Natural dyes extraction from cochineal (Dactylopius coccus). New extraction methods

Protective effects of the bioactive peptide from maggots against skin flap ischemia‒reperfusion injury in rats

Ischemia‒reperfusion (I/R) injury is a frequently observed complication after flap surgery, and it affects skin flap survival and patient prognosis. Currently, there are no proven safe and effective treatment options to treat skin flap I/R injury. Herein, the potential efficacies of the bioactive peptide from maggots (BPM), as well as its underlying mechanisms, were explored in a rat model of skin flap I/R injury and LPS- or H2O2-elicited RAW 264.7 cells. We demonstrated that BPM significantly ameliorated the area of flap survival, and histological changes in skin tissue in vivo. Furthermore, BPM could markedly restore or enhance Nrf2 and HO-1 levels, and suppress the expression of pro-inflammatory cytokines, including TLR4, p-IκB, NFκB p65, p-p65, IL-6, and TNF-α in I/R-injured skin flaps. In addition, BPM treatment exhibited excellent biocompatibility with an adequate safety profile, while it exhibited superior ROS-scavenging ability and the upregulation of antioxidant enzymes in vitro. Mechanistically, the above benefits related to BPM involved the activation of Nrf2/HO-1 and suppression of TLR4/NF-κB pathway. Taken together, this study may provide a scientific basis for the potential therapeutic effect of BPM in the prevention of skin flap I/R injury and other related diseases.

Interactions of Opuntia ficus-indica with Dactylopius coccus and D. opuntiae (Hemiptera: Dactylopiidae) through the Study of Their Volatile Compounds

Opuntia ficus-indica has always interacted with many phytophagous insects; two of them are Dactylopius coccus and D. opuntiae. Fine cochineal (D. coccus) is produced to extract carminic acid, and D. opuntiae, or wild cochineal, is an invasive pest of O. ficus-indica in more than 20 countries around the world. Despite the economic and environmental relevance of this cactus, D. opuntiae, and D. coccus, there are few studies that have explored volatile organic compounds (VOCs) derived from the plant-insect interaction. The aim of this work was to determine the VOCs produced by D. coccus and D. opuntiae and to identify different VOCs in cladodes infested by each Dactylopius species. The VOCs (essential oils) were obtained by hydrodistillation and identified by GC-MS. A total of 66 VOCs from both Dactylopius species were identified, and 125 from the Esmeralda and Rojo Pelón cultivars infested by D. coccus and D. opuntiae, respectively, were determined. Differential VOC production due to infestation by each Dactylopius species was also found. Some changes in methyl salicylate, terpenes such as linalool, or the alcohol p-vinylguaiacol were related to Dactylopius feeding on the cladodes of their respective cultivars. Changes in these VOCs and their probable role in plant defense mechanisms should receive more attention because this knowledge could improve D. coccus rearing or its inclusion in breeding programs for D. opuntiae control in regions where it is a key pest of O. ficus-indica.

Gelatin/polychromatic materials microgels enhanced by carnosic acid inclusions and its application in 2D pattern printing and multi-nozzle food 3D printing

Natural polychromatic biomaterials (like carminic acid and gardenia yellow) possess coloring merits and functionality, but are instable under light and heat. Self-assembly of gelatin and polychromatic materials could be induced by carnosic acid inclusions, illustrating great potential in food application. Antioxidant properties, pigment retention rates, UV irradiation stability, rheological properties, and physical resistances (oil, ethanol, heat and microwave) of samples were improved by carnosic acid inclusions, owing to the newly formed hydrogen bonding and electrostatic interactions (UV spectrum, particle size, zeta potential, FTIR, XPS and SEM). The improved properties contributed to the 2D printed pattern stability and the applicability for producing specialized products with high printability and fastness. On the basis of Subtractive Color-Mixing Principle, further three-dimensional dyeing microgel systems were built and modulated; it could functionalize bean paste/carboxymethyl-cellulose food systems, maintain the excellent self-supporting ability & mechanical strength, and promote single/dual-nozzle 3D printing application. Therefore, the self-assembled gelatin/polychromatic materials/carnosic acid microgel samples could not only achieve outstanding 2D printed pattern stability, and could be also promisingly applied in single/dual-nozzle 3D printing for modern innovative, creative food fields.

