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Dye-contaminated wastewater discharge from textile and dye manufacturing industries is reported as a world worse water polluter due to the toxic and mutagenic behavior of dyes. Peroxidase, one of the key enzymes of oxidoreductases, is widely distributed in nature and has been currently exploited in industries for various applications. Widespread applications of peroxidases are associated with their nonspecific nature towards a wide spectrum of substrates such as phenols, aromatic amines, pesticides, antibiotics, and synthetic dyes. The present study explored the potential of ammonium sulfate precipitated partially purified Brassica oleracea L. var. botrytis leaves peroxidase for degradation of reactive textile dyes Remazol Turquoise Blue 133 G and Drim Red CL4BN. Various physico-chemical parameters such as pH (2-9), temperature (20-70 â), enzyme activity (3-24 U/mL), concentrations of H2O2 (0.4-1.4 Mm) and dye (10-100 mg/L) were optimized for enzymatic decolorization of both dyes' solution. Studies revealed that maximum degradation (95%) of Remazol Turquoise Blue 133 G with peroxidase was achieved with 25 mg/L of initial dye concentration, in the presence of 0.8 mM hydrogen peroxide with 45 min of incubation time, at pH 3, 4, and 5, and 70 °C. Maximal decolorization (97%) of Drim Red CL4BN was obtained at pH 2.0, in 10 min of incubation time at 45 â using o-dianisidine hydrochloride as a redox mediator. In conclusion, the findings illustrate the prospect of Brassica oleracea peroxidase to remediate dye pollutants and dye-based industrial effluents in a green technology theme.
Assuntos
Brassica , Peroxidase , Botrytis/metabolismo , Peróxido de Hidrogênio , Peroxidases/metabolismo , Corantes/metabolismo , Indústria Têxtil , Têxteis , Folhas de Planta/metabolismo , Biodegradação AmbientalRESUMO
One of the big environmental problems in today's world is dye-contaminated toxic waste. Peroxidase is known as highly efficient for the degradation of various pollutants, including dyes. Environmental contamination caused by the discharge of dyes into water bodies is an onerous challenge that poses both human and ecological hazards. In the current studies, biocatalysts used for enzyme decolorization (1847 Colafx Blue P3R and 621 Colafx Blue) are regarded as an eco-friendly method utilizing commonly available low-cost material lemon peels (Citrus limon peroxidase). Peroxidase was extracted in a phosphate buffer of pH 7.0 and partially purified by 20-80% ammonium sulfate precipitation technique from Citrus limon peels. The soluble enzyme was characterized in terms of kinetic and thermodynamic parameters. The values of Km and Vmax (23.16 and 204.08 µmol/ml/min) were determined, respectively. The enzyme showed maximum activity at pH 5.0 and a temperature of 55 °C. Citrus limon efficiently degraded 1847 Colafx Blue P3R and 621 Colafx Blue R dyes with maximum degradation of 83 and 99%, respectively, with an initial dye concentration of 200 ppm at pH 4 and 35 °C temperature within 5-10 min of incubation time. The effect of the redox mediator on the degradation process was examined. Results showed that the peroxidase HOBT system efficiently enhanced the degradation of dyes from water. Hence, Citrus limon peroxidase is an efficient biocatalyst for the treatment of effluents.
Assuntos
Citrus , Corantes , Peroxidase , Poluentes Químicos da Água , Biodegradação Ambiental , Corantes/química , Peroxidases/química , Poluentes Químicos da Água/químicaRESUMO
Microbial lipases hold a prominent position in biocatalysis by their capability to mediate reactions in aqueous and nonaqueous media. Herein, a lipase from Penicillium fellutanum was biochemically characterized and investigated its potential to degrade poly (É-caprolactone) (PCL). The lipase exhibited stability over a broad pH spectrum and performed best at pH 8.5 and 45 °C. The activation energy was determined to be 66.37 kJ/mol by Arrhenius plot, whereas Km and Vmax for pNPP hydrolysis were 0.75 mM and 83.33 µmol/mL/Min, respectively. A rise in temperature reduced the Gibbs free energy, whereas the enthalpy of thermal unfolding (∆H*) remains the same up to 54 °C following a modest decline at 61 °C. The entropy (∆S*) of the enzyme demonstrated an increasing trend up to 54 °C and dropped at 61 °C. Lipase retained stability by incubation with various industrially relevant organic solvents (benzene, hexanol, ether, and acetone). However, exposure to urea and guanidine hydrochloride influenced its catalytic activity to different extents. Under optimal operating conditions, lipase catalyzed the excellent degradation of PCL film degradation leading to 66% weight loss, increased surface erosion, and crystallinity. Fourier-transform infrared spectrometry, differential scanning calorimetry, and scanning electron microscopy studies monitored the weight loss after enzymatic hydrolysis. The findings indicate that P. fellutanum lipase would be a prospective biocatalytic system for polyesters depolymerization and environmental remediation.
