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In most birds, red feather color is linked to diet and attributed to carotenoids contained in plants and fruits. In the red crown feathers of the Ruby-crowned Kinglet (Regulus calendula), a new biopigment was identified based on carminic acid, the main coloring compound of cochineal (Dactylopius coccus) and other scale insects. This has revealed a potential new class of carminic acid-based biopigments, not previously identified in feathers. In this research, red crown feathers of a Ruby-crowned Kinglet were analyzed by surface-enhanced Raman scattering (SERS) employing synthesized silver star-shaped colloids as the nanoplasmonic platform. Results indicated peaks at 450, 670, 1290-1312, 1355, 1410, 1570, 1620 cm-1 in the feather SERS spectra characteristic of carminic acid. SERS has proven to be an extremely sensitive, non-destructive technique for the identification of different feather biopigments, even at trace quantities and in the presence of other predominant coloring substances.

Dactylopius coccus es un insecto de importancia comercial como fuente de un colorante natural denominado ácido carmínico. Para su producción comercial en cautiverio, se ha promovido la cría en cladodios suspendidos a diferentes alturas, en un sistema denominado “nopaloteca”. Sin embargo, se desconoce si su calidad y rendimiento es uniforme en los diferentes niveles. El objetivo de este estudio fue determinar la influencia de la altura del nivel en una “nopaloteca” y el índice de cosecha en la concentración de ácido carmínico (CAC, %) y peso fresco (PF, g) de D. coccus. La crianza del insecto se realizó en una “nopaloteca” de madera (3x3 m), con cuatro niveles de altura (0.5, 1.0, 1.50 y 2 m). Durante el ciclo de cultivo se registró cada día la temperatura, la humedad relativa y la intensidad luminosa. Las hembras adultas se recolectaron en dos etapas del desarrollo: pre y postoviposición. La CAC más alta (19.2%) se obtuvo en 1.0 m de altura, aunque este nivel registró el PF más bajo con 3.5 g por cladodio, que expresa una correlación negativa entre la CAC y el PF. La recolecta en postoviposición generó una CAC superior (18.8%), aunque el PF se redujo. Tanto la humedad relativa (HR) como la iluminación total, pero principalmente la temperatura que incidió en cada nivel, influyeron en la calidad y el rendimiento de D. coccus, aunque de manera diferencial sobre ambos factores, lo cual indica la presencia de límites óptimos de desarrollo. Bajo las condiciones del estudio, el sistema de cría en “nopaloteca” produjo en promedio 4.5 g de cochinilla por cladodio y una CAC de 17.5%. Los niveles evaluados causaron diferencias en rendimiento y calidad, pero sus valores más altos se registraron en los niveles intermedios (1.0 y 1.5 m). El índice de cosecha recomendado para obtener mayor CAC fue la etapa de postoviposición.

In this study, three foodstuffs (surimi, minced meat, and milk) were dyed with carminic acid and carminic aluminum lake. The effects of protein, metal ions, and food additives on the color of carminic acid and carminic aluminum lake were investigated. After being dyed by carminic acid, the colors of surimi, minced meat, and milk were light purple, red, and gray‐green, respectively. When using carminic aluminum lake, surimi and milk were magenta, and minced meat was red. Regarding the carminic acid solution, the presence of myofibrillar protein (MFP), whey protein isolate (WPI), and soy protein isolate (SPI) turned it red by changing the pH, while the presence of casein made it orange. The carminic aluminum lake solution turned magenta in all four cases, which were not affected by protein. The color of carminic acid and carminic aluminum lake was significantly affected by 0.001–0.1 mol/L Fe3+, 0.001–0.1 mol/L Fe2+, 0.001–0.1 mol/L Cu2+, and 0.1 mol/L Ca2+, limiting their application in iron‐, copper‐, and high‐calcium foods. The color of carminic acid was changed to yellow by 0.01%‐1% sodium nitrite, but 0.01%–1% ascorbic acid and 0.01%–0.1% monascus color did not significantly affect the color of either carminic acid or carminic aluminum lake. This paper provides a reference for the application of carminic acid and carminic aluminum lake in food science., Three foodstuffs (surimi, minced meat and milk) were dyed by carminic acid and carminic aluminum lake. The effects of protein, metal ions and food additives on the color of carminic acid and carminic aluminum lake were investigated.This paper provides a reference for the application of carminic acid and carminic aluminum lake in food industry.

Dactylopius opuntiae (Hemiptera: Dactylopiidae) is a key pest of the prickly pear cactus in Mexico where the plant, and its phytophagous community, are native. It is also an introduced pest in Brazil and the Mediterranean basin. Amongst the phytophagous community of prickly pear in Mexico there is also Dactylopius coccus, the cultivated cochineal. This cochineal is used to obtain carminic acid as a natural dye, but it has also been reported as an invasive pest in Ethiopia. The most feasible control option for these insects is biological control, but whether their natural enemies develop well in both species is unknown. The aim of this work was to study the biology of the predator, Laetilia coccidivora (Lepidoptera: Pyralidae), when it was fed either D. opuntiae or D. coccus in the laboratory. The predator completed its development on both species. Carminic acid was at higher concentrations in D. coccus (8–25%) than D. opuntiae (2–5%), and feeding on D. coccus had negative effects on larval duration (16.7 vs. 22.0 days), developmental time (36 vs. 43.2 days) and survival rate of the predator (42.5 vs. 92.4%). Fecundity (22.7 vs. 12.9 eggs per female), net reproductive rate (R0 = 10.1 vs. 5.8) and intrinsic rate of increase (rm = 0.064 vs 0.041) were also diminished when L. coccidivora fed on D. coccus, compared with D. opuntiae. We discuss possible reasons for variation in predator fitness when fed on each prey type.

