Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
1.
Environ Geochem Health ; 46(6): 187, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38696018

RESUMEN

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 Dulce
2.
Environ Geochem Health ; 46(2): 30, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38227286

RESUMEN

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 Vegetales
3.
Environ Res ; 242: 117753, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38008204

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are potentially hazardous compounds that could cause a severe impact on many ecosystems. They are very challenging to remove using conventional methods due to their hydrophobic nature. However, this issue can be resolved by utilizing surface-active molecules to increase their bioavailability. In this study, pyrene was chosen as the PAH compound to explore its degradability by the effect of individual bacterial strains (Pseudomonas stutzeri NA3 and Acinetobacter baumannii MN3) and mixed consortia (MC) along with natural surfactant derived from Sapindus mukorossi and iron oxide nanoparticles (NPs). Additionally, fatty acids esters, dipeptides, and sugar derivative groups were identified as potent bioactive components of natural surfactants. Various techniques, such as XRD, VSM, TEM, and FE-SEM with EDX, were utilized to characterize the pristine and Fenton-treated iron oxide NPs. The analytical results confirmed that the Fe3O4 crystal phase and spherical-shaped NPs exhibited excellent magnetic properties. The impact of natural surfactants and iron oxide NPs has significantly contributed to the biodegradation process, resulting in a prominent decrease in chemical oxygen demand (COD) levels. Gas chromatography-mass spectrometry (GC-MS) analysis showed that biodegradation systems produced primary hydrocarbon intermediates, which underwent oxidative degradation through Fenton treatment. Interestingly, synthesized iron oxide NPs effectively produced hydroxyl radical (•OH) during the Fenton reaction, which was confirmed by electron paramagnetic resonance (EPR) spectra, and the pristine iron oxide NPs underwent a material transformation observed. The study demonstrated an integrated approach for biodegradation and the Fenton reaction process to enhance the pyrene degradation efficiency (90%) compared to other systems. Using natural surfactants and iron oxide NPs in aquatic environments serves as a crucial platform at the interface of microorganisms and contaminated oil products. This interaction offers a promising solution for PAHs bioremediation.


Asunto(s)
Compuestos Férricos , Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Tensoactivos/química , Biodegradación Ambiental , Ecosistema , Contaminantes del Suelo/análisis , Pirenos/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Bacterias/metabolismo , Nanopartículas Magnéticas de Óxido de Hierro
4.
Environ Res ; 244: 117911, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38104919

RESUMEN

Poly aromatic hydrocarbons (PAHs) are considered as hazardous compounds which causes serious threat to the environment dua to their more carcinogenic and mutagenic impacts. In this study, Pseudomonas aeruginosa PP4 strain and synthesized iron nanoparticles were used to evaluate the biodegradation efficiency (BE %) of residual anthracene. The BE (%) of mixed degradation system (Anthracene + PP4+ FeNPs) was obtained about 67 %. The FTIR spectra result revealed the presence of functional groups (C-H, -CH3, CC, =C-H) in the residual anthracene. The FESEM and TEM techniques were used to determine the surface analysis of the synthesized FeNPs and the average size was observed by TEM around 5-50 nm. The crystalline nature of the synthesized iron nanoparticles was confirmed by the observed different respective peaks of XRD pattern. The various functional constituents (OH, C-H, amide I, CH3) were identified in the synthesized iron nanoparticles by FTIR spectrum. In conclusion, this integrated nano-bioremediation approach could be an promising and effective way for many environmental fields like cleanup of hydrocarbon rich environment.


Asunto(s)
Antracenos , Pseudomonas aeruginosa , Antracenos/metabolismo , Hierro , Biodegradación Ambiental , Nanopartículas Magnéticas de Óxido de Hierro
5.
ACS Omega ; 8(44): 41054-41063, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37970029