Assuntos
Lipase , Poliésteres , Caproatos , Humanos , Lactonas , Lipase/química , Penicillium , Poliésteres/metabolismo , Estudos Prospectivos , Termodinâmica , Redução de PesoRESUMO
Three benzimidazolium salts (III-V) and respective selenium adducts (VI-VIII) were designed, synthesized and characterized by various analytical techniques (FT-IR and NMR 1H, 13C). Selected salts and respective selenium N-Heterocyclic carbenes (selenium-NHC) adducts were tested in vitro against Cervical Cancer Cell line (Hela), Breast Adenocarcinoma cell line (MCF-7), Retinal Ganglion Cell line (RGC-5) and Mouse Melanoma Cell line (B16F10) using MTT assay and the results were compared with standard drug 5-Fluorouracil. Se-NHC compounds and azolium salts showed significant anticancer potential. Molecular docking studies of compounds (VI, VII and VIII) showed strong binding energies and ligand affinity toward following angiogenic factors: VEGF-A (vascular endothelial growth factor A), EGF (human epidermal growth factor), HIF (Hypoxia-inducible factor) and COX-1 (Cyclooxygenase-1) suggesting that the anticancer activity of adducts (VI, VII and VIII) may be due to their strong anti-angiogenic effect. In addition, compounds III-VIII were screened for their antibacterial and antifungal potential. Adduct VI was found to be potent anti-fungal agent against A. Niger with zone of inhibition (ZI) value 27.01⯱â¯0.251 mm which is better than standard drug Clotrimazole tested in parallel.
Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Compostos Organosselênicos/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/metabolismo , Antifúngicos/síntese química , Antifúngicos/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Aspergillus niger/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Benzimidazóis/síntese química , Benzimidazóis/metabolismo , Linhagem Celular Tumoral , Ciclo-Oxigenase 1/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Fator de Crescimento Epidérmico/metabolismo , Escherichia coli/efeitos dos fármacos , Química Verde , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Compostos Organosselênicos/síntese química , Compostos Organosselênicos/metabolismo , Ligação Proteica , Carneiro Doméstico , Staphylococcus aureus/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The aim of the present study was to enhance the pharmaceutical potential and oral bioavailability of piperine, which is the bioactive constituent of Piper nigrum, using the nanosuspension approach. Nanoprecipitation, which is a simple and reproducible process, was used for nanosuspension formulation. To prepare a pharmaceutical-grade nanosuspension with the required particle size, important formulation parameters (amount of plant extract, concentration of stabilizer, and antisolvent-to-solvent ratio) were optimized using the central composite design of response surface methodology. The optimized nanosuspension was characterized using scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, and in vitro dissolution testing as well as by measuring the zeta potential. In vivo pharmacokinetic studies were conducted to determine the bioavailability of the prepared nanosuspension. Results of the optimization study indicated that 0.13% plant extract, 0.25% stabilizer, and an antisolvent-to-solvent ratio of 10.0 were the best parameters to obtain a homogeneous nanosuspension with the required particle size. The optimized nanosuspension demonstrated a mean particle size, polydispersity index, and zeta potential of 172.5 nm, 0.241, and - 16.6 mV, respectively. The results of the characterization studies illustrated that the nanosuspension was in the nanometer size range and had good surface morphology. The optimized nanosuspension showed a better dissolution rate and a 3.65-fold higher oral bioavailability for the P. nigrum nanosuspension than its coarse suspension. The present outcomes clearly demonstrated that to obtain an effective therapeutic potential, nanoformulation of medicinal plants is a better alternative than conventional dosage forms.
