococcus species, Bacillus species, Staphylococcus species, Klebsiella species and E. coli) bacteria. The analytical chassis contains the flower pigment betalain the natural food dye resources can efficiently use in the production of copper nanoparticles and it could be utilized in various fields in therapeutical and nanotechnology.

Carrot Anthocyanins Genetics and Genomics: Status and Perspectives to Improve Its Application for the Food Colorant Industry.

Purple or black carrots (Daucus carota ssp. sativus var. atrorubens Alef) are characterized by their dark purple- to black-colored roots, owing their appearance to high anthocyanin concentrations. In recent years, there has been increasing interest in the use of black carrot anthocyanins as natural food dyes. Black carrot roots contain large quantities of mono-acylated anthocyanins, which impart a measure of heat-, light- and pH-stability, enhancing the color-stability of food products over their shelf-life. The genetic pathway controlling anthocyanin biosynthesis appears well conserved among land plants; however, different variants of anthocyanin-related genes between cultivars results in tissue-specific accumulations of purple pigments. Thus, broad genetic variations of anthocyanin profile, and tissue-specific distributions in carrot tissues and organs, can be observed, and the ratio of acylated to non-acylated anthocyanins varies significantly in the purple carrot germplasm. Additionally, anthocyanins synthesis can also be influenced by a wide range of external factors, such as abiotic stressors and/or chemical elicitors, directly affecting the anthocyanin yield and stability potential in food and beverage applications. In this study, we critically review and discuss the current knowledge on anthocyanin diversity, genetics and the molecular mechanisms controlling anthocyanin accumulation in carrots. We also provide a view of the current knowledge gaps and advancement needs as regards developing and applying innovative molecular tools to improve the yield, product performance and stability of carrot anthocyanin for use as a natural food colorant.

Colour stability and antioxidant activity of C-phycocyanin-added ice creams after in vitro digestion

C-phycocyanin (C-PC) is a protein with bioactive properties, which is found mainly in cyanobacteria and that is used as a natural food dye. Even though it is extensively studied, few authors have reported C-PC’s colour stability and antioxidant activity when applied to food matrices. Therefore, the aim of this research was to evaluate the colour stability over time and the antioxidant capacity of a food grade C-PC extract applied to milk-based ice creams. The C-PC-added ice creams showed insignificant colour loss during 182 d. Regarding antioxidant activity, the C-PC-added ice creams presented low ABTS●+ and peroxyl radicals scavenging capacities before in vitro simulated digestion. However, after in vitro digestion, the ice creams with C-PC extract addition showed antioxidant capacities of 134.63 ± 15.68 and 1425.19 ± 54.93 μmolTE.g−1 by the ORAC and ABTS methods, values 2- and 13-fold higher than the achieved by the controls, respectively. Thus, the results demonstrate that C-PC extract can be applied as a stable blue dye in ice creams and highlight the increased antioxidant activity of the C-PC-added products after in vitro simulated digestion, which can encourage the formulation of food products that attract consumers’ attention for both their colour and biological activities.

Chia seed mucilage as a potential encapsulating agent of a natural food dye

Chia mucilage is a product with high emulsifying capacity, being a potential encapsulating agent of food ingredients microencapsulated. The objective of this paper was to evaluate the chia mucilage as encapsulating agent of the natural beet dye, in combination with maltodextrin and arabic gum (at 10 and 15% of concentration), in spray drying microencapsulation. The mucilage used in the study was obtained by freeze drying and by drying in oven at 50 °C. Moisture, dye retention capacity, hygroscopicity, yield, solubility, color and morphology of the microcapsules were characterized. The effect of pH and temperature of the medium on the aqueous dispersion stability of the samples was also evaluated. The microcapsules formulated with chia mucilage and maltodextrin showed the highest retention capacity of betacyanin, especially the sample formulated with freeze dried chia mucilage. This result about thermal stability study and in the pH stability study, the results were promising.

Cyanidin based anthocyanin biosynthesis in orange carrot is restored by expression of AmRosea1 and AmDelila, MYB and bHLH transcription factors.