RESUMEN

Poly(vinyl alcohol) (PVA), a naturally occurring and rapidly decomposing polymer, has gained significant attention in recent studies for its potential use in pollution preventive materials. Its cost-effectiveness and ease of availability as well as simple processing make it a suitable material for various applications. However, the only concern about PVA's applicability to various applications is its hydrophilic nature. To address this limitation, PVA-based nanocomposites can be created by incorporating inorganic fillers such as graphene (G). Graphene is a two-dimensional carbon crystal with a single atom-layer structure and has become a popular choice as a nanomaterial due to its outstanding properties. In this study, we present a simple and environmentally friendly solution processing technique to fabricate PVA and graphene-based nanocomposite films. The resulting composite films showed noticeable improvement in barrier properties against moisture, oxygen, heat, and mechanical failures. The improvement of the characteristic properties is attributed to the uniform dispersion of graphene in the PVA matrix as shown in the SEM image. The addition of graphene leads to a decrease in water vapor transmission rate (WVTR) by 79% and around 90% for the oxygen transmission rate (OTR) as compared to pristine PVA films. Notably, incorporating just 0.5 vol % of graphene results in an OTR value of as low as 0.7 cm m-2 day-1 bar-1, making it highly suitable packaging applications. The films also exhibit remarkable flexibility and retained almost the same WVTR values even after going through tough bending cycles of more than 2000 at a bending radius of 2.5 cm. Overall, PVA/G nanocomposite films offer promising potential for PVA/G composite films for various attractive pollution prevention (such as corrosion resistant coatings) and packaging applications.

6.
Chemosphere ; 344: 140340, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37778647

RESUMEN

Biosurfactants are surface active molecules generated by various microorganisms, including bacteria, actinobacteria, algae, and fungi. In this study, bacterial strains are isolated from soil contaminated with used motor oil and examined for potential biosurfactant production. A minimum salt medium (MSM), with crude oil as the only carbon source, is used to isolate potential biosurfactant-producing bacterial strains. About 23 strains are isolated, and all are subjected to the primary screening methods for biosurfactant production. Based on the emulsification index, oil displacement, and drop collapse screening methods, two isolates with potential biosurfactant-producing ability are selected for further studies. The synthesis of biosurfactants, crude oil and anthracene biodegradation is carried out with strains DTS1 and DTS2. Both strains show significant outcomes in crude oil degradation. In addition, both strains can utilize anthracene as the sole carbon source. During the degradation course, changes in the growth conditions are continuously monitored by measuring turbidity and pH. In this degradation study, the biosurfactant production aptitude of the isolated strains plays an essential role in increasing the bioavailability of hydrophobic hydrocarbons. These strains are identified down to the molecular level by employing 16S rRNA gene sequencing, and the acquired sequences are submitted to get the accession numbers. These prospective strains can be utilized to remediate hydrocarbon-contaminated environments.


Asunto(s)
Bacillus , Petróleo , Bacillus/metabolismo , Petróleo/análisis , ARN Ribosómico 16S/genética , Estudios Prospectivos , Tensoactivos/química , Bacterias/metabolismo , Hidrocarburos/metabolismo , Biodegradación Ambiental , Antracenos/metabolismo , Carbono/metabolismo
7.
Chemosphere ; 345: 140513, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37890794

RESUMEN

To degrade anthracene, magnetite nanoparticles were produced using a simple co-precipitation process. The fabricated nanoparticles have been analyzed for structural and optical properties. XRD examination revealed that the produced Fe3O4 nanoparticles were cubic phase, having a mean crystallite dimension of 18.84 nm. DLS determined the hydrodynamic diameter of Fe3O4 nanoparticles to be 182 nm. UV-Vis research revealed that Fe3O4 nanoparticles absorb at 390 nm. A peak at 895 cm-1 in the FT-IR study indicated the metal-oxygen connection. The synthesized Fe3O4 nanoparticles demonstrated an effective photocatalytic performance towards anthracene degradation and was found to be 86.55%. Furthermore, Fe3O4 nanoparticles showed the highest antimicrobial activity against Bacillus subtilis was 19.43 mm. The present study is the first and foremost study determining the dual role of Fe3O4 nanoparticles towards bioremediation and biomedical applications.


