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1.
Chemosphere ; 336: 139203, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37315851

RESUMEN

Life on earth is dependent on clean water, which is crucial for survival. Water supplies are getting contaminated due to the growing human population and its associated industrialization, urbanization, and chemically improved agriculture. Currently, a large number of people struggle to find clean drinking water, a problem that is particularly serious in developing countries. To meet the enormous demand of clean water around the world, there is an urgent need of advanced technologies and materials that are affordable, easy to use, thermally efficient, portable, environmentally benign, and chemically durable. Physical, chemical and biological methods are used to eliminate insoluble materials and soluble pollutants from wastewater. In addition to cost, each treatment carries its limitations in terms of effectiveness, productivity, environmental effect, sludge generation, pre-treatment demands, operating difficulties, and the creation of potentially hazardous byproducts. To overcome the problems of traditional methods, porous polymers have distinguished themselves as practical and efficient materials for the treatment of wastewater because of their distinctive characteristics such as large surface area, chemical versatility, biodegradability, and biocompatibility. This study overviews improvement in manufacturing methods and the sustainable usage of porous polymers for wastewater treatment and explicitly discusses the efficiency of advanced porous polymeric materials for the removal of emerging pollutants viz. pesticides, dyes, and pharmaceuticals whereby adsorption and photocatalytic degradation are considered to be among the most promising methods for their effective removal. Porous polymers are considered excellent adsorbents for the mitigation of these pollutants as they are cost-effective and have greater porosities to facilitate penetration and adhesion of pollutants, thus enhance their adsorption functionality. Appropriately functionalized porous polymers can offer the potential to eliminate hazardous chemicals and making water useful for a variety of purposes thus, numerous types of porous polymers have been selected, discussed and compared especially in terms of their efficiencies against specific pollutants. The study also sheds light on numerous challenges faced by porous polymers in the removal of contaminants, their solutions and some associated toxicity issues.


Asunto(s)
Contaminantes Ambientales , Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Humanos , Aguas Residuales , Porosidad , Adsorción , Colorantes , Polímeros , Purificación del Agua/métodos , Preparaciones Farmacéuticas , Contaminantes Químicos del Agua/análisis
2.
Heliyon ; 9(5): e15912, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37206034

RESUMEN

Jam Quality is a factor robustly influenced by storage conditions. The current research aimed to develop papaya jam with improved nutritional attributes, rheological profile, and shelf-life utilizing date pit powder as a functional ingredient. The effect of date pit powder on the formulated product's physicochemical, microbial, and organoleptic properties was analyzed. Results revealed that overall mineral profile (0.35-1.11%), crude fiber (0.56-2.01%), pH (3.51-3.70%), and antioxidant properties (22.97-30.67%) were significantly increased while water activity reduced (0.77-0.73). Moreover, date pit powder improved the color scores like a*(10.10-10.67), b* (8.13-8.78), L* (25.56-28.09), and textural attributes (Cohesiveness: 0.83-0.90; Firmness: 6.82-6.93) of functional papaya jam. Microbial count reduced from 3.60 × 105-3.06 × 105 cfu/ml by adding date pit powder and staying within the acceptable limit (4.13 × 105-3.60 × 105 cfu/ml) during 2-month storage at refrigeration. Organoleptic evaluation depicted that samples treated with date pit powder scored better than the control, and a sample with 75% pectin replacement was considered best.

