RESUMEN
Pesticides in environmental samples pose significant risks to ecosystems and human health since they require precise and efficient detection methods. Imidacloprid (IMI), a widely used neonicotinoid insecticide, exemplifies these hazards due to its potential toxicity. This study addresses the urgent need for improved monitoring of such contaminants by introducing a novel fluorometric method for detecting IMI using nitrogen-doped graphite carbon dots (N-GCDs). The sensor operates by quenching fluorescence through the interaction of Cu2+ ions with N-GCDs. Subsequently, IMI binds to the imidazole group, chelates with Cu2+, and restores the fluorescence of N-GCDs. This alternating fluorescence behavior allows for the accurate identification of both Cu2+ and IMI. The sensor exhibits linear detection ranges of 20-100 nM for Cu2+ and 10-140 µg/L for IMI, with detection limits of 18 nM and 1.2 µg/L, respectively. The high sensitivity of this sensor enables the detection of real-world samples, which underscores its potential for practical use in environmental monitoring and agricultural safety.
Asunto(s)
Cobre , Monitoreo del Ambiente , Fluorometría , Grafito , Neonicotinoides , Nitrocompuestos , Nitrógeno , Puntos Cuánticos , Neonicotinoides/análisis , Neonicotinoides/química , Nitrocompuestos/química , Nitrocompuestos/análisis , Cobre/química , Cobre/análisis , Nitrógeno/química , Grafito/química , Puntos Cuánticos/química , Insecticidas/análisis , Insecticidas/química , Imidazoles/químicaRESUMEN
In modern times, nanoparticles have materialized as indispensable things in contemporary medicine, with a variety of uses in clinical, drug and gene conveyance. In the present study, TiO2 nanoparticles (NPs) prepared from the leaf extracts of Mollugooppositifolia and Trianthema portulacastrum were compared with the chemical TiO2-NPs for antibacterial and antioxidant activities and environment-friendly nature through various tools like the UV-visible, X-ray diffraction with the aid of other analytical techniques like HR-TEM, Fourier transform infrared (FT-IR) and photoluminescence spectroscopic techniques. The morphology of green TiO2-NPs is found to be spherical, which is supported by HR-TEM images. FT-IR analyses and X-ray diffraction data ensure that the polycrystalline characters of TiO2-NPs alike to the presence of metal oxide. TiO2-NPs showed a possible photocatalytic activity for the ruin of acid black 1 dye after disclosure to sunlight. The chemical and green methods of TiO2-NPs have acid black 1 dye decomposition rates of 86.66% and 94.33%, respectively. The synthesized TiO2-NPs are also assessed for antimicrobial and antioxidant activities. Green TiO2-NPs exhibit antibacterial activity against Pseudomonas aeruginosa (17 + 0.56 mm) and Staphylococcus aureus (16 + 0.24 mm) at concentrations as low as 100 µL. The green TiO2-NPs showed high inhibition of DPPH I radical (50 µg/m) at 95.17 ± 21. Therefore, TiO2-NPs represent eco-friendly properties that aid in the degradation of dyes due to their antioxidant activity.
Asunto(s)
Antibacterianos , Antioxidantes , Titanio , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/síntesis química , Titanio/química , Titanio/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Nanopartículas/química , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/farmacología , Colorantes/química , Colorantes/farmacología , Luminiscencia , Staphylococcus aureus/efectos de los fármacos , Tamaño de la Partícula , Hojas de la Planta/química , Compuestos de Bifenilo/antagonistas & inhibidores , Compuestos de Bifenilo/químicaRESUMEN
Antibiotic residues persist in the environment and represent serious health hazards; thus, it is important to develop sensitive and effective detection techniques. This paper presents a bio-inspired way to make water-soluble fluorescent polymer carbon dots (PCDs@PVA) by heating biomass precursors and polyvinyl alcohol (PVA) together. For example, the synthesized PCDs@PVA are very stable with enhanced emission intensity. This property was observed in a wide range of environmental conditions, including those with changing temperatures, pH levels, UV light, and ionic strength. PCDs@PVA detected the antibiotic chlortetracycline (CTCs) with great selectivity against structurally related compounds and a low detection limit of 20 nM, demonstrating outstanding sensitivity and specificity. We confirmed the sensor's practical application through real sample analysis, yielding recovery rates of 98%-99% in samples of milk, honey, and river water. The synthesized PCDs@PVA fluorescence sensor was successfully used for CTCs detection in real samples.
