Indigo Carmine Research Articles

Synergistic impact of nano-supramolecular coordination polymer based on cadmium, ethyl nicotinate and thiocyanate ligands as efficient catalyst to remove harmful elements from wastewater.

Under ultrasonication, cadmium nitrate tetrahydrates, ethyl nicotinate (EN), and potassium thiocyanate as connecting ligand self-assembled to form the nanosized supramolecular coordination polymer (NSCP1) and the crystalline supramolecular coordination polymer (SCP1) [Cd(EN)2(SCN)2]. Single crystal SCP1 X-ray diffraction (XRD) revealed that CdII has an octahedral shape. The network structure of SCP1 is composed of chair conformation cyclic [Cd2(SCN)2] n building blocks that form a one dimensional (1D) chain with bilaterally coordinated EN. The 1D-chain is joined to the other by extensive hydrogen bonds, which arrange the chains into a three-dimensional network. By stacking π-π, the strands are fluttering the three-dimensional (3D) network even more. Several structural characterization methods and spectral analyses were used to analyze SCP1 and NSCP1. The heterogeneous catalysts SCP1 and NSCP1 have been shown to display exceptionally strong catalytic activity against the breakdown of the designated contaminant, indigo carmine (IC) color in very short durations under ultraviolet (UV) or ultrasonic wave conditions. The photoluminescence probing approach was utilized to determine the reactive oxygen species and reaction process using the disodium salt of terephthalic acid.

Density Functional Theory analysis and molecular dynamic simulation to understand the mechanism of hazardous dyes adsorption onto cellulose in aqueous solution

This work examines the use of cellulose in the elimination of anionic dye, indigo carmine and methyl red, from aqueous media. Theoretical analyses revealed that the examined compounds had several reactive sites that encouraged dyes to adhere to the cellulose surface, and molecular dynamics simulations demonstrated that this adsorption occurred flat-lying on the cellulose (200) surface. However, it has been discovered that the reactivity of individual molecules is limited in its ability to foretell the effectiveness and characteristics of compound adsorption on cellulose. The capacity to model dye adsorption on polymeric surfaces in the presence of a simulated aqueous solution is one of the key benefits of molecular dynamics modeling, and it can reveal valuable information regarding the selected molecules' adsorption configuration and its competitiveness. Both dyes exhibit high adsorption on the cellulose adsorbent, indicating that chemical bonds play a major role in the adsorption capacity of the dyes. The order of adsorption energy indicates a clear selective adsorption tendency. The radial distribution function analysis shows that both dyes are chemisorbed at the cellulose surface. Quantum and dynamic descriptors have validated the experimental results in the literature. This offers valuable insights into the adsorption mechanism of anionic dyes on cellulose.

Hydrothermal extraction of microcrystalline cellulose from post-consumer indigo denim fabrics and evaluation of its UV blocking property

Abstract Waste cotton clothes, including post-consumer denim fabrics, are abundant biopolymer sources due to their high cellulose content. These waste materials commonly end up in landfills, posing health and environmental concerns and losing valuable cellulosic materials. To address these, this study aims to extract and characterize microcrystalline cellulose (MCC) from post-consumer indigo denim fabrics using a one-step hydrothermal method and evaluate its UV-blocking properties. FTIR and TGA analysis of raw and bleached denim confirmed the presence and purity of cotton cellulose and the indigo dye. Extracted MCC yielded 70-84%, with a degree of polymerization (DP) of 281-299. XRD analysis of the MCC showed a cellulose Type I structure. FTIR suggests the removal of amorphous phases of cellulose, leaving the crystalline structure. SEM meanwhile revealed rod-shaped and rough-surfaced MCC particles with diameters of 10-20 μm and lengths of 45-60 μm. Both FTIR and SEM indicated the retention of indigo dye on MCC surface. Increased acid hydrolysis time led to smaller particle sizes and higher degree of crystallinity (CrI). Indigo PVA-MCC films showed good transparency and effective UV blocking. These results indicate the successful conversion of denim to MCC via the hydrothermal method and the stability of indigo dye in the cellulose matrix.