3.
ACS Omega ; 7(18): 15809-15820, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35571809

RESUMEN

The current study comprises the successful synthesis of a Ni-WO3@g-C3N4 composite as an efficient and recoverable nanocatalyst for oxidative desulfurization of both model and real fuel oils. The physiochemical characterization of the synthesized composite was confirmed via Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy, and thermogravimetric analysis. SEM results showed that Ni-WO3 particles were well-decorated on the g-C3N4 surface with an interesting morphology as appeared on the surface like spherical particles. The obtained findings revealed that 97% dibenzothiophene (DBT) removal can be achieved under optimized conditions (0.1 g of the catalyst, 1 mL of an oxidant, 100 mg/L DBT-based model fuel, a time duration of 180 min, and a temperature of 40 °C). Additionally, the catalytic activity for real fuel was also investigated in which 89.5 and 91.2% removal efficiencies were achieved for diesel and kerosene, respectively, as well as fuel properties following ASTM specifications. A pseudo first-order kinetic model was followed well for this reaction system, and the negative value of ΔG was due to the spontaneous process. Additionally, the desulfurization study was optimized via a response surface methodology (RSM/Box-Behnken design) for predicting optimum removal of sulfur species by drawing three-dimensional RSM surface plots. The Ni-WO3@g-C3N4 proved to be a promising catalyst for desulfurization of fuel oil by exhibiting reusability of five times with no momentous decrease in efficiency.

4.
Sci Rep ; 12(1): 7362, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35513408

RESUMEN

The present study encompasses the application of cost effective, organo-modified bentonite material for efficient desulfurization of model oil and real fuel. For the adsorptive desulfurization of oil, dibenzothiophene (DBT) was used as model compound. Various experimental parameters (time, temperature, adsorbent-amount and DBT concentration) were thoroughly investigated. The synthesized material was characterized via X-ray diffraction (XRD), X-ray Fluorescence (XRF), Scanning electron microscopy (SEM), Energy dispersive x-ray (EDX), Thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). The modification exhibits the increase in interlayer spacing of clay as confirmed from XRD and modified material shows interesting morphology as compared to unmodified bentonite. The results showed that > 90% of DBT removal was achieved under optimized conditions for B-BTC, B-BTB and B-DSS and > 80% for B-BEHA, for model fuel oil which are greater than unmodified clay (< 45%). Additionally, the findings from desulfurization of real fuel oil declare that 96.76% and 95.83% removal efficiency was achieved for kerosene and diesel oil respectively, at optimized conditions and fuel properties follow ASTM specifications. The obtained findings well fitted with thermodynamic, isothermal (Langmuir) with adsorption capacity (70.8 (B-BTC), 66 (B-BTB), 61.2 (B-DSS) and 55.2 (B-BEHA) in mg/g) and pseudo-second-order kinetics. In thermodynamic studies, negative sign ([Formula: see text] specifies the spontaneity whereas, [Formula: see text] endothermic and positive sign [Formula: see text] show randomness after DBT adsorption onto organoclay.

5.
Environ Res ; 212(Pt A): 113160, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35351451

RESUMEN

For the first time, two new kinds of inorganic-organic hybrid nanomaterials (Bi2WO6@rGO and Cu-WO4@rGO) were fabricated by simple hydrothermal treatment and employed for green and efficient oxidative desulfurization of real fuel. The characterization of newly synthesized nanocomposites was performed by SEM, EDX, P-XRD, FT-IR and TGA. SEM and XRD analyses revealed well decoration of dopants (Cu-WO4 and Bi-WO3) on the surface of rGO with a crystallite size of <50 nm. The catalytic activity of both nanocatalysts was examined for model (dibenzothiophene) and real fuel (kerosene and diesel) by oxidative desulfurization route. Experimental findings revealed a high efficiency of over 90% under optimal reaction conditions of 0.1 g catalyst, 1 mL of oxidant, and 100 mg/L after 120 min at 30 °C. The major factors affecting desulfurization efficiency (time, temperature, catalyst amount, dibenzothiophene (DBT) concentration and amount of oxidant) and kinetic studies were described. The DBT removal via oxidative desulfurization followed pseudo first-order kinetics with an activation energy of 14.57 and 16.91 kJ/mol for Cu-WO4@rGO and Bi2WO6@rGO, respectively. The prepared catalysts showed promising reusability for the ODS process up to 5 times with no significant decrease in efficiency. In conclusion, the findings confirm the robustness of newly prepared nanocomposite for efficient production of sulfur-free oil.