Significance Microbial degradation of C -glycosides is only reported from human intestinal bacteria. This study isolated a C -glycoside–catabolizing bacteria, Microbacterium sp. 5-2b, from soil and identified a C -glycoside–metabolizing enzyme. Surprisingly, while the metabolic pathway of C -glycoside in the strain was similar to that of an intestinal one, the enzyme named CarA catalyzing the initial step of metabolism was completely different from an enzyme identified from the intestinal microorganism; CarA identified as C -glycoside 3-oxidase for C-glycoside metabolism exhibited amino acid sequence similarity to pyranose oxidase family proteins. This study clarified the structure, function, and distribution of the enzyme involved in C -glycoside catabolism and provides insight into the biogeochemical circulation of C -glycosides in nature.

Carminic acid (CA) extracted from cochineal is widely used in food additives as a natural colorant, and its potential risk to human health makes its detection important. In this work, a layered doubled hydroxide (LDH)–luminol–H2O2 system-based chemiluminescence (CL) platform has been successfully applied for CA sensing. The principle detection consists of two steps: first, LDH adsorbs CA onto the surface via electrostatic attraction; second, CA quenches the CL of the LDH–luminol–H2O2 system via the synergistic effect of CL resonance energy transfer, reduction of reactive oxygen species, and occupation of positively charged centers of brucite-like layers. With this CL approach, 0.5 μM CA is detectable using a CL spectrometer, and the limit of detection is 0.03 μM. This CL system exhibited a linear response to CA in the concentration range from 0.5 to 10 μM. In addition, the practical application of the designed CL sensing system is evaluated with dried pork slice samples.

11 pags., 5 figs., SERS spectroscopy is successfully employed in this work to reveal different components integrating the cochineal colorant employed for dying archaeological textile samples from the Arica Region in North Chile. This analysis was done by in-situ experiments that does not imply the material (colorant and biomolecules) extraction. The spectroscopic analysis of the archaeological textiles by SERS reveals the presence of bands attributed to carminic acid and nucleobases, mainly adenine and guanine. The identification of these biomolecules was also verified in raw cochineal extract and in cochineal dyed replica wool fibers fabricated by us following ancient receipts. The effect of Al on the complexation of carminic acid and other biomolecules was also tested in order to understand the changes induced by the metal interaction on the colorant structure. This study revealed that Al can also complex biomolecules existing in the cochineal extract. In particular, guanine residue seems to interact strongly with the metal, since SERS bands of this residue are enhanced. Furthermore, a theoretical analysis on the interaction of carminic acid and a silver surface was also performed in order to better understand the interaction mechanism between carminic acid and a metal surface that leads to the final SERS spectrum. The results of the present work will be very useful in the identification of different molecules and metal complexes that may be forming part of the cochineal colorant found in archaeological materials., S.S.C., M.C.V. and F.C. acknowledge the i-COOP+2015 Program of CSIC, project COOPB20146. C.S. acknowledges to Conicyt 21150397. F.C. acknowledges Fondecyt project 3150222 and CNE 10-1920 project funded by the Universidad de Playa Ancha (Concurso Regular de Investigación 2018). S.S.C. and F.C. also thanks the MINECO/ FEDER project FIS2017-84318-R.

Carminic acid (CA) and other related compounds have been widely used as dyes in cultural heritage, cosmetics and the food industry. Therefore, the study of their properties upon photoexcitation is particularly important. In this work, the photophysical and photochemical properties of CA, carminic lake and other related pigments in aqueous solutions are revisited. Novel quantitative information regarding the fate of the photoexcited states is provided including the efficiency of reactive oxygen species (ROS) photosensitized production (i.e., singlet oxygen and hydrogen peroxide) as well as the efficiency of nonradiative deactivation pathways. Laser-induced optoacoustic spectroscopy (LIOAS) data revealed that for all the investigated compounds, almost all the absorbed energy is released as prompt heat to the media. This is in agreement with the fact that other deactivation pathways, including fluorescence (ΦF ∼ 10−3–10−5), photochemical degradation (ΦR ∼ 10−4) and/or photosensitized ROS formation (ΦH2O2 < 10−5 and ΦΔ ∼ 0), are negligible or null. In addition, a comprehensive investigation of the photodegradation of CA and lake is herein reported. The influence of different experimental parameters such as irradiation wavelength and oxygen partial pressure was evaluated. UV-vis absorption and fluorescence emission spectroscopy in combination with chemometric data analysis were used to elucidate the relevant aspects of the photodegradation mechanism involved and the spectroscopic features of the photoproducts generated. In aqueous media, CA follows an O2-dependent photochemical degradation when subject to elapsed photoexcitation in the UVB, UVA and visible regions. The photoproduct profile depends on the excitation wavelength giving rise to quite distinctive spectroscopic profiles. With respect to lake, our data suggest that upon photoexcitation, this pigment releases a CA-like chromophore that follows a similar fate to CA.

We present here a novel strategy for textile sample treatment, using galvanic displacement-based substrates, to identify anthraquinone dyes by surface enhanced Raman spectroscopy (SERS). This global procedure of SERS analysis, using several silver microparticles, in particularly those of dendritic shape, formed by reducing silver nitrate with zinc or copper, can be accomplished within 20 min. Compared to the synthesis of standard Lee-Meisel colloids, the preparation of silver dendrites provides a simple, fast and cost-effective route to produce reliable SERS substrates. The most fascinating feature is that the textile fibers analyzed are almost simultaneously covered with the substrates once the galvanic displacement reaction is triggered. This method was successfully applied to discriminating between alizarin and purpurin in a 6th-9th century samite with bird roundels, and carminic acid and laccaic acid in a 1740s chinoiserie brocade. However, as is the case with other silver substrates, the Raman signals of the insect dyes normally overlapped those of the plant dyes in the SERS profiles.

A systematic study of the addition of C-based nucleophiles to fluorinated lactones based on 2-deoxy-2-fluoro-d-pyranoses is disclosed. This high yielding, α-selective process was found to be independent on the nature or configuration [(R)-C(sp3)-F, (S)-C(sp3)-F] of the substituent at C2. Representative, fluorinated analogues of Trehalose, Carminic acid, and the spirocyclic cores of Tofogliflozin and Papulacandin D are also reported. These glycomimics constitute a valuable series of 19F NMR active probes for application in structural biology.