Extraction pathways and purification strategies towards carminic acid as natural-based food colorant: A comprehensive review

As a current trend of fabricating healthier products, food manufacturing companies seek for natural-based food colorant aiming to replace the synthetic ones, which apart from meeting sensorial and organoleptic aspects, they can also act as health promoters offering additional added value. Carminic acid is a natural based food colorant typically found in several insect taxa. However, there are current approaches which pursue the production of this natural pigment via biotechnological synthesis. To date, this colorant has been intensively applied in the manufacture of several food items. Unfortunately, one of the main limitations deals with the establishment of the right protocol of extraction and purification of this component since there is no report analyzing the main extraction techniques for obtaining carminic acid. Therefore, this review, for the first time, comprehensively analyzes the ongoing strategies and protocols proposed by scientists towards either extraction or purification of carminic acid from its origin source, and from biotechnological systems. Emphasis has been focused on the main findings dealing with extraction techniques and the relevant insights in the field. A detailed discussion is provided on the advantages and drawbacks of the reported extraction and purification methods, main solvents used and their key interactions with target molecules.

Dactylopius opuntiae [Cockerell] Could Be a Source of Antioxidants for the Preservation of Beef Patties

Dactylopius opuntiae is an insect pest that contains at least carminic acid, which has antioxidant properties. Since there is a relationship between the antioxidant ability and preservative action of compounds applied to meat products, the purpose of this study was to evaluate the antioxidant activity and usefulness of a D. opuntiae extract for beef patty preservation. The insects were bred and processed to obtain a liquid extract. For the extract, its carminic acid content, antioxidant activity against two free radicals, and actions on food quality parameters were determined. The D. opuntiae dry powder contained 2.91% w/w carminic acid, while the liquid extract exhibited an IC50 value of 3437.8 ± 67.8 and 19633.0 ± 674.5 µg/mL against the DPPH and ABTS radicals. Nevertheless, these antioxidant actions were lower than those found in a D. coccus extract. The D. opuntiae extract improved in a short time the redness and yellowness, eliminated the unfavorable effect of their vehicle on the MetMb level, and greatly reduced the TBARS formation. For the first time, an extract of D. opuntiae was applied to beef patties, and its beneficial antioxidant action on meat acceptance parameters was confirmed, which has potential commercial applications.

Advancements in Sustainable Natural Dyes for Textile Applications: A Review

The dyeing and finishing step represents a clear hotspot in the textile supply chain as the wet processing stages require significant amounts of water, energy, and chemicals. In order to tackle environmental issues, natural dyes are gaining attention from researchers as more sustainable alternatives to synthetic ones. This review discusses the topic of natural dyes, providing a description of their main features and differences compared to synthetic dyes, and encompasses a summary of recent research in the field of natural dyes with specific reference to the following areas of sustainable innovation: extraction techniques, the preparation of substrates, the mordanting process, and the dyeing process. The literature review showed that promising new technologies and techniques have been successfully employed to improve the performance and sustainability of natural dyeing processes, but several limitations such as the poor fastness properties of natural dyes, their low affinity with textiles substrates, difficulties in the reproducibility of shades, as well as other factors such as cost-effectiveness considerations, still prevent industry from adopting natural dyes on a larger scale and will require further research in order to expand their use beyond niche applications.

A Multidimensional Review of Pimpinella anisum and Recommendation for Future Research to Face Adverse Climatic Conditions

Anise, or Pimpinella anisum, has a long history of usage in traditional and alternative medicine, as well as in the pharmaceutical sector. The species is native to Southwest Asia, the Middle East, and the Mediterranean region. The current studies have revealed that wild and cultivated P. anisum are rich in bioactive compounds, such as phenols, tannins, carotenoids, and fatty acids. Different parts of P. anisum plant are used treatment of diseases, the treatment of pathogens for antiviral, antibacterial, and antifungal purposes, and cosmetics. In this paper, we reviewed the current knowledge on geographical distribution, cultivation, chemical compounds, extraction methods, and agronomic and medicinal uses of Pimpinella anisum. Equally, we suggested guidelines for future research to fill the gap in less investigated issues. Data for this paper was gathered via electronic literature search on Google, Google Scholar, and databases counting, Science Direct, Scopus, Springer, PubMed, and Hindawi, from 1930 to 2022. Analyzed data show that Pimpinella anisum is currently recorded from Portugal on the Atlantic Ocean in the west to China in the East. With new extraction methods, such as Ultrasound-Assisted Extraction, scientists have explored the higher quantities of polyphenols, flavonoids, and antioxidants, and revealed new constituents such as trans-anethole and estragole found in essential oil fruits by gas chromatography-mass spectrometry (GC–MS). These compounds showed significant therapeutic benefits against diseases, pathogens, and cosmetic roles. However, with the current impacts of climate change on natural vegetation cover, more investigations are needed to understand how these affect the geographical distribution, metabolic aspects, and chemical properties of Pimpinella anisum. These are suggested to increase the value of the species and ensure its conservation.