Assuntos
Alcaloides/isolamento & purificação , Benzodioxóis/isolamento & purificação , Piper nigrum/química , Piperidinas/isolamento & purificação , Alcamidas Poli-Insaturadas/isolamento & purificação , Administração Oral , Alcaloides/administração & dosagem , Alcaloides/farmacocinética , Animais , Benzodioxóis/administração & dosagem , Benzodioxóis/farmacocinética , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos , Masculino , Microscopia Eletrônica de Varredura , Nanopartículas/ultraestrutura , Tamanho da Partícula , Piperidinas/administração & dosagem , Piperidinas/farmacocinética , Alcamidas Poli-Insaturadas/administração & dosagem , Alcamidas Poli-Insaturadas/farmacocinética , Ratos , Ratos WistarRESUMO
In the present study, Pleurotus ostreatus IBL-02, a white rot basidiomycete was exploited for lipase production in solid-state fermentation (SSF). Different agro-industrial wastes such as canola-oilseed cake, cotton-oilseed cake, linseed-oil cake, sesame-oilseed cake, rice bran and wheat bran were screened for fermentative production of the lipolytic enzyme. The enzyme profile of P. ostreatus showed the highest activity of lipase on canola oil seed cake as a substrate under SSF conditions. Various physiological factors such as incubation time, humidity level, culture pH, incubation temperature and supplementation of carbon and nitrogen sources were optimized to induce the lipase synthesis capability of P. ostreatus at an optimal level. Optimum lipase activity (3256 U/gram dry substrate) was measured in the solid fermentation medium using moisture level, 50.0%; pH, 4.0; temperature, 30°C and olive oil, 2.0% after 72 h of incubation period with glucose and urea as carbon and nitrogen supplements, respectively. Glucose supplementation significantly stimulated the lipase production, while nitrogen addition did not exert any significant effect on lipase yield. Overall, under optimized bioprocess conditions, the enzyme activity was improved up to 1.6 folds with respect to the original enzyme activities. The current findings indicate that culture conditions have great influence on the lipase production potential of P. ostreatus for commercial purpose.
Assuntos
Meios de Cultura/química , Lipase/biossíntese , Pleurotus/metabolismo , Biotecnologia/métodos , Carbono/metabolismo , Fibras na Dieta , Fermentação , Indústria de Processamento de Alimentos , Concentração de Íons de Hidrogênio , Resíduos Industriais , Nitrogênio/metabolismo , Azeite de Oliva , Temperatura , Fatores de TempoRESUMO
Native, HCl pretreated clay and MnFe2O4/clay composite were investigated as an adsorbent for crystal violet (CV) removal. The adsorption behavior of dye was studied in batch experiments as a function of contact time, adsorbent dose, pH, dye initial concentration and temperature. The medium pH 8, contact time 30 min, MnFe2O4/clay composite dose 0.05 mg/L, temperature 35 °C and 100 mg/L dye initial concentration furnished maximum CV adsorption. Adsorption data fitted well to the Langmuir isotherm model and maximum CV dye adsorption capacity of composite was 49.74 mg/g. The thermodynamic parameters revealed that the adsorption process of CV was exothermic and spontaneous in nature. CV adsorption followed the pseudo second order kinetic model. MnFe2O4/clay composite exhibited good CV adsorption capacity and can be used as an alternative adsorbent for the removal of basic dyes from effluents.
Assuntos
Silicatos de Alumínio/química , Compostos Férricos/química , Violeta Genciana/isolamento & purificação , Compostos de Manganês/química , Modelos Químicos , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Argila , TermodinâmicaRESUMO
Environmental applications of composites have attracted the interests of researchers due to their excellent adsorption efficiency for pollutants. Native, HCl pre-treated clay and MnFe2O4/clay composite were investigated as an adsorbent for removal of methyl green from aqueous solution. The adsorption behaviors of dye onto native, HCl pre-treated and composite clays were studied as a function of contact time, adsorbent dose, pH, initial dye concentration and temperature. Maximum dye adsorption of 44 mg/g was achieved at pH of 8, contact time 40 min, adsorbent dose 0.20 g/L and initial dye concentration of 125 mg/L using clay composite. The Langmuir isotherm and pseudo-second-order kinetic model best explained the methyl green dye adsorption onto clay adsorbents. Thermodynamic parameters revealed the endothermic and spontaneous adsorption nature of dye. From results, it is concluded that clay has potential for adsorbing methyl green and can be used for the removal of dyes from industrial effluents.
