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1.
Anal Sci ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573455

RESUMO

In this work, a novel magnetic covalent organic framework (COF (TpPa-NH2) @ Fe3O4) was prepared via two step by simple solvent method for the extraction of anionic azo dye residues in food. The as-prepared COF (TpPa-NH2) @ Fe3O4 nanocomposite was characterised by scanning electron microscope, transmission electron microscope, Fourier transform-infrared spectroscopy, X-ray diffraction and vibrating sample magnetometer. Before high-performance liquid chromatography with ultraviolet detection (HPLC-UV) determination, it was used as magnetic adsorbent for magnetic solid-phase extraction (MSPE) to extract and pre-concentrate three anionic azo dyes in carbonated beverage samples. The several key extraction and desorption parameters affecting the extraction recovery rate were investigated, including extraction time, pH of the solution, amount of material, adsorption time, elution solvent, pH of elution solvent, type of elution solvent, elution volume and elution time. Under optimised conditions, this method has good linearity between 5 and 500 µg L-1 (correlation coefficient > 0.9986). The limit of detection was 2.3-3.4 µg L-1. The recoveries of the samples were between 87.5 and 96.9%, and the relative standard deviation lower than 4.6%. The developed method has broad application prospects for the analysis of anionic azo dyes in carbonated beverages.

2.
3 Biotech ; 14(3): 93, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38433848

RESUMO

Factors, namely pH, laccase-like activity, dyes concentration as well as 1-Hydroxybenzotriazole (HBT) concentration was examined. The results indicated that the maximum decolorization yield and rate reached 98.30 ± 0.10% and 5.84 ± 0.01%/min, respectively for Sirius Blue, and 99.34 ± 0.47% and 5.85 ± 0.12%/min, respectively for Sirius Red after 4 h. The presence of the redox mediator 1-hydroxybenzotriazole (HBT) greatly improved the decolorization levels. The optimum concentrations of HBT, dyes, and laccase were 0.62 mM, 50 mg/L, and 0.89 U/mL respectively at pH 4.58 for both dyes. Phytotoxicity tests using treated and untreated dyes proved that the applied treatment slightly decreased the toxicity of the by-products. However, the germination index (GI) increased from 14.6 to 36.08% and from 31.6 to 36.96% for Sirius Red and Sirius Blue, respectively. The present study focused on the treatment of two recalcitrant azo dyes, namely: Sirius Blue (Direct Blue 71) and Sirius Red (Direct Red 80). The decolorization was performed using cell-free supernatant from Coriolopsis gallica culture with high laccase activity. Response surface methodology (RSM) and Box-Behnken design were applied to optimize the decolorization of the two tested dyes. The effect of four.

3.
Food Chem Toxicol ; 187: 114585, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38490351

RESUMO

Although concern persists regarding possible adverse effects of consumption of synthetic azo food dyes, the mechanisms of any such effects remain unclear. We have tested the hypothesis that chronic consumption of the food dye Sunset Yellow (SY) perturbs the composition of the gut microbiota and alters gut integrity. Male rats were administered SY orally for 12 weeks. Analysis of fecal samples before and after dye administration demonstrated SY-induced microbiome dysbiosis. SY treatment reduced the abundance of beneficial taxa such as Treponema 2, Anaerobiospirillum, Helicobacter, Rikenellaceae RC9 gut group, and Prevotellaceae UCG-003, while increasing the abundance of the potentially pathogenic microorganisms Prevotella 2 and Oribacterium. Dysbiosis disrupted gut integrity, altering the jejunal adherens junction complex E-cadherin/ß-catenin and decreasing Trefoil Factor (TFF)-3. SY administration elevated LPS serum levels, activated the inflammatory inflammasome cascade TLR4/NLRP3/ASC/cleaved-activated caspase-1 to mature IL-1ß and IL-18, and activated caspase-11 and gasdermin-N, indicating pyroptosis and increased intestinal permeability. The possibility that consumption of SY by humans could have effects similar to those that we have observed in rats should be examined.