Insight into the Progress on Natural Dyes: Sources, Structural Features, Health Effects, Challenges, and Potential

(1) Background: Dyes play an important role in food, medicine, textile, and other industries, which make human life more colorful. With the increasing demand for food safety, the development of natural dyes becomes more and more attractive. (2) Methods: The literature was searched using the electronic databases PubMed, Web of Science, and SciFinder and this scoping review was carried out following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). (3) Results: 248 articles were included in this review. This review summarizes the research progress on natural dyes in the last ten years. According to structural features, natural dyes mainly include carotenoids, polyphenols, porphyrins, and alkaloids, and some of the newest dyes are summarized. Some pharmacological activities of carotenoids, anthocyanin, curcumin, and betalains in the last 10 years are summarized, and the biological effects of dyes regarding illumination conditions. The disadvantages of natural dyes, including sources, cost, stability, and poor bioavailability, limit their application. Here, some feasible strategies (potential resources, biotechnology, new extraction and separation strategies, strategies for improving stability) are described, which will contribute to the development and utilization of natural dyes. (4) Conclusion: Natural dyes show health benefits and potential in food additives. However, it is necessary for natural dyes to pass toxicity tests and quality tests and receive many regulatory approvals before their final entry into the market as food colorants or as drugs.

Natural Food Colorants and Preservatives: A Review, a Demand, and a Challenge

The looming urgency of feeding the growing world population along with the increasing consumers' awareness and expectations have driven the evolution of food production systems and the processes and products applied in the food industry. Although substantial progress has been made on food additives, the controversy in which some of them are still shrouded has encouraged research on safer and healthier next generations. These additives can come from natural sources and confer numerous benefits for health, beyond serving the purpose of coloring or preserving, among others. As limiting factors, these additives are often related to stability, sustainability, and cost-effectiveness issues, which justify the need for innovative solutions. In this context, and with the advances witnessed in computers and computational methodologies for in silico experimental aid, the development of new safer and more efficient natural additives with dual functionality (colorant and preservative), for instance by the copigmentation phenomena, may be achieved more efficiently, circumventing the current difficulties.

Natural Dyeing of Modified Cotton Fabric with Cochineal Dye

Natural dyes are not harmful to the environment owing to their biodegradability. For dye application to textiles, salts are necessary as mordant or electrolytes and make an environmental impact. In this paper, the influence of cationization during mercerization to the dyeing of cotton fabric with natural dye from Dactylopius coccus was researched. For this purpose, bleached cotton fabric as well as fabric cationized with Rewin OS was pre-mordanted using iron(II) sulfate heptahydrate (FeSO₄·7H₂O) and dyed with natural cochineal dye with and without electrolyte addition. For the characterization of surface changes after cationization, an electrokinetic analysis on SurPASS was performed and compared to pre-mordanting. For determination of dye exhaustion, the analysis of dye solution was performed on a UV/VIS spectrophotometer Cary 50 Solascreen. Spectrophotometric analysis was performed using a Datacolor 850 spectrophotometer, measuring remission "until tolerance" and the whiteness degree, color parameters, color depth (K/S), and colorfastness of dyed fabric were calculated. Levelness was determined by visual assessment. Cationized cotton fabrics showed better absorption and colorfastness. Pre-mordanting and cationization showed synergism. The electrolytes improved the process of dye absorption. However, when natural dyeing was performed on cotton fabric cationized during mercerization, similar chromacity, uniform color, and colorfastness were achieved with and without electrolyte, resulting in pure purple hue of cochineal. For achieving a violet hue, pre-mordanting with Fe-salt was needed. Therefore, salt can be reduced or even unnecessary, which makes this process of natural dyeing more environmentally friendly.

Stressing the differences in alizarin and purpurin dyes through UV-visible light absorption and 1H-NMR spectroscopies

Three anthraquinone-based chromophores (9,10-anthraquinone, alizarin, purpurin) are compared from the point of view of their experimental and computed NMR and UV-visible light absorption spectra. Using an hybrid (explicit/implicit) solvent model,...