Asunto(s)
Antiinfecciosos , Nanopartículas de Magnetita , Hidrocarburos Policíclicos Aromáticos , Espectroscopía Infrarroja por Transformada de Fourier , Nanopartículas de Magnetita/química , Antiinfecciosos/farmacología , Antracenos
8.
Chemosphere ; 343: 140123, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37690563

RESUMEN

MnO2 nanoparticles have a wide range of applications, including catalytic abilities due to their oxygen reduction potential. Industrial processes and the burning of organic materials released PAHs into the biosphere which have adverse effects on living organisms when continually exposed. In this study, MnO2 nanoparticles were synthesized chemically using sodium thiosulphate as reducing agent. MnO2 nanoparticles were characterized using UV-visible adsorption spectroscopy and Fourier Transform Infrared Spectroscopy (FTIR). A X-Ray Diffraction Spectrophotometer (XRD), a Scanning Electron Microscopy - Energy Dispersive X-Ray Analyzer (SEM-EDAX), and Dynamic Light Scattering (DLS) were used to identify the crystalline nature and particle size of the fabricated MnO2 nanoparticles. Batch adsorption studies were conducted to identify the optimal conditions for better benzene and pyrene adsorption from aqueous solution using MnO2 nanoparticles. They are also effective in degrading benzene and pyrene by batch adsorption as determined by their adsorption isotherms and kinetics.

9.
Environ Res ; 236(Pt 1): 116718, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37481060

RESUMEN

In ancient times, herbal plants were considered one of the greatest gifts from nature that human beings could receive, and about 80% of these plants have medicinal uses. In traditional medicine, Mentha arvensis, commonly known as mint, has many applications, and in the present study, the mint leaf extract has been used to synthesis nanoparticles using the mint leaf extract as a biosource for the extraction of nanoparticles. In addition to having a wide range of applications in various fields, calcium oxide (CaO) nanoparticles are also considered to be safe for human use. In order to assess the characteristics of the abstracted CaO nanoparticles, UV-visible absorption spectrophotometers, Fourier Transform Infrared spectrophotometers (FTIR), Scanning Electron Microscopes (SEMs), Dynamic Light Scattering (DLS), and X-ray Diffraction Spectrophotometers (XRDs) were used. By conducting a protein denaturation assay and nitric oxide scavenging assay, mint leaf mediated CaO nanoparticles were evaluated for their therapeutic applications. MTT assays were used to prove that the CaO nanoparticles mediated by mint leaf had anti-cancer properties. By examining the ability of mint leaf mediated CaO nanoparticles to degrade various dyes such as methyl red, methyl orange, and methylene blue, which are the most used azo dyes in textile industries resulting in water contamination, the ability of these nanoparticles to act as a photocatalytic agent was examined.


Asunto(s)
Mentha , Nanopartículas del Metal , Nanopartículas , Humanos , Extractos Vegetales/farmacología , Colorantes , Difracción de Rayos X , Antiinflamatorios , Espectroscopía Infrarroja por Transformada de Fourier , Antibacterianos
10.
Environ Res ; 236(Pt 2): 116749, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37507040

RESUMEN

Nanotechnology is an emerging technology that uses medicinal plants to extract nanoparticles for conventional applications. In the present investigation, the medical plant Tulsi (Ocimum sanctum) has used in the synthesis of cobalt (Co) nanoparticles in a cost-effective, feasible process. The efficiency of nanoparticles in removing methyl orange dye was evaluated by analyzing their applications in wastewater treatment. An analysis of the anti-inflammatory and anti-cancer properties of Tulsi-mediated Co nanoparticles was conducted to examine their medical application. Morphological analysis of Co nanoparticles showed that the synthesized nanoparticles were in crystal shape with a mean particle size of 110 nm. A batch adsorption study has shown that incubation periods of 5 h, pH 2, temperatures of 70 °C, and adsorbent dosage of 125 µg/mL are optimal for removing methyl orange dye from wastewater. To examine the anti-inflammatory properties of Tulsi-mediated Co nanoparticles, protein denaturation and nitric oxide scavenging assays were performed. The maximum anti-inflammatory response was recorded at a concentration of 250 µg/mL of Co nanoparticles. MTT assays against MDA-MB-231 human breast cancer cells were used to evaluate the anti-cancer properties of Co nanoparticles. This study investigates the economical extraction of Co nanoparticles from tulsi and its potential use in wastewater purification and biomedical applications.