Asunto(s)
Aceites Combustibles , Nanocompuestos , Grafito , Cinética , Oxidantes , Estrés Oxidativo , Espectroscopía Infrarroja por Transformada de Fourier
6.
Chemosphere ; 293: 133538, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34998849

RESUMEN

Increasing demand of food and agriculture is leading us towards the increasing use and introduction of pesticides to the environment. The upright increase of pesticides in water and associated adverse effects have become a great point of concern to develop proficient methods for their mitigation from water. Various different methods have been traditionally employed for this purpose. Recently, nanotechnology has turned out to be the field of prodigious interest for this purpose, and various specific methods were developed and employed to remove pesticides from water. In this study, nanotechnological methods such as adsorption and degradation have been thoroughly discussed along with their applications and limitations where different types of nanoparticles, nanocomposites, nanotubes, and nanomembranes have played a vital role. However, in this study the most commonly adopted method of adsorption is considered to be the better technique due to its low cost, efficiency, and ease of operation. The adsorption kinetic models were described to explain the efficiency of the nano-adrsorbants in order to evaluate the mass transfer processes. However, various degradation methodologies including photocatalysis and catalytic reduction have also been elaborated. Numerous robust metal, metal oxide and functionalized magnetic nanomaterials have been emphasized, categorized, and compared for the removal of pesticides from water. Additionally, current challenges faced by researchers and future directions have also been provided.


Asunto(s)
Contaminantes Ambientales , Nanocompuestos , Plaguicidas , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Nanotecnología , Contaminantes Químicos del Agua/toxicidad
7.
RSC Adv ; 10(32): 19041-19058, 2020 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-35518289

RESUMEN

Conversion of nitroaniline (NA), a highly toxic pollutant that has been released into aquatic systems due to unmanaged industrial development in recent years, into the less harmful or a useful counterpart is the need of the hour. Various methods for its conversion and removal have been explored. Owing to its nominal features of advanced effectiveness, the chemical reduction of 4-NA using various different nanocatalytic systems is one such approach that has attracted tremendous interest over the past few years. The academic literature has been confined to case studies involving silver (Ag) and gold (Au) nanoparticles, as these are the two most widely used materials for the synthesis of nanocatalytic assemblies. Focus has also been given to sodium borohydride (NaBH4), which is used as a reductant during the chemical reduction of NA. This systematic review summarizes the fundamentals associated with the catalytic degradation of 4-NA, and presents a comprehensive and critical study of the latest modifications used in the synthesis of these catalytic systems. In addition, the kinetics, mechanisms, thermodynamics, as well as the future directions required for understanding this model reaction, have been provided in this particular study.

8.
Nat Prod Res ; 34(9): 1311-1314, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-30618269

RESUMEN

Volatile oil composition of leaves and fruits of Terminalia arjuna (Roxb.) was reported for the first time. Oils were extracted by microwave assisted hydrodistillation where yield of both oils were found to be 0.20% and their GC-MS analyses led to the identification of 65 and 48 constituents, respectively. Major constituents of leaves were carvacrol (11.17%), thymol (6.52%), α-terpinyl acetate (5.92%) and anethole (5.13%) while that of fruits were (E)-isoeugenol (11.48%), furfural (8.25%), p-vinylguaiacol (6.8%) and p-ethylguaiacol (5.72%) that demonstrated a significant difference between composition of its aerial parts, however, 33 constituents were identical that showed similarity characteristics in quality of these oils. Both leaf and fruit oils were found active against pathogenic and drug-resistant microbes: E. coli, Methicillin-resistant S. aureus, P. aeruginosa, Total-drug-resistant P. aeruginosa and K. pneumoniae with MIC values of 0.32, 0.32, 0.64, 0.64, 2.56 mg/mL and 0.16, 0.16, 0.32, 0.64, 1.28 mg/mL, respectively.