Assessment of the lipid oxidation, color and sensorial acceptance of fresh sausage formulated with potassium bixinate as a substitute for sodium nitrite and carmine

This work aimed to evaluate the lipid oxidation, color, and sensory acceptance of sausages formulated with potassium bixinate (BP) as a substitute for carmine (Car) and sodium nitrite (SNi). Six different treatments (CT-control; CA-40 ppm Car; NIT-150 ppm SNi; C/N-40 ppm Car, and 150 ppm SNi; C/N/B-20 ppm Car, 75 ppm SNi, and 250 ppm BP; and BIX-500 ppm BP) were evaluated along 15 days. BP provided significantly lower levels of lipid oxidation to the samples (C/N/B and BIX) when compared to CT and significantly equal to CA, NIT, and C/N after 15 days (both p < 0.05). BP significantly increased the red (a*) and yellow (b*) intensity of sausages (p < 0.05), providing the highest values in both raw and roasted samples. Sausages formulated with BP did not differ in preference in visual analysis (p > 0.05), and both roasted were preferred over CT (p < 0.05). Although sausages formulated with carmine had better visual acceptance, BIX and C/N did not differ significantly (p > 0.05) after five days. BP was identified in taste analysis; however, it was preferred in the ordination analysis (both p < 0.01). Therefore, the replacement of SNi and Car by BP showed to be a viable alternative.

Cochineal carmine adsorbed on layered zinc hydroxide salt applied on mortadella to improve color stability

The pink/reddish color meat products characteristic of cured meat without the curing salts is a meat industry demand to serve consumers who are looking for healthy foods with the usual sensory characteristics. This study aimed to obtain and characterize a hybrid dye and use it as a replacer for curing salt in the production of pink/red color in mortadella stored for 40 days. A layered zinc hydroxide salt (ZHN) was obtained by alkaline precipitation to immobilize and increase cochineal carmine stability, obtaining the hybrid dye (ZHN-carmine) by ion exchange in aqueous solution. The ZHN-carmine was subjected to ultrasound to increase color intensity and reduce the amount of application. ZHN, cochineal carmine and ZHN-carmine were characterized by X-Ray Diffraction, Fourier-Transform Infrared Spectroscopy, Thermogravimetric Analysis and Differential Scanning Calorimetry. The ZHN-carmine was used in the mortadella elaboration traditionally prepared with nitrite/nitrate and/or carmine. In the characterization it was observed that carmine dye was adsorbed on the lamellar compound surface and over the mortadella storage, it ensures a more stable pink/reddish color than the others product formulations. A more intense color with lower L* and higher a* values was observed for mortadella added of ZHN-carmine ultrasound-assisted. Therefore, the lamellar matrix adsorbed with cochineal carmine may a suitable and useful alternative to obtain the pink/reddish color characteristic of cooked meat products by applying a natural hybrid dye.

Hybrid dye was obtained by adsorbing carmine dye on a layered zinc hydroxide salt

The hybrid-dye mortadella had a stable pink/reddish color characteristic

The ultrasound improved the color supplied by hybrid dye in mortadella

Hybrid dye may be used as curing salt replacer on mortadella without color loss

Insects as an Alternative Protein Source

The recent COVID-19 pandemic drastically affected food supply chains worldwide, showing the vulnerability of food security. Efforts to develop alternative protein sources that are sustainable and can help alleviate global food shortage problems should be prioritized. Insects have been part of our diet for thousands of years and still are today, and market trends show a global increase in the number of food-grade insect producers. The global market for edible insects has been forecasted to reach US$8 billion by the year 2030. Insects are highly nutritious and have bioactive peptides with potential therapeutic effects. This review provides an overview of the consumption of insects from ancient to modern times, discusses the rationale for using insects as alternative protein sources, and presents a summary of the major insects consumed worldwide as well as a brief description of the traditional and novel technologies currently used to process insects and/or extract their nutritional components. Expected final online publication date for the Annual Review of Food Science and Technology, Volume 13 is March 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Degradation of synthetic dyes using nanoparticles: a mini-review

The industrial revolution has marked a strong impact on financial upgradation of several countries, and increase in the industrial establishment globally has direct impact on environment because of the release of unwanted product in air and inside the water bodies. The use of dyes has increased tremendously in various industries ranging from food, leather, textile, paper, cosmetic, pharmaceuticals, etc. The problem has emerged due to disposing of the dyes in the open environment, and mostly it is disposed along with the industrial wastes into the water bodies, which becomes harmful for animals, aquatic life and human health. This review highlights the role of the nanoparticles particularly biosynthesized nanoparticles for eliminating the dyes from the industrial wastewater. There are several methods for the synthesis of nanoparticle including physical, chemical and green synthesis of nanoparticles commonly known as biological method. Among all, the biological method is considered as the rapid, easy, eco-friendly and is being performed at mild conditions. The uses of nanoparticles for removal of dyes from water minimize the hazardous impact and thus considered to be the best approach as far as water quality and safety of environment is concerned.