Assuntos
Silicatos de Alumínio/química , Corantes/análise , Modelos Teóricos , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Cátions Bivalentes , Argila , Corantes/química , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica , Poluentes Químicos da Água/químicaRESUMO
Batch and column adsorption modes were compared for the adsorption of U(VI) ions using rice husk waste biomass (RHWB). Response surface methodology was employed for the optimization of process variables, i.e., (pH (A), adsorbent dose (B), initial ion concentration (C)) in batch mode. The B, C and C2 affected the U(VI) adsorption significantly in batch mode. The developed quadratic model was found to be validated on the basis of regression coefficient as well as analysis of variance. The predicted and actual values were found to be correlated well, with negligible residual value, and B, C and C2 were significant terms. The column study was performed considering bed height, flow rate and initial metal ion concentration, and adsorption efficiency was evaluated through breakthrough curves and bed depth service time and Thomas models. Adsorption was found to be dependent on bed height and initial U(VI) ion concentration, and flow rate decreased the adsorption capacity. Thomas models fitted well to the U(VI) adsorption onto RHWB. Results revealed that RHWB has potential to remove U(VI) ions and batch adsorption was found to be efficient versus column mode.
Assuntos
Oryza , Urânio/química , Poluentes Radioativos da Água/química , Purificação da Água/métodos , Adsorção , Biomassa , Concentração de Íons de Hidrogênio , Resíduos RadioativosRESUMO
Adsorption techniques are widely used to remove pollutants from wastewater; however, composites are gaining more importance due to their excellent adsorption properties. Bentonite composite with Eriobotrya japonica seed was prepared and used for the adsorption of copper (Cu) metal from aqueous media. The process variables such as pH, Cu(II) ions initial concentration, adsorbent dose, contact time and temperature were optimized for maximum Cu(II) adsorption. At pH 5, adsorbent dose 0.1 g, contact time 45 min, Cu(II) ions initial concentration 75 mg/L and temperature 45 °C, maximum Cu(II) adsorption was achieved. Desorption studies revealed that biocomposite is recyclable. Langmuir, Freundlich and Harkins-Jura isotherms as well as pseudo-first and pseudo-second-order kinetics models were applied to understand the adsorption mechanism. Thermodynamic parameters (ΔG(0), ΔH(0) and ΔS(0)) suggest that the adsorption process was spontaneous and endothermic in nature. The pseudo-second-order kinetic model and Langmuir isotherm fitted well to the adsorption data. Results showed that biocomposite was more efficient for Cu(II) adsorption in comparison to individuals native Eriobotrya japonica seed biomass and Na-bentonite.
Assuntos
Cobre/química , Eriobotrya/química , Sementes/química , Termodinâmica , Adsorção , Bentonita/química , Concentração de Íons de Hidrogênio , Modelos Teóricos , Temperatura , Poluentes Químicos da Água/análise , Purificação da ÁguaRESUMO
Enzyme assisted solvent extraction (EASE) of phenolic compounds from watermelon (C. lanatus) rind (WMR) was optimized using Response Surface Methodology (RSM) with Rotatable Central Composite Design (RCCD). Four variables each at five levels i.e. enzyme concentration (EC) 0.5-6.5 %, pH 6-9, temperature (T) 25-75 °C and treatment time (t) 30-90 min, were augmented to get optimal yield of polyphenols with maximum retained antioxidant potential. The polyphenol extracts obtained under optimum conditions were evaluated for their in-vitro antioxidant activities and characterized for individual phenolic profile by RP-HPLC-DAD. The results obtained indicated that optimized EASE enhanced the liberation of antioxidant phenolics up to 3 folds on fresh weight basis (FW) as compared to conventional solvent extraction (CSE), with substantial level of total phenolics (173.70 mg GAE/g FW), TEAC 279.96 mg TE/g FW and DPPH radical scavenging ability (IC50) 112.27 mg/mL. Chlorogenic acid (115.60-1611.04), Vanillic acid (26.13-2317.01) and Sinapic acid (113.01-241.12 µg/g) were major phenolic acid found in EASEx of WMR. Overall, it was concluded that EASE might be efficient and green technique to revalorize under-utilized WMR into potent antioxidant phenolic for their further application in food and nutraceutical industries.