Asunto(s)
Carbono , Clortetraciclina , Colorantes Fluorescentes , Alcohol Polivinílico , Puntos Cuánticos , Clortetraciclina/análisis , Alcohol Polivinílico/química , Carbono/química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Puntos Cuánticos/química , Animales , Leche/química , Antibacterianos/análisis , Antibacterianos/química , Antibacterianos/síntesis química , Límite de Detección , Miel/análisis , Polímeros/química , Polímeros/síntesis química , Contaminantes Químicos del Agua/análisis , Ríos/química , Espectrometría de Fluorescencia , Concentración de Iones de HidrógenoRESUMEN
In this study, a highly efficient CoFe2O4-anchored g-C3N4 nanocomposite with Z-scheme photocatalyst was developed by facile calcination and hydrothermal technique. To evaluate the crystalline structure, sample surface morphology, elemental compositions, and charge conductivity of the as-synthesized catalysts by various characterization techniques. The high interfacial contact of CoFe2O4 nanoparticles (NPs) with g-C3N4 nanosheets reduced the optical bandgap from 2.67 to 2.5 eV, which improved the charge carrier separation and transfer. The photo-degradation of methylene blue (MB) and rhodamine B (Rh B) aqueous pollutant suspension under visible-light influence was used to investigate the photocatalytic degradation activity of the efficient CoFe2O4/g-C3N4 composite catalyst. The heterostructured spinel CoFe2O4 anchored g-C3N4 photocatalysts (PCs) with Z-scheme show better photocatalytic degradation performance for both organic dyes. Meanwhile, the efficiency of aqueous MB and Rh B degradation in 120 and 100 min under visible-light could be up to 91.1% and 73.7%, which is greater than pristine g-C3N4 and CoFe2O4 catalysts. The recycling stability test showed no significant changes in the photo-degradation activity after four repeated cycles. Thus, this work provides an efficient tactic for the construction of highly efficient magnetic PCs for the removal of hazardous pollutants in the aquatic environment.
Asunto(s)
Cobalto , Compuestos Férricos , Azul de Metileno , Nanocompuestos , Rodaminas , Contaminantes Químicos del Agua , Cobalto/química , Compuestos Férricos/química , Catálisis , Nanocompuestos/química , Rodaminas/química , Contaminantes Químicos del Agua/química , Azul de Metileno/química , Fotólisis , Luz , Compuestos Inorgánicos de Carbono/química , Nitrilos/química , Procesos Fotoquímicos , Compuestos de Nitrógeno/química , GrafitoRESUMEN
The release of industrial wastewater has adverse effects on both aquatic ecosystems and the environment. Discharging untreated organic dyes into aquatic environments significantly amplifies pollution levels in these ecosystems. Ensuring the appropriate disposal of organic colorants and their derivatives before introducing them into wastewater streams is essential to prevent environmental contamination. This study aimed to develop an eco-friendly and sustainable approach to synthesize a chitosan-functionalized silver (Ag) nanocomposite using Solanum trilobatum for color pollutant mitigation. The synthesized CS-Ag nanocomposite was analyzed using various techniques such as UV-visible, FTIR, TEM, and EDS. TEM analysis revealed that the CS-Ag nanocomposite had a spherical nanostructure, with diameters ranging from 17.4 to 43.9 nm. These nanocomposites were tested under visible light irradiation to analyze their photocatalytic character against Congo red (CR). The nanocomposite exhibited a remarkable dye removal efficiency of over 93.6% within 105 min under irradiation. In the experimental recycling study, the CS-Ag nanocomposites demonstrated remarkable stability and reusability. Furthermore, the CS-Ag nanocomposite exhibited promising inhibition activity against bacterial pathogens. Our research revealed that the synthesized nanocomposite has the potential to act as a highly effective photocatalyst and bactericidal agent in various industrial and clinical applications.