11.
Environ Res ; 227: 115723, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37003548

RESUMEN

Three-dimensional multi-porous Iron Oxide/carbon (Fe2O3/C) composites derived from tamarind shell biomass were synthesized by a single-step co-pyrolysis technique and utilized for Paracetamol (PAC) dismissal in the combined adsorption, and advanced oxidation such as electrochemical regeneration techniques. The Fe2O3/C composites were prepared by different pyrolysis temperatures, and named as TS750 (without Fe2O3at 750 °C), MTS450 BCs (Low-450 °C), MTS600 BCs (Moderate-600 °C) and MTS750 BCs (high-750 °C), respectively. As-prepared Fe2O3/C composite was characterized by FE-SEM, XRD, BET, and XPS analysis. The specific surface area and the spatial interaction between the interlayers of Fe2O3 and C were significantly improved by increasing the pyrolysis temperatures from 450 to 750 °C, which improved the adsorption capacity of Fe2O3/C composites in terms of higher rate constants and chemisorption kinetics. The Pseudo-second-order kinetics model fitted in the adsorption test results of Fe2O3/C composites with the highest correlation co-efficiency. The Langmuir-isotherms model fitted in the adsorption test of the TS750 and MTS450 BCs. The Freundlich isotherms model is more fit with MTS600 and MTS750 BCs. Based on the isotherm results, the MTS750 BCs achieved 46.9 mg/g of maximum PAC adsorption capacity. The optimized MTS750 composites could be completely recovered by using an advanced electrochemical oxidation regeneration approach within 180 min. Also, with the adsorption and recovery process, the TOC removal rate improved to ∼79.4%. After the 6th cycle electrochemical oxidation process, the obtained results of the re-adsorption test showed the stabile adsorption activity of the sorbent material. The data outcomes herein propose that this type of combined adsorption and electrochemical approach will be useful in commercial water treatment plants.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Hierro/química , Acetaminofén , Adsorción , Contaminantes Químicos del Agua/análisis , Carbono , Cinética , Purificación del Agua/métodos
12.
Chemosphere ; 323: 138179, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36849022

RESUMEN

In this study, aqueous and methanol extracts of Morinda coreia (MC) leaves were tested for antioxidant and antibacterial activity under in vitro conditions. Phytochemical analysis using UPLC-ESI-MS revealed the presence of phenolics, flavonoids, alkaloids, glycosides, amino acids, proteins, saponins, and tannins. Under in vitro conditions, antioxidant test using DPPH, ABTS, and reducing power demonstrated that the plant leaves play a crucial role in antioxidant activity compared to the commercial antioxidant butylated hydroxytoluene (BHT). The ABTS and DPPH free radical scavenging activities showed that the IC50 values of the M. coreia methanol extract were 26.35 µg/mL and 200.23 µg/mL, respectively. The methanol extract of M. coreia contained higher levels of total phenols and flavonoids and higher free radical scavenging capacity than the aqueous extract. FTIR analysis of the methanol extract showed a substantial number of phenols in the functional groups of M. coreia leaves. The well diffusion assay using the methanolic extract of M. coreia (200 µg/mL) leaves showed antibacterial activity against Pseudomonas aeruginosa (19 ± 0.85 mm), Proteus sp. (20 ± 0.97 mm), Streptococcus sp. (21 ± 1.29 mm), and Enterobacter sp. (17 ± 0.2 mm). Thus, the present study revealed that the antibacterial and antioxidant activity of M. coreia leaf extract was due to the presence of 18 unknown and 15 primary known polyphenols.


Asunto(s)
Antioxidantes , Morinda , Antioxidantes/análisis , Extractos Vegetales/farmacología , Extractos Vegetales/química , Metanol , Espectrometría de Masas en Tándem , Flavonoides/análisis , Antibacterianos/farmacología , Fenoles/análisis , Radicales Libres , Hojas de la Planta/química
13.
Chemosphere ; 319: 138024, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36731667

RESUMEN

In this study, liquid chromatography and mass spectrometry were used to screen the active phytochemicals and analyze antioxidant activity of Croton bonplandianum. In addition, cadmium telluride quantum dots were used to analyze the fluorescence quenching capabilities of Croton bonplandianum plants. UPLC-ESI-MS was used to screen polyphenols in the mass range of 100-2000, with both positive and negative ionizations. Based on molecular weight, 7-Spirostanoldihexoside isomer, Rutin, Quercetin hexoside, Kaempferol-3-O-(p-coumaroyl)-glucoside, Kaempferol, Quercetin, and (E) Catechin-(E) Gallocatechin were tentatively identified. In total, 63.34 mg of polyphenols and 20.36 mg of flavonoids were detected. Lipid peroxidation IC50 values were 212, 38, 56, and 365 g/mL for DPPH, ABTS, and superoxide radicals. Reducing power of the plant material showed the maximum absorbance of 0.56 in 500 µg/mL concentration. Furthermore, the plant extract quenched cadmium telluride quantum dots fluorescence in a dose dependent manner. The results from quenching concluded that Croton bonplandianum with QDs might be used as a drug targeting and delivery nanomaterial.