RESUMO
Sound velocity, U, and density, ρ of some amino acids viz. glycine, methionine, phenylalanine and tryptophan were determined in 0.1, 0.2 and 0.3 mol kg⻹ aqueous disodium citrate solutions as a function of concentration at 298-313.15K using DSA 5000M. The experimental data were further used to compute various acoustical parameters such as adiabatic compressibility, ß, apparent molar compressibility, ∅(k), partial molar compressibility, ∅(0)k, transfer adiabatic compressibility, Φ(0)(ktr), constant, Sk, and the hydration number, nH. The transfer adiabatic compressibility shows the supremacy of hydrophilic-ionic interactions under hydrophobic-ionic interactions. The above-mentioned parameters are relevant for the efficiency of mediation in pharmacology and can be interpreted in terms of structure-making or structure-breaking ability of these amino acids in the solution.
Assuntos
Aminoácidos/química , Soluções , Temperatura , TermodinâmicaRESUMO
An efficient biosorbent, sugarcane bagasse was used in native, HCl-treated, and Na-alginate immobilized form for the removal of Direct Violet 51 dye from aqueous solutions. Batch study was performed to optimize important process parameters, such as pH, contact time, biosorbent dose, initial dye concentration, and temperature. Removal of Direct Violet 51 was found to be favorable at pH 2 with the biosorbent dose of 0.05 g. Biosorption process was found to be exothermic in nature. Maximum dye biosorption (39.6 mg/g) was achieved by using HCl-treated biomass. The pseudo-second-order kinetic and Langmuir adsorption isotherm models showed best fitness to the experimental data. Thermodynamic study was also performed to determine the feasibility of biosorption process. Continuous mode study was performed to optimize the important process parameters, such as bed height, flow rate, and initial dye concentration for maximum removal of Direct Violet 51 dye. The higher bed height, low flow rate, and high initial dye concentration were found to be the better conditions for maximum dye biosorption (17.28 mg/g). The linearized form of the Thomas model equation fitted well to the experimental data. The bed depth service time model was used to express the effect of bed height on breakthrough curves. Characterization of biosorbent was performed by scanning electron microscopy and Fourier transform infrared (FT-IR) analysis. The FT-IR spectral analyses showed the involvement of hydroxyl, carbonyl, and carboxyl groups in biosorption process. These results indicated that sugarcane bagasse biomass could be used as a novel biosorbent for the removal of Direct Violet 51 dye from real textile and related industries.
Assuntos
Compostos Azo/química , Naftalenossulfonatos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Adsorção , Alginatos/química , Compostos Azo/análise , Celulose/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Cinética , Modelos Químicos , Naftalenossulfonatos/análise , Poluentes Químicos da Água/análiseRESUMO
During the past few years, research has focused on the microbial transformation of a huge variety of organic compounds to obtain compounds of therapeutic and/or industrial interest. Microbial transformation is a useful tool for organic chemists looking for new compounds, as a consequence of the variety of reactions for natural products. Terpenoids are a large family of natural products exhibiting a wide range of biological activities such as antibiotics, anti-inflammatory, anti-HIV and anti-tumor effects; hypotensive agents; sweeteners; insecticides; anti-feedants; phytotoxic agents; perfumery intermediates; and plant growth hormones. This article describes the biotransformation products of diterpenoids and triterpenoids in a variety of biological media. Emphasis is placed on reporting the metabolites that may be of special interest as well as the practical aspects of this work in the field of microbial transformations. This review covers the literature from 1991 to 2012.