Disposable Electrochemical Sensor for Food Colorants Detection by Reduced Graphene Oxide and Methionine Film Modified Screen Printed Carbon Electrode

A facile synthesis of reduced graphene oxide (rGO) and methionine film modified screen printed carbon electrode (rGO-methionine/SPCE) was proposed as a disposable sensor for determination of food colorants including amaranth, tartrazine, sunset yellow, and carminic acid. The fabrication process can be achieved in only 2 steps including drop-casting of rGO and electropolymerization of poly(L-methionine) film on SPCE. Surface morphology of modified electrode was studied by scanning electron microscopy (SEM). This work showed a successfully developed novel disposable sensor for detection of all 4 dyes as food colorants. The electrochemical behavior of all 4 food colorants were investigated on modified electrodes. The rGO-methionine/SPCE significantly enhanced catalytic activity of all 4 dyes. The pH value and accumulation time were optimized to obtain optimal condition of each colorant. Differential pulse voltammetry (DPV) was used for determination, and two linear detection ranges were observed for each dye. Linear detection ranges were found from 1 to 10 and 10 to 100 µM for amaranth, 1 to 10 and 10 to 85 µM for tartrazine, 1 to 10 and 10 to 50 µM for sunset yellow, and 1 to 20 and 20 to 60 µM for carminic acid. The limit of detection (LOD) was calculated at 57, 41, 48, and 36 nM for amaranth, tartrazine, sunset yellow, and carminic acid, respectively. In addition, the modified sensor also demonstrated high tolerance to interference substances, good repeatability, and high performance for real sample analysis.

Patch Testing With Carmine 2.5% in Petrolatum by the North American Contact Dermatitis Group, 2011-2012

BACKGROUND

Carmine is a natural red dye that may cause allergic contact dermatitis.

OBJECTIVE

The aim of this study was to analyze patch test reactions to carmine (2.5% in petrolatum) and characterize carmine-positive patients.

METHODS

This study conducted a retrospective analysis of North American Contact Dermatitis Group data compiled between 2011 and 2012.

RESULTS

Of 4240 patients patch tested to carmine, 132 (3.1%) had reactions with a final interpretation of "allergic" (positive). Carmine-positive patients were significantly more likely to be female (77.7% vs 68.3%; P = 0.0237) and have a final primary diagnosis of allergic contact dermatitis (74.8% vs 47.2%; P < 0.0001). As compared with carmine-negative patients, carmine-positive patients were significantly more likely to have involvement of all facial sites combined (48.1% vs 29.9%; P < 0.0001) and the lips (7.6% vs 3.6%; P = 0.0166). At final reading, most carmine reactions were weak (+; 64.9%). Approximately half (53.4%) were currently clinically relevant; identified sources were primarily personal care products (77.1%), especially makeup (31.4%) and lip products (8.6%).

CONCLUSIONS

Weak patch test reactions to carmine should be interpreted with caution. Allergic contact dermatitis to carmine should be suspected in women with facial and/or lip dermatitis, especially those using carmine-containing cosmetics.

Effects of different food ingredients on the color and absorption spectrum of carminic acid and carminic aluminum lake

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.

Cochineal quinone carbon dot synthesis via a keto–enol tautomerism strategy and their intermolecular photo-induced cross-redox interactions with tetracycline

Specific molecular recognition of tetracycline by carminic acid-formed carbon dots taking advantage of the common quinone molecular structural unit.

Green Dyeing and Antibacterial Treatment of Hemp Fabrics Using Punica granatum Peel Extracts

In this study, the dyeing performance and antibacterial properties of pomegranate (Punica granatum) peel extracts were investigated, when applied to hemp fabric. A tannin-rich natural dye was extracted using water at 100°C. As the antibacterial agent was sensitive to temperature, it was extracted using Soxhlet apparatus with methanol at 55°C. The color strength (K/S) values were investigated and found to increase in line with the dye concentration, dyeing time, and temperature. Optimal dyeing of the hemp fabric was achieved when applying 6% w/v of extract at 80°C for 60 min. This produced a yellowish-brown appearance. The dyed fabrics were rated as good to excellent for color fastness against washing, water, sea water, and perspiration. The dyed fabrics were next finished with the antibacterial agent extracted from the peel and tested for activity against Staphylococcus aureus (Gram positive) and Klebsiella pneumoniae (Gram negative), using the AATCC-100 (percentage reduction) test. The fabric was demonstrated to be 99.99% effective against Staphylococcus aureus, and this was conserved across 20 wash cycles.