Asunto(s)
Croton , Quercetina , Quercetina/análisis , Croton/química , Quempferoles/análisis , Flavonoides/análisis , Polifenoles/análisis , Espectrometría de Masas , Antioxidantes/farmacología , Cromatografía Liquida , Extractos Vegetales/química , Cromatografía Líquida de Alta Presión , Hojas de la Planta/química
14.
Chemosphere ; 310: 136826, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36243087

RESUMEN

This study aimed to carry out the bioaugmentation of crude oil/motor oil contaminated soil. The mixture of novel strains Pseudomonas aeruginosa PP3 and Pseudomonas aeruginosa PP4 were used in this bioaugmentation studies. The four different bioaugmentation systems (BS 1-4) were carried out in this experiment labelled as BS 1 (Crude oil contaminated soil), BS 2 (BS 1 + bacterial consortia), BS 3 (Motor oil sludge contaminated soil), and BS 4 (BS 3 + bacterial consortia). The total petroleum hydrocarbon (TPH) was investigated for monitor the effectiveness of bioaugmentation process. The highest TPH removal rate was recorded on BS 4 (9091 mg Kg -1) was about 67% followed by 52% on BS 2 (8584 mg Kg -1) respectively. The percentage of biodegradation efficiency (BE) of residual crude and motor oil contaminated soil were evaluated by GCMS analysis and the results showed that 65% (BS 2) and 83% (BS 4) respectively. Further the bioaugmented soil was subjected to the plant cultivation (Lablab purpureus) and the results revealed that the L. purpureus was rapidly grown in the systems BS 4 and BS 2 than the system BS 1 and BS 2 which was due to the lesser biodegradation of the crude oil contents. In resultant, it can be concluded that the soil was suitable for the cultivation of plant. Overall, this study revealed that the selected bacterial consortia were effectively degraded the hydrocarbon and act as a potential bioremediator in the hydrocarbon polluted soil in a short period.


Asunto(s)
Petróleo , Contaminantes del Suelo , Petróleo/metabolismo , Suelo/química , Pseudomonas/metabolismo , Contaminantes del Suelo/análisis , Microbiología del Suelo , Hidrocarburos/metabolismo , Biodegradación Ambiental , Bacterias/metabolismo
15.
Microbiol Res ; 265: 127184, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36115172

RESUMEN

Hydrocarbon contamination is continuing to be a serious environmental problem because of their toxicity. Hydrocarbon components have been known to be carcinogens and neurotoxic organic pollutants. The physical and chemical methods of petroleum removal have become ineffective and also are very costly. Therefore, bioremediation is considered the promising technology for the treatment of these contaminated sites since it is cost-effective and will lead to complete mineralization.The current study also concentrates on bioremediation of petroleum products by bacterium isolated from petroleum hydrocarbon contaminated soil. The current work shows that bacterial strains obtained from a petroleum hydrocarbon contaminated environment may degrade petroleum compounds. Two strains Bacillus licheniformis ARMP2 and Pseudomonas aeruginosa ARMP8 were identified as petroleum-degrading bacteria of the isolated bacterial colonies. The best growth conditions for the ARMP2 strain were determined to be pH 9, temperature 29 °C with sodium nitrate as its nitrogen source, whereas for the ARMP8 strain the optimal growth was found at pH 7, temperature 39 °C, and ammonium chloride as the nitrogen source. Both strains were shown to be effective at degrading petroleum chemicals confirmed by GCMS. Overall petroleum product degradation efficiency of the strains ARMP2 and ARMP8 was about 88 % and 73 % respectively in 48 h.The strains Bacillus licheniformis ARMP2 and Pseudomonas aeruginosa ARMP8 were shown to be effective at degrading petroleum compounds in the current study. Even greater results might be obtained if the organisms were utilised in consortia or the degradation time period was extended.


