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1.
Environ Sci Pollut Res Int ; 31(15): 22790-22801, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38413521

RESUMO

Arsenic is a highly toxic metal that causes cancer even at a low concentration and its removal from water resources is challenging. Herein, carbon extracted from waste onion bulbs is activated to cater for porosity and functionalized with magnetite (Fe3O4) nanoparticles (named MCK6) to address the challenge of As(III) removal. Synthesized MCK6 was highly mesoporous having a surface area of 208 m2/g, where magnetite nanoparticles (≤ 10 nm) are homogeneously distributed within a porous network. The developed adsorbent inherited functional groups from the biosource and magnetic property from magnetite making it ideal for removal of As(III). Further, MCK6 showed a maximum monolayer adsorption capacity (qm) of 10.2 mg/g at 298 K and pH 7. The adsorption thermodynamics delineates a non-spontaneous and endothermic reaction, where the kinetics followed pseudo 2nd order (R2 value of 0.977), while monolayer formation is explained by the Langmuir model. Moreover, MCK6 efficiently works to remove As(III) in a competitive metal ions system including Pb+2, Cd+2, and Ca+2, making it a suitable adsorbent to tackle contaminated water.


Assuntos
Nanopartículas de Magnetita , Poluentes Químicos da Água , Purificação da Água , Água/química , Óxido Ferroso-Férrico , Porosidade , Carbono , Poluentes Químicos da Água/análise , Adsorção , Cinética , Concentração de Íons de Hidrogênio , Nanopartículas de Magnetita/química
2.
Molecules ; 27(21)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36363976

RESUMO

In this work, graphene oxide (GO) and its reduced graphene oxide-zinc oxide nanocomposite (rGO-ZnO) was used for the removal of Cr (VI) from aqueous medium. By employing a variety of characterization techniques, morphological and structural properties of the adsorbents were determined. The adsorption study was done by varying concentration, temperature, pH, time, and amount of adsorbent. The results obtained confirmed that rGO-ZnO is a more economical and promising adsorbent for removing Cr (VI) as compared to GO. Kinetic study was also performed, which suggested that sorption of Cr (VI) follows the pseudo-first-order model. For equilibrium study, non-linear Langmuir was found a better fitted model than its linearized form. The maximum adsorption capacity calculated for GO and rGO-ZnO nanocomposite were 19.49 mg/g and 25.45 mg/g, respectively. Endothermic and spontaneous nature of adsorption was detected with positive values of ΔS (change in entropy), which reflects the structural changes happening at the liquid/solid interface.


Assuntos
Grafite , Poluentes Químicos da Água , Óxido de Zinco , Adsorção , Cromo/química , Poluentes Químicos da Água/química , Grafite/química , Cinética , Concentração de Íons de Hidrogênio
3.
Microsc Res Tech ; 85(7): 2497-2513, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35373868

RESUMO

The significance of grasses as fodder is enormous. However, it has been observed that different fodder grasses are identified locally with the similar vernacular names. Even same species recognized with different names. This happened due to their reduced and overlapped morphological characters. Hence comprehensive taxonomic keys were required to provide authentic identification of this grass flora. Current study established microscopic identification tools on the basis of leaf transverse anatomical features. Results demonstrated a great diversity in ribs and furrows arrangement among all studied grass members. Lolium temulentum, Phalaris minor, Poa annua, Arundo donax, Aristida adscensionis, Desmostachya bipinnata, Cenchrus biflorus and Digitaria ciliaris possessed ribs and furrows only at adaxial surfaces whereas all other species possessed this feature abaxially. Generally all the species contain three types of vascular bundles i.e. small, medium and large. Therefore, this qualitative feature is valuable only at family level, however, it found insignificant in taxa identification. Diversity was observed in bundle sheath type which could be taxonomically significant. Generally bundle sheath was found complete in most of species but in Bromus japonicus Thunb., Dactylis glomerata L., Acrachne racemosa (Heyne ex Roth) Ohwi, Chrysopogon aucheri (Boiss.) Stapf, Dichanthium annulatum (Forssk.) Stapf, Heteropogon contortus (L.) P Beauv. Ex. Roem & Schult. Eragrostis minor Host. and in Agrostis gigantea Roth. had incomplete type of sheath. Results reported great diversity in characters which could be taxonomically viable. RESEARCH HIGHLIGHTS: This research highlighted the significance of microscopic examination of leaf transverse anatomical features in field of taxonomy. Established anatomical tools would be of great importance for the identification of studied species.