Asunto(s)
Antibacterianos , Quitosano , Colorantes , Nanocompuestos , Plata , Contaminantes Químicos del Agua , Quitosano/química , Nanocompuestos/química , Plata/química , Antibacterianos/farmacología , Antibacterianos/química , Colorantes/química , Contaminantes Químicos del Agua/química , Catálisis , Rojo Congo/química , Restauración y Remediación Ambiental/métodos , Aguas Residuales/química , LuzRESUMEN
A simple sol-gel combustion process was employed for the creation of MFe2O4 (M=Ni, Co) nanoparticles. The synthesized nanoparticles, acting as both photocatalysts and gas sensors, were analyzed using various analytical techniques. MFe2O4 (M=Ni, Co) material improved the degradation of methylene blue (MB) under UV-light irradiation, serving as an enhanced electron transport medium. UV-vis studies demonstrated that NiFe2O4 achieved a 60% degradation, while CoFe2O4 nanostructure exhibited a 76% degradation efficacy in the MB dye removal process. Furthermore, MFe2O4 (M=Ni, Co) demonstrated chemosensitive-type sensor capabilities at ambient temperature. The sensor response and recovery times for CoFe2O4 at a concentration of 100 ppm were 15 and 20, respectively. Overall, the synthesis of MFe2O4 (M=Ni, Co) holds the potential to significantly improve the photocatalytic and gas sensing properties, particularly enhancing the performance of CoFe2O4. The observed enhancements make honey MFe2O4 (M=Ni, Co) a preferable choice for environmental remediation applications.
Asunto(s)
Cobalto , Compuestos Férricos , Azul de Metileno , Níquel , Cobalto/química , Cobalto/análisis , Níquel/química , Níquel/análisis , Compuestos Férricos/química , Azul de Metileno/química , Nanopartículas del Metal/química , Gases , Catálisis , Rayos Ultravioleta , Restauración y Remediación Ambiental/métodos , Nanopartículas/química , Óxido de Aluminio , Óxido de MagnesioRESUMEN
The presence of toxic trace elements (TEs) has resulted in a worldwide deterioration in freshwater ecosystem quality. This study aimed to analyze the distribution of TEs, including chromium (Cr), nickel (Ni), arsenic (As), mercury (Hg), cadmium (Cd), and lead (Pb), in water, sediment, and organs of Tilapia (Oreochromis mossambicus) collected from selected inland water bodies in Tamil Nadu, India. The water samples exhibited a range of concentrations for TEs: Cr varied from 0.014 to 5.193 µg/L, Ni ranged from 0.283 to 11.133 µg/L, As ranged from 0.503 to 1.519 µg/L, Cd from 0.001 to 0.616 µg/L, and Pb ranged from non-detectable (ND) to 6.103 µg/L. The concentrations of TEs in sediment were found to vary within the following ranges: 5.259 to 32.621 mg/kg for Cr, 1.932 to 30.487 mg/kg for Ni, 0.129 to 0.563 mg/kg for As, 0.003 to 0.011 mg/kg for Cd, ND to 0.003 mg/kg for Hg, and 0.404 to 1.575 mg/kg for Pb. The study found that the accumulation pattern of TE in fishes across all selected areas was liver > bone > gill > muscle. The organs had TE concentrations of Cr (ND-0.769 mg/kg), Ni (ND-1.053 mg/kg), As (0.002-0.080 mg/kg), Pb (ND-0.411 mg/kg), and Hg (ND-0.067 mg/kg), which was below the maximum residual limit prescribed by EC and FSSAI. The bioconcentration factor (BCF) of TEs exhibited a greater magnitude in comparison with the biota-sediment accumulation factor due to the higher concentration of TEs in fish and lower level in water. The assessment of both carcinogenic and non-carcinogenic risks suggests that the consumption of Tilapia from the study region does not pose any significant risks.