Assuntos
Compostos Azo , Microbioma Gastrointestinal , Humanos , Masculino , Ratos , Animais , Ratos Wistar , Disbiose , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Caspases
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124093, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428162

RESUMO

Theoretical computations of pyrimidine-based azo dyes were performed by the DFT approach using the B3LYP/6 - 31G(d,p) basis set. The molecules were optimized based on the same basis set by calculating the minimum energy. FMOs, DOS and GCRD were computed for kinetic stability and chemical reactivity of the selected compounds. The MEP surface was studied to locate nucleophilic and electrophilic attack zones. The energy gap was carefully studied for pyrimidine-based azo dyes. Vibrational spectroscopy was studied in the most prominent regions with respect to PED assignments. Similarly, the UV-Vis absorption technique was calculated using the TD-DFT approach in different solvent media. The electronic structure of each atom in a molecule was examined via the electron localization function (ELF) and localized orbital locator (LOL). Non-covalent interactions were explored using reduced density gradient analysis. The combination of experimental and theoretical data allowed us to correlate the structural modifications with the observed photophysical properties, facilitating the design of azo dyes with tailored characteristics. This work contributes to the fundamental understanding of azo dyes and offers a foundation for the development of new materials with enhanced photophysical and electronic properties.

5.
Acta Histochem ; 126(3): 152154, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479076

RESUMO

Sulfonated azo dyes are crucial for the histochemical, topochemical, and electrophoretic demonstration of proteins. Additionally, these dyes may reveal the significance of evaluating the anisotropic phenomenon of linear dichroism in macromolecularly oriented stained proteins. However, this requires that the ordered -NH3+ groups available for electrostatic binding of the -SO3- dye groups are present in the protein substrate. Further, the reactive -SO3- dye groups should be positioned in a way to permit selective absorption of polarized light at the level of the dye -NN- chromophore azo groups. This review reports the usefulness of sulfonated azo dyes in revealing the extrinsic phenomenon of linear dichroism in dye-substrate complexes and changes in the oriented state of protein macromolecules.

6.
Chemosphere ; 355: 141766, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38527631

RESUMO

Azo dyes are largely used in many industries and discharged in large volumes of their effluents into the aquatic environment giving rise to non-esthetic pollution and health-risk problems. Due to the high stability of azo dyes in ambient conditions, they cannot be abated in conventional wastewater treatment plants. Over the last fifteen years, the decontamination of dyeing effluents by persulfate (PS)-based advanced oxidation processes (AOPs) has received a great attention. In these methods, PS is activated to be decomposed into sulfate radical anion (SO4•-), which is further partially hydrolyzed to hydroxyl radical (•OH). Superoxide ion (O2•-) and singlet oxygen (1O2) can also be produced as oxidants. This review summarizes the results reported for the discoloration and mineralization of synthetic and real waters contaminated with azo dyes covering up to November 2023. PS activation with iron, non-iron transition metals, and carbonaceous materials catalysts, heat, UVC light, photocatalysis, photodegradation with iron, electrochemical and related processes, microwaves, ozonation, ultrasounds, and other processes is detailed and analyzed. The principles and characteristics of each method are explained with special attention to the operating variables, the different oxidizing species generated yielding radical and non-radical mechanisms, the addition of inorganic anions and natural organic matter, the aqueous matrix, and the by-products identified. Finally, the overall loss of toxicity or partial detoxification of treated azo dye solutions during the PS-based AOPs is discussed.