Assuntos
Elétrons , Poaceae , Ração Animal , Microscopia Eletrônica de Varredura , Paquistão , Folhas de Planta/anatomia & histologia , Poaceae/anatomia & histologia
4.
PLoS One ; 17(2): e0263604, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35192648

RESUMO

Ethnobotanical field surveys were carried out in the Tanawal area of the Lesser Himalayan Region, Khyber Pakhtunkhawa, Province from April 2016 to October 2017. The area is located between 34.36 (34° 21' 30 N) latitude and 73.07 (73° 4' 0 E) longitude with an average elevation of 1374 meters above sea level. Ethnomedicinal data were collected through Participatory Rural Appraisal (PRA), and participants were selected through the snow-boll technique. Semi-structured, in-depth and open-ended interviews were conducted. The data were quantitatively evaluated using ethnomedicinal indices i.e. Relative frequency of citation (RFCs), Fidelity level (FL), and Use Value (UV). The ethnobotanical data were also comparatively analyzed through the Jaccard Index (JI). The study yielded 66 medicinal plants in 62 genera and 43 families. Asteraceae and Solanaceae were the most important families with five medicinal taxa each. Regarding medicinal plant part utilization, leaves (43.28%) were used predominantly, followed by whole plant (14.92%) and fruits (14.92%). Decoction was the main drug formulation applied to 21 species (31.15%) and the oral route was most common (56.1%) while 31.2% of medicinal plants were used for both oral and topical applications. Fifty health disorders were recorded and grouped in 15 categories. Maximum species were used to treat gastrointestinal disorders i.e. 13 species, dermal problems (12 species), and respiratory tract ailments (9). The calculated RFCs ranged between 81 to 31. The most important medicinal plants were Acacia modesta, Citrullus vulgaris, Tamarindus indica, and Momordica charantia with an RGFC of 81 each. The UV ranged between 0.58 and 3.6. Medicinal taxa with the highest UV were Dioscorea deltoidea (3.6), Withania coagulans (3.3), Momordica charantia (3.5), Silybum marianum and Pyrus pashia (3.2). FL values showed that 28 (41.79%) species had a FL value below 50 (74.62%) while 39 (58.20%) had higher FL values. Momordica charantia, Tamarindus indica, Acacia modesta and Citrullus vulgaris were 95.2 each. The Jaccard Index (JI) values ranged from16.77 to 0.98. The current study also reported 16 medicinal plants, commonly used around the globe, have been rarely documented for their medicinal values in the local ethnomedicinal literature i.e. Althaea officinalis, Plantanus orientalis, Jasminum sombac, Maytenus royleana, Cucurbita maxima, Phyllanthus emblica, Citrullus vulgaris. Polygonatum verticilliatum, Caseria tomentosa, Cistanche tubulosa, Bambusa arundinacea, Schinus molle, Tamarindus indica, Pongamia pinnata, Citrus limon and Catharanthus roseus. However, 48 medicinal plants had been reported in the literature but the current study reported their novel medicinal uses. Important taxa should be established in botanical gardens for in-situ conservation, chemical investigation and sustainable utilization. It would also be effective to improve the livelihoods of the local population.