Micro-nano bubbles in action: AC/TiO2 hybrid photocatalysts for efficient organic pollutant degradation and antibacterial activity

Developing highly active and sustainable photocatalysts is crucial for environmental remediation. This work focuses on the enhanced photocatalytic degradation efficiency of synthetic dyes using TiO2-coated AC hybrid photocatalysts under MNB aeration. The TiO2-coated AC hybrid photocatalyst (HP) was synthesized via a sol-gel method and characterized using XRD, FTIR, SEM, EDS, HR-TEM, and DRS. The study investigated the photocatalytic degradation of three dyes indigo carmine (IC), reactive black 5 (RB5), and methylene blue (MB) in wastewater, with initial dye concentrations ranging from 10 to 100 μM. Under UVA irradiation, the hybrid photocatalyst with MNB aeration (HP + UVA + MNB) achieved the highest degradation efficiencies of 69.09%, 60.06%, and 55.19% for IC, MB, and RB5, respectively. Further analysis showed that the chromophores and complex structures of these dyes were broken into intermediate products. The Langmuir-Hinshelwood kinetic model was used to describe the reaction mechanisms. The HP + UVA + MNB system demonstrated superior photocatalytic degradation activity, making it suitable for operational and environmental applications in dye wastewater treatment. Additionally, the antibacterial properties of AC and HP were tested at 100 μg/mL, showing effectiveness against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli.

From plant to nanomaterial: Green extraction of nanomucilage from Cordia dichotoma fruit and its multi-faceted biological and photocatalytic attributes

This study aimed to evaluate the extraction efficiency of mucilage from Cordia dichotoma fruits using various aqueous extraction methods, including microwave-assisted water extraction (MWE), hot-water extraction (HWE), and cold-water extraction (CWE). Different analytical techniques were employed to characterize the Cordia dichotoma mucilage (CDM). Additionally, the functional properties, anti-microbial, anti-inflammatory, and dye reduction potential of CDM were assessed. The results indicated a significantly (p < 0.05) higher yield of CDM (13.44 ± 0.94 %) using MWE compared to HWE (12.08 ± 0.82 %) and CWE (7.59 ± 0.73 %). The optimal extraction condition was utilized for the spray-drying process, yielding a spray-dried mucilage powder (SDMP) with a yield of 9.52 ± 1.27 %. The presence of galactose and arabinose as major sugar and functional groups such as OH, COOH, CH, and NH from proteins, uronic acids, and sugars were identified. CDM predominantly comprises galactose and arabinose as major sugars. CDM particles exhibited an irregular morphology and demonstrated thermal stability, with maximum weight loss occurring between 221.83 and 478.66 °C. The particle size of CDM was 681.16 ± 2.18 nm with a zeta potential of −21.46 ± 1.72 mV. Rheological analysis revealed that CDM exhibits shear-thinning behavior. Furthermore, CDM displayed inherent biological activities, including antimicrobial and anti-inflammatory properties. The dye reduction potential of CDM was evidenced by an 88.67 % degradation of indigo carmine dye. In summary, this study provides insights into the cost-effective extraction methods for CDM and its potential utilization as an eco-friendly material for dye reduction.

Sustainably feeding the planet through integrated management of blue and green food systems

Sustainably feeding the planet through integrated management of blue and green food systems

Blue food proteins: Novel extraction technologies, properties, bioactivities and applications in foods

Blue food proteins: Novel extraction technologies, properties, bioactivities and applications in foods

Development of Z-scheme BiVO4/g-C3N4/rGO heterojunction nanocomposite for enhanced photocatalytic degradation and antibacterial activity

In this study, we synthesized a novel BiVO4/g-C3N4/rGO (BGR) heterojunction photocatalyst using the hydrothermal method. The synthesized catalysts were characterized through X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDX), Transmission Electron Microscopy (TEM), and Ultraviolet-Visible Diffuse Reflectance Spectroscopy (UV-DRS) to analyze their structural, morphological, and optical properties. The hybrid BGR nanocomposite displayed remarkable absorption characteristics, photocatalytic activity, and notable stability. Photocatalytic degradation performance was evaluated against methylene blue (MB) and indigo carmine (IC) dyes. The BGR ternary hybrid nanocomposites demonstrated significant photocatalytic degradation efficiency, achieving removal rates of 95.6 % for MB and 97.5 % for IC dyes within 120 min. The improved photocatalytic efficiency of the ternary photocatalyst is attributed to superior electron-hole pair separation and the formation of the heterojunction structure. The BGR nanocomposite exhibited excellent recyclability, maintaining its activity and crystalline characteristics over five photodegradation cycles. Additionally, the antibacterial activity of the BGR nanocomposites against Staphylococcus aureus,Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa was evaluated under UV–visible light exposure. This study provides insights for designing efficient visible-light-driven photocatalysts for environmental remediation purposes.

Facile synthesis of zeolitic‐imidazole framework‐67 (ZIF‐67) for the adsorption of indigo carmine dye

AbstractThis study aims to synthesize ZIF‐67 for the adsorption of indigo carmine (I.C.) dye. ZIF‐67 materials were synthesized under different conditions and the synthesis condition of ZIF‐67 giving the best adsorption efficiency was obtained. In batch adsorption studies, pH, adsorbent amount, contact time, initial dye concentration, and temperature effects were investigated. Adsorption data were applied to Langmuir, Freundlich, and Temkin isotherm models. The best correlation value was obtained in Langmuir isotherm (R2 = 0.999). The adsorption of I.C. dye with ZIF‐67 occurred in a monolayer with a homogeneous surface according to Langmuir isotherm. The highest adsorption capacity value of ZIF‐67 metal–organic framework for I.C. dye was found as 370 mg/g. Kinetic model studies were also performed and pseudo first‐order, pseudo second‐order, and intraparticle diffusion models were used. Pseudo second‐order was the best fitting kinetic model to the data (R2 = 0.997). Adsorption mechanisms of ZIF‐67 for I.C. dye include electrostatic interaction, π–π interaction, and hydrogen bonding. Thermodynamic studies showed that I.C. removal by ZIF‐67 is an exothermic and spontaneous process. ZIF‐67 was characterized by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FT‐IR), field emission scanning electron microscope (FE‐SEM), and N2 adsorption–desorption. The surface area of synthesized ZIF‐67 was found 1493 m2 g−1. The salt concentration effect on I.C. adsorption by ZIF‐67 was also investigated, showing an increase in adsorption capacities with increasing salt concentration. The regeneration study was carried out and after 5 cycles, the reduction in efficiency was 21%.

Experimental and theoretical exploration of bactericidal and photo-catalytical activities of hierarchically porous AuNRs@CuO nanocomposite

In this study, a novel binary nanocomposite consisting of CuO nanosheets functionalized with gold nanorods (AuNRs@CuO), was successfully prepared using a two-step synthetic procedure and further investigated via Density Functional Theory. The physicochemical properties of prepared nanomaterials were analysed using Fourier transform infrared spectroscopy, X-ray diffraction, Field emission scanning electron microscopy, High-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy confirming successful fabrication with improved surface properties. Experimental analyses, including antibacterial assays and morphological studies of bacterial cells demonstrates superior bactericidal properties of AuNRs@CuO nanocomposite compared to pristine CuO nanosheets. Furthermore, molecular docking score provide theoretical insights into the underlying mechanism governing the enhanced antibacterial activity, highlighting the favorable interaction with the bacterial cells. The synergistic effect of CuO nanosheets and AuNRs further improves the photocatalytic efficacy, culminating in a high-yield photocatalyst that achieves 98.7% degradation for Indigo carmine under Xenon lamp irradiation compared to 40.8% and 62.4% for AuNRs and CuO nanosheets alone. Improved charge separation and generation of H+ as major reactive oxygen species from the nanocomposite to Indigo carmine was revealed by radical scavenger activity and photoluminescence studies. After cycles of operation, the morphology and surface state of the photocatalyst remained unchanged, as investigated by FESEM and HRTEM analysis. The novelty of this study lies in the integration of AuNRs and CuO nanosheets as an efficient photocatalytic material for the remediation of toxic organic dyes in wastewater, presenting a promising advancement in sustainable water treatment technologies.

Relationship between Indigo, Microorganisms, and Fibers in the Fermentation Liquid at a Natural Indigo Dyeing and Weaving Workshop

Relationship between Indigo, Microorganisms, and Fibers in the Fermentation Liquid at a Natural Indigo Dyeing and Weaving Workshop

New Method of Color Anodic Oxide Coating Using Traditional Indigo Dye

New Method of Color Anodic Oxide Coating Using Traditional Indigo Dye

Streptomyces as a Novel Biotool for Azo Pigments Remediation in Contaminated Scenarios.

Azo pigments are widely used in the textile and leather industry, and they generate diverse contaminants (mainly in wastewater effluents) that affect biological systems, the rhizosphere community, and the natural activities of certain species. This review was performed according to the Systematic Reviews and Meta Analyses (PRISMA) methodology. In the last decade, the use of Streptomyces species as biological azo-degraders has increased, and these bacteria are mainly isolated from mangroves, dye-contaminated soil, and marine sediments. Azo pigments such as acid orange, indigo carmine, Congo red, and Evans blue are the most studied compounds for degradation, and Streptomyces produces extracellular enzymes such as peroxidase, laccase, and azo reductase. These enzymes cleave the molecule through asymmetric cleavage, followed by oxidative cleavage, desulfonation, deamination, and demethylation. Typically, some lignin-derived and phenolic compounds are used as mediators to improve enzyme activity. The degradation process generates diverse compounds, the majority of which are toxic to human cells and, in some cases, can improve the germination process in some horticulture plants. Future research should include analytical methods to detect all of the molecules that are generated in degradation processes to determine the involved reactions. Moreover, future studies should delve into consortium studies to improve degradation efficiency and observe the relationship between microorganisms to generate scale-up biotechnological applications in the wastewater treatment industry.

Blue in Food and Beverages—A Review of Socio-Cultural, Economic, and Environmental Implications

The presented review concerns the cross-disciplinary approaches to the subject of blue food and blue colourants, the socio-cultural aspects of blue food and beverage consumption, human health effects, environmental impact, and economic aspects. Blue colour in relation to food is not only about improving visual appeal, to which the addition of food colouring is usually limited when the food is coloured in some way that does not encourage eating. It is also the rich and complex sociological side related to food, that is, not only the food itself but also the background, dishware, and light, depending on whether we want to encourage—to increase consumption—or discourage—to, for example, reduce the amount of food eaten for dietary purposes. The negative side of consuming and disposing of synthetic dyes and the health-promoting aspects of natural dyes are also mentioned, with the economic and environmental aspects of sourcing natural dyes being discussed. The food industry uses blue dyes not only for consumption, but also for food quality control, taking advantage of the pH-dependent colour change properties of the compound.

Biochar obtained from recovered cellulose and its mixture with conventional sources: Assessment of its potential for the removal of pollutants in water

Yearly thousands of tons of cellulose, in the form of toilet paper, end up in the wastewater treatment plants (WWTP) through the sewage. Cellulose was recovered with a 0.35 mm sieve and processed obtaining three different pellets: pure cellulose, straw mix (50 % cellulose-50 % straw) and wood mix (50 % cellulose-50 % wood). Those materials were carbonized at 750 °C for 210 min producing non-activated biochar. Then, a part of those biochars was biologically activated by fermentation adding minerals, nutrients and a mixture of bacteria. All biochar versions were characterized, assessing the surface, porosity and adsorption capacity for a dye (indigo carmine) and a selection of 5 micropollutants (MPs): benzotriazole, carbamazepine, clarithromycin, DEET, and diclofenac. However, results showed that conventional analysis for adsorbents was not adequate for biologically activated materials since biofilm can obstruct the pores of the supporting material hindering the pollutants' adsorption. Therefore, the biological degradation of the pollutants by the microorganisms was also tested. Finally, biologically activated WOW-Biochar straw mix was the selected material to be further applied in constructed wetlands (CW) due to its higher average MPs removal capacity. Validation test at mesocosm scale demonstrates the suitability of the material as an admixture in CW, reaching a MPs removal rate higher than the 90 % regarding the WWTP inlet.

Blue Food Consumption and Its Relation to Nutrient Intake among Koreans.

(1) Background: "Blue food" is a recently coined term referring to seafood, emphasizing health benefits and sustainability. This study compares nutrient intake levels between Koreans who consume fish and shellfish and those who do not. (2) Methods: Data from the eighth Korea National Health and Nutrition Examination Survey (2019-2020) were used. A total of 9442 individuals were analyzed (≥1 year old). A complex sample design was applied. (3) Results: Younger individuals aged 9 to 29 consumed less fish and shellfish, while those with higher education and income levels consumed more. Compared with the non-consumption group, individuals in the fish and shellfish consumption group exhibited a higher nutrient density in their diets, excluding total fat, saturated fatty acids, monounsaturated fatty acids, and riboflavin (p < 0.01). They also had a higher proportion of nutrient intakes relative to the Recommended Nutrient Intake level for all nutrients than the non-consumption group (p < 0.001), particularly in eicosapentaenoic acid and docosahexaenoic acid intakes. Conversely, the non-consumption group had a higher proportion of nutrient intakes below the Estimated Average Requirement compared with the consumption group. (p < 0.001). (4) Conclusions: Individuals consuming blue food exhibited higher levels of nutrient intake. Developing strategies to promote the consumption of blue food, considering factors such as age, education, and income, is essential.

The effect of silica-doped graphene oxide (GO-SiO2) on persulfate activation for the removal of Acid Blue 25.

The release of synthetic dyes into water bodies poses many environmental issues, and their removal is a necessity. Advanced oxidation processes (AOPs) can be employed for removal, in many of which a catalyst is used. graphene oxide (GO) is a viable catalyst due to its distinctive structural properties; however, it is reportedly incapable of effectively activating persulfate. Thus, this study delves for the first time into the influence of doping silica on enhancing GO's catalytic performance to activate persulfate for decolorizing Acid Blue 25 (AB25). Based on the results, an equal weight proportion of GO to silica was selected as the most efficient ratio. In addition, pH had no significant effect on removal efficiency, while temperature had the highest impact. Within 150 min with 0.075 gr/L of GO-SiO2 as the catalyst and 1 gr/L of Na2S2O8 as the oxidant, the investigated process removed Acid Blue 25 up to 82%, which was 9% higher than when GO alone was used as the catalyst. As for COD removal, the contribution of doping silica was more significant and led to 37% COD removal, which was 17% higher than when GO alone was used.

Spectrophotometric determination for green hydrophobic deep eutectic solvent-based microextraction of Brilliant Blue FCF (E133) from beverages

In this study, a simple, sensitive, and rapid method called green hydrophobic deep eutectic solvent-based liquid-liquid microextraction was developed to extract Brilliant Blue FCF dye from beverages. This method utilizes hydrophobic DES obtained by forming tetrabutylammonium bromide and 1-octanol in a 1:5 ratio as green extraction solvent. The transition of Brilliant Blue FCF to the DES phase occurred on its own, without the need for any reagents such as added salt or tetrahydrofuran. Several crucial factors were tried to get the best extraction efficiency, including species, DES volume and molar ratio, solution pH, ultrasonication, and centrifugation time. Under optimum conditions, extraction recoveries were achieved in the range of 95.1–101.3 % with the method developed for Brilliant Blue FCF. The detection and determination limits were observed to be 4.1 μg l-1 and 12.1 μg l-1, respectively. In addition, the relative standard deviation values for the method's accuracy were found to be 2.23 % and 3.48 % within and between days, respectively. It has been established that the developed method is highly environmentally friendly thanks to the application of the Analytical GREENness (AGREE) and Green Analytical Procedure Index (GAPI) tools. This study shows that DES applications can be carried out without the use of emulsifiers and dispersants by prioritizing the use of hydrophobic DES compounds as environmentally friendly and green extraction solvents in food samples.

Fungi from Antarctic marine sediment: characterization and assessment for textile dye decolorization and detoxification.

Cold-adapted microorganisms can produce enzymes with activity at low and mild temperatures, which can be applied to environmental biotechnology. This study aimed to characterize 20 Antarctic fungi to identify their genus (ITS rDNA marker) and growth temperatures and evaluate their ability to decolorize and detoxify the textile dye indigo carmine (IC). An individual screening was performed to assess the decolorization and detoxification of IC by the isolates, as well as in consortia with other fungi. The isolates were affiliated with seven ascomycete genera: Aspergillus (n = 4), Cosmospora (n = 2), Leuconeurospora (n = 2), Penicillium (n = 3), Pseudogymnoascus (n = 6), Thelebolus (n = 2), and Trichoderma (n = 1). The two isolates from the genus Leuconeurospora were characterized as psychrophilic, while the others were psychrotolerant. The Penicillium isolates were able to decolorize between 60 and 82% of IC. The isolates identified as Pseudogymnoascus showed the best detoxification capacity, with results varying from 49 to 74%. The consortium using only Antarctic ascomycetes (C1) showed 45% of decolorization, while the consortia with the addition of basidiomycetes (C1 + Peniophora and C1 + Pholiota) showed 40% and 50%, respectively. The consortia C1 with the addition of the basidiomycetes presented a lower toxicity after the treatments. In addition, a higher fungal biomass was produced in the presence of dye when compared with the experiment without the dye, which can be indicative of dye metabolization. The results highlight the potential of marine-derived Antarctic fungi in the process of textile dye degradation. The findings encourage further studies to elucidate the degradation and detoxification pathways of the dye IC by these fungal isolates.

Synthesis and Dye Adsorption Dynamics of Chitosan-Polyvinylpolypyrrolidone (PVPP) Composite.

One major environmental issue responsible for water pollution is the presence of dyes in the aquatic environment as a result of human activity, particularly the textile industry. Chitosan-Polyvinylpolypyrrolidone (PVPP) polymer composite beads were synthesized and explored for the adsorption of dyes (Bismarck brown (BB), orange G (OG), brilliant blue G (BBG), and indigo carmine (IC)) from dye solution. The CS-PVPP beads demonstrated high removal efficiency of BB (87%), OG (58%), BBG (42%), and IC (49%). The beads demonstrated a reasonable surface area of 2.203 m2/g and were negatively charged in the applicable operating pH ranges. TGA analysis showed that the polymer composite can withstand decomposition up to 400 °C, proving high stability in harsh conditions. FTIR analysis highlighted the presence of N-H amine, O-H alcohol, and S=O sulfo groups responsible for electrostatic interaction and hydrogen bonding with the dye molecules. A shift in the FTIR bands was observed on N-H and C-N stretching for the beads after dye adsorption, implying that adsorption was facilitated by hydrogen bonding and Van der Waals forces of attraction between the hydroxyl, amine, and carbonyl groups on the surface of the beads and the dye molecules. An increase in pH increased the adsorption capacity of the beads for BB while decreasing OG, BBG, and IC due to their cationic and anionic nature, respectively. While an increase in temperature did not affect the adsorption capacity of OG and BBG, it significantly improved the removal of BB and IC from the dye solution and the adsorption was thermodynamically favoured, as demonstrated by the negative Gibbs free energy at all temperatures. Adsorption of dye mixtures followed the characteristic adsorption nature of the individual dyes. The beads show great potential for applications in the treatment of dye wastewater.