Asunto(s)
Petróleo , Contaminantes del Suelo , Cloruro de Amonio/metabolismo , Bacterias/metabolismo , Biodegradación Ambiental , Carcinógenos/metabolismo , Hidrocarburos/metabolismo , Hidrocarburos/toxicidad , Nitrógeno/metabolismo , Petróleo/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Suelo/química , Microbiología del Suelo , Contaminantes del Suelo/metabolismo
16.
Chemosphere ; 299: 134366, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35318014

RESUMEN

This Paper describes the synthesis of nickel doped ZnO is planned by chemical co-precipitation techniques. The prepared nanostructured nickel doped zinc oxide samples were analyzed by thermogravimetric differential thermal analysis (TG/DTA), X-ray diffraction (XRD), Fourier transform infra red (FTIR), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), electron paramagnetic resonance (EPR), and cyclic voltametry (CV). Nanostructure nickel doped ZnO materials have developed as promising for the basis of its broad range of employing in diverse areas. The attractive properties of nickel doped ZnO materials are highly demanded in high-energy potential applications. The nickel doped zinc oxide materials are hexagonal wurtzite arrangement is confirmed by XRD. The morphological -features of FE-SEM show nickel doped zinc oxide NPs are the structure of spherical type with agglomeration. The calculated particle size 11 nm is confirmed by HR-TEM. EPR spectra of nickel doped zinc oxide nanoparticles are ferromagnetic nature. Further, CV studies of Ni doped ZnO materials of the specific capacitance value is 133 Fg-1 at the scan rate 10 mVs-1 it is suitable for super capacitor application. The quantum chemical calculations were done by using DFT techniques through B3LYP/LANL2DZ level of basis set.

17.
Environ Pollut ; 304: 119223, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35351596

RESUMEN

Crude oil contaminant is one of the major problem to environment and its removal process considered as most challenging tool currently across the world. In this degradation study, crude oil hydrocarbons are degraded on various pH optimization conditions (pH 2, 4,6,7,8 and 10) by using two biosurfactant producing bacterial strains Pseudomonas aeruginosa PP3 and Pseudomonas aeruginosa PP4. During crude oil biodegradation, degradative enzymes alkane hydroxylase and alcohol dehydrogenase were examined and found to be higher in PP4 than PP3. Biodegradation efficiency (BE) of crude oil by both PP3 and PP4 were analysed by gas chromatography mass spectroscopy (GCMS). Based on strain PP3, the highest BE was observed in pH 2 and pH 4 were found to be 62% and 69% than pH 6, 7, 8 and 10 (47%, 47%, 49% and 45%). It reveals that PP3 was survived effectively in acidic condition and utilized the crude oil hydrocarbons. In contrast, the highest BE of PP4 was observed in pH 7 (78%) than pH4 (68%) and pH's 2, 6, 8 and 10 (52%, 52%, 43% and 53%) respectively. FTIR spectra results revealed that the presence of different functional group of hydrocarbons (OH, -CH3, CO, C-H) in crude oil. GCMS results confirmed that both strains PP3 and PP4 were survived in acidic condition and utilized the crude oil hydrocarbons as sole carbon sources. This is the first observation on biodegradation of crude oil by the novel strains of Pseudomonas aeruginosa in acidic condition with higher BE. Overall, the extracellular enzymes and surface active compounds (biosurfactant) produced by bacterial strains were played a key role in crude oil biodegradation process.


Asunto(s)
Petróleo , Bacterias/metabolismo , Biodegradación Ambiental , Hidrocarburos/metabolismo , Petróleo/metabolismo , Pseudomonas aeruginosa/metabolismo , Tensoactivos/metabolismo
18.
Bioprocess Biosyst Eng ; 45(3): 493-501, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34981182