Assuntos
Compostos Azo , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Ferro , Oxirredução , Oxidantes , Água
7.
Sensors (Basel) ; 24(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38339646

RESUMO

Sunset Yellow FCF (SY FCF) is one of the widely used synthetic azo dyes in the food industry whose content has to be controlled for safety reasons. Electrochemical sensors are a promising tool for this type of task. A voltammetric sensor based on a combination of tin and cerium dioxide nanoparticles (SnO2-CeO2 NPs) with surfactants has been developed for SY FCF determination. The synergetic effect of both types of NPs has been confirmed. Surfactants of various natures (sodium lauryl sulfate (SLS), Brij® 35, and hexadecylpyridinium bromide (HDPB)) have been tested as dispersive media. The best effects, i.e., the highest oxidation currents of SY FCF, have been observed in the case of HDPB. The sensor demonstrates a 4.5-fold-higher electroactive surface area and a 38-fold-higher electron transfer rate compared to the bare glassy carbon electrode (GCE). The electrooxidation of SY FCF is an irreversible, two-electron, diffusion-driven process involving proton transfer. In differential pulse mode in Britton-Robinson buffer (BRB) pH 2.0, the sensor gives a linear response to SY FCF from 0.010 to 1.0 µM and from 1.0 to 100 µM with an 8.0 nM detection limit. The absence of an interferent effect from other typical food components and colorants has been shown. The sensor has been tested on soft drinks and validated with the standard chromatographic method.

8.
Int J Mol Sci ; 25(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38255902

RESUMO

Azo dyes are of concern due to their harmful effects on the environment and human health. The oxidation of 2,2'-dihydroxyazobenzene (DHAB) catalyzed with recombinant Coprinus cinereus (rCiP) peroxidase was investigated. The kinetic measurements were performed using the spectrophotometric and fluorimetric methods. The dependences of the initial reaction rates on enzyme, substrate and hydrogen peroxide concentrations during DHAB oxidation were established, and bimolecular constants of enzyme interaction with DHAB were calculated. This research demonstrated that the initial biocatalytic oxidation rates of DHAB depend on the pH and the estimated pKa values of the active forms of rCip. This study's findings thus contribute to a more comprehensive understanding of the biocatalytic oxidation of DHAB, providing valuable data for assessing the long-term toxicity, carcinogenesis and epigenetic effects of azo dyes in the environment.


Assuntos
Agaricales , Peroxidase , Peroxidases , Humanos , Compostos Azo , Biocatálise , Corantes
9.
Molecules ; 29(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38257390

RESUMO

The textile industry produces high volumes of colored effluents that require multiple treatments to remove non-adsorbed dyes, which could be recalcitrant due to their complex chemical structure. Most of the studies have dealt with the biodegradation of mono or diazo dyes but rarely with poly-azo dyes. Therefore, the aim of this paper was to study the biodegradation of a four azo-bond dye (Sirius grey) and to optimize its decolorization conditions. Laccase-containing cell-free supernatant from the culture of a newly isolated fungal strain, Coriolopsis gallica strain BS9 was used in the presence of 1-hydroxybenzotriazol (HBT) to optimize the dye decolorization conditions. A Box-Benken design with four factors, namely pH, enzyme concentration, HBT concentration, and dye concentration, was performed to determine optimal conditions for the decolorization of Sirius grey. The optimal conditions were pH 5, 1 U/mL of laccase, 1 mM of HBT, and 50 mg/L of initial dye concentration, ensuring a decolorization yield and rate of 87.56% and 2.95%/min, respectively. The decolorized dye solution showed a decrease in its phytotoxicity (Germination index GI = 80%) compared to the non-treated solution (GI = 29%). This study suggests that the laccase-mediator system could be a promising alternative for dye removal from textile wastewater.


Assuntos
Compostos Azo , Lacase , Polyporaceae , Compostos Azo/toxicidade , Biodegradação Ambiental , Corantes/toxicidade , Poli A
10.
J Biomol Struct Dyn ; : 1-14, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38284378