Designing and preparing supramolecular fluorescent probe based on carminic acid and γ-cyclodextrins and studying their application for detection of 2-aminobenzidazole

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.

Application of Natural Pigments in Ordinary Cooked Ham

The possibility of obtaining a carmine or pink color on ordinary cooked ham by applying natural dyes from three plant species, namely red radish (Raphanus sativus L.), hibiscus (Roselle sabdariffa L.) and red beetroot (Beta vulgaris L.), was investigated. The extracts were evaluated for the stability at physical-chemical parameters and subjected to cytotoxicity assays in the gastric cell line AGS Encapsulation of the extracts in soybean lecithin liposomes and maltodextrin microcapsules was performed. Lyophilized extracts before and after encapsulation in maltodextrin were applied in the formulation of ordinary cooked ham and used in a pilot scale of production. The color of cooked ham samples from different assays was evaluated visually and by colorimetry. The results suggest that the coloration of ordinary cooked ham obtained with extracts of red beetroot is very promising for future applications in this type of meat product.

Vibrational and electronic spectroscopic detection and quantification of carminic acid in candies

Carminic acid (CA) contained in one kind of gummy candy was detected and quantified by using vibrational and electronic spectroscopy, respectively; the proposed methodology in solution is simple and rapid without sample pretreatment as usually used and reported. The identification of CA in candies was performed through the Raman and surface enhanced Raman scattering (SERS) spectra along with the equivalent spectral data from the natural CA dye. A modified silver colloidal solution was used in order to obtain SERS activity of CA at very low concentration in colloidal aqueous solution. Theoretical calculations allow infer about both the CA/silver surface interaction nature and on the orientation of CA on the surface. The electronic spectroscopic (UV-Vis) data allowed quantify CA in candies; the amount resulted nearly identical to that determined from HPLC traditional measurements. The present results should contribute to the health of children consumers.

Carminic Acid Stabilized with Aluminum-Magnesium Hydroxycarbonate as New Colorant Reducing Flammability of Polymer Composites

In this study, hybrid pigments based on carminic acid (CA) were synthesized and applied in polymer materials. Modification of aluminum-magnesium hydroxycarbonate (LH) with CA transformed the soluble chromophore into an organic-inorganic hybrid colorant. Secondary ion mass spectroscopy (TOF-SIMS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and UV-Vis spectroscopy were used to study the structure, composition, and morphology of the insoluble LH/CA colorant. Successful modification of the LH was confirmed by the presence of interactions between the LH matrix and molecules of CA. XPS analysis corroborated the presence of CA complexes with Mg2+ ions in the LH host. The batochromic shift in UV-Vis spectra of the organic-inorganic hybrid colorant was attributed to metal-dye interactions in the organic-inorganic hybrid colorants. Strong metal-dye interactions may also be responsible for the improved solvent resistance and chromostability of the modified LH. In comparison to uncolored ethylene-norbornene copolymer (EN), a modified EN sample containing LH/CA pigment showed lower heat release rate (HRR) and reduced total heat release (THR), providing the material with enhanced flame retardancy.

Nanoencapsulation improved water solubility and color stability of carotenoids extracted from Cantaloupe melon (Cucumis melo L.)

Cantaloupe melon carotenoids were encapsulated in porcine gelatin, whey protein isolate and concentrate by emulsification O/W to evaluate which agent could promote an increase in water solubility, and color stability in yogurt. The average particle size obtained was 59.3 (2.60) nm-161.0 (27.30) nm. Encapsulated crude extract in porcine gelatin presented the smallest size and polydispersity index [0.4 (0.04)], and showed sphericity, smooth surface and low agglomeration in SEM. These results associated to the good chemical interaction between the raw materials shown by FTIR, justify the increase in water solubility [0.072 (0.007) mg.mL^-1] compared to the crude extract [0.026 (0.003) mg.mL^-1]. The yogurt added with this nanoencapsulate remained stable for 60 days, unlike the crude extract. The results show that the nanoencapsulation using gelatin increased water solubility and the potential of application of melon carotenoids in food as natural dyes.