RESUMEN

A simple, cost effective and eco-friendly silver nanoparticle (AgNPs) was synthesized by wild edible Macrolepiota mushroom. Nanoparticles were characterized by UV-visible, FTIR, XRD analysis and TEM analysis. The characterized studies confirmed the spherical shape of AgNPs with 20-50 nm size. Biocorrosion efficacy of myco-synthesized AgNPs and the mushroom extract were tested against mild steel by corrosive bacteria Bacillus thuringiensis EN2, Terribacillus aidingensis EN3 and Bacillus oleronius EN9. Weight loss analysis, EIS, and surface analysis were used to evaluate the corrosion inhibition efficiency of mild steel in various experimental systems. Reduced corrosion rate (0.07 mm/y, 0.14 mm/y), reduced weight loss (0.006 ± 2, 0.011 ± 2) and increased corrosion inhibition efficiency (59%, 18%) were identified in both system II and system IV. Peak intensity was reduced in both surface analysis studies (FTIR and XRD) in the presence of mushroom extract and AgNPs. EIS studies reveal that the mushroom extract and AgNPs act as a corrosive green inhibitor and adsorbs on the mild steel surfaces in cooling water tower system, which are responsible for corrosion protection.


Asunto(s)
Agaricales , Cáusticos , Nanopartículas del Metal , Extractos Vegetales/farmacología , Plata/farmacología , Acero , Agua
19.
Chemosphere ; 292: 133413, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34973253

RESUMEN

PAHs are organic pollutants that have carcinogenic and mutagenic impacts on human health and are a subject of great concern. The soil-bound polycyclic aromatic hydrocarbons (PAHs) in the urban areas can be very lethal to human health. The concentrations, sources, and possible cancer risks of 15 PAHs were analysed by collecting roadside soil samples in Lucknow, India. The range of ∑15PAHs was found to be 478.94 ng/g to 8164.07 ng/g with a mean concentration of 3748.23 ng/g. The highest contribution (32.5%) was found to be from four-ring PAHs, followed by six-ring (24.5%) and five-ring (16.7%) PAHs. The source apportionment through diagnostic ratios ANT/(ANT + PHE) against FL-2/(FL-2+PYR) highlighted the dominance of petroleum, wood, coal, and grass combustion as sources of PAHs in the study area. Source apportionment was also done through positive matrix factorization, confirming the dominance of 'vehicular emissions' (49%), followed by 'coal and biomass combustion' (∼39%), and 'leakages, volatilization and petroleum combustion' (∼12%) as potential sources. The results from lifetime cancer risks (ILCR) varied in the range of 7.5 × 10-4 and 1.3 × 10 × -2 illustrating 'high cancer risk'. The total cancer risk susceptibility of children was found to be 31% more than that of adults. The highest risk associated with toxic equivalent concentration (TEQ) was found at site S8 highlighting the impact of the presence of an international airport, and huge traffic load. The present study will prove to be useful for information related to human exposure to PAHs content in soil in the study area and as baseline study for policy makers, stakeholders, and researchers.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Adulto , Carcinógenos/análisis , Carcinógenos/toxicidad , Niño , China , Carbón Mineral/análisis , Monitoreo del Ambiente , Humanos , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad
20.
Environ Res ; 204(Pt A): 112029, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34509486

RESUMEN

Pb(II) is a heavy metal that is a prominent contaminant in water contamination. Among the different pollution removal strategies, adsorption was determined to be the most effective. The adsorbent and its type determine the adsorption process's efficiency. As part of this effort, a magnetic reduced graphene oxide-based inverse spinel nickel ferrite (rGNF) nanocomposite for Pb(II) removal is synthesized, and the optimal values of the independent process variables (like initial concentration, pH, residence time, temperature, and adsorbent dosage) to achieve maximum removal efficiency are investigated using conventional response surface methodology (RSM) and artificial neural networks (ANN). The results indicate that the initial concentration, adsorbent dose, residence time, pH, and process temperature are set to 15 mg/L, 0.55 g/L, 100 min, 5, and 30 °C, respectively, the maximum removal efficiency (99.8%) can be obtained. Using the interactive effects of process variables findings, the adsorption surface mechanism was examined in relation to process factors. A data-driven quadratic equation is derived based on the ANOVA, and its predictions are compared with ANN predictions to evaluate the predictive capabilities of both approaches. The R2 values of RSM and ANN predictions are 0.979 and 0.991 respectively and confirm the superiority of the ANN approach.


Asunto(s)
Nanocompuestos , Contaminantes Químicos del Agua , Adsorción , Óxido de Aluminio , Compuestos Férricos , Grafito , Cinética , Plomo , Óxido de Magnesio , Níquel , Contaminantes Químicos del Agua/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA