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1.
Environ Sci Pollut Res Int ; 31(49): 58905-58927, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39322931

RESUMO

Industrial effluents, especially those containing dyes, have become the main cause of contamination of water resources. In this context, Brazilian bentonite/MgO composites, with excellent adsorptive properties, were prepared and investigated for their effectiveness in removing cationic and anionic dyes from aqueous solutions. The new adsorbents were obtained using Brazilian bentonites and MgO using the mechanochemical method followed by heat treatment (at 700 °C for 4 h). Different characterization techniques were used for the chemical, mineralogical, thermal, surface, and morphological analysis of the raw clays and the composites. The experimental adsorption isotherms were quantified under different conditions of initial concentration, contact time, pH, adsorbent dosage, and temperature variation to interpret the adsorption mechanism of the crystal violet (CV) and Congo red (CR) dyes. The modeling results were obtained from the empirical Sips equation and Pseudo Second Order (PSO) kinetics, indicating that the adsorption of molecules is a heterogeneous phenomenon that occurs in a monolayer on the surface (ns > 1), with the adsorption rate determined by chemisorption. The composites showed the best removal efficiency performance compared to the raw bentonites, with an increase of 12% for the CV dye and 46% for the CR dye. In addition, the qmax values obtained were 423.02 mg/g and 479.86 mg/g (AM01). This research underscores the potential of Brazilian bentonite/MgO composites as a promising solution for the removal of cationic and anionic dyes from water, offering hope for future applications in the field of environmental engineering and materials science.


Assuntos
Bentonita , Corantes , Poluentes Químicos da Água , Bentonita/química , Adsorção , Corantes/química , Brasil , Poluentes Químicos da Água/química , Óxido de Magnésio/química , Cinética , Cátions , Ânions
2.
Food Chem ; 460(Pt 2): 140553, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39126739

RESUMO

In Chile, limited information is available on colorants in commonly consumed foods among vulnerable age groups. We developed and validated a rapid HPLC-DAD method to simultaneously evaluate 11 synthetic colorants in candies, beverages, ice cream, and cereals. The method exhibited excellent analytical performance for all 11 colorants with LOD (0.44 - 1.55 mgL-1), LOQ v(1.32 - 4.70 mgL-1), precision (4.0 and 7.3% RSD), and recovery (80 - 105%) in fortified matrices (10-50-100 mgL-1). The highest detection frequencies were as follows: cereals > candies > beverages > ice cream. Sunset Yellow was the most prevalent colorant in all food matrices, followed by Allura Red and Azorubine. Positive samples contained between 1 and 5 synthetic colorants. With the exception of cereals, the colorant concentrations in the remaining matrices exceeded the Codex Alimentarius regulations and the values reported in other studies worldwide, indicating the Chilean population is at risk.


Assuntos
Corantes de Alimentos , Cromatografia Líquida de Alta Pressão , Chile , Corantes de Alimentos/análise , Grão Comestível/química , Bebidas/análise , Doces/análise , Sorvetes/análise , Contaminação de Alimentos/análise
3.
J Hazard Mater ; 478: 135425, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39137543

RESUMO

In vitro plant cultures are able to remove and metabolise xenobiotics, making them promising tools for decontamination strategies. In this work, we evaluated Brassica napus hairy roots (HRs) to tolerate and remove high concentrations of the azo dye Naphthol Blue-Black (NBB). Experiments were performed using both growing and resting culture systems at different pHs. Reuse of HRs biomass was evaluated in successive decolourisation cycles. Proteomics was applied to understand the molecular responses likely to be involved in the tolerance and removal of NBB. The HRs tolerated up to 480 µg mL-1 NBB, and 100 % removal was achieved at 180 µg mL-1 NBB after 10 days using both culture systems. Interestingly, the HRs are robust enough to be reused, showing 55-60 % removal even after three reuse cycles. The highest dye removal rates were achieved during the first 2 days of incubation, as initial removal is mainly driven by passive processes. Active mechanisms are triggered later by regulating the expression of proteins with different biological functions, mainly those related to xenobiotic metabolism, such as hydrolytic and redox enzymes. These results suggest that B. napus HRs are a robust tool that could make a significant contribution to textile wastewater treatment.


Assuntos
Biodegradação Ambiental , Brassica napus , Raízes de Plantas , Proteômica , Brassica napus/metabolismo , Raízes de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Corantes/metabolismo , Corantes/química , Compostos Azo/metabolismo , Compostos Azo/química , Poluentes Químicos da Água/metabolismo
4.
Int J Biol Macromol ; 277(Pt 1): 134063, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39038565

RESUMO

More sustainable materials have been becoming an important concern of worldwide scientists, and cellulosic materials are one alternative in water decontamination. An efficient strategy to improve removal capacity is functionalizing or incorporating nanomaterials in cellulose-based materials. The new hybrid cDAC/ZnONPs was produced by green synthesis of zinc oxide nanoparticles (ZnONPs), promoting the in situ reduction and immobilization on the cationic dialdehyde cellulose microfibers (cDAC) surface to remove Congo red dye from water. cDAC/ZnONPs was characterized by scanning electron microscopy (SEM-EDS) and infrared spectroscopy (FTIR), which showed efficient nanoparticles reduction. Adsorption efficiency on cationic cellulose surface was investigated by pH, contact time, initial concentration, and dye selectivity tests. The material followed the H isotherm model, which resulted in a maximum adsorption capacity of 1091.16 mg/g. Herein, was developed an efficient and ecologically correct new adsorbent, highly effective in Congo red dye adsorption even at high concentrations, suitable for the remediation of contaminated industrial effluents.


Assuntos
Vermelho Congo , Poluentes Químicos da Água , Purificação da Água , Óxido de Zinco , Óxido de Zinco/química , Vermelho Congo/química , Vermelho Congo/isolamento & purificação , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Purificação da Água/métodos , Química Verde , Concentração de Íons de Hidrogênio , Celulose/química , Celulose/análogos & derivados , Corantes/química , Nanopartículas/química , Cinética , Nanopartículas Metálicas/química , Celulose Oxidada/química , Cátions/química
5.
Chemosphere ; 363: 142825, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38996982

RESUMO

Electrochemical oxidation (EO), electro-Fenton (EF), and photoelectro-Fenton (PEF) with a BDD anode have been comparatively assessed to remediate solutions of Red CL and/or Red WB azo dyes from real raw water. For the EO process in 50 mM Na2SO4 at pH 3.0, the main oxidant was the heterogeneous •OH generated at the anode, whereas in EF and PEF, the cathodic production of H2O2 and the addition of 0.50 mM Fe2+ catalyst additionally originated homogeneous •OH that enhanced the oxidation of organics. In PEF, the solution was illuminated with a 6 W UVA light. An almost total discoloration was always found operating with a 1:1 mixture of 200 mg L-1 of both dyes in 60 min, whose efficiency increased in the order of EO < EF < PEF. The HPLC analysis of the dye mixture treated by PEF disclosed that its degradation process agreed with its discoloration. A high 74% of COD was reduced due to the oxidative action of hydroxyl radicals and the photolysis of final Fe(III)-carboxylate species with UVA irradiation. The process was accompanied by an energy consumption of 0.76 kWh (g COD)-1, a value similar to the energy consumed by the applied UVA light.


Assuntos
Compostos Azo , Boro , Corantes , Diamante , Eletrodos , Oxirredução , Poluentes Químicos da Água , Corantes/química , Poluentes Químicos da Água/química , Boro/química , Compostos Azo/química , Diamante/química , Peróxido de Hidrogênio/química , Curtume , Técnicas Eletroquímicas , Fotólise , Raios Ultravioleta , Eliminação de Resíduos Líquidos/métodos , Ferro/química
6.
Sci Rep ; 14(1): 16513, 2024 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019972

RESUMO

The study of diffusion in biological materials is crucial for fields like food science, engineering, and pharmaceuticals. Research that combines numerical and analytical methods is needed to better understand diffusive phenomena across various dimensions and under variable boundary conditions within food matrices. This study aims to bridge this gap by examining the diffusion of substances through biological materials analytically and numerically, calculating diffusivity and conducting surface analysis. The research proposes a process for sweetening Bing-type cherries (Prunus avium) using sucrose/xylitol solutions and a staining technique utilising erythrosine and red gardenia at varying concentrations (119, 238 and 357 ppm) and temperatures (40, 50 and 60 °C). Given the fruit's epidermis resistance, the effective diffusivities of skin were inferior to those in flesh. Temperature and concentration synergise in enhancing diffusion coefficients and dye penetration within the food matrix (357 ppm and 60 °C). Red gardenia displayed significant temperature-dependent variation (p = 0.001), whereas erythrosine dye remained stable by temperature changes (p > 0.05). Gardenia's effective diffusivities in cherry flesh and skin, at 357 ppm and 60 °C, 3.89E-08 and 6.61E-09 m2/s, respectively, significantly differed from those obtained at lower temperatures and concentrations. The results highlight the temperature-concentration impacts on mass transfer calculations for food colouring processes and preservation methodologies.


Assuntos
Temperatura , Difusão , Frutas/química , Frutas/metabolismo , Eritrosina/química , Sacarose/química , Sacarose/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-38928929

RESUMO

This study addressed the harmful effects of artificial colors in pediatric populations, including children diagnosed with Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD), as well as those without behavioral disorders. There is a consensus that synthetic food colorings have several impacts on consumers, especially pediatrics, due to their influence on sensory appeal, which can encourage preference for certain foods. The results revealed that these color additives are directly linked to a series of health problems, with a greater impact on children, including a predisposition to pathological conditions such as carcinogenic, allergenic, mutagenic, cytotoxic, and clastogenic activities, as well as gastrointestinal and respiratory problems, in addition to behavioral changes in children with and without diagnosed disorders. The harms of synthetic dyes in children with or without comorbidities are worrying and require a careful and proactive approach from parents, caregivers and public authorities.


Assuntos
Saúde da Criança , Corantes de Alimentos , Humanos , Criança , Corantes de Alimentos/efeitos adversos , Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Espectro Autista , Pré-Escolar
8.
Materials (Basel) ; 17(12)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38930376

RESUMO

This is the first study of non-woven fabrics elaborated by melt-blowing from polymer nanocomposites made of Nylon 6 and nanoclay (Cloisite 20A) modified with an amine (1,4 diaminobutane dihydrochloride). Morphological and physical characteristics, adsorption capacity, and antibacterial properties are presented. From the X-ray diffraction (XRD) results, it was possible to observe a displacement of the signals to other 2θ angles, due to an α to ϒ phase shift. The scanning electron microscopy (SEM) images showed that the mean diameter of fiber decreased as the content of nanoclay increased. The mechanical tests showed that the tear strength force of neat nylon was 1.734 N, but this characteristic increased to 2.135 N for the sample with 0.5% modified nanoclay. The inulin adsorption efficiency of the Nylon 6/C20A 1.5% and Nylon 6/C20A 2% samples at 15 min was 75 and 74%, respectively. The adsorption capacity of Nylon 6/C20A 1.5% and Nylon 6/C20A 2% for methylene blue and methyl orange remained above 90% even after four adsorption cycles. In addition, non-woven fabrics present antibacterial activity against E. coli.

9.
Electrophoresis ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38794968

RESUMO

This study introduces a novel method for the quantification of malachite green (MG), a pervasive cationic dye, in surface water by synergizing multiphase electroextraction (MPEE) with digital image analysis (DIA) and partial least square discriminant analysis. Aimed at addressing the limitations of conventional DIA methods in terms of quantitation limits and selectivity, this study achieves a significant breakthrough in the preconcentration of MG using magnesium silicate as a novel sorbent. Demonstrating exceptional processing efficiency, the method allows for the analysis of 10 samples within 20 min, exhibiting remarkable sensitivity and specificity (over 0.95 and 0.90, respectively) across 156 samples in both training and test sets. Notably, the method detects MG at low concentrations (0.2 µg L-1) in complex matrices, highlighting its potential for broader application in environmental monitoring. This approach not only underscores the method's cost-effectiveness and simplicity but also its precision, making it a valuable tool for the preliminary testing of MG in surface waters. This study underscores the synergy among MPEE, DIA, and chemometric tools, presenting a cost-efficient and reliable alternative for the sensitive detection of water contaminants.

10.
Molecules ; 29(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38731445

RESUMO

Reducing high concentrations of pollutants such as heavy metals, pesticides, drugs, and dyes from water is an emerging necessity. We evaluated the use of Luffa cylindrica (Lc) as a natural non-conventional adsorbent to remove azo dye mixture (ADM) from water. The capacity of Lc at three different doses (2.5, 5.0, and 10.0 g/L) was evaluated using three concentrations of azo dyes (0.125, 0.250, and 0.500 g/L). The removal percent (R%), maximum adsorption capacity (Qm), isotherm and kinetics adsorption models, and pH influence were evaluated, and Fourier-transform infrared spectroscopy and scanning electron microscopy were performed. The maximum R% was 70.8% for 10.0 g L-1Lc and 0.125 g L-1 ADM. The Qm of Lc was 161.29 mg g-1. Adsorption by Lc obeys a Langmuir isotherm and occurs through the pseudo-second-order kinetic model. Statistical analysis showed that the adsorbent dose, the azo dye concentration, and contact time significantly influenced R% and the adsorption capacity. These findings indicate that Lc could be used as a natural non-conventional adsorbent to reduce ADM in water, and it has a potential application in the pretreatment of wastewaters.


Assuntos
Compostos Azo , Corantes , Luffa , Poluentes Químicos da Água , Purificação da Água , Luffa/química , Compostos Azo/química , Compostos Azo/isolamento & purificação , Adsorção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Cinética , Corantes/química , Concentração de Íons de Hidrogênio , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
11.
Int J Mol Sci ; 25(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612800

RESUMO

Synthetic dyes are persistent organic environmental pollutants that can cause extensive damage to living beings and to the ecosystem as a whole. Cost-effective, sustainable, and efficient strategies to deal with this type of pollution are necessary as it commonly resists conventional water treatment methods. Silver nanoparticles (AgNPs) synthesized using the aqueous extract from the leaves, stem, and fruits of Leucaena leucocephala (Leucena) were produced and characterized through UV-vis, TEM, EDS, SDL, XPS, XRD, and zeta potential, and they proved to be able to promote adsorption to remediate methylene blue and tartrazine pollution in water. The nanoremediation was performed and did not require direct exposure to sunlight or any special lamp or a specific reduction agent. The AgNPs produced using the extract from the leaves exhibited the best performance in nanoremediation and also presented antioxidant activity that surpassed the one from butylated hydroxytoluene (BHT). Consequently, it is an interesting nanotool to use in dye nanoremediation and/or as an antioxidant nanostructure.


Assuntos
Frutas , Nanopartículas Metálicas , Antioxidantes/farmacologia , Ecossistema , Prata , Corantes
12.
Future Microbiol ; 19(7): 607-619, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38530362

RESUMO

Dye application for parasite highlighting in the Ova and Parasite exam is a common practice in parasitology diagnosis. Methods: A scoping review investigated how staining solutions interact with parasite structures. After screening 1334 papers, 35 met eligibility criteria. Results: Differentiating background from foreground in the fecal smear under light microscopy is the core of the research on this topic. Refractivity, unevenness of staining, size and temperature were explored to enhance staining protocols. Cryptosporidium spp. and Microsporidia were the main studied species. Conclusion: Studies on diagnostic efficacy outperform those that elucidate the physical-chemical interaction between dyes and parasites. An alternative approach involves technicians using computational tools to reduce subjectivity in fecal smear interpretation, deviating from conventional methods.


What is this article about? Coloring parasites during fecal exams has been widely used to find parasites in human feces. We searched for articles that could help us to answer the question: 'How do dyes give color to parasites?'. Then, we filtered the information from a total of 1334 articles to 35.What were the results? Cryptosporidium spp. and Microsporidia are microbes that can be seen only through a microscope. Researchers were interested in these two species in the last 40 years. Differentiating parasites from dirt on a glass slide is the main problem researchers are trying to solve. The way the light goes through parasites under a microscope, variation of staining, size and temperature of dyes have been explored to identify what gives better results in coloring protocols.What do the results of the study mean? Little is known about the chemical interaction between dyes and parasites. On the other hand, there are many studies on how good coloring methods are and comparing protocols. An alternative to the conventional approaches in staining parasites is the use of computational tools to reduce doubt in the exam interpretation by technicians.


Assuntos
Corantes , Fezes , Parasitologia , Coloração e Rotulagem , Fezes/parasitologia , Coloração e Rotulagem/métodos , Humanos , Parasitologia/métodos , Corantes/química , Animais , Cryptosporidium/isolamento & purificação , Microsporídios/isolamento & purificação , Microscopia/métodos , Parasitos/isolamento & purificação
13.
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
14.
Environ Sci Pollut Res Int ; 31(41): 53671-53690, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38158527

RESUMO

The removal of dyes from effluents of textile industries represents a technological challenge, due to their significant environmental impact. The application of halloysite (Hal) and palygorskite (Pal) clay minerals as adsorbents for the removal of Congo red (CR) and methylene blue (MB) was evaluated in this work. The materials were applied both in natural and acid-treated forms, and characterized by XRD, XPS, SEM-EDS, FTIR, and N2 adsorption-desorption isotherm techniques to identify their properties and main active sites. The adsorbents showed potential to remove CR (> 98%) and MB (> 85%) within 180 min, using 0.3 g adsorbent and initial dye concentration of 250 mg L-1. Semi-empirical quantum mechanical calculations (SQM) confirmed the interaction mechanism between dyes and the adsorbents via chemisorption (- 69.0 kcal mol-1 < Eads < - 28.8 kcal mol-1), which was further observed experimentally due to the high fit of adsorption data to pseudo-second order kinetic model (R2 > 0.99) and Langmuir isotherm (R2 > 0.98). The use of Pal and Hal to remove dyes was proven to be economically and environmentally viable for industrial application.


Assuntos
Argila , Corantes , Compostos de Silício , Poluentes Químicos da Água , Adsorção , Argila/química , Corantes/química , Poluentes Químicos da Água/química , Compostos de Silício/química , Minerais/química , Azul de Metileno/química , Silicatos de Alumínio/química , Compostos de Magnésio/química , Cinética , Vermelho Congo/química
15.
Environ Sci Pollut Res Int ; 31(4): 5209-5220, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38110688

RESUMO

A promissory technic for reducing environmental contaminants is the production of biochar from waste reuse and its application for water treatment. This study developed biochar (CWb) and NH4Cl-modified biochar (MCWb) using cassava residues as precursors. CWb and MCWb were characterized and evaluated in removing dyes (Acid Blue 9 and Food Red 17) in a binary system. The adsorbent demonstrated high adsorption capacity at all pH levels studied, showing its versatility regarding this process parameter. The equilibrium of all adsorption experiments was reached in 30 min. The adsorption process conformed to pseudo-first-order kinetics and extended Langmuir isotherm model. The thermodynamic adsorption experiments demonstrated that the adsorption process is physisorption, exhibiting exothermic and spontaneous characteristics. MCWb exhibited highly efficient and selective adsorption behavior towards the anionic dyes, indicating maximum adsorption capacity of 131 and 150 mg g-1 for Food Red 17 and Acid Blue 9, respectively. Besides, MCWb could be reused nine times, maintaining its original adsorption capacity. This study demonstrated an excellent adsorption capability of biochars in removing dyes. In addition, it indicated the recycling of wastes as a precursor of bio composts, a strategy for utilization in water treatment with binary systems. It showed the feasibility of the reuse capacity that indicated that the adsorbent may have many potential applications.


Assuntos
Compostos Azo , Benzenossulfonatos , Celulose , Manihot , Poluentes Químicos da Água , Corantes/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Carvão Vegetal/química , Adsorção , Cinética
16.
Arq. bras. oftalmol ; Arq. bras. oftalmol;87(3): e2022, 2024. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550036

RESUMO

ABSTRACT Purpose: This study aimed to investigate the effect of upper eyelid blepharoplasty with the removal of the skin and a strip of orbicularis oculi muscle on the ocular surface, tear film, and dry eye-related symptoms. Methods: Twenty-two eyes of 22 consecutive patients operated by a single surgeon (21 females; mean age, 61 years; age range, 41-75 years) were included. All subjects completed the Ocular Surface Disease Index questionnaire, underwent in vivo confocal microscopy, tear film breakup time measurements, the Schirmer test with anesthesia, and fluorescein and lissamine green staining measurements before, 1 month, and 6 months after upper blepharoplasty alone with preseptal orbicularis excision. Results: A significant increase in Ocular Surface Disease Index, and corneal fluorescein and lissamine green staining and a significant decrease in tear film breakup time were observed after 1 month (p=0.003, p=0.004, p=0.029, and p=0.024 respectively) and 6 months (p=0.001 for all findings). No significant difference in the Schirmer test score was observed during the follow-up. None of the in vivo confocal microscopy parameters showed significant changes during the study. Conclusions: An increase in dry eye symptoms and a decrease in tear film stability along with ocular surface staining were observed in patients undergoing upper eyelid blepharoplasty.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38055167

RESUMO

Nano-biocomposite hydrogel samples were produced using graphene oxide (GO) and agar and applied as adsorbents of organic components in water. The hydrogels were prepared by varying the wt% of Agar and GO. The samples were characterized, and batch adsorption experiments evaluated the effect of initial pH, equilibrium isotherms, and kinetics for the adsorption of the anionic dye Acid Orange 7 (AO) and the cationic dyes Nile Blue A (NB) and methylene blue (MB) in an aqueous medium. Overall, both hydrogel samples exhibited satisfactory results for removing NB and MB; however, there was no effective removal for the anionic dye AO. Adsorption equilibrium isotherms were obtained, and Freundlich, Langmuir, and Sips models were fitted to the experimental equilibrium data; moreover, kinetic data were adjusted to driving force models and particle mass balance. The maximum experimental adsorption capacities, 141.48 mg·g-1 (MB) and 284.69 mg·g-1 (NB), were obtained, on a dry basis, for the sample produced with 70 wt% of agar and 30 wt% of GO. Both hydrogels exhibited remarkable regenerative potential for NB and MB, with the adsorption capacity remaining constant, even after five adsorption/desorption cycles.

18.
Biol Trace Elem Res ; 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37968491

RESUMO

Hair is good bioindicator of exposure, due to its ability to store and retain trace elements for long periods of time. But it can be especially useful when hair dyes are used since they may contain potentially toxic salts in their composition. In this context, analytical methods for the determination of bismuth, cadmium, lead, and silver in scalp human hair by electrothermal atomic absorption spectrometry were successfully validated. A total of 60 samples obtained from women between 18 and 60 years were analyzed: 34 dyed hairs and 26 untreated hairs (control). Average results expressed in dry weight (dyed/control) for each element were 2.34/0.49 µg g-1 (silver), 0.142/0.139 µg g-1 (bismuth), 0.055/0.054 µg g-1 (cadmium), and 2.09/0.99 µg g-1 (lead), respectively. These results agreed with those previously reported for non-exposed populations. A statistically significant higher Ag concentration in dyed hairs was observed, suggesting the bioaccumulation of this element. The associations between metal concentration and variables of interest (age, education, smoking habit, dye brand, use of dietary supplements) were investigated. A strong Pearson correlation was found for the pair Ag/Pb (r = 0.494, p < 0.05). Also, strong associations between lead levels and all the selected variables were observed (p < 0.05), while strong associations between silver levels with age and dye brand and association between cadmium levels and smoking habit were found. Furthermore, several commercial hair dye brands were analyzed to verify compliance with cosmetic regulations. This constitutes the first study of such characteristics performed in Uruguay, with worldwide relevance.

19.
Foods ; 12(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38002124

RESUMO

Flowers have played a significant role in society, focusing on their aesthetic value rather than their food potential. This study's goal was to look into flowering plants for everything from health benefits to other possible applications. This review presents detailed information on 119 species of flowers with agri-food and health relevance. Data were collected on their family, species, common name, commonly used plant part, bioremediation applications, main chemical compounds, medicinal and gastronomic uses, and concentration of bioactive compounds such as carotenoids and phenolic compounds. In this respect, 87% of the floral species studied contain some toxic compounds, sometimes making them inedible, but specific molecules from these species have been used in medicine. Seventy-six percent can be consumed in low doses by infusion. In addition, 97% of the species studied are reported to have medicinal uses (32% immune system), and 63% could be used in the bioremediation of contaminated environments. Significantly, more than 50% of the species were only analysed for total concentrations of carotenoids and phenolic compounds, indicating a significant gap in identifying specific molecules of these bioactive compounds. These potential sources of bioactive compounds could transform the health and nutraceutical industries, offering innovative approaches to combat oxidative stress and promote optimal well-being.

20.
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
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