Assuntos
Anti-Inflamatórios/metabolismo , Produtos Biológicos/metabolismo , Diterpenos/metabolismo , Triterpenos/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Biotransformação , Diterpenos/química , Diterpenos/farmacologia , Triterpenos/química , Triterpenos/farmacologiaRESUMO
The optimum conditions to label ethylenediaminetetramethylene phosphonate (EDTMP) compound with (90)y as a potential candidate for bone metastases therapy were investigated. Yttrium-90 is a pure ß-emitter and can be obtained by (89)y (n,γ) (90)y nuclear reaction in a reactor or from an in-house generator system ((90)srï®(90)y). The preparation of (90)Y-EDTMPis described using (90)y, which was obtained from neutron irradiation of y2o3 as well as from a laboratory scale organic resin-based (90)sr--(90)y generator. Because of the radiolabeling yield of 90Y-EDTMP on ligand/metal molar ratio, incubation time and ph was evaluated. Under optimum parameters, the radiolabeling yields of (90)Y-EDTMP were <95% for no-carrier-added as well as carrier-added (90)y. The biodistribution of no-carrier-added and carrier-added (90)Y-EDTMP complexes in rats was identical. The results indicate that (90)y (carrier-added)-edtmp is also an effective bone pain palliation agent because of its rapid blood clearance, greater uptake in bones and little absorption in soft tissues.
Assuntos
Neoplasias Ósseas/radioterapia , Compostos Organofosforados/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Radioisótopos de Ítrio/uso terapêutico , Animais , Neoplasias Ósseas/secundário , Portadores de Fármacos , Marcação por Isótopo , Masculino , Compostos Radiofarmacêuticos/farmacocinética , Ratos , Ratos Sprague-Dawley , Distribuição TecidualRESUMO
Photocatalysis is a clean and efficient process pursued under light irradiation with a suitable photocatalyst to degrade a contaminant. We report citrate functionalization of silver nanoparticles (SNPs) for effective immobilization on cellulosic fabric. The porous cellulosic matrix could be explored as microfiltration membranes for the photocatalytic degradation of organic dyes in the aqueous media. Where valid, the citrate functionalized SNPs and the treated cellulose fabrics were considered for optical, structural, surface chemical, thermal, textile, flowability, photocatalytic, and antibacterial attributes. The SNPs expressed the bandgap energy of 2.56 and 2.43 eV and Urbach energy of 3.38 and 5.21 eV before and after functionalization with the citrate moieties, respectively. The liquid chromatographic and FTIR analyses indicated that the crystal violet (CV) organic dye has been successfully photodegraded to environmentally safer and nontoxic species on passing the contaminated water through the SNPs-treated cellulosic filter. The spectroscopic data also supported the said outcomes. The results demonstrated that the citrate-SNPs-treated cellulose could be efficiently employed as antibacterial photocatalytic membranes for degrading organic dyes in the aqueous media for multiple cycles.
Assuntos
Ácido Cítrico , Nanopartículas Metálicas , Prata , Citratos , Antibacterianos/farmacologia , Celulose , CorantesRESUMO
In this study, nickel manganite (NiMn2O4) nanoparticles were prepared using a hydrothermal method and examined its potential as a photocatalyst for the Acid Green 25 (AG-25) dye degradation. The nanoparticles were subjected to structural analysis using X-ray diffraction (XRD) and morphological analysis using scanning electron microscopy (SEM). The study examined the kinetics and thermodynamics of degradation processes that are catalyzed by photocatalysis. To ascertain their effect on dye degradation, several parameters, such as catalyst dose, H2O2 concentration, and temperature, were investigated. With a temperature of 315 K in a pseudo-first-order kinetic reaction, a 0.3 M H2O2 concentration, 0.05 mg/mL catalyst dose, and a promising removal efficiency of 96 % was achieved by the NiMn2O4 NPs in 40 min. Thermodynamic analysis revealed the spontaneous and entropy-driven nature of catalytic degradation, progressing favorably at elevated temperatures. Additionally, the NiMn2O4 NPs were applied as a fuel additive to analyze its influence on combustion and the physical characteristics of the modified fuel. The modified fuel demonstrated exceptional catalytic efficiency, emphasizing the potential of the NiMn2O4 NPs as an effective additive.