The boron content was determined in 42 different foods consumed in Istanbul, Turkey. Eleven species of fruit, ten species of vegetable, eight species of food of animal origin, four species of grain, two species of nuts, two species of legume, and five other kinds of foods were included to this study. They were analyzed by two methods: Inductively coupled plasma mass spectrometry (ICP-MS) technique and carminic acid assay, and the results of two methods were also compared. Boron concentration in foods ranged between 0.06–37.2 mg/kg. Nuts had the highest boron content while foods of animal origin had the lowest. A strong correlation was found between the results of the carminic acid assay and the ICP-MS technique (p = 0.0001, Pearson correlation coefficient: r = 0.956). Bland Altman analysis also supported this correlation. ICP-MS is one of the most common, reliable, and powerful method for boron determination. The results of our study show that spectrophotometric carminic acid assay can provide similar results to ICP-MS, and the boron content in food materials can be also determined by spectrophotometric method. © 2018, Springer Science+Business Media, LLC, part of Springer Nature. SAG-C-YLP-070317-0092 Funding This work was financially supported by the Marmara University Scientific Research Projects Commission [grant number SAG-C-YLP-070317-0092].

The revival of natural dyes in textiles is gaining popularity due to their sustainable nature. The current study has been undertaken to improve the dyeing behaviors of cochineal-based natur...

Foods must have attractive color, flavor and texture to be acceptable to consumers. Carminic acid (C.I. (1956) 75470; C.I. Natural Red 4; EEC No. E120) is a natural red dye extracted from cochineal, the desiccated bodies of female Dactylopius coccus Costa insects. Carminic acid produce pink shades in candy, confections, chewing gum, concentrated fruit juice, smoked fish, liqueurs and alcoholic cordials, soft drinks, yoghurt, ice cream, tomato ketchup, baked goods, dairy products, jams, jellies, eye shadow, and pill coatings. The impact of the presence of aspartame, citric acid and vitamin C on the spectrophotometric parameters of carminic acid was investigated. These results enabled us to evaluate the possibility of using UV-Vis spectrophotometric method for easily identifying and quantifying carminic acid present in a wide variety of foodstuffs in the presence of additives. It was established that the inves­tigated additives do not affect the position of absorbance maximum of the dye nor cause changes in its intensity. The value of molar absorptivity, ε, at 518 nm was 1265.68 ± 49.90 dm3/mol∙cm. The calculated value is necessary for the quantitative spectrophotometric determination of carminic acid food dye. The FT IR spectra of the dye was also recorded.

We evaluated the skin sensitizing potential of 10 natural organic chemicals, or their derivatives, which are included in foods and/or skin products, using a modified local lymph node assay (LLNA), with an elicitation phase (LLNA:DAE). The following compounds were tested: carminic acid, esculetin, 4-methyl esculetin, coumarin, quercetin, curcumin, naringenin, chlorogenic acid, isoscopoletin, and shikonin. Esculetin, 4-methyl esculetin, isoscopoletin, and shikonin yielded positive results. In particular, shikonin at a very low concentration (0.05%) induced an elicitation response. In conclusion, four of the 10 natural organic chemicals tested had a skin sensitization potential, with shikonin producing serious reaction even at a very low concentration.

In this work, we improved the adsorption capacity of Opuntia ficus-indica fruit peels (OFIFP) by graft-copolymerization using gamma radiation. Acrylic acid (AA) and 4-vinylpyridine (4VP) were grafted onto OFIFP to yield the adsorbents OFIFP-g-polyAA, OFIFP-g-(polyAA-co-4VP), and OFIFP-g-poly(4VP-co-AA). The viability of employing these adsorbents in the removal of textile dyes was analysed constructing adsorption isotherms for methylene blue, malachite green, methyl orange, and carminic acid. The adsorption of cationic fit Langmuir's model well, but Freundlich's model better described the adsorption of anionic dyes. Graft-copolymerization improved the adsorption capacity of OFIFW for cationic dyes by 25%. Furthermore, the removal percentage for disperse orange dye within wastewater increased by 400% using OFIFP-g-(polyAA-co-4VP). Then, graft-polymerization using gamma radiation is a suitable tool to improve the adsorption capacity of lignocellulosic adsorbents.

We have developed a colorimetric chemosensor for the selective and sensitive detection of Cys based on the complex (CA-2Pb2+) between a commercially available natural organic dye, carminic acid (CA) and Pb2+ in pure aqueous solution at physiological pH. The addition of Cys to the CA-2Pb2+ solution resulted in a distinct color change from purple to red together with a remarkable absorption spectral change by the restoration of CA through a displacement mechanism with formation of the Cys-Pb2+ complex, whereas other amino acids and glutathione induce no or minimal spectral and color changes. Moreover, the other amino acids and GSH do not affect the detection ability of CA-2Pb2+ for Cys. The reversibility even through several cycles was established for practical applications. The results indicate that CA-2Pb2+ may be useful as a potential colorimetric and naked-eye chemosensor for Cys over Hcy and GSH in aqueous solution.

A HPLC method coupled with diode array detector was developed and validated for the quantitation of alizarin, apigenin, carminic acid, curcumin, ellagic acid, emodin, fisetin, kaempferide, kaempferol, kermesic acid, morin, purpurin, quercetin and sulfuretin which are components of several natural dyes. 1- Hydroxyanthraquinone was selected as internal standard. The compounds were separated under gradient elution on a RP-column (Altima C18, 250 mm x 3.0 mm i.d., 5 μm) with a mobile phase consisting of solvent A: H2O + 0.1% (v/v) trifluoroacetic acid and solvent B: acetonitrile + 0.1% (v/v) trifluoroacetic acid. The method was validated in terms of linearity, limits of detection and quantitation, accuracy, precision, ruggedness and robustness and applied to the analysis of silk dyed with buckthorn (Rhamnus trees), cochineal (Dactylopius coccus Costa), madder (Rubia tinctorum L.), turmeric (Curcuma longa L.) and young fustic (Cotinus coggygria Scop). Furthermore, dyed silk samples were subjected to artificially accelerated ageing conditions induced by UV radiation. The effect of the latter on the quantities of the aforementioned compounds was monitored, except for apigenin, kermesic acid and morin.