The simultaneous expression of AmRosea1 and AmDelila transcription factors from snapdragon can activate the anthocyanin pathway in orange carrots, leading to the synthesis and accumulation of anthocyanins in the taproots. Anthocyanins are phenolic compounds produced in various parts of plants. They are used as natural food dyes and are reported as beneficial antioxidants for humans. Black carrot is an important source for anthocyanins; however, the reason for the lack of anthocyanin production in the orange carrot is unknown. Anthocyanins are synthesized by a specific branch of the phenylpropanoid pathway that has previously been reported to be activated by a triad of R2R3-MYB, basic helix-loop helix (bHLH) and WD40 transcription factors (TFs). In the current study, orange carrots were turned purple by simultaneous expression of R2R3-MYB and bHLH TFs, i.e. AmRosea1 and AmDelila from snapdragon (Antirrhinum majus). Simultaneous transgenic expression of the TFs under a constitutive promoter in the orange carrot cultivar 'Danvers 126' lead to consistent upregulation of anthocyanin-related biosynthetic genes and significant accumulation of anthocyanins in leaves, stems and taproots. Highest overall content of soluble anthocyanins in the taproot among the transformants amounted to 44.38mgg-1 dry weight. The anthocyanin profile of the transformants were significantly different from the profile in the reference black carrot 'Deep Purple'. The main anthocyanins present in the transformed taproots were cyanidin 3-xylosyl(sinapoylglucosyl)galactoside, whereas the main anthocyanin present in Deep Purple was cyanidin 3-xylosyl(feruloylglucosyl)galactoside. This study confirms the presence of the necessary biosynthetic genes in orange carrots for production of anthocyanins and demonstrates the absence of suitable R2R3-MYB and bHLH TFs for stimulating anthocyanin biosynthesis in the orange carrot.

ENVIRONMENTAL AND GEOGRAPHIC STUDY OF BETANIN ACCUMULATION IN PROMISING RED BEET ACCESSIONS FROM THE VIR COLLECTION

Background. Table beet (Beta vulgaris L.) is a source of ‘betanin’, a natural food dye known as food additive E-162. The VIR collection holds a large diversity of red beet accessions. It is the base for obtaining source material to breed cultivars with high betanin content.Materials and methods. In the framework of this study, which lasted from 2015 to 2018, a group of 29 accessions identified during the screening was analyzed. The pigment was assessed at the laboratory of the ECO RESOURCE Joint-Stock Company using Spectrophotometer SF-2000. Field experiments were performed according to VIR’s guidelines in 2015–2017 at Pushkin and Pavlovsk Laboratories of VIR, Volgograd Experiment Station of VIR, and Maikop Experiment Station of VIR.Results. Environmental and geographic tests demonstrated that the ability to accumulate the pigment was variable among the red beet accessions, and its concentrations were notably different. The research showed that accumulation of betanin is primarily associated with agroclimatic growing conditions. The dynamics of pigment accumulation can be both positive and negative. The optimal zone for growing the studied accession is Leningrad Province, where the highest content of betanin was observed. Mid-ripening and cold-resistant old landraces were a reference point in the search for the desired genotypes.Conclusion. The process of pigment accumulation is extremely responsive to weather conditions, soil water balance, and watering uniformity. The negative impact of these factors would smooth down the crop’s varietal polymorphism. Diseases and insect pests have led to slowing and stopping the accumulation of betanin. As a result of the comprehensive agroecological study of prototypes, promising accessions were identified and recommended for cultivation in Leningrad Province with the aim of betanin production.

Valorization of Euterpe edulis Mart. agroindustrial residues (pomace and seeds) as sources of unconventional starch and bioactive compounds.

Juçara fruit pomace is one of the most abundant byproducts of the pulp-making process, generally discarded despite their attractive nutritional content. In this sense, this study aimed to investigate the potential of juçara fruit pomace as an alternative source of starch and natural dyes. Starch extracted from juçara seed (JS) was characterized in approximate composition, crystallinity, thermal profile, morphology, and equilibrium moisture data. Total phenolic content, anthocyanins content, and in vitro antioxidant capacity were assessed for the juçara seedless pomace (JSP). JSP is rich in monomeric anthocyanins (7.19 to 7.23 mg cyanidin 3-O-glycoside/g dry matter [dm]), presents high antioxidant potential, elevated dietary fibers (72.7% dm), considerable amount of lipids (12.8% dm), low protein content, and ash traces. JS is a rich carbon source (76.91% fibers [dm]; 12.21% amylaceous reserve). Being high in carbohydrates, mainly starch, it can be classified as high starch content flour (juçara seed starch-flour [JSS-F]). JSS-F presented B-type crystallinity and conventional starch-like thermal stability. JSS-F exhibited type III sorption isotherm behavior and the Gugghenheim-Anderson-DeBoer model adequately represented the moisture equilibrium data. As a nutritive source of bioactive compounds and starch, juçara pomace should be regarded as a coproduct to be explored as an alternative natural ingredient to food, pharmaceutical, and chemical industries. PRACTICAL APPLICATION: Juçara agroindustrial residues (pomace and seeds) are a promising source of antioxidants and unconventional starch, which are usually discarded after depulping, representing approximately 74% of the fruits. Juçara pomace can be used to produce flour with marketing potential due to their functional properties and nutritional value. This flour can be incorporated directly into formulations or be used in extraction processes to obtain components of interest, for example, anthocyanins, to be used as a natural food dye. Starch can be extracted from juçara seeds, presenting adequate technological properties for partial replacement of conventional starches.