RESUMO

The textile industry utilizing affordable azo dyes is a high threat to aquatic life and causes environmental problems due to their toxicity. Biodegradation of azo dyes employing microbes and enzymes has proved to be an efficient method for treating industrial effluent. This study used the novel microbial consortium to decolorize reactive azo dyes (Reactive Red 120; Reactive Black 5 and Reactive Blue 13), and its azo-reductase activity was evaluated. The metagenomic analysis of the consortium identified azo-reductase-producing bacterial species. The molecular docking revealed that PpAzoR from Pseudomonas putida had the highest binding affinities for all the three dyes such as Reactive Black 5 (-9.3 kcal/mol), Reactive Blue 13 (-9.8 kcal/mol) and Reactive Red 120 (-10.7 kcal/mol). The structural rigidity and stability of the docked complex were confirmed through MD simulations evaluated across multiple descriptors from the simulation trajectories. Further, MMPBSA analysis validated the results that binding of the ligands, i.e. dye molecules Reactive Black (RB5), Reactive Blue (RB13) and Reactive Red (RR120) binding with the Azoreductase (PpAzoR) to the screened Azo-dyes was spontaneous. Based on molecular dynamics simulations for 100 ns, RR 120 showed the highest binding affinity (-411.336 ± 46.799 KJ/mol), followed by RB5 (-288.012 ± 33.371 KJ/mol). The dyes (RR120 and RB5) exhibited stable interactions with the target azoreductase (PpAzoR). The present study provides insights that PpAzoR shows the highest decolorization potency, which could be interpreted as a potential dye-degrading protein based on dye-degrading assay findings.Communicated by Ramaswamy H. Sarma.


>90% decolourization observed for all reactive dyes at 72 hAzo reductase-producing bacterial species were identified using metagenomicsPseudomonas putida (PpAzoR) showed maximum binding affinity with all three dyesPositive correlation was established between dye decolourization and in-silico results.

11.
Environ Sci Pollut Res Int ; 31(1): 657-667, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38015401

RESUMO

Azo dyes find applications across various sectors including food, pharmaceuticals, cosmetics, printing, and textiles. The contaminating effects of dyes on aquatic environments arise from toxic effects caused by their long-term presence in the environment, buildup in sediments, particularly in aquatic species, degradation of pollutants into mutagenic or mutagenic compounds, and low aerobic biodegradability. Therefore, we theoretically propose the first steps of the degradation of azo dyes based on the interaction of hydroperoxyl radical (•OOH) with the dye. This interaction is studied by the OC and ON mechanisms in three azo dyes: azobenzene (AB), disperse orange 3 (DO3), and disperse red 1 (DR1). Rate constants calculated at several temperatures show a preference for the OC mechanism in all the dyes with lower activation energies than the ON mechanism. The optical properties were calculated and because the dye-•OOH systems are open shell, to verify the validity of the results, a study of the spin contamination of the ground [Formula: see text] and excited states [Formula: see text] was previously performed. Most of the excited states calculated are acceptable as doublet states. The absorption spectra of the dye-•OOH systems show a decrease in the intensity of the bands compared to the isolated dyes and the appearance of a new band of the type π → π* at a longer wavelength in the visible region, achieving up to 868 nm. This demonstrates that the reaction with the •OOH radical could be a good alternative for the degradation of the azo dyes.


Assuntos
Compostos Azo , Poluentes Químicos da Água , Compostos Azo/toxicidade , Corantes/toxicidade , Alérgenos , Mutagênicos/toxicidade , Poluentes Químicos da Água/toxicidade
12.
Talanta ; 270: 125537, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101036

RESUMO

The use of additives, including dyes, is common in the preparation of food products. The analytical control of artificial food dye content is relevant since some, such as azo dyes, may produce cancer and attention deficit disorders and hyperactivity in children. Consequently, the maximum permitted concentration of azo dyes in food is regulated by current legislation. Therefore, it is of interest to find simple and fast procedures for the control of these compounds. The aim of this study is to determine the concentration of azo dyes in food samples by the Arata-Possetto method - based on the extraction of azo dyes employing natural wool -, followed by the analysis of an image captured by a smartphone camera. After experimentally determining the optimal extraction conditions, the calibration curves for standard solutions of different food dyes and the color of the dyed wool were obtained. Results from dyed wool image processing were compared with the absorbance spectra of the solutions before extraction as measured by a diode array spectrophotometer. The spectrophotometric and the image processing procedures were employed to obtain the calibration curves for different food dyes, which were subsequently employed to analyze food samples. Statistical treatment shows that the results of both methods are comparable.