Asunto(s)
Bioacumulación , Sedimentos Geológicos , Tilapia , Oligoelementos , Contaminantes Químicos del Agua , Animales , Tilapia/metabolismo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo , Medición de Riesgo , Sedimentos Geológicos/química , Oligoelementos/análisis , Oligoelementos/metabolismo , India , Monitoreo del Ambiente , Metales Pesados/análisis , Humanos , Agua DulceRESUMEN
Advancement in bioinspired alloy nanomaterials has a crucial impact on fuel cell applications. Here, we report the synthesis of PtPd alloy nanoclusters via the hydrothermal method using Piper longum extract, representing a novel and environmentally friendly approach. Physicochemical characteristics of the synthesized nanoclusters were investigated using various instrumentation techniques, including X-ray photoelectron spectroscopy, X-ray diffraction, and High-Resolution Transmission electron microscopy. The electrocatalytic activity of the biogenic PtPd nanoclusters towards the oxidation of formic acid and methanol was evaluated chronoamperometry and cyclic voltammetry studies. The surface area of the electrocatalyst was determined to be 36.6 m2g-1 by Electrochemical Surface Area (ECSA) analysis. The biologically inspired PtPd alloy nanoclusters exhibited significantly higher electrocatalytic activity compared to commercial Pt/C, with specific current responses of 0.24 mA cm - 2 and 0.17 mA cm - 2 at synthesis temperatures of 180 °C and 200 °C, respectively, representing approximately four times higher oxidation current after 120 min. This innovative synthesis approach offers a promising pathway for the development of PtPd alloy nanoclusters with enhanced electrocatalytic activity, thereby advancing fuel cell technology towards a sustainable energy solution.
Asunto(s)
Formiatos , Metanol , Piper , Aleaciones , Extractos VegetalesRESUMEN
Plastic waste has become a global issue and a threat to the ecosystem. The present study isolated polyurethane (PU) degrading bacterial species from soil dumped with plastic wastes. Four bacterial isolates, RS1, RS6, RS9 and RS13 were obtained and their ability to degrade PU in a synthetic medium with PU as a sole source of carbon was assessed individually. After thirty days of incubation, the highest PU weight loss of 67.36 ± 0.32% was recorded in the medium containing RS13 isolate. The results of FTIR revealed the occurrence of carbonyl peaks. The putative isolate RS13 confirmed with the genus Moraxella according to 16S rRNA gene sequencing and the isolate was specified as Moraxella catarrhalis strain BMPPS3. The restriction analysis of Moraxella catarrhalis strain BMPPS3 revealed that the GCAT content to 51% and 49% correspondingly. Moraxella catarrhalis strain BMPPS3 was able to colonize on PU surface and form a biofilm as revealed by SEM investigation. Fatty acids and alkanes were found to be the degradation products by GC-MS analysis. The presence of these metabolites facilitated the growth of strain RS13 and suggested that ester hydrolysis products had been mineralized into CO2 and H2O. Extracellular biosurfactant synthesis has also been found in Moraxella catarrhalis strain BMPPS13 inoculated with synthetic media and mineral salt media containing PU and glucose as carbon sources, respectively with a significant level of cell-surface hydrophobicity (32%). The production and activity of extracellular esterase showed consistent increase from day 1-15 which peaked (1.029 mM/min/mg) on day 24 significantly at P < 0.001. Crude biosurfactants were lipopeptide-based, according to the characteristic investigation. According to this study findings, Moraxella catarrhalis produces biosurfactants of the esterase, urethanase and lipase (lipopeptide) types when carbon source PU is present.
Asunto(s)
Biodegradación Ambiental , Moraxella catarrhalis , Poliuretanos , Moraxella catarrhalis/genética , Moraxella catarrhalis/metabolismo , Moraxella catarrhalis/enzimología , Microbiología del Suelo , ARN Ribosómico 16S/genética , Biopelículas/crecimiento & desarrolloRESUMEN
The migration of organochlorine pesticides (OCPs) and cypermethrin residues from internal organs to edible tissues of ice-held Labeo rohita (rohu) was investigated in this study. The liver (246 µg/kg) had the highest level of ∑OCP residues, followed by the gills (226 µg/kg), intestine (167 µg/kg), and muscle tissue (54 µg/kg). The predominant OCPs in the liver and gut were endosulfan (53-66 µg/kg), endrin (45-53 µg/kg), and dichloro-diphenyl-trichloroethane (DDT; 26-35 µg/kg). The ∑OCP residues in muscle increased to 152 µg/kg when the entire rohu was stored in ice, but they decreased to 129 µg/kg in gill tissues. On days 5 and 9, the total OCPs in the liver increased to 317 µg/kg and 933 µg/kg, respectively. Beyond day 5 of storage, total internal organ disintegration had led to an abnormal increase in OCP residues of liver-like mass. Despite a threefold increase in overall OCP residues by day 9, accumulation of benzene hexachloride (BHC) and heptachlor was sixfold, endrin and DDT were fourfold, aldrin was threefold, and endosulfan and cypermethrin were both twofold. Endosulfan, DDT, endrin, and heptachlor were similarly lost in the gills at a rate of 40%, while aldrin and BHC were also lost at 60 and 30%, respectively. The accumulation of OCP residues in tissues has been attributed to particular types of fatty acid derivatives. The study concluded that while pesticide diffusion to edible tissues can occur during ice storage, the levels observed were well below the allowable limit for endosulfan, endrin, and DDT.
