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1.
Int J Phytoremediation ; 25(13): 1830-1843, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37088874

RESUMEN

The present study was performed to assess Ni-immobilization and the phytoremediation potential of sunflower by the application of quinoa stalks biochar (QSB) and its magnetic nanocomposite (MQSB). The QSB and MQSB were characterized with FTIR, SEM, EDX, and XRD to get an insight of their surface properties. Three-week-old seedlings of sunflower were transplanted to soil spiked with Ni (0, 15, 30, 60, 90 mg kg-1), QSB and MQSB (0, 1, and 2%) in the wire house under natural conditions. The results showed that increasing Ni levels inhibited sunflower growth and yield due to the high production of reactive oxygen species (ROS) and lipid peroxidation. Enzyme activities like superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POX) also increased as Ni levels increased. However, the application of QSB and MQSB reduced Ni uptake, root-shoot, and shoot-seed translocation and decreased the generation of ROS, and lowered the activity of SOD, CAT, APX, and POX, leading to improved growth and yield, especially with MQSB. This was verified through SEM, EDX, XRD, and FTIR. It can be concluded that QSB and MQSB can effectively enhance Ni-tolerance in sunflowers and mitigate oxidative stress and human health risks.


The article focuses on enhancing the phytoremediation remediation potential of Helianthus annuus by using the quinoa stalks biochar (QSB) and magnetic quinoa stalks biochar (MQSB) by immobilization of Ni in soil and ultimately attenuation of oxidative stress in plants and human health risk. Iron enrichment of biochar improves the surface characteristics (surface area, functional groups, porosity, etc.) which help to immobilize metals ions. To the best of our knowledge, QSB and MQSB has never been used before to study the Ni dynamics and for enhancing sunflower phytoremediation potential.


Asunto(s)
Chenopodium quinoa , Helianthus , Contaminantes del Suelo , Humanos , Níquel/farmacología , Helianthus/metabolismo , Especies Reactivas de Oxígeno/farmacología , Chenopodium quinoa/metabolismo , Hierro , Biodegradación Ambiental , Estrés Oxidativo , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/farmacología , Contaminantes del Suelo/análisis , Antioxidantes/metabolismo , Antioxidantes/farmacología
2.
Heliyon ; 9(3): e14451, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36950602

RESUMEN

The construction and building industry in the modern world heavily relies on advanced techniques and materials such as polymers. However, with the world's population alarmingly increasing, contributing to the greenhouse effect, and severe weather conditions amplifying, it has become crucial to reduce the heat effects in both new and old buildings. To achieve this, 50-70% more energy is necessary, which highlights the importance of energy-efficient construction practices and materials. Consequently, a comprehensive study was conducted to evaluate the efficacy of Polyurethane in indoor environments and energy conservation. Current study was performed due to an innovative application of insulation materials as to reduce the heat and energy costs in construction works. Thermal conductivity at mean temperature 35 °C was found 0.0272 (W/m K) with maximum in burnt clay brick (1.43 W/m K) by using hotplate apparatus. Specific heat was also found less 0.85 (KJ/Kg K) at density 32 kg/m3 while results were at par in reinforcement cement concrete and burnt clay brick 0.91, 0.91 (KJ/Kg K) respectively. Similarly, heat transmittance values of different roof sections by using polyurethane insulation showing satisfaction the ECBC in Buildings deviating standard U-value 1.20% to 0.418 (W/m2 K) with its excellent performance. Polyurethane treatments have been found to exert a significant impact on the computation of thermal resistance and overall heat transfer coefficients. In contrast, non-insulated treatments yielded inconclusive results with little to no significance. This highlights the importance of insulation materials in energy-efficient construction practices. Energy consumption in winter and summer also has shown the significant impact by using polyurethane application with cumulative saving of 60-62% electricity. Economic Benefit of polyurethane in RCC and Conventional buildings describes positive and highly significant impact in present study. Application of polyurethane in new and old buildings ultimate enhanced the better quality of life and living standards from people of applied countries and is strongly recommended for future prospects and endeavors as Eco-friendly and energy efficient for sustainable development.

3.
Environ Sci Pollut Res Int ; 30(44): 99202-99218, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35768713

RESUMEN

Land surface temperature (LST) is defined as a phenomenon which shows that microclimate of an urban system gets heated much faster than its surrounding rural climates. The expansion of buildings has a noteworthy influence on land use/land cover (LULC) due to conversion of vegetation land into commercial and residential areas and their associated infrastructure by which LST is accelerated. The objective of the research was to study the impact of changes in LULC on LST of Southern Punjab (Pakistan) through remote sensing (RS) data. Landsat images of 30-year duration (1987, 1997, 2007 and 2017) were employed for identifying vegetation indices and LST in the study region. These images also helped to work out normalized difference water index (NDWI) and normalized difference built-up index (NDBI) maps. There was an increase from 29620 (3.63 %) to 88038 ha (10.8 %) in built-up area over the 30 years. LST values were found in the range 12-42 °C, 11-44 °C, 11-45 °C and 11-47 °C in the years 1987, 1997, 2007 and 2017, respectively. Regression coefficients (R2) 0.81, 0.78, 0.84 and 0.76 were observed between NDVI and LST in the corresponding years respectively. Our study showed that NDVI and NDWI were negatively correlated with less LST; however, NDBI showed positive correlation with high LST. Our study gives critical information of LULC and LST and will be a helpful tool for policy makers for developing effective policies in managing land resources.