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Improving the light-harvesting efficiency and boosting open circuit voltage are crucial challenges for enhancing the efficiency of organic solar cells. This work introduces seven new molecules (SA1-SA7) to upgrade the optoelectronic and photovoltaic properties of Q-C-F molecule-based solar cells. All recently designed molecules have the same alkyl-substituted Quinoxaline core and CPDT donor but vary in the end-capped acceptor subunits. All the investigated molecules have revealed superior properties than the model (R) by having absorbance ranging from 681 nm to 782 nm in the gaseous medium while 726 nm-861 nm in chloroform solvent, with the lowest band gap ranging from 1.91 to 2.19 eV SA1 molecule demonstrated the highest λmax (861 nm) in chloroform solvent and the lowest band gap (1.91 eV). SA2 molecule has manifested highest dipole moment (4.5089 D), lower exciton binding energy in gaseous (0.33 eV) and chloroform solvent (0.47 eV), and lower charge mobility of hole (0.0077693) and electron (0.0042470). At the same time, SA7 showed the highest open circuit voltage (1.56 eV) and fill factor (0.9166) due to solid electron-pulling acceptor moieties. From these supportive outcomes, it is inferred that our computationally investigated molecules may be promising candidates to be used in advanced versions of OSCs in the upcoming period.
Assuntos
Clorofórmio , Quinoxalinas , Elétrons , Gases , SolventesRESUMO
The purpose of this study was to synthesize ecofriendly nano-composite in which agricultural waste (seeds of Tamarindus indica) was used to synthesize tamarind seed polysaccharides (TSP) and its composite with copper nanoparticles (Cu-NPs) for the purpose of green and clean environment as well as reduction of green-house gases. Confirmation of extracted TSP, synthesized nanocomposite was carried out using FTIR, SEM, PXRD and EDX techniques. In FTIR analysis TSP gives a strong broad peak at 3331 cm-1 due to -OH group and in case of composite its intensity is reduced which might be due to the interactions between -OH and Cu+2 ions. SEM analysis gives that TSP have irregular and rough surface while Cu-NPs exhibited spherical morphology and composite showed clustering of spherical shape to rough surface. EDX analysis quantitatively represented copper having atomic ratio 0.57 % which confirms the synthesis of composite. Furthermore, synthesized composite demonstrated excellent antibacterial activity against gram-positive (S.aureus) and gram-negative bacteria (E.coli) even greater than standard medicine (ciprofloxacin). From this study it was revealed that agriculture waste can be utilized to make environment green as well as synthesized composite from agricultural waste seed also displayed excellent antimicrobial activities which directs that they can be utilized in medical field. This study aims to assess the antimicrobial properties of the nanocomposite, aiming to contribute to the development of effective antimicrobial agents. Through these objectives, the research seeks to bridge the gap between green technology and antimicrobial efficacy, offering a promising avenue for both environmental conservation and healthcare advancements.
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Background The prognosis for oral cancer patients is still very poor worldwide. Early detection and treatment therapy remain the key issue to be addressed for improved patient survival. The characteristic Raman spectral features associated with the biochemical changes in the blood serum samples can be used for the diagnosis of diseases, particularly for oral cancer. Surface-enhanced Raman spectroscopy (SERS) is a promising technique for non-invasive and early detection of oral cancer by analyzing molecular changes in body fluids. Objectives To detect oral cavity anatomical subsites (buccal mucosa, cheek, hard palate, lips, mandible, maxilla, tongue and tonsillar region) cancers by using blood serum samples, SERS with principal component analysis is used. Material and Method SERS is employed with silver nanoparticles for the analysis and detection of oral cancer serum samples by comparing with healthy serum samples. SERS spectra are recorded by Raman instrument and preprocessed using the statistical tool. Principal component analysis (PCA) and Partial least square discriminant analysis (PLS-DA) are used to discriminate between oral cancer serum samples and control serum samples. Results Some major SERS peaks are observed at 1136 cm-1 (Phospholipids) and 1006 cm-1 (Phenylalanine) remain higher in intensities for oral cancer spectra as compared to healthy spectra. The peak at 1241 cm-1 (amide III) is observed only in oral cancer serum samples while absent in healthy serum samples. Higher protein and DNA contents were detected in SERS mean spectra of oral cancer. Moreover, PCA is used to identify the biochemical differences in the form of SERS features which is used to differentiate between oral cancer and healthy blood serum samples, while PLS-DA is used to build differentiation model of oral cancer serum samples and healthy control serum samples. PLS-DA provides successful differentiation with 94% specificity and 95.5% sensitivity. Conclusions SERS can be used for the diagnosis of oral cancer and to identify metabolic changes that occur during disease development.