Asunto(s)
Hidrocarburos Clorados , Residuos de Plaguicidas , Plaguicidas , Piretrinas , Animales , Aldrín/análisis , DDT/análisis , Endosulfano/toxicidad , Endosulfano/análisis , Endrín , Monitoreo del Ambiente , Heptacloro/análisis , Hexaclorociclohexano , Hidrocarburos Clorados/toxicidad , Hidrocarburos Clorados/análisis , Hielo , Residuos de Plaguicidas/análisis , Plaguicidas/toxicidad , Plaguicidas/análisisRESUMEN
This study assesses the bioaccumulation, ecological, and health risks associated with potentially toxic metals (PTMs), including Pb, Hg, Cd, As, and Cr in Hare Island, Thoothukudi. The results revealed that the concentration of PTMs in sediment, seawater, and S. wightii ranged from 0.095 to 2.81 mg kg-1, 0.017 to 1.515 mg L-1, and 0.076 to 5.713 mg kg-1, respectively. The highest concentrations of PTMs were found in the S. wightii compared to seawater and sediment. The high bioaccumulation of Hg and As in S. wightii suggests that it can be used as a bioindicator for these elements in this region. The ecological risk indices, which include individual, complex, biological, and ecological pollution indices, suggest that Hare Island had moderate contamination with Hg and Cd. However, there are no human health risks associated with PTMs. This study examines the current ecological and health risks associated with PTMs and emphasizes the importance of regular monitoring.
Asunto(s)
Liebres , Mercurio , Algas Marinas , Humanos , Animales , Bioacumulación , Cadmio , Agua de MarRESUMEN
The present study is an attempt to investigate the potentiality of Rhizoclonium hieroglyphicum in the removal of reactive red 239 (RR239) from aqueous solution and to assess the toxicity of the treated dye solution. Optimisation of the process variables namely dye and biosorbent concentrations, pH, temperature and incubation time for RR239 removal was performed using Response Surface Methodology (RSM) assisted Box Behnken Design (BBD) model. The recycling and regeneration efficiency of the dye adsorbed alga was evaluated using different eluents under optimized conditions. Further to understand the adsorption mechanism, isotherms, kinetics and thermodynamic studies were performed. UV-vis and FT-IR spectroscopy was employed to confirm the interaction between the adsorbate and biosorbent. The nature of the treated dye solution was assessed using phyto, microbial and brine shrimp toxicity studies. On the basis of quadratic polynomial equation and response surfaces given by RSM, 90% decolorization of RR239 was recorded at room temperature under specified optimal conditions (300 mg/L of dye, 500 mg/L of biosorbent, pH 8 and 72 h of contact time). Desorption experiments demonstrated 88% of RR239 recovery using 0.1 N acetic acid as an eluent and 81% of dye removal in regeneration studies. The data closely aligned with Freundlich isotherm (R2 - 0.98) and pseudo-second-order kinetic model (R2 - 0.9671). Thermodynamic analysis revealed that the process of adsorption was endothermic, spontaneous, and favorable. UV-Vis and FT-IR analyses provided evidence for adsorbate-biosorbent interaction, substantiating the process of decolorization. In addition, the results of phyto, microbial and brine shrimp toxicity assays consistently confirmed the non-toxic nature of the treated dye. Thus, the study demonstrated that R. hieroglyphicum can act as a potent bioremediation agent in alleviating the environmental repercussions of textile dyeing processes.
