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1.
Environ Sci Pollut Res Int ; 30(58): 122262-122273, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37968482

RESUMO

Agricultural waste is an unwanted material that is not only unmarketable, but also has secondary costs such as environmental pollution. Oleaster, also known as olive Russian fruit, has various uses, but it also produces waste such as seeds and peels. Oleaster fruit and all its parts are tannin rich, which can be utilized as natural mordant. Improvement of fastness and color properties of natural dyed fibers is obtained by using mordant. The employing of this mordant is effective in reducing agricultural waste and the production of dyeing chemical waste. Reseda extract was utilized as natural dye to investigate the color characteristics. The study of the phenolic percentage of different components of the Oleaster fruit, including peel, seed, and flesh, showed that each of these materials can be used as natural mordant. The formation of physical bonds in the presence of all kinds of mordant was investigated using the FTIR method, and the results showed that their performance is similar and they are effective in surface treatment of wool. Investigation of color characteristics of the yarns showed that the color strength increases in the presence of mordant. Studying the fastness of yarns dyed with ISO methods showed that the samples have high washing fastness.


Assuntos
Corantes , Elaeagnaceae , , Animais , Corantes/química , Poluição Ambiental , Sementes , Taninos/análise , Lã/química , Elaeagnaceae/química
2.
Environ Sci Pollut Res Int ; 29(33): 50608-50616, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35233674

RESUMO

To reduce environmental pollution, it is essential to use green processes in dyeing and meet its requirements. Most natural dyes have a low affinity to be used in the dyeing process. To refine this limitation, the mordanting flow is necessary for many dyeing cases. Pumpkin extract as a natural, metal-rich source can be used as a bio-mordant in green dyeing of natural yarns such as wool. Two natural dyes native to Iran, Reseda luteola and madder, were employed in this study. The effectiveness of bio-mordant presence on yarns was evaluated by FTIR-ATR test from mordanted and mordanted-dyed wool samples. The study of K/S (color strength) content of dyed samples showed that increasing the dye concentration increases the amount of K/S. Fastness performance of wool dyed with pumpkin alternated from good to excellent depending on natural dye type and concentration, due to the formation of complex structures.


Assuntos
Corantes , Cucurbita , Animais , Corantes/química , Extratos Vegetais/química , Têxteis , Lã/química
3.
J Food Sci ; 87(2): 585-598, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34997936

RESUMO

Enhanced thermal stability of anthocyanins from black barberry was obtained using an optimum concentration of Angum gum (AG) and cress seed gum (CSG). To this goal initially, the phytochemical characteristics, and the thermal stability of purified and non-purified anthocyanins were investigated to perceive the effect of the purification process. Then the effect of each gum and its concentration was evaluated on the thermal degradation kinetics of anthocyanins. Results demonstrated that both gums enhanced the thermal stability of anthocyanins, while CSG had a superior effect. Findings also revealed that the half-life of anthocyanin was increased at 60°C from 366 ± 22.8 to 432 ± 4.2 and 636 ± 52.8 min in presence of AG and CSG, respectively. TGA results confirmed that the presence of SF-AG and CSG in their optimum concentration enhanced the heat stability of anthocyanin extract. Also, physical molecular bondings were confirmed by the FTIR spectrums where some peaks attributed to both of the extract and the gums were shifted. Plateau or flake-like micro-particles were detected by SEM which correspond with the most freeze-dried microcapsules. PRACTICAL APPLICATION: The results of this study may contribute to the enhanced thermal stability of anthocyanins from barberry that can be used as a coloring agent in beverage and food systems. Moreover, it can be used in preparation of natural nutraceuticals and pharmaceuticals.


Assuntos
Antocianinas , Brassicaceae , Liofilização , Polissacarídeos , Sementes
4.
Environ Sci Pollut Res Int ; 28(6): 7249-7260, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33029769

RESUMO

Textile and dyeing are one of the most significant industries in many states. The employing of natural dyes in dyeing procedure is very important due to the environmental security of the area. To obtain a green, clean, and environmentally friendly dyeing of yarns, two natural dyes of madder and weld, which are native to Iran, were employed for dyeing yarns for carpet preparation. Due to the low affinity of natural dyes and maintaining the biocompatibility of the dyeing process, the oak was used as a new tannin rich mordant. The ultrasound-microwave-assisted method in water solution was used for extraction, and yield to the process was obtained about 27, 32, and 36% for madder, weld, and oak, respectively. The extractions were analyzed by UV-Visible and SEM techniques, and the ash, humidity, and density properties of these were investigated. The pre-mordanting method was employed for this study, and ferrous sulphate was used for compare of natural mordant performance. The washed, mordanted, and dyed yarns were investigated by analytical techniques, and the accuracy of these processes was confirmed. The fastness properties as well as the colorimetric characteristics of dyed yarns were assessed using related standards, and the dyed yarns have acceptable performance and could compete with metal mordant, colorimetrically.