Assuntos
Asteraceae/química , Etnobotânica/métodos , Fitoterapia/métodos , Extratos Vegetais/uso terapêutico , Solanaceae/química , Acacia/química , Asteraceae/classificação , Citrullus/química , Frutas/química , Humanos , Medicina Tradicional/métodos , Momordica charantia/química , Paquistão , Extratos Vegetais/química , Folhas de Planta/química , Plantas Medicinais/química , Solanaceae/classificação , Tamarindus/química
5.
Microsc Res Tech ; 85(5): 1703-1712, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34913538

RESUMO

This study highlighted the taxonomic utilization of palynological metaphors for selected members (53) of family Poaceae. Multiple microscopic technique light and scanning electrons had been employed for detailed analysis. Results reported monad pollen type in all studied 53 members, which showed its limited taxonomic value up to family level. In relation to shape of pollen both polar and equatorial views strikingly differed from each other. Like semi angular pollen observed in Dactyloctenium aegyptium (L.) Wild. whereas round-minutely irregular pollen in Lolium temulentum L. Polar and equatorial diameter also showed variation, that is, Desmostachya bipinnata (L.) Stapf. can be differentiated from Sorghum bicolor (L.) Moench on diameter variation basis. A pore characteristic does not show much qualitative variation; however pore sizes differ species to species. The most frequently scarbate sculpturing was observed in 28 species followed by verrucate. Hence it can be said that pollen shape, polar, and equatorial diameters, pore size, P/E ratio, pore sculpturing are of good taxonomic value and holds a significant position in identification and delimitation of Poaceae taxa.


Assuntos
Elétrons , Metáfora , Microscopia Eletrônica de Varredura , Poaceae , Pólen/ultraestrutura
6.
Pak J Pharm Sci ; 31(6 (Supplementary): 2655-2660, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30587475

RESUMO

During the present research, C. idella and C. auratus fish were exposed to 2 ppm concentration of imidacloprid for 28 and 24 days, respectively, and the effect on biochemical and haematological parameters was investigated. During the study of biochemical parameters, there occurred significant increase (P<0.05) in the serum levels of ALT and creatinine of imidacloprid exposed groups of both species of fish. The level of serum albumin of imidacloprid exposed groups of both fish species was significantly lower as compared to control group (P<0.05). Serum globulin level in imidacloprid exposed group of C. idella was insignificantly lower as compared to control group, however the serum globulin level of C. auratus was significantly lower than the control group (P < 0.05). The level of total proteins in serum of imidacloprid exposed groups of both fish species was insignificantly lower as compared to control groups (P>0.05). During the study of haematological parameters, TLC of C. idella was insignificantly (P>0.05) higher than control group but the TLC of C. auratus was significantly (P<0.05) higher than control. There was also observed increasing trend in the percentage of neutrophils and lymphocytes of imidacloprid exposed group of each fish species. The platelets count of imidacloprid exposed group of each fish species was significantly (P<0.05) lower than control group. The haemoglobin concentration of imidacloprid exposed group of C. idella was significantly lower than control group (P<0.05). In case of C. auratus, the haemoglobin level of imidacloprid exposed group was insignificantly lower than control group (P>0.05). From the finding of the present research it was concluded that 28 days exposure of C. idella and 24 days exposure of C. auratus to 2 ppm concentration of imidacloprid does not cause mortality however the exposure causes alteration in the normal level of biochemical and haematological parameters.


Assuntos
Carpas/sangue , Carpa Dourada/sangue , Inseticidas/administração & dosagem , Neonicotinoides/administração & dosagem , Nitrocompostos/administração & dosagem , Animais , Esquema de Medicação , Exposição Ambiental/efeitos adversos , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Fatores de Tempo
7.
Sci Rep ; 8(1): 13772, 2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30213989

RESUMO

We report a one-pot method for the preparation of graphene-cobalt hydroxide nanosheets (Co/G NSs) and their use as an effective elelctrocatalyst for water oxidation. Mechanical exfoliation of graphite via sonication produced graphene sheets, which were stabilized by the surface adsorption of a cationic surfactant (CTAB). In a subsequent step, varying amount of a cobalt complex [sodium hexanitrocobaltate(III)] was added which selectively bound with the positively charged head of surfactant. In the last step, cobalt complex was reduced with sodium borohydride to obtain Co/G NSs catalyst. The catalyst showed lower overpotential (280 mV) as compared to benchmark catalysts and decent stability and turnover frequency (TOF: 0.089 s-1) for oxygen evolution reaction (OER).

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