Asunto(s)
Chlorophyta , Animales , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Temperatura , Ácido Acético , ArtemiaRESUMEN
The removal of color-causing compounds from wastewater is a significant challenge that industries encounter due to their toxic, carcinogenic, and harmful properties. Despite the extensive research and development of various techniques with the objective of effectively degrading color pollutants, the challenge still persists. This paper introduces a simple technique for producing iron oxide nanoparticles (Fe2O3 NPs) using orange fruit peel for sustainable dye degradation in aqueous environment. The observation of color change and the measurement of UV-visible absorbance at 240 nm provided a confirmation for the development of Fe2O3 NPs. Transmission electron microscopy examination demonstrated that the Fe2O3 NPs have an agglomerated distribution and forming spherical structures with size ranging from 25-80 nm. Energy-dispersive X-ray spectroscopy analysis supported the existence of Fe and O. Fourier transform infrared spectroscopy conducted to investigate the involvement of orange peel extract in the reduction, capping, and synthesis of Fe2O3 NPs from the precursor salt. Fe2O3 NPs showed a photocatalytic remediation of 97%, for methylene blue under visible light irradiation. Additionally, prepared NPs exhibited concentration depended biofilm inhibition action against E. coli and S. aureus. In conclusion, Fe2O3 NPs can efficiently purify water and suppress pathogens due to their strong degrading activity, reusability, and biofilm inhibition property.
Asunto(s)
Contaminantes Ambientales , Aguas Residuales , Escherichia coli , Frutas , Staphylococcus aureus , Nanopartículas Magnéticas de Óxido de Hierro , Extractos VegetalesRESUMEN
Industrial processes result in the production of heavy metals, dyes, pesticides, polyaromatic hydrocarbons (PAHs), pharmaceuticals, micropollutants, and PFAS (per- and polyfluorinated substances). Heavy metals are currently a significant problem in drinking water and other natural water bodies, including soil, which has an adverse impact on the environment as a whole. The heavy metal is highly poisonous, carcinogenic, mutagenic, and teratogenic to humans as well as other animals. Multiple polluted sites, including terrestrial and aquatic ecosystems, have been observed to co-occur with heavy metals and organo-pollutants. Pesticides and heavy metals can be degraded and removed concurrently from various metals and pesticide-contaminated matrixes due to microbial processes that include a variety of bacteria, both aerobic and anaerobic, as well as fungi. Numerous studies have examined the removal of heavy metals and organic-pollutants from different types of systems, but none of them have addressed the removal of these co-occurring heavy metals and organic pollutants and the use of microbes to do so. Therefore, the main focus of this review is on the recent developments in the concurrent microbial degradation of organo-pollutants and heavy metal removal. The limitations related to the simultaneous removal and degradation of heavy metals and organo-pollutant pollutants have also been taken into account.
Asunto(s)
Contaminantes Ambientales , Metales Pesados , Plaguicidas , Contaminantes del Suelo , Humanos , Animales , Ecosistema , Metales Pesados/metabolismo , Bacterias/metabolismo , Plaguicidas/metabolismo , Contaminantes del Suelo/metabolismo , Biodegradación AmbientalRESUMEN
Atomic scale understanding of defect induced magnetic interactions resulting in lattice disordering has been deduced in a detailed manner for the first time in Co2Fe0.5Cr0.5Al based on Mössbauer spectroscopic studies and compared with the results obtained in Co2Fe0.8Cr0.2Al and Co2FeAl. An interesting linear correlation between valence electron concentration and the mean hyperfine fields at Fe sites in Co2FeAl based compounds has been deduced which is observed to exhibit different slopes with the substitution of Cr. This study elucidates an important role of the manifestation of the magnetic interactions especially between Fe, Co and Cr atoms leading to significant changes in the concentration and specific types of defects selectively produced in Co2Fe0.5Cr0.5Al as compared with that of Co2Fe0.8Cr0.2Al subjected to similar non-equilibrium treatments in this study. Further, for the first time this study elucidates the striking correlation of the effective value of the hyperfine field with the degree of ordering/disordering of the lattice with the Fe atoms associated with ordered sites experiencing a much higher value of the hyperfine field as compared to that of the disordered sites. This study also proposes optimal annealing treatment for the recovery of defects in Co2Fe0.5Cr0.5Al, which would be of significant importance in these spintronic materials.
RESUMEN
Exopolysaccharides (EPS) are produced by probiotic bacteria Lactiplantibacillus plantarum PRK7 and L. plantarum PRK11. The structure of EPS-7 and EPS-11 was characterized by Fourier-transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), gas chromatography-mass spectroscopy (GCMS), and thermogravimetric analysis (TGA). Further, in in vitro studies antioxidant, emulsion, and antibiofilm activity were investigated. The FTIR spectrum confirmed the presence of polysaccharides in EPS-7 and EPS-11, with absorbance at 1654.93 and 1655.33 cm-1, respectively. H1 NMR further confirmed the presence of glucose, galactose, xylose, and mannose. Sugar derivatives in EPS-7 and EPS-11 were further confirmed with GCMS. The SEM analysis revealed that EPS-7 had a weblike structure and EPS-11 had a smooth porous layer. The result of the TGA revealed that EPS-7 and EPS-11 had greater thermal stability at 319.1 and 300.1 °C, respectively. Furthermore, EPS-7 and EPS-11 showed a good percentage of free radical scavenging in DPPH (89.77 % and 93.1 %), ABTS (57.65 % and 58.63 %), hydroxyl radical scavenging (44.46 % and 40.308 %), and reducing power assay. The emulsion activity was confirmed with edible oils such as coconut oil, sesame oil, almond oil, castor oil, and neem oil. The highest emulsion activity for EPS-7 and EPS-11 was found with coconut and castor oil. In addition, the antibiofilm activity against pathogens revealed that EPS can prevent biofilm formation. Thus, it was found that EPS-7 and EPS-11 possess good structural characteristics and their biological activity makes them ideal for applications in the food and pharmaceutical industry.
Asunto(s)
Antioxidantes , Polisacáridos Bacterianos , Antioxidantes/farmacología , Antioxidantes/química , Polisacáridos Bacterianos/farmacología , Polisacáridos Bacterianos/química , Emulsiones , Espectroscopía Infrarroja por Transformada de Fourier , BiopelículasRESUMEN
The impact of ZnO/SnO2/reduced graphene oxide nanocomposites (ZnO/SnO2/rGO NCs) for improved photocatalytic degradation of organic dye pollution is examined in this study. The developed ternary nanocomposites had a variety of characteristics that were detected, such as crystallinity, recombination of photogenerated charge carriers, energy gap, and surface morphologies. When rGO was added to the mixture, the optical band gap energy of ZnO/SnO2 was lowered, which improved the photocatalytic activity. Additionally, in comparison to ZnO, ZnO/rGO, SnO2/rGO samples, the ZnO/SnO2/rGO nanocomposites demonstrated exceptional photocatalytic effectiveness for the destruction of orange II (99.8%) and reactive red 120 dye (97.02%), respectively after 120 min exposure to sunlight. The high electron transport properties of the rGO layers, which make it feasible to efficiently separate electron-hole pairs, are attributed to the enhanced photocatalytic activity of the ZnO/SnO2/rGO nanocomposites. According to the results, synthesized ZnO/SnO2/rGO nanocomposites are a cost-efficient option for removing dye pollutants from an aqueous ecosystem. Studies show that ZnO/SnO2/rGO nanocomposites are effective photocatalysts and may one day serve as the ideal material to reduce water pollution.
Asunto(s)
Contaminantes Ambientales , Nanocompuestos , Óxido de Zinc , EcosistemaRESUMEN
Eco-friendly renewable energy sources have recommended as fossil fuel alternatives in recent years to reduce environmental pollution and meet future energy demands in various sectors. As the largest source of renewable energy in the world, lignocellulosic biomass has received considerable interest from the scientific community to advance the fabrication of biofuels and ultrafine value-added chemicals. For example, biomass obtained from agricultural wastes could catalytically convert into furan derivatives. Among furan derivatives, 5-hydroxymethylfurfural (HMF) and 2, 5-dimethylfuran (DMF) are considered the most useful molecules that can be transformed into desirable products such as fuels and fine chemicals. Because of its exceptional properties, e.g., water insolubility and high boiling point, DMF has studied as the ideal fuel in recent decades. Interestingly, HMF, a feedstock upgraded from biomass sources can easily hydrogenate to produce DMF. In the present review, the current state of the art and studies on the transformation of HMF into DMF using noble metals, non-noble metals, bimetallic catalysts, and their composites have discussed elaborately. In addition, comprehensive insights into the operating reaction conditions and the influence of employed support over the hydrogenation process have demonstrated.