Asunto(s)
Antibacterianos/farmacología , Aceites Volátiles/análisis , Terminalia/química , Antibacterianos/análisis , Cimenos/análisis , Farmacorresistencia Bacteriana/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Klebsiella pneumoniae/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Componentes Aéreos de las Plantas/química , Hojas de la Planta , Pseudomonas aeruginosa/efectos de los fármacos , Terpenos/análisis , Timol/análisis
9.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1126-1127: 121708, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31437773

RESUMEN

Analysis of acidic pharmaceuticals in complex biological samples is a challenging and formidable task due to the existence of interfering constituents within the sample matrices. Therefore, in order to avoid analytical column clogging and suppression/enhancement of signals of the analyte of interest, herein a simple, cost-effective and quick online ion chromatography based clean-up setup was introduced. This system was further coupled with a cost-effective homemade photochemically induced fluorimetric (PIF) setup for direct online conversion of non-fluorescent acidic pharmaceutical drugs into their respective fluorescent species. This advantageous system was favorably applied for the determination of four non-fluorescent acidic compounds in two complex biological samples (human serum and oral fluid) with minimum labor and organic solvent consumption. At optimized conditions, the developed method has shown good sensitivity, selectivity, satisfactory recoveries (88.68-102.14%) and low limits of detection (0.35-8.10 µg/L) with minimum or zero matrix effect.


Asunto(s)
Cromatografía por Intercambio Iónico/métodos , Fluorometría/métodos , Preparaciones Farmacéuticas/análisis , Ácidos/análisis , Ácidos/sangre , Ácidos/química , Colorantes Fluorescentes/química , Humanos , Límite de Detección , Modelos Lineales , Preparaciones Farmacéuticas/sangre , Preparaciones Farmacéuticas/química , Reproducibilidad de los Resultados , Saliva/química
10.
Crit Rev Anal Chem ; 49(6): 534-541, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30739482

RESUMEN

Water contamination is a worldwide critical issue for the present society to avoid competition and maintain an environmentally friendly scenario. Removal of various pollutants including inorganic and organic compounds from water is a big challenge nowadays. Worldwide attention to promote polluted water and technologies related to its treatment has been adversely increased. The utilization of metal/metal oxide nanoparticles (NPs) for this purpose has gained much attention due to its exceptional properties imparted by reduced size and effective surface area. Moreover, metal/metal oxide NPs-based innovation for improved expulsion productivity is an ingenious area for research and development but the use of such NPs presents some serious risks. Herein, the advanced requisition of NPs for polluted water treatment is highlighted along with the difficulties related to them and their toxic impacts when used as water purifiers. Additionally, the plausible fate of metal/metal oxide NPs incorporated in the water for purification and salient future challenges are deliberated.


Asunto(s)
Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Metales/química , Óxidos/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Contaminantes Químicos del Agua/toxicidad
11.
Sci Prog ; 100(3): 299-312, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28779759

RESUMEN

In this review, various methods of preparation of activated carbon from agricultural and commercial waste material are reviewed. In addition, we also discuss various activation treatments using a comparative approach. The data are organised in tabulated form for ease of comparative study. A review of numerous characterisation techniques is also provided. The effect of time and temperature, activation conditions, carbonisation conditions and impregnation ratios are explained and several physical and chemical activation treatments of raw materials and their impact on the micro- and mesoporous volumes and surface area are discussed. Lastly, a review of adsorption mechanisms of activated carbon (AC) is also provided.

12.
Nat Prod Res ; 30(19): 2249-52, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26959311

RESUMEN

Morinda morindoides is an important Liberian traditional medicine for the treatment of malaria, fever, worms etc. The plant was subjected to integrated approaches including phytochemical screening and gas chromatography mass spectrometry (GC-MS) analyses. Phytochemical investigation of the powdered plant revealed the presence of phenolics, tannins, flavonoids, saponins, terpenes, steroidal compounds and volatile oil. Steam distillation followed by GC-MS resulted in the identification of 47 volatiles in its aerial parts: 28 were in common including various bioactive volatiles. Major constituents of leaves were phytol (43.63%), palmitic acid (8.55%) and geranyl linalool (6.95%) and stem were palmitic acid (14.95%), eicosane (9.67%) and phytol (9.31%), and hence, a significant difference in the percentage composition of aerial parts was observed. To study seasonal changes, similarity analysis was carried out by calculating correlation coefficient (r) and vector angle cosine (z) that were more than 0.91 for stem-to-stem and leaf-to-leaf batches indicating considerable consistency.