Economic efficiency of the raw materials production for obtaining a natural food dye from Amaranth

The paper presents the economic results of the raw materials production of fthe ood red-violet dye, enriched with antioxidants from the leaves of two varieties of amaranth (Valentina, Don Pedro) breeding of the Federal Scientific Center for Vegetable Growing (Russia). The amaranth plant leaves are used both as a raw material for the production of food-grade natural dye for coloring confectionery products, beverages, and so can be used as part of salads, soups, sauces, enriching them with biologically active substances (in particular, ascorbic acid and phenolic compounds), giving them both original taste and color. The article analyzes the economic efficiency of growing amaranth plants in an open and protected ground, depending on additional mineral fertilizer to obtain a natural food dye. Calculated in prices of 2018, the economic efficiency indicators for both products and resources proved to be satisfactory. Costs per hectare amounted to 77 thousand rubles for cultivation in open ground conditions and 225 thousand rubles for cultivation in a film greenhouse. The cost of raw materials varied from 550 to 880 rubles per kilogram under these conditions. The gross profit ranged from 15 to 125 rubles/ha, profitability ranged from 14 to 81%.

Effect of various factors on extraction efficiency of total anthocyanins from Butterfly pea (Clitoria ternatea L. Flowers) in Southern Vietnam

Nowadays, anthocyanins have become an interesting topic of much scientific research and act as potential sources of eco-friendly natural food dyes and their helpful effects on human health.. The purpose of the present article was to apply conventional extraction methods of pigments from Butterfly pea (Clitoria ternatea L.Flowers) in Southern Vietnam were tested to extract anthocyanins. The effects of various factors, including the solvent concentration, extraction time, temperature, and solvent/material ratio on the extraction total anthocyanins from Butterfly pea were investigated. In this study, the concentration of monomeric anthocyanins was completed by the spectrophotometry pH differential method.The highest recovered anthocyanin level was achieved with 50 % ethanol (143.49 mg/L), while the lowest one was obtained with water (90.9 mg/L). The extraction yield was significantly affected by temperature and the excellent condition was 60°C. The extraction yield raised with increasing of solvent/material ratio until equilibrium has arrived at the optimal ratio of 25:1 (mL/g). The extraction yield increased first and then decreased with an extension in time values.

Study of adsorption isotherms and physicochemical characterization of natural food colourants

Abstract Synthetic colourants are widely used for colouring foods. However, their safety has been questioned. Due to this limitation and the global trend of consuming healthy foods, the industry is faced with the need to replace artificial colourings, which has given rise to a growing interest in colourants from natural sources. Thus, this work obtained the moisture adsorption isotherms of the natural food dyes of anthocyanins, betalains and curcumin and evaluated the humidity, water activity (aw), hygroscopicity, colour and antioxidant capacity in vitro. Isotherms were determined by the static gravimetric method with saturated salt solutions (LiCl. H2O, MgCl2.6H 2O, Mg(NO3)2.6H2O, NaCl, KCl and K2 SO4) at 25 °C. Experimental data were adjusted by GAB, BET, Halsey, Oswin and Henderson models. All models, except Henderson's for Curcumin, fitted the data and BET was used to represent the moisture adsorption isotherm. All the isotherms were type sigmoidal, characteristic of most foods. The observed water content (<0.3%) and a w (<0.03) can be considered favourable to stability. Colour analysis indicated a high colouring strength and the antioxidant capacity suggested that, in addition to representing a source of colour in food products, natural dyes may have an additional function, with possible health benefits.

Routes to independent vessel networks

Biomedicine In air-breathing vertebrates, the circulatory and pulmonary systems contain separate networks of channels that intertwine but do not intersect with each other. Recreating such structures within cell-compatible materials has been a major challenge; even a single vasculature system can be a burden to create. Grigoryan et al. show that natural and synthetic food dyes can be used as photoabsorbers that enable stereolithographic production of hydrogels containing intricate and functional vascular architectures. Using this approach, they demonstrate functional vascular topologies for studies of fluid mixers, valves, intervascular transport, nutrient delivery, and host engraftment. Science , this issue p. [458][1] [1]: /lookup/doi/10.1126/science.aav9750