Supercritical carbon dioxide as a green media in textile dyeing: A review

This review highlights the great role of supercritical carbon dioxide fluid technology in textile dyeing processes. The unequivocal physical characteristics of supercritical carbon dioxide are presented and further researched to continue the development of high efficiency, compact dyeing to save energy and water in manufacturing processes. This review also focuses on the solubility of the dyes in scCO2 as well as the application of the technology to both synthetic and natural fabrics. Some factors relating to the economics of sustainable scCO2 technology are also outlined.

Improvement of Cochineal Extract (Dactylopius coccus Costa) Properties Based on the Green Synthesis of Silver Nanoparticles for Application in Organic Devices

The UV-Vis absorption and conductivity properties of the organic sample cochineal (Dactylopius coccus Costa) were modified by using it as a reducing agent in the biosynthesis of silver nanoparticles. This was done in a straightforward way in order to allow its possible application in organic devices. The biosynthesized solution exhibited a hybrid material with a UV-Vis absorbance range from 205 to 650 nm. The sizes of silver nanoparticles of the hybrid material were between 5 and 10 nm. X-ray diffraction (XRD) revealed silver structures, when samples were dried at 100°C. At 40°C, the structures detected were chlorargyrite (AgCl) and silver oxide (Ag2O). The nucleation and subsequent growth of the hybrid thin film on the substrates indicated an increase of clusters and roughness in comparison to thin films made solely from cochineal. The thin films of hybrid materials showed an improvement of 40% in their electrical potential. The stability at room temperature demonstrated that the hybrid material could be useful as a potential candidate for photoactive thin films in organic devices.

Assessment of the Dyeing Properties of the Pigments Produced by Talaromyces spp

The high production yields of pigments by Talaromyces spp. and their high thermal stability have implied that industrial application interests may emerge in the food and textile industries, as they both involve subjecting the colourants to high temperatures. The present study aimed to assess the potential application of the pigments produced by Talaromyces spp. in the textile area by studying their dyeing properties. Dyeing studies were performed on wool. The dyeing process consisted of three stages: scouring, mordanting, and dyeing. Two different mordants (alum, A; ferric chloride, F) were tested at different concentrations on fabric weight (A: 5, 10, 15%; F: 10, 20, 30%). The mordanting process had a significant effect on the final colour of the dyed fabrics obtained. The values of dyeing rate constant (k), half-time of dyeing (t_1/2), and sorption kinetics behaviour were evaluated and discussed. The obtained results showed that pigments produced by Talaromyces spp. could serve as a source for the natural dyeing of wool textiles.

Perstraction of Intracellular Pigments through Submerged Fermentation of Talaromyces spp. in a Surfactant Rich Media: A Novel Approach for Enhanced Pigment Recovery

A high percentage of the pigments produced by Talaromyces spp. remains inside the cell, which could lead to a high product concentration inhibition. To overcome this issue an extractive fermentation process, perstraction, was suggested, which involves the extraction of the intracellular products out of the cell by using a two-phase system during the fermentation. The present work studied the effect of various surfactants on secretion of intracellular pigments produced by Talaromyces spp. in submerged fermentation. Surfactants used were: non-ionic surfactants (Tween 80, Span 20 and Triton X-100) and a polyethylene glycerol polymer 8000, at different concentrations (5, 20, 35 g/L). The highest extracellular pigment yield (16 OD500nm) was reached using Triton X-100 (35 g/L), which was 44% higher than the control (no surfactant added). The effect of addition time of the selected surfactant was further studied. The highest extracellular pigment concentration (22 OD500nm) was achieved when the surfactant was added at 120 h of fermentation. Kinetics of extracellular and intracellular pigments were examined. Total pigment at the end of the fermentation using Triton X-100 was 27.7% higher than the control, confirming that the use of surfactants partially alleviated the product inhibition during the pigment production culture.

Biosynthesis and characterization of silver nanoparticles prepared from two novel natural precursors by facile thermal decomposition methods

In this work, two natural sources, including pomegranate peel extract and cochineal dye were employed for the synthesis of silver nanoparticles. The natural silver complex from pomegranate peel extract resulted in nano-sized structures through solution-phase method, but this method was not efficient for cochineal dye-silver precursor and the as-formed products were highly agglomerated. Therefore, an alternative facile solid-state approach was investigated as for both natural precursors and the results showed successful production of well-dispersed nanoparticles with narrow size distribution for cochineal dye-silver precursor. The products were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy dispersive X-ray microanalysis (EDX), and Transmission Electron Microscopy (TEM).