Asunto(s)
Morinda/química , Aceites Volátiles/análisis , Componentes Aéreos de las Plantas/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Fitoquímicos/análisis
13.
Int J Phytoremediation ; 18(5): 477-86, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26588059

RESUMEN

In the present study, microwave treated Salvadora oleoides (MW-SO) has been investigated as a potential biosorbent for the removal of toxic methyl violet dye. A batch adsorption method was experimented for biosorptive removal of toxic methyl violet dye from the aqueous solution. The effect of various operating variables, viz., adsorbent dosage, pH, contact time and temperature on the removal of the dye was studied and it was found that nearly 99% removal of the dye was possible under optimum conditions. Kinetic study revealed that a pseudo-second-order mechanism was predominant and the overall process of the dye adsorption involved more than one step. Hence, in order to investigate the rate determining step, intra-particle diffusion model was applied. Adsorption equilibrium study was made by analyzing Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) adsorption isotherm models and the biosorption data was found to be best represented by the Langmuir model. The biosorption efficiency of MW-SO was also compared with unmodified material, Salvadora oleoides (SO). It was found that the sorption capacity (qmax) increased from 58.5 mg/g to 219.7 mg/g on MW treatment. Determination of thermodynamic parameters such as free energy change (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°) confirmed the spontaneous, endothermic and feasible nature of the adsorption process. The preparation of MW-SO did not require any additional chemical treatment and a high percentage removal of methyl violet dye was obtained in much lesser time. Thus, it is in agreement with the principles of green chemistry. The results of the present research work suggest that MW-SO can be used as an environmentally friendly and economical alternative biosorbent for the removal of methyl violet dye from aqueous solutions.


Asunto(s)
Violeta de Genciana/metabolismo , Microondas , Salvadoraceae/metabolismo , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/métodos , Adsorción , Salvadoraceae/efectos de la radiación
14.
Artículo en Inglés | MEDLINE | ID: mdl-24082326

RESUMEN

This study was specifically designed to identify anticancer constituents in methanol-water extract of Polygonum bistorta L. and evaluate its cytotoxicity. For this purpose methanol-water (40:60 v/v) extract was subjected to conventional preparative high pressure liquid chromatography and 13 fractions were obtained. Constituents of obtained fractions were separated and identified with the help of GC-MS and LC-DAD-ESI-MS. Anticancer phenolic compounds such as gallic acid, protocatechuic acid, p-hydroxybenzoic acid, chlorogenic acid, vanillic acid, syringic acid, catechol, 4-methyl catechol, syringol and pyrogallol and fatty acids such as linoleic acid, myristic acid and palmitic acid were separated from different fractions. Fractions were evaluated for their cytotoxic activity on a rarely studied human hepatocellular carcinoma cell line (HCCLM3). 11 fractions showed good to strong cytotoxicity in a range of 200 µg/mL-800 µg/mL, whereas 2 fractions did not show any activity even at 800 µg/mL and no anticancer constituent was detected from them. 50 percent growth inhibition (GI50) values for five most active fractions were calculated and results were in a range of 86.5 (±3) µg/mL-126.8 (±3) µg/mL. 3 out of these 5 most active fractions were found to contain phenolic content in them whereas all other fractions containing phenolic content did possess cytotoxic activity that may suggest the importance of phenolic constituents in anticancer activity. Moreover, the results also showed a definite dose dependent relationship between amount of fractions and cytotoxic activity.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Fenoles/uso terapéutico , Fitoterapia , Extractos Vegetales/uso terapéutico , Polygonum/química , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Humanos , Fenoles/farmacología , Extractos Vegetales/farmacología
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