Assuntos
Corantes , Quercus , Animais , Irã (Geográfico) , Têxteis ,
5.
Int J Biol Macromol ; 164: 3349-3360, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32882277

RESUMO

This study aimed to characterize novel complex coacervates based on Zedo gum and cress seed gum as natural polysaccharides with gelatin (type-A and type-B) as potential wall materials for encapsulation of anthocyanins. The coacervates were prepared under optimum conditions (pH and gum to gelatin ratio), freeze-dried, and the resulted powders were analyzed in terms of thermal stability, morphology, and molecular interactions. The thermogravimetric analysis revealed that molecular interaction between polysaccharides and gelatins led to enhance the thermal stability of gums. The morphology of coacervates showed that while ZG-gelatin and CSG-gelatin coacervates resulted in cubic and irregular particles, freeze-drying severely changed the morphology of coacervates. Moreover, SEM images at lower magnification showed big voids for lyophilized coacervates, while SEM images confirmed a compact and dense microstructure of coacervates at higher magnification and BET method. Also, the molecular interaction of polysaccharides and gelatin in aqueous media was assessed using Raman spectroscopy. Furthermore, findings showed that the type-A of gelatin is a more suitable protein to form coacervates with polysaccharides. In the next step, natural anthocyanins from barberry were encapsulated by proposed coacervates as wall material. The encapsulated extract had elevated thermal stability and showed a lower degradation rate.


Assuntos
Antocianinas/química , Composição de Medicamentos/métodos , Rosaceae/química , Brassicaceae , Coloides/química , Liofilização , Gelatina/química , Goma Arábica/química , Polissacarídeos/química , Sementes/química
6.
Int J Biol Macromol ; 148: 31-40, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31945432

RESUMO

The complexation mechanism of zedo gum and cress seed gum as nutraceutical polysaccharides with gelatin (type-A and type-B) was investigated as a function of pH, Protein to polysaccharide mixing ratio and ionic strength. Turbidity measurements were performed to achieve optimum reaction conditions. Furthermore, Zeta potential measurements along with measuring complex coacervation yield were carried out to support the turbidity results. The state diagrams representing complex coacervation formation limits were obtained for each system. FTIR analysis was performed on resulted complex coacervates which confirmed the molecular interactions between each gum and gelatin. Also, the coacervate phase of the suspensions showed shear-thinning behavior according to steady-state flows and represented higher values of storage moduli at lower frequencies in frequency sweep measurements. All systems which are assessed in this study have the potential to form particles, however, the one containing gelatin type-A had better performance in terms of pH stability.


Assuntos
Brassicaceae/química , Gelatina/química , Exsudatos de Plantas/química , Gomas Vegetais/química , Polissacarídeos/química , Prunus avium/química , Biopolímeros/química , Concentração de Íons de Hidrogênio , Nefelometria e Turbidimetria , Concentração Osmolar , Reologia , Sementes/química , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117554, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31753652

RESUMO

To prepare a novel highly photo-stable fluorescent chemosensor, curcumin was successfully immobilized to polyamidoamine dendrimer of zero (S1), first (S2) and second (S3) generations conjugated-UV absorber moieties. Chemical structure of synthesized chemosensors were well-analysed by FTIR, 1H-NMR, 13CNMR, elemental analysis, DSC and UV-vis techniques. Photo-physical characteristics and solvatochromism effect of three novel chemosensors in organic solvents with different dielectric constants ranged 2.21-37.78 were studied. The pH determination ability of S1, S2 and S3 in the range of 2-12 were also examined. Newly synthesized materials were employed for detection of different metal cations including Ag+, Ba2+, Cu2+, Ca2+, Cd2+, Fe3+, Hg2+, Ni2+, Pb2+ and Zn2+ and their possibility to apply as a cation chemosensor were evaluated. The results showed significant changes in their fluorescence intensity upon the different pHs and cations indicating their possibility to apply as a pH and metal cation chemosensor. Among the new chemosensors under study, S1 represented high sensitivity to pH in the range of 4-8 and high selectivity for Cu2+ over the other cations.

8.
3 Biotech ; 9(12): 456, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31832303

RESUMO

Ag/Cu2O/ZnO nanoparticles (NPs) were synthesized in situ on wool yarns. The wool yarns were subsequently dyed with the roots and stems of berberis vulgaris. The antibacterial, antioxidant, and dyeing properties of the treated wool yarns were studied. Scanning electron microscopy (SEM), differential scanning calorimeters (DSC), and weight gain (%) analyses were employed for the characterization of the treated samples. The results indicated that the highest color strength (K/S) was obtained at a dye concentration of 50% over the weight of fiber (o.w.f.), temperature 100 °C, time 60 min, and pH 5. Moreover, the antioxidant and antimicrobial activities of the treated samples with NPs, and dyed with roots and stems of berberis vulgaris were excellent (about 100%). The treated samples with Ag NPs and dyed with the natural dyes showed very high antimicrobial activity (> 84%) after 10 repeated washing cycles. Finally, the colorfastness properties of the dyed and treated wool samples against washing and light irradiation were studied. It was concluded that the roots and stems of berberis vulgaris could be considered as suitable natural colorants for dyeing of wool yarns with acceptable colorfastness properties, excellent antimicrobial and antioxidant activities.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 154: 207-214, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26529637

RESUMO

In this study, 4-amino-1,8-naphthalimide-conjugated polyamidoamine dendrimer was synthesized and characterized and its potentiality as a cation sensor was investigated. 4-Amino-1,8-naphthalic anhydride reacted with polyamidoamine dendrimer and the product was characterized using FTIR, (1)H NMR, (13)C NMR and melting point analysis method. The synthesized compound was applied to detect various cations in water media and N,N-dimethylformamide (DMF) via monitoring the quenching of the fluorescence intensity. Furthermore, various metal cations including Cu(2+), Ni(2+), Zn(2+), Pb(2+),Ca(2+), Ba(2+), Cd(2+), Hg(2+), Fe(2+), Fe(3+) and Ag(+) were tested. The complexes formed between the synthesized compound and metal cations in solution and their effects on Photoinduced Electron Transfer (PET) process were investigated regarding the potential application of the newly-synthesized dendrimer as a colorimetric and fluorescent sensor for such cations. The results clearly confirmed that the 1,8-naphthalimide groups surrounding the central dendrimer core showed strong green fluorescence emission at 553 nm. This effect considerably decreased with the introduction of all cations, except Ag(+) where the fluorescence quenching effect was remarkable and more dominant. Therefore, it can be concluded that the synthesized dye has the potentiality of being a highly sensitive and selective fluorescence sensor for Ag(+) cation.


Assuntos
1-Naftilamina/análogos & derivados , Dendrímeros/química , Corantes Fluorescentes/química , Naftalimidas/química , Poliaminas/química , Quinolonas/química , Prata/análise , 1-Naftilamina/química , Cátions Monovalentes/análise , Espectroscopia de Ressonância Magnética , Espectrometria de Fluorescência/métodos , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Biotechnol Prog ; 31(4): 1086-95, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25967675

RESUMO

A series of novel disperse dyes containing azo group were synthesized through a diazotization and coupling process. The 4-amino-N-2-aminomethylpyridine-1,8-naphthalimide was diazotized by nitrosylsulphuric acid and coupled with various aromatic amines such as N,N-diethylaniline, N,N-dihydroxyethylaniline, 8-hydroxyquinoline, and 2-methylindole. Chemical structures of the synthesized dyes were characterized by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), proton nuclear magnetic resonance ((1) H NMR), carbon nuclear magnetic resonance ((13) C NMR), elemental analysis, and ultraviolet-visible (UV-visible) spectroscopy. The spectrophotometric data of all dyes were evaluated in various solvents with different polarity. Eventually, the dyes were applied on polyamide fabrics in order to investigate their dyeing properties. The fastness properties of the dyed fabrics such as wash, light, and rubbing fastness degrees were measured by standard methods. Moreover, the color gamut of the synthesized dyes was measured on polyamide fabrics. Results indicated that some of the synthesized dyes were able to dye polyamide fabrics with deep shades. They had very good wash and rubbing fastness degrees and moderate-to-good light fastness on polyamide fabrics. The antibacterial and antifungal activities of the synthesized dyes were evaluated in soluble state and on the dyed fabrics. The results indicated that dye 2 containing N,N-dihydroxyethylaniline as coupler had the highest activity against all the bacteria and fungi used.


Assuntos
Antibacterianos/química , Compostos Azo/química , Corantes/química , Naftalimidas/química , Antibacterianos/farmacologia , Compostos Azo/farmacologia , Bactérias/efeitos dos fármacos , Corantes/farmacologia , Testes de Sensibilidade Microbiana , Naftalimidas/farmacologia , Espectrofotometria , Têxteis
11.
Food Chem ; 141(1): 117-23, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23768336

RESUMO

In this study, the optimised ß-carotene loaded nanostructured lipid carriers (NLC) were prepared using the solvent diffusion method. Response surface methodology (RSM) was employed in conjunction with a central composite design (CCD) to evaluate the effect of the preparation variables on particle size and ß-carotene stability to optimise the NLC formulation. Quadratic polynomial was the best fitted mathematical model for the experimental results. The statistical evaluations revealed that the lipid phase concentration and the surfactant concentration had significant effect on particle size of NLC. In addition, the influence of the liquid lipid to total lipid ratio and temperature on ß-carotene degradation was more important. The optimum formulations with minimum particle size (8-15 nm) and low ß-carotene degradation (0-3%) were derived from the fitted models and were experimentally examined which demonstrated a reasonable agreement between experimental and predicted values. Transition electron microscopy (TEM) observations exhibited spherical morphology of ß-carotene loaded NLC.


Assuntos
Química Farmacêutica/métodos , Portadores de Fármacos/química , Lipídeos/química , Nanoestruturas/química , beta Caroteno/química , Difusão , Estabilidade de Medicamentos , Tamanho da Partícula
12.
Artigo em Inglês | MEDLINE | ID: mdl-22446761

RESUMO

In this paper, preparation and visible light induced photocatalytic activity of phthalocyanine-modified Fe-doped TiO(2) nanocrystals (Pc/Fe-TiO(2)) with different Fe doping content (0, 0.05, 0.5 and 3.0 mol% Fe) as photocatalysts for the degradation of methyl orange have been reported. The study carried out using XRD, FT-IR, EDX, BET, DRS, UV-Vis, SEM and TEM techniques. Results revealed that modified TiO(2) nanocrystals possessed only the anatase phase with crystal sizes of about 10-23 nm and high surface areas of 2.8-37.3 m(2)/g. It can be seen phthalocyanine and Fe(3+) ion exist in photocatalysts based on analysis of FT-IR and EDX. The doping amount of Fe remarkably affects the activity of modified TiO(2) nanocrystals as catalysts. The 0.5 mol% Fe doping exhibited enhanced photocatalytic activity in this work. It was found that phthalocyanine and Fe induced a shift in the energy band gap to lower energies, which changes from 3.26 to 2.26 eV for pure TiO(2) and Pc/3% Fe-TiO(2) nanocrystals, respectively. Results of the degradation of methyl orange revealed that modified TiO(2) nanocrystals showed much more photocatalytic activity than pure TiO(2) under visible light which makes the applicability of TiO(2) photocatalysts even more versatile.


Assuntos
Compostos Azo/química , Indóis/química , Ferro/química , Nanopartículas/química , Fotólise , Titânio/química , Catálise , Isoindóis , Luz , Modelos Moleculares , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Artigo em Inglês | MEDLINE | ID: mdl-22321515

RESUMO

A novel N-allyl-4-amino-substituted 1,8-naphthalimide dye, containing thiourea functional group with intense yellow-green fluorescence was successfully synthesized. Copolymerization was done with styrene. The photophysical characteristics of dye and its copolymer in solution and solid film were investigated in the presence of halide ions. The results reveal that the fluorescence emissions of the monomer dye and also its polymer were 'switched off' in the presence of fluoride ions. The dye showed spectral shifts and intensity changes in the presence of more fluoride ions which lead to detect certain fluoride concentrations of 10-150 mM at visible wavelengths. By adding the fluoride ions, green-yellow to purple color changes occurs and the green fluorescence emission quenches, all of which easily observed by naked eyes. These phenomena are essential for producing a dual responsive chemosensor for fluoride ions. The polymeric sensor, in the film state exhibited a fast response to the fluoride ions.


Assuntos
1-Naftilamina/análogos & derivados , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Fluoretos/química , Naftalimidas/química , Quinolonas/química , Tioureia/química , 1-Naftilamina/química , Fluorescência , Estrutura Molecular , Fotoquímica , Polimerização
14.
J Hazard Mater ; 145(1-2): 65-71, 2007 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-17145132

RESUMO

Degradation and mineralization of two agricultural organic pollutants (Diazinon and Imidacloprid as N-heterocyclic aromatics) in aqueous solution by nanophotocatalysis using immobilized titania nanoparticles were investigated. Insecticides, Diazinon and Imidacloprid, are persistent pollutants in agricultural soil and watercourses. A simple and effective method was developed to immobilization of titania nanoparticles. UV-vis, ion chromatography (IC) and chemical oxygen demand (COD) analyses were employed. The effects of operational parameters such as H(2)O(2) and inorganic anions (NO(3)(-), Cl(-) and SO(4)(2-)) were investigated. The mineralization of Diazinon and Imidacloprid was evaluated by monitoring of the formed inorganic anions. The selected pollutants are effectively degraded following first order kinetics model. Results show that the nanophotocatalysis using immobilized titania nanoparticle is an effective method for treatment Diazinon and Imidacloprid from contaminated water.


Assuntos
Azirinas/química , Di-Hidropiridinas/química , Imidazóis/química , Nanopartículas Metálicas/química , Nitrocompostos/química , Titânio/química , Poluentes Químicos da Água/química , Purificação da Água , Agroquímicos , Catálise , Neonicotinoides , Fotoquímica , Raios Ultravioleta , Purificação da Água/instrumentação , Purificação da Água/métodos
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