El ácido carmínico es una sustancia que probablemente funciona como protección ante la depredación. Su concentración difiere entre Dactylopius coccus y D. opuntiae. Entonces, planteamos la hipótesis de que un depredador específico, el coccinélido Hyperaspis trifurcata, tendría una preferencia alimentaria por la especie con menor concentración de ácido carmínico. Para comprobar esta hipótesis se realizaron pruebas de elección con ambas especies en condiciones de laboratorio (25 ± 2 °C, 50 ± 20 % HR, y 12:12 h L:O). En la primera prueba, el depredador tuvo opción de alimentarse de ninfas de primer ínstar de ambas especies de presas, y en el segundo de hembras grávidas. H. trifurcata consumió ninfas de primer ínstar de ambas especies, y no mostró preferencia por alguna de ellas. En ese estado de desarrollo la concentración de ácido carmínico entre especies fue similar. Sin embargo, H. trifurcata prefirió alimentarse de hembras grávidas de D. opuntiae con una concentración de ácido carmínico de 3 %, mientras que dicho contenido fue de 23 % en D. coccus. Nuestros resultados apoyan la hipótesis de que H. trifurcata prefiere alimentarse de D. opuntiae en lugar de D. coccus debido a la concentración de ácido carmínico, o de algunos de sus precursores metabólicos

International audience; Hybrid pigments based on carminic acid (CA) stabilized by clay minerals have been prepared. Three different pathways were used: CA@saponite; CA@Al-pillared saponite; and hydrogels of saponite-CA or montmorillonite-CA covered by polyorganosilane (POS). Pigments were characterized by a set of different techniques including X-Ray diffraction (XRD), transmission electron microscopy (TEM), infrared spectroscopy (FTIR), solid state nuclear magnetic resonance (NMR) and time-resolved fluorescence (TRF) spectroscopies. The color parameters, i.e., L*a*b*, were measured. In addition, the photostability of the samples under visible light was evaluated. The results showed that CA@PilSap presented a greater stability compared to CA@Saponite. The pigments obtained from hydrogels presented the greatest light stability due to the coverage with POS that acts as a protective layer.

The nature of the pigments or dyes used to dye the first Portuguese postage stamps has remained unknown until now. In this work, a study has been made of the inks used for red, rose, purple and orange colors in a selected number of Portuguese postage stamps from the period 1857 to 1909. This is based on analysis involving a variety of techniques (X-ray fluorescence, UV-Vis spectroscopy, HPLC-MS/HPLC-DAD, steady and time resolved fluorescence). It was found that the inks included, among others, the inorganic pigments cinnabar (HgS), lead oxide (Pb3O4) and chromate (PbCrO4), lead sulphide (PbS), and the organic compounds carminic acid and Eosin Y. The study demonstrated a non-destructive analysis method for identification of two molecules of color involving the UV-Vis (for carminic acid and Eosin Y) and fluorescence spectra, together with quantum yields and lifetimes (for Eosin Y).

Dried bodies of the female insect Dactylopius coccus Costa were extracted using various extraction solvents. Whereas the amount of extracted carminic acid was between 4 and 24 % of insect material, 4-aminocarminic acid was detected in the extracts in only in low amounts of about 0.1 % of insect material. Compared to ratios of 4-aminocarminic acid to carminic acid, which had been reported to be present in some food additive and beverage samples, ratios in the insect extracts were very low (between 1:211 and 1:154, w/w). However, mixing carminic acid and ammonium hydroxide resulted in formation of significant amounts of 4-aminocarminic acid. Depending on the molar ratio of carminic acid to ammonia, the ratio of 4-aminocarminic acid to carminic acid was up to 1:1.2 (w/w). Spontaneous formation of 4-aminocarminic acid leading to a false positive result was also observed for the analysis of a ketchup sample when ammonia was used during sample preparation.

The commercially available natural organic dye, carminic acid (CA), an anthraquinone derivative bearing hydroxyl and carboxyl groups as recognition sites was found to be a colorimetric probe for Pb2+ in perfect aqueous solution under neutral conditions with specific selectivity and high sensitivity. Upon addition of Pb2+, the absorption maximum of CA showed a large red shift, and the resulted color change from red to purple could be easily identified even by the naked eye. The chemical stoichiometric ratio between CA and Pb2+ was determined to be 1:2 through Job plot, Pb2+ titration, and kinetic experiments. Moreover, other environmental relevant metal ions induced no or minimal spectral and color changes. The reversibility of Pb2+ to CA with EDTA even through several cycles was established for practical applications. The results indicated that CA can be a good candidate for simple, convenient and reversible colorimetric detection of Pb2+ in aqueous solution even though it was hard to be applied to determine Pb2+ on the water testing by US EPA.

Carminic acid (CA), a member of natural dyes, is well known for its good stability in a variety of foods such as candies, drinks, and fruits. However, it has never been authorized as a food additive in meat products. In order to detect CA with high sensitivity and specificity, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) has been developed. A high-titer polyclonal antibody (Pab) against CA was obtained after the immunization of New Zealand white rabbits with conjugate of CA coupling with BSA. Several physicochemical factors including pH value, ionic strength, and organic solvent were tested, and it was observed that the ELISA working solution was pH 7.4 PBS buffer containing 50 mmol L−1 Na+. Under the optimal conditions, 50% inhibitive concentration (IC50) of CA was 95.2 ng mL−1 and the limit of detection (LOD) was 1 ng mL−1. Cross-reactivity of the Pab toward carmine was 108.7%, and no response was found with other four edible colorants. The spiked meat samples were detected by ic-ELISA with intra- and inter-assay recovery ranges of 79.1–103.1 and 81.6–98.8%, respectively. Finally, the results for the fortified food samples were further confirmed by high-performance liquid chromatography (HPLC) with a high correlation coefficient of 0.927, which demonstrated that the method in the study was sensitive enough for the quantification of CA in meat products.