Assuntos
Corantes , Smartphone , Animais , Criança , Humanos , Corantes/análise , Espectrofotometria , Compostos Azo/análise , Lã/química
13.
Water Environ Res ; 95(12): e10948, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38062884

RESUMO

A notable level of apprehension exists over the adverse impacts of dye pollution on aquatic ecosystems and human well-being. The primary objective of this research is to assess the effectiveness of Fenton catalytic reactions in degrading 14 different commercial azo dyes (both single and double) present in aqueous solutions. The investigation focused on the function of dye structures, using a combination of experimental data and examination of theoretical factors. Dye degradation process was carried out at pH 3, and the concentrations of Fe2+ (10-4 mol/L), H2 O2 (2 × 10-3 mol/L), and dye (0.05 g/L). The findings revealed that dyes with a larger molecular weight were more effective at degrading (D%), with the overall degradation efficiency varying from 0% to 94%. Functional groups played an important role in degradation efficiency; for example, dyes with higher aromatic rings led to less D%, while a higher number of sulfonic, methyl, and nitro groups was responsible for better D%. Notably, the presence of OH groups in the backbone of dyes (AB 24, ABE 113, and MB 9) formed the Fe complex during the catalytic process, and the D% was minimal. On the other hand, theoretical quantum calculations such as the greater the JCLogP, highest occupied molecular orbital, and Dipole moment value, the higher the degradation efficiency. And dyes with low lowest unoccupied molecular orbital tended to have a better degradation efficiency. To some extent, UV-Vis spectral analysis was investigated to determine the degradation pathway, and the pseudo-second-order kinetic model fitted better in the degradation process. The overall experimental and theoretical findings suggested that dye degradation efficiency by the Fenton process is structure-dependent. PRACTITIONER POINTS: Insights into the role of azo dye structures-properties on degradation efficiency. Higher molecular weight and sulfonic groups containing dyes showed better degradation efficiency. Hydroxyl groups play the formation of the Fe complex during the degradation process. Higher values of HOMO and lower values of LUMO enhanced degradation efficiency. The pseudo-second-order (PSO) kinetic model obeyed the Fenton process.


Assuntos
Corantes , Águas Residuárias , Humanos , Corantes/química , Ferro/química , Ecossistema , Peróxido de Hidrogênio/química , Compostos Azo/química
14.
Food Res Int ; 174(Pt 1): 113593, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37986530

RESUMO

Color is a crucial sensory attribute that guides consumer expectations. A high-performance pequi carotenoid extraction process was developed using ionic liquid-based ethanolic solutions and a factorial design strategy to search for a potential substitute for the artificial azo dye yellow tartrazine. All-trans-antheraxanthin was identified with HPLC-PAD-MSn for the first time in pequi samples. [BMIM][BF4] was the most efficient ionic liquid, and the maximization process condition was the solid-liquid ratio R(S/L) of 1:3, the co-solvent ratio R(IL/E) of 1:1 ([BMIM][BF4]: ethanol), and three cycles of extraction with 300 s each and yielded 107.90 µg carotenoids/g of dry matter. The ionic liquid-ethanolic solution recyclability was accomplished by freezing and precipitating with an average recovery of 79 %. In CIELAB parameters, pequi carotenoid extracted with [BMIM][BF4] was brighter and yellower than the artificial azo dye yellow tartrazine. A color change of 11.08 and a hue* difference of 1.26° were obtained. Furthermore, carotenoids extracted with [BMIM][BF4] showed antioxidant activity of 35.84 µmol of α-tocopherol. These findings suggest the potential of employing the pequi carotenoids to replace the artificial azo dye yellow tartrazine in foods for improved functional properties.


Assuntos
Líquidos Iônicos , Tartrazina , Compostos Azo , Carotenoides , Antioxidantes
15.
Ecotoxicol Environ Saf ; 268: 115681, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37976925

RESUMO

Anthraquinone is a redox mediator that can effectively catalyze the degradation of azo dyes by promoting the electron transfer. In this study, a mediator membrane with poly (vinylidene fluoride) (PVDF) as the membrane support and 1,8-dichloroanthraquinone (1,8-AQ) and graphene oxide (GO) as the additives was prepared and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), atomic force microscopy (AFM) and water contact angle. The introduction of GO increases the pure water flux of the membrane to 258.56±12.93 L/(m2·h). Its catalytic performances for the biodegradation of azo dyes were evaluated. Under the optimized conditions, the 1,8-AQ/GO/PVDF composite membrane is able to improve the dye degradation efficiency 2.2 times for reactive red X-3B and 1.1 times for acid red B, as compared with PVDF membrane. In addition, the mediator membrane maintains stable and high catalytic efficiency in the cyclic test and over 90 % dye degradation efficiency is still obtained after 5 cycles of decolorization. These results suggest the great application potentials of the 1,8-AQ/GO/PVDF membrane in the dye wastewater treatment.


Assuntos
Compostos Azo , Água , Água/química
16.
ACS Appl Bio Mater ; 6(10): 4345-4357, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37791902

RESUMO

The emergence of drug-resistant pathogenic microorganisms has become a public health concern, with demand for strategies to suppress their proliferation in healthcare facilities. The present study investigates the physicochemical and antimicrobial properties of carbon dots (CD-MR) derived from the methyl red azo dye. The morphological and structural analyses reveal that such carbon dots present a significant fraction of graphitic nitrogen in their structures, providing a wide emission range. Based on their low cytotoxicity against mammalian cells and tunable photoluminescence, these carbon dots are applied to bioimaging in vitro living cells. The possibility of using CD-MR to generate reactive oxygen species (ROS) is also analyzed, and a high singlet oxygen quantum efficiency is verified. Moreover, the antimicrobial activity of CD-MR is analyzed against pathogenic microorganisms Staphylococcus aureus, Candida albicans, and Cryptococcus neoformans. Kirby-Bauer susceptibility tests show that carbon dots synthesized from methyl red possess antimicrobial activity upon photoexcitation at 532 nm. The growth inhibition of C. neoformans from CD-MR photosensitization is investigated. Our results show that N-doped carbon dots synthesized from methyl red efficiently generate ROS and possess a strong antimicrobial activity against healthcare-relevant pathogens.


Assuntos
Anti-Infecciosos , Fotoquimioterapia , Pontos Quânticos , Animais , Carbono/farmacologia , Carbono/química , Espécies Reativas de Oxigênio , Pontos Quânticos/uso terapêutico , Pontos Quânticos/química , Fotoquimioterapia/métodos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Compostos Azo/farmacologia , Compostos Azo/uso terapêutico , Mamíferos
17.
Environ Res ; 238(Pt 2): 117202, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37769832

RESUMO

Due to their widespread application in water purification, there is a significant interest in synthesising nanoscale photocatalysts. Nanophotocatalysts are primarily manufactured through chemical methods, which can lead to side effects like pollution, high-energy usage, and even health issues. To address these issues, "green synthesis" was developed, which involves using plant extracts as reductants or capping agents rather than industrial chemical agents. Green fabrication has the benefits of costs less, pollution reduction, environmental protection and human health safety, compared to the traditional methods. This article summarises recent advances in the environmentally friendly synthesis of various nanophotocatalysts employed in the degradation of azo dyes. This study compiles critical findings on natural and artificial methods to achieve the goal. Green synthesis is constrained by the time and place of production and issues with low purity and poor yield, reflecting the complexity of plants' geographical and seasonal distributions and their compositions. However, green photocatalyst synthesis provides additional growth opportunities and potential uses.


Assuntos
Compostos Azo , Extratos Vegetais , Humanos , Extratos Vegetais/química , Corantes/química
18.
Food Chem X ; 18: 100713, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37397211

RESUMO

This study aims to develop and validate a method for simultaneously measuring three azo dyes (azorubine, brilliant black BN, lithol rubine BK) not designated in Korea. The HPLC-PDA analysis method was validated based on the ICH guidelines, and the color stability was evaluated. The milk and cheese samples were spiked with azo dyes, the correlation coefficient of calibration curve ranged from 0.999 to 1.000 and the recovery rates of azo dyes were 98.81 âˆ¼ 115.94%, with RSD of 0.08 âˆ¼ 3.71%. The LOD and the LOQ in milk and cheese ranged from 1.14 to 1.73 µg/mL and 3.46 to 5.25 µg/mL, respectively. In addition, the expanded uncertainties of the measurements ranged from 3.3421 to 3.8146%. The azo dyes appeared to be color stable for more than 14 days. The results indicate that this analytical method is suitable for extracting and analyzing azo dyes in milk and cheese samples, which are not permitted in Korea.

19.
Environ Monit Assess ; 195(8): 929, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37432473

RESUMO

The majority of textile wastes are made up of toxic dyes. Additionally, because these compounds are soluble, wastewater may include significant concentrations. In this work, the green alga Lychaete pellucida is used for the bioremoval of four common azo dyes, Reactive Blue 4 (RB4), Reactive Red 120 (RR120), Reactive Brilliant Yellow 3G (RBY3G), and Reactive Green12 (RG12), with the application of two models of sorption isotherms, Langmuir and Freundlich. The spectrophotometer method was used to identify optimum conditions (temperature, pH, dye concentrations, algal biomass, and contact time) to remove these dyes onto dry freshwater macroalgae. The optimum pH for L. pellucida was 8. The optimum biosorbent amount is 2 g/L. Then, the best-removed dye concentration was 5 mg/L, the optimum contact duration was 120 min, and the optimum temperature was 25 °C. Under optimum conditions, the percent of dye removal was about 95% for all used azo dyes. This is the first report on the use of Lychaete pellucida for the efficient biodegradation of hazardous azo dyes.


Assuntos
Clorófitas , Alga Marinha , Monitoramento Ambiental , Compostos Azo , Corantes
20.
Saudi J Biol Sci ; 30(8): 103734, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37483839

RESUMO

In the present investigation, two fungal strains were exploited to evaluate their degradation capability on Synozol Red, Yellow, and Navy-Blue dyes which gave the utmost decolorization such as 40%, 70%, 90% by Aspergillus niger, and 36%, 73%, 87% by Trichoderma viride, respectively for 60 days. The Gas Chromatography-Mass Spectrometry (GC-MS) analysis of the decolorized dyes suggested that various compounds such as Caprolactam, Furazan-3-carboxamide, oxime, 4-amino-N, N-dimethyl, 6H-Pyrazolo[1,2-a] [1,2,4,5]tetrazine, Hexahydro-2,3-dimethyl, Benzene, 1-propenyl, Dihydroxymaleic acid, Arsenous acid, tris(trimethylsilyl) ester were produced by the fungi which helped in the removal of dyes from the wastewater. The laccase activity of the degraded dyes was proof that both of the strains positively produced the enzyme that helped in the biodegradation of carcinogenic dyes into less harmful products. The A. niger extracted laccase relative activity was 262%, 265%, and 145.7% for Synozol Yellow, Synozol Red, and Navy Blue, respectively. Similarly, laccase, obtained from T. viride, showed relative activity of 187.5% against Synozol Yellow, 215% against Synozol Red, and 202% against Navy Blue. Furthermore, the supernatant extracted from fungi-decolorized wastewater was used to check phytotoxicity on Vigna radiata, which gave excellent results. Both fungal strains, on the basis of their dye degradation potential, can be used to ameliorate wastewater contaminated with azo dyes.

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