Asunto(s)
Biocombustibles , Lignina , Biomasa , Lignina/química , FuranosRESUMEN
For wastewater treatment, a highly reliable and ecologically friendly oxidation method is always preferred. This work described the production of a new extremely effective visible light-driven Ag2Ox loaded ZnFe2O4 nanocomposties photocatalyst using a wet impregnation technique. Under visible light irradiation, the produced Ag2Ox loaded ZnFe2O4 nanocomposties were used in the photodegradation of rhodamine B (RhB) and Reactive Red 120 (RR120) dyes. Analysis using X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy revealed that Ag2Ox nanoparticles were well dispersed on the surface of ZnFe2O4 NPs and that the Ag2Ox loaded ZnFe2O4 NPs were created. When compared with bare ZnFe2O4 NPs, Ag2Ox-loaded ZnFe2O4 nanocomposites showed better photocatalytic activity for RhB and RR120 degradation under visible light (>420 nm) illumination. The reaction kinetics and degradation methodology, in addition to the photocatalytic degradation functions of Ag2Ox-loaded ZnFe2O4 nanocomposites, were thoroughly investigated. The 3 wt% Ag2Ox loaded ZnFe2O4 nanocomposites have a 99% removal efficiency for RhB and RR120, which is about 2.4 times greater than the ZnFe2O4 NPs and simple combination of 1 wt% and 2 wt% Ag2Ox loaded ZnFe2O4 nanocomposites. Furthermore, the 3 wt% Ag2Ox loaded ZnFe2O4 nanocomposites demonstrated consistent performance without decreasing activity throughout 3 consecutive cycles, indicating a potential approach for the photo-oxidative destruction of organic pollutants as well as outstanding antibacterial capabilities. According to the findings of the experiments, produced new nanoparticles are an environmentally friendly, cost-efficient option for removing dyes, and they were successful in suppressing the development of Gram-negative and Gram-positive bacteria.
Asunto(s)
Contaminantes Ambientales , Óxidos , Luz , Bacterias , Colorantes , CatálisisRESUMEN
An ever-increasing use of pesticides in agricultural fields has led to a catastrophic decline in crop quality and, ultimately soil fertility. To control various pests, quinalphos is commonly used in India's tea plantations. This study aims to investigate the effects of the Quinalphos organophosphate insecticide on the non-target beneficial organism Eudrilus eugeniae earthworms and the biomarkers that respond to its effects. Earthworm species, especially E. eugeniae, remains as the most trustworthy and well-suited model organism for conducting a wide variety of environmental studies. The median lethal concentration (LC50) was identified as 3.561 µg cm-2 (contact filter paper) and 1.054 mg kg-2 (artificial soil toxicity). The 5% and 10% of LC50 value 3.561 µg cm-2 was exposed to earthworm to analyze the sublethal effects at pre-clitellum, clitellum, and post-clitellum segments. Specific enzymatic activities of neurotransmitter enzyme acetylcholinesterase; antioxidant enzymes such as lipid peroxidase, superoxide dismutase, and catalase; and detoxification enzymes including glutathione S transferase, reduced glutathione, carboxylesterase, and Cytochrome P450 were analyzed. Exposure of E. eugeniae earthworm to subacute exposures of pesticides caused significant alterations in these stress markers in a concentration-dependent manner. Morphological abnormalities like bulginess, coiling, and bleeding were observed after exposure of the insecticide treatments. Histological cellular disintegration, a reduced NRRT time, and an inhibited proteolytic zone were also identified in pesticide-exposed earthworms. Studies demonstrate that the organophosphate insecticide quinalphos causes acute toxicity in E. eugeniae; hence, it is suggested that non-target eco-friendly E. eugeniae earthworms may be at risk if exposed to the excessive concentrations of quinalphos organophosphate insecticide in soil.