The synthesis of hybrid pigments was made from combination of γ-Al2O3 and some organic chromophores such as carminic acid, alizarin, purpurin, curcumin, fluorescein and betacyanins. The γ-Al2O3 was obtained through sol-gel synthesis with 2-propanol and aluminium tri-sec-butoxide (ATB). This article presents some spectroscopic evidences related to the formation of aluminium complexes between coordinative unsaturated sites (CUS) of aluminium and some organic groups (carboxylic acid, quaternary ammonium and β-keto enol) present in the chromophores structure. The physicochemical properties upcoming from a spectroscopic analysis point out that these materials can be applied in the design of new materials with potential uses in artworks and in the field of cultural heritage.

We developed and validated an interference free microfluidic instrument for rapid determination of boron concentration in produced water using the carminic acid assay. Interferences from other species are eliminated by controlling crucial aspects of the kinetics and thermodynamics of the assay. The use of a microfluidic mixer improves the reaction kinetics by reducing the diffusion time. The high surface-to-volume characteristic of microchannels efficiently dissipates the heat generated by the exothermic reaction of the carminic acid with water. We incorporate a 6.5 bar back pressure element, which offsets the onset of calcium sulfate precipitation and hydrochloric acid outgassing that often disturb optical measurement for the assay when performed at atmospheric pressure. The analyzer has a measurement rate of 1 sample per min, a precision of 5%, a limit of detection of 0.16 mg L−1 at 615 nm, and a measurement range of 0–420 mg L−1. The instrument accurately measured ten water samples that were representative of fluids encountered in the oilfield when compared to ICP-MS measurements. The fast measurement rate of the instrument enables near real-time decision of the fate of produced water in the oilfield.

Cochineal extract prepared from the scale insect Dactylopus coccus (American cochineal) has been used as a natural red dye for food, cosmetics, and pharmaceuticals. The major pigment in cochineal extract is carminic acid (CA), an anthraquinone glucoside, and several minor pigments have been previously reported. Our investigation aimed at establishing the safety of cochineal dye products using ultra performance liquid chromatography-photo diode array-electrospray ionization-time of flight (UPLC-PDA-ESI-TOF)/MS found an unknown minor pigment, spiroketalcarminic acid (1), in three commercial cochineal extract samples; cochineal extract used in food additives, carmine that is an aluminum salt of cochineal extract used as natural dye, and a research reagent of CA. The purification of 1 from cochineal extract involved sequential chromatographic techniques, including preparative reversed-phase HPLC. Two dimensional (2D)-NMR and mass analyses established the structure of 1 to be a novel anthraquinone with an unusual 6,5-spiroketal system instead of the C-glucosyl moiety of CA. The absolute stereochemistry of the spiroketal moiety in 1 was determined by nuclear Overhauser effect spectroscopy (NOESY) correlations and optical rotation. No data corresponding to 1 had previously been reported for extracts of dried cochineal insects and traditional art products dyed with cochineal extract, indicating that 1 is likely produced during the preparation of commercial cochineal extract.

Lac dye and cochineal extract contain laccaic acids and carminic acid as the main pigments, respectively. Both laccaic acids and carminic acid are anthraquinone derivatives. 4-Aminocarminic acid (acid-stable carmine), an illegal colorant, has been detected in several processed foods. 4-Aminocarminic acid is obtained by heating cochineal extract (carminic acid) in ammonia solution. We attempted to prepare ammonia-treated lac dye and to identify the structures of the main pigment components. Ammonia-treated lac dye showed acid stability similar to that of 4-aminocarminic acid. The structures of the main pigments in ammonia-treated lac dye were analyzed using LC/MS. One of the main pigments was isolated and identified as 4-aminolaccaic acid C using various NMR techniques, including 2D-INADEQUATE. These results indicated that ammonia-treatment of lac dye results in the generation of 4-aminolaccaic acids.

Carminic acid (CA) can serve as a redox mediator and influence the electron transfer process. CA dosages of 0–5 mg/L were added to anaerobic ammonia oxidation (anammox) biomass. The results illustrated that CA not only reduced the inorganic nitrogen removal efficiency, but also decreased the nitrogen removal rate. The deterioration of nitrogen removal performance was due to the excess production of nitrate-nitrogen. The concentration of extracellular polymeric substances showed a decrease together with a decline in N-acyl-homoserine lactones release. CA addition decreased the activity of anammox bacteria while increasing the nitrifying potential. Quantitative reverse transcription polymerase chain reaction showed a decrease in anammox functional genes (nirS, hzo, and hzsB) and promotion of the expression of the nxrB gene, which corresponded with a decrease in anammox bacteria activity and the improvement of nitrifying potential. As a result, CA should not be added to anammox biomass.

The shift from artificial to natural ingredients is a rising trend in the food industry. However, natural coloring agents tend to be less stable than their synthetic counterparts when exposed to light, air, changes in pH, and heat. This study compares the photostability of three organic red dyes, Red 40 (allura red AC), betanin and carminic acid, in aqueous and soft drink solutions. The degradation, traced through absorbance spectroscopy, is well fit to first-order kinetics. Two distinct timescales are observed in aqueous solution but only a single, faster decay in the soft drink matrix. Betanin is the least stable dye in both solvent environments and Red 40 exhibits the greatest destabilization in the soft drink solution. Anoxia has different impacts dependent upon both the dye and solvent system. The analysis provides further insight into the degradation mechanisms for these different red dyes and the role of environment on their photostability.

Natural colors particularly animal-based colorants are employed in the field of cosmetics, food, and flavors and also gaining popularity in textiles, due to their soothing nature. In this study, the microwave-assisted extraction of colorant from cochineal insects for dyeing of bio-mordanted silk has been carried out. Acidic, methanolic, and acidified methanol solubilized media were used to extract the natural colorant from cochineal under microwave irradiation for 1–6 min. Bio-mordants have been employed at optimized conditions to make the process greener and sustainable. It is found that acid solubilized extract of pH 4, employed at 55 °C for 55 min containing 5 g/100 mL of Glauber’s salt as exhausting agent has given high color strength onto microwave-treated silk fabric. Suggested ISO standards for colorfastness have revealed that bio-mordants have given excellent color depth and excellent rating of fastness properties, compared with chemical mordants used. It is found that microwave treatment has not only improved the dyeing behavior of colorant extracted from cochineal in acid solubilized medium but also enhanced the color characteristics onto bio-mordanted silk fabric.

Chemical ionization of organic compounds with negligible vapor pressures (VP) is achieved at atmospheric pressure when the proximal sample is exposed to corona discharge. The vapor-phase analyte is produced through a reactive olfaction process, which is determined to include electrostatic charge induction in the proximal condensed-phase sample, resulting in the liberation of free particles. With no requirement for physical contact, a new contained nano-atmospheric pressure chemical ionization (nAPCI) source was developed that allowed direct mass spectrometry analysis of complex mixtures at a sample consumption rate less than nmol/min. The contained nAPCI source was applied to analyze a wide range of samples including the detection of 1 ng/mL cocaine in serum and 200 pg/mL caffeine in raw urine, as well as the differentiation of chemical composition of perfumes and beverages. Polar (e.g., carminic acid; estimated VP 5.1 × 10-25 kPa) and nonpolar (e.g., vitamin D2; VP 8.5 × 10-11 kPa) compounds were successfully ionized by the contained nAPCI ion source under ambient conditions, with the corresponding ion types of 78 other organic compounds characterized.

In the present study, the novel calcined CuAl-layered double hydroxides/carbon nanotubes/polyvinylidene fluoride (CuAl-CLDH/CNT/PVDF400) composites are fabricated via a hydrothermal, casting and calcination method. The as-fabricated CuAl-CLDH/CNT/PVDF400 composite was characterized by FE-SEM, EDS element mapping, XRD, FTIR, BET and BJH. The prepared composite applied as adsorbents to remove Carminic acid (CA) as an anionic dye from colored wastewater. The adsorption efficiency of CA by CuAl-CLDH/CNT/PVDF400 adsorbent is higher than that of the other calcined and uncalcined composites. The obtained composite in aqueous solutions applied for CA removal was investigated based on central composite design (CCD) matrix in batch mode. The adsorption kinetics of CA on obtained composite followed by intra-particle diffusion model that indicated that the limiting step in adsorption could be controlled by the diffusion process. The maximum adsorption capacity by Langmuir isotherm reached 33.44 mg g−1. Thermodynamic study represented that the adsorption of CA on to the obtained composite was an endothermic process.

Carminic acid is the main coloring component of cochineal (a red organic dye extracted from female bodies of Dactylopius coccus). The utilization of the dye in specific painting techniques is determined by the addition of suitable binders, which influence the light and thermal stability of the color layer. In this work, the influence of some plant-based binders (maize starch, gum arabic) and some binders of animal origin (egg albumen, gelatin) on light and thermal stability of model systems with carminic acid was studied. As colorants, two available commercial colorants were used – the carminic acid and Carmine Naccarat, and two colorants prepared in the laboratory – the cochineal carmine and cochineal. The color layers were subjected to accelerated light and thermal aging. For characterization of the color layers and changes of their properties during accelerated aging the spectral methods (ATR-FTIR, VIS) and colorimetry were used. Comparison of the influence of the binders on light stability of the color layers showed the layers with albumen were the least stable, whereas the layers with gum arabic were the most stable. No significant color changes were detected during thermal aging.

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&minus, 1 was achieved. A wide linear dynamic range over four orders of magnitude (from nmol L&minus, 1 to mmol L&minus, 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&ndash, 104.0%).

This work deals with the carminic acid stabilization in a silica matrix and the study of structural properties. Results indicate that silica provides exceptional thermal stability to the carminic dye because its functional properties remain without significant changes up to 500 °C. The embedded carminic acid changes the crystallization behavior of silica. The carminic acid extracted from Mexican cochineal was firstly stabilized with sucrose and after embedded in a silica matrix using the sol-gel method. The structural behavior was analyzed in function of temperature from RT to 900 °C. The resulting properties were studied using X-ray diffraction and FT-IR spectroscopy. Interaction of carminic acid with silica reduces the formation temperature of tridymite and cristobalite. Amorphous tridymite was detected at 400 °C, semicrystalline tridymite at 700 °C, α-cristobalite at 800 °C, and β-cristobalite at 900 °C. The improved stability of carminic acid results from its interaction with the silica, which also modifies the silica crystallization kinetics.

Carminic acid and its metal derivatives have been used widely as pigments for fabrics and art, and more recently as a colorant for food. An undergraduate teaching laboratory is described in which students are instructed to design and execute experimental studies to obtain detailed information about the electronic structure, metal complex formation, redox properties, and photochemical stability of extracted carminic acid. The lab maintains room for student innovation and is well-suited to upper-level undergraduates in an advanced spectroscopy lab. Students are invited to apply knowledge previously gained through highly directed experiments to the analysis of an unfamiliar, complex, and relevant problem. The laboratory lends itself to flexibility in implementation but is designed to deepen students’ understanding of UV–vis spectroscopy, fluorescence spectroscopy, IR spectroscopy, electrochemistry, pH and metal spectrophotometric titrations, and experimental determination of the kinetic behavior of UV-induce...

Hybrid materials based on one organic dye, the carminic acid, and montmorillonite have been prepared and characterized by a multi-technical approach. Aluminum and tin II cations were used in the experimental mixtures in order to have a chelating effect with the carminic acid. X-Ray diffraction patterns (XRD) did not highlight any intercalation of the organic molecule in the interlayer space, a result confirmed by transmission electron microscopy (TEM) micrographs. The fixation of the organic molecules on the phyllosilicates was then investigated by 13 C solid state nuclear magnetic resonance (NMR) and time resolved fluorescence spectroscopies. The spectra showed the role that the ketone and catechol functions of the dye played for its fixation and stressed on the decrease of its mobility when the lake pigment was formed. The role of the clay edges and/or surface was highlighted by this set of experimental data.

The performance of natural dyes in dye-sensitized solar cells is usually worse than that of purpose-built organic dyes. Here, we set out to investigate the underlying origins. Two natural dyes, carminic acid and santalin, were selected as potential sensitizers for dye-sensitized solar cells. They were compared to a state-of-the-art organic sensitizer, LEG4, in devices using relatively thin (5 μm), transparent mesoporous TiO2 electrodes and iodide/triiodide redox electrolyte in the low-volatile solvent 3-methoxypropionitrile. All dyes adsorbed well onto mesoporous TiO2 electrodes, giving it bright red colors. The power conversion efficiency of the natural dyes, about 0.5%, was poor compared to that of LEG4 under identical conditions (5.6%), due to both lower open circuit potentials and photocurrent densities. The origin of low efficiencies was investigated using a wide range of experimental techniques, such as (spectro)electrochemistry, ns-laser transient absorption spectroscopy and transient photocurrent and photovoltage measurements. The kinetics for regeneration of the oxidized natural dyes by iodide was found to about ten times slower than that of LEG4. This is probably due to the lower driving force for this reaction. Significant electron recombination to oxidized dye molecules and possibly poor electron injection efficiency caused the poor performance of the two natural dyes in dye-sensitized solar cells. In addition, for carminic acid electron injection into the conduction band of TiO2 appears to be poor.

In this work a combined chromatographic and spectroscopic approach is used to provide a diagnostic assessment of semi-synthetic ammoniacal cochineal through the syntheses of its dyes and lakes according to art historical recipes. Commercially introduced in the late XIX century as a dye and pigment, it was used to obtain a brilliant purplish/violet nuance which provided a more stable option over carminic acid although its evidenced use in manufacts and artworks of heritage importance have been scarcely documented. Through HPLC-DAD, it has been possible to identify 4-aminocarminic acid as the main component of ammoniacal cochineal highlighting a chemical formula analogous to acid stable carmine, a recent patented food dye. FTIR clearly distinguishes the amine group in the ammoniacal cochineal dye preparation and TLC-SERS allows for an adequate separation and spectral differentiation in its main components to be evidenced. Colloidal SERS has permitted spectral markers useful in discerning ammoniacal cochineal over carminic acid to be highlighted and discussed. Finally, the methods experimented in this study for the identification of ammoniacal cochineal have been validated on analyzing a sample of dyed wool.

A novel chemiluminescence (CL) system is introduced based on the oxidation of carminic acid by KMnO4 in acidic conditions. CdS quantum dots (QDs) were synthesized using a facile hydrothermal method which efficiently enhanced the intensity of the CL system. A possible mechanism for the proposed system is presented using the kinetic curves, CL spectra, photoluminescence (PL), and ultraviolet-visible (UV-Vis) analysis. The emission intensity of the KMnO4-carminic acid-CdS QDs system was quenched in the presence of a trace level of cloxacillin. Based on this quenching effect, a novel and sensitive flow injection CL method was developed for determining cloxacillin concentrations. At optimal experimental conditions, the decreased CL intensity had a good linear relation with the cloxacillin concentration in the range of 0.008 to 22.0 mg L(-1). The detection limit (3σ) was 5.8 µg L(-1). The precision of the method was calculated by analyzing samples containing 4.0 mg L(-1) of cloxacillin (n=11), and the relative standard deviations (RSD%) were 2.08%. The feasibility of the method is also demonstrated for determining cloxacillin concentrations in environmental water samples and a pharmaceutical formulation.

The fundamental chemistry underlying the photo-induced degradation of cochineal (carmine), a red dye extracted from South American scale insects and used as an artist colorant, and its stability in solution and as a lake pigment in different paint media exposed to light in various ambient environments is examined. The influence of oxygen on the photodegradation was examined for dye solutions and for solid paint samples containing the lake pigment, and the effect of ambient humidity was assessed for the paint samples. The degradation was followed using absorbance spectroscopy, and characterized using IR and LC-MS. Results indicate lower reaction rates of the carminic acid chromophore in solution and in oil paints during light exposure in anoxic conditions; whereas watercolor paints demonstrated a stronger dependence of the rates on the ambient humidity. A ring opening of the anthraquinone core is suggested in the breakdown of the dye and pigment. This study illustrates that solution phase systems may serve as simple models to assess the kinetics and mechanism of photochemical breakdown of organic-based pigments in solid samples.

Using the carminic acid assay, we determined the concentration of boron in oilfield waters. We investigated the effect of high concentrations of salts and dissolved metals on the assay performance. The influence of temperature, development time, reagent concentration, and water volume was studied. Ten produced and flowback water samples of different origins were measured, and the method was successfully validated against ICP-MS measurements. In water-stressed regions, produced water is a potential source of fresh water for irrigation, industrial applications, or consumption. Therefore, boron concentration must be determined and controlled to match the envisaged waste water reuse. Fast, precise, and onsite measurements are needed to minimize errors introduced by sample transportation to laboratories. We found that the optimum conditions for our application were a 5:1 mixing volume ratio (reagent to sample), a 1 g L(-1) carminic acid concentration in 99.99% sulfuric acid, and a 30 min reaction time at ambient temperature (20 °C to 23 °C). Absorption values were best measured at 610 nm and 630 nm and baseline corrected at 865 nm. Under these conditions, the sensitivity of the assay to boron was maximized while its cross-sensitivity to dissolved titanium, iron, barium and zirconium was minimized, alleviating the need for masking agents and extraction methods.

In the European Union, carminic acid and its ammonium, calcium, potassium or sodium salts and its aluminium lakes are approved as food additive E120. In beverages obtained from the German market 4-aminocarminic acid (“acid-stable carmine”) was detected by HPLC–PDA and LC–MS/MS. Isolation of the colorant from a liquid dye preparation used for the production of a beverage sample and subsequent NMR analysis confirmed the presence of 4-aminocarminic acid. Synthesis of 15N-4-aminocarminic acid clearly demonstrated that “acid-stable carmine” is not the ammonium salt of carminic acid, which is approved as food additive in the European Union. In fact, nitrogen in “acid-stable carmine” is covalently bound. The molecular structure of carminic acid is chemically modified and 4-aminocarminic acid does not comply with the specifications laid down for E120 in Commission Regulation (EU) No 231/2012. 4-Aminocarminic acid was also detected in the red-colored glaze of a raspberry cake and in the liquid dye preparation used for coloring this glaze.

A photo-active nano-hybrid material consisting of titania nanoparticles, carminic acid, and sulphonic acid functionalized porphyrin is reported here. In an attempt to extend the absorption spectrum of titania to visible region by co-adsorbing carminic acid and sulphonic acid functionalized porphyrin on its surface. Interesting changes in the UV-visible and fluorescence spectra were noticed. The adsorption of carminic acid resulted in the formation of charge transfer complex with titania nanoparticles. This was confirmed by the electronic absorption and fluorescence emission spectroscopies. Chemisorption of porphyrin on the carminic acid functionalized titania further boosted the charge transfer effect. This was noticed by the increase in intensity and width of the charge transfer absorption and emission bands. Energy level diagram showed that the interaction among the constituents of the nano-hybrid assembly permitted the flow of electron in a cascade manner from carminic acid to TiO2.This also allowed direct flow of electrons either from carminic acid or porphyrin toward titania. The material was used as an active blend in hybrid bulk heterojunction solar cells. Co-functionalized TiO2-based devices were found 3.5 times more efficient than the reference device but morphology of the device proved a major setback.

In this study, ZnO and CdS deposited ZnO nanostructured material was successfully synthesized by using co-precipitation and ultra-sonication methods, respectively. A comparative study of the sensitization of ZnO and nanostructured ZnO/CdS with two different dyes (carminic acid and pyrocatechol violet) and applications of the synthesized material in solid state dye sensitized solar cells (DSSCs) are reported here. The characterization of the materials was performed by using x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The SEM and TEM results showed that surface of ZnO nano spheres is well covered with CdS. UV–visible spectrum showed the rise of a new optical band due to CdS deposition which effectively tuned the band gap of ZnO from 3.12 eV to 1.877 eV. XRD analysis revealed the successful formation of hexagonal phases of CdS and ZnO. The materials were applied as photoanodes in DSSCs with and without dye sensitization. P3HT (Poly (3-hexylthiophene) was used as a hole conducting polymer. CdS deposition and sensitization with different dyes showed a significant effect on the overall efficiency of fabricated devices. The ZnO/CdS based DSSC sensitized with carminic acid showed a current density (Jsc) of 8.72 mA/cm2 with an open circuit voltage (Voc) of 0.43 V and an overall efficiency of 1.42%. While the same photoanode material sensitized with pyrocatechol violet gave Jsc value of 9.13 mA/cm2 with a Voc of 0.39 V and an overall efficiency of 1.55%.

Supramolecular fluorescent probe, which was designed and modeled from carminic acid (CA) and γ-cyclodextrins (γ-CDs), was initially qualified and stated comprehensively. Fluorescence intensity of CA could be dramatically enhanced ∼850 a.u. through formation of a supramolecular fluorescent probe CA@γ-CDs. The super-probe was verified by geometric conformation and molecular docking, and subsequently characterized by FT-IR, NMR, XRD and fluorescence lifetime. Furthermore, the CA@γ-CDs probe was proved on the detection of fungicide 2-aminobenzidazole (2-BZ). Finally, fluorescence performance of CA and the application of the probe for molecular recognition were both motivated by γ-CDs significantly, which could facilitate the fluorescence detection of CA more extensively and precisely.

The incorporation of pigments and natural polyphenols into inorganic matrices, resulting in a hybrid material that improves the resistance and chemical stability of the pigments and the antioxidant capacity of the materials, has been of great interest to the pharmaceutical, chemical and food industries. The aim of this work was to prepare and characterize a bifunctional pigment&ndash, antioxidant nanomaterial-based carminic acid-decorated solid core-mesoporous shell silica nanoparticles, evaluating its properties as a pigment, its antioxidant capacity and its properties as a chemical stabilizer of emulsions. The chemical stability of oil-in-water (O/W) Pickering emulsions was evaluated determining the stability of vitamin E solubilized in the oil phase. Carminic acid was attached through the action of coupling ethylcarbodiimide hydrochloride (EDC)/N-hydroxysuccinimide (NHS) agents, and the resulting spherical and homogeneous nanoparticles showed a diameter close to 175 nm. A notorious change of emulsion color was observed by the addition of the nanomaterial. Emulsions showed an attractive pink color, and when the pH was adjusted to pH 3 and pH 9, a change in color was observed, analogous to carminic acid in solution. The nanomaterial incorporation also improved chemical stability, decreasing vitamin E consumption to 9.26% of the initial value, demonstrating an important antioxidant effect of the developed nanomaterial.

Protein misfolding leads to several human pathologies. So far, there has not been much success on the remediations of these protein conformational disorders. Since these diseases arise as a result of protein aggregation, hence inhibition of aggregation could be a promising approach for designing new therapeutics. For which; polyphenols, antibiotics and other small compounds have been tested by the researchers in the recent past, but so far there has not been much success. Here we have investigated the effect of carminic acid over Human serum albumin in an in vitro manner. It was observed that there was severe resistance in the increment of fluorescence intensity in the presence of carminic acid when observed through ANS, ThT and RLS, which was further supported by CD and Congo red assay. Microscopic analysis also confirmed that there was aggregation inhibition in the presence of180μM carminic acid. ROS and SDS-PAGE results also established the same. Furthermore, molecular docking was performed to understand the interacting residues which were found to be Arg, Leu, Glu. It is noteworthy that inhibitory effect was concentration dependent and maximum inhibition was found to be in presence of 180 μM of carminic acid. These results shall be helpful in designing the new therapeutics against amyloidosis.