Effect of solvent type and ratio on betacyanins and antioxidant activity of extracts from Hylocereus polyrhizus flesh and peel by supercritical fluid extraction and solvent extraction

The main objective of the present study was to investigate the effect of solvent type and ratio as well as the extraction techniques (i.e. supercritical fluid extraction (SFE) and conventional solvent extraction) on betacyanins and antioxidant activity of the peel and fresh extract from the red pitaya (Hylocereus polyrhizus). The peel and flesh extracts obtained by SFE at 25MPa pressure and 10% EtOH/water (v/v) mixture as a co-solvent contained 24.58 and 91.27mg/100ml total betacyanin, respectively; while the most desirable solvent extraction process resulted in a relatively higher total betacyanin in the peel and flesh extracts (28.44 and 120.28mg/100ml, respectively). The major betacyanins identified in the pitaya peel and flesh extracts were betanin, isobetanin, phyllocactin, butyrylbetanin, isophyllocactin and iso-butyrylbetanin. The flesh extract had the stronger antioxidant activity than the peel extract when the higher proportion of ethanol to water (E/W) was applied for the extraction.

Production of a natural red pigment derived from Opuntia spp. using a novel high pressure CO2 assisted-process

The betalain extraction yield obtained with a novel high pressure CO₂ assited-process was increased 2-fold compared to water extraction.

Adsorption of C.I. Natural Red 4 onto Spongin Skeleton of Marine Demosponge

C.I. Natural Red 4 dye, also known as carmine or cochineal, was adsorbed onto the surface of spongin-based fibrous skeleton of Hippospongia communis marine demosponge for the first time. The influence of the initial concentration of dye, the contact time, and the pH of the solution on the adsorption process was investigated. The results presented here confirm the effectiveness of the proposed method for developing a novel dye/biopolymer hybrid material. The kinetics of the adsorption of carmine onto a marine sponge were also determined. The experimental data correspond directly to a pseudo-second-order model for adsorption kinetics (r² = 0.979–0.999). The hybrid product was subjected to various types of analysis (FT-IR, Raman, ¹³C CP/MAS NMR, XPS) to investigate the nature of the interactions between the spongin (adsorbent) and the dye (the adsorbate). The dominant interactions between the dye and spongin were found to be hydrogen bonds and electrostatic effects. Combining the dye with a spongin support resulted with a novel hybrid material that is potentially attractive for bioactive applications and drug delivery systems.

Light harvesting over a wide range of wavelength using natural dyes of gardenia and cochineal for dye-sensitized solar cells

Two natural dyes extracted from gardenia yellow (Gardenia jasminoides) and cochineal (Dactylopius coccus) were used as sensitizers in the assembly of dye-sensitized solar cells (DSSCs) to harvest light over a wide range of wavelengths. The adsorption characteristics, electrochemical properties and photovoltaic efficiencies of the natural DSSCs were investigated. The adsorption kinetics data of the dyes were obtained in a small adsorption chamber and fitted with a pseudo-second-order model. The photovoltaic performance of a photo-electrode adsorbed with single-dye (gardenia or cochineal) or the mixture or successive adsorption of the two dyes, was evaluated from current-voltage measurements. The energy conversion efficiency of the TiO2 electrode with the successive adsorption of cochineal and gardenia dyes was 0.48%, which was enhanced compared to single-dye adsorption. Overall, a double layer of the two natural dyes as sensitizers was successfully formulated on the nanoporous TiO2 surface based on the differences in their adsorption affinities of gardenia and cochineal.

Isolation of natural red colorants from fermented broth using ionic liquid-based aqueous two-phase systems

There is a growing demand for natural colorants. This is prompting the search for new alternative and "benign" separation systems allowing higher recoveries, extraction yields, and selectivities. This work investigates the use of aqueous two-phase systems (ATPS) based on ionic liquids as extraction processes for the recovery of red colorants from the fermented broth of Penicillium purpurogenum DPUA 1275. Several ATPS based on quaternary ammonium and imidazolium were studied in this work aiming at separating the red colorants produced from the remaining colorants and contaminant proteins present in the fermented broth. The results suggest that the red colorants can be isolated by an appropriate manipulation of some of the process conditions, such as the use of quaternary ammonium with short alkyl chains, alkaline media, and short tie-line lengths (extraction point systems with lower concentrations of ionic liquid). These conditions allow large partition coefficients for the red colorants (K red = 24.4 ± 2.3), high protein removal (60.7 ± 2.8 %) and selectivity parameters (S red/prot = 10.05).