Asunto(s)
Tecnología de Sensores Remotos , Urbanización , Temperatura , Pakistán , Monitoreo del Ambiente/métodos
4.
Environ Sci Pollut Res Int ; 30(44): 99247-99259, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36279057

RESUMEN

Nickel (Ni) is an essential element for plants; however, excessive uptake of Ni causes phytotoxicity in plants. The phytotoxic effects of Ni on the growth of quinoa and the underlaying mechanisms for Ni tolerance and phytoremediation are unknown. Hence, the present study investigated Ni tolerance and accumulation potential of two quinoa genotypes (Puno and Vikinga). Both genotypes were exposed to Ni (0, 100, 200, 300, and 400 µM) in half-strength Hoagland nutrient solution for three weeks. Results revealed that shoot and root lengths, biomass, stomatal conductance, and chlorophyll contents were decreased with the increase of Ni concentration. Excessive uptake of Ni resulted in the limited uptake of K by root and its translocation to shoot. Ni caused oxidative stress in plants by overproduction of H2O2 leading to lipid peroxidation of cell membranes. Genotype Puno showed greater tolerance to Ni than Vikinga based on tolerance index, lower bioconcentration factor, and translocation factor. Greater tolerance of Puno was mainly attributed to improved physiological responses and amelioration of oxidative stress by induction of antioxidant enzymes such as peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX). It was revealed through multivariate analysis that Ni had strong negative correlations with growth and physiological attributes and positive associations with oxidative stress attributes. The study demonstrated genotypic variation in response to varying Ni concentrations and Puno performed better than Vikinga for phytostabilization of Ni-contaminated soils.


Asunto(s)
Chenopodium quinoa , Níquel , Níquel/metabolismo , Chenopodium quinoa/genética , Chenopodium quinoa/metabolismo , Biodegradación Ambiental , Peróxido de Hidrógeno/metabolismo , Antioxidantes/metabolismo , Genotipo
6.
Erwerbsobstbau (Berl) ; : 1-10, 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38625261

RESUMEN

Mass loss from fresh produce is linked to a reduction of its aesthetic value. However, a relationship between mass loss and biochemical quality parameters at different storage conditions has not been widely explored. Therefore, the current study is designed with the objectives to determine the behavior of fruit quality parameters and a relationship between fruit mass loss and fruit quality at two different storage conditions. Sweet orange fruit stored in a zero energy cool chamber (ZECC) had greater shelf-life of more than 15 days, fruit size (62.40 mm) and peel (35.15%) and lower mass loss (4.94%), juice (32.19%) and electrical conductivity (EC) (2.06 S/m) as compared to ambient conditions in laboratory during 25 days of storage. In ZECC, only EC was positively correlated (r = 0.57) with mass loss, whereas at room temperature EC (r = 0.76), total soluble solids (TSS) (r = 0.60) and fruit internal temperature (r = 0.64) were positively and peel (%) (r = -0.52) and fruit diameter (r = -0.49) were negatively correlated with mass loss. Correlation of combined storage conditions revealed that EC (r = 0.47) and TSS (r = 0.50) were positively and peel (%) (r = -0.77) and fruit diameter (r = -0.55) were negatively correlated with mass loss (%). The principal component analysis (PCA) revealed that the scores of room temperature were strongly associated with TSS, pH, EC, mass loss (%), juice (%) and internal temperature (°C), whereas scores of ZECC were strongly associated with pulp (%), ascorbic acid (mg 100 mL-1), acidity (%), and fruit diameter (mm).

7.
Sci Rep ; 12(1): 13210, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35915211

RESUMEN

Timely and accurate estimation of rice-growing areas and forecasting of production can provide crucial information for governments, planners, and decision-makers in formulating policies. While there exists studies focusing on paddy rice mapping, only few have compared multi-scale datasets performance in rice classification. Furthermore, rice mapping of large geographical areas with sufficient accuracy for planning purposes has been a challenge in Pakistan, but recent advancements in Google Earth Engine make it possible to analyze spatial and temporal variations within these areas. The study was carried out over southern Punjab (Pakistan)-a region with 380,400 hectares devoted to rice production in year 2020. Previous studies support the individual capabilities of Sentinel-2, Landsat-8, and Moderate Resolution Imaging Spectroradiometer (MODIS) for paddy rice classification. However, to our knowledge, no study has compared the efficiencies of these three datasets in rice crop classification. Thus, this study primarily focuses on comparing these satellites' data by estimating their potential in rice crop classification using accuracy assessment methods and area estimation. The overall accuracies were found to be 96% for Sentinel-2, 91.7% for Landsat-8, and 82.6% for MODIS. The F1-Scores for derived rice class were 83.8%, 75.5%, and 65.5% for Sentinel-2, Landsat-8, and MODIS, respectively. The rice estimated area corresponded relatively well with the crop statistics report provided by the Department of Agriculture, Punjab, with a mean percentage difference of less than 20% for Sentinel-2 and MODIS and 33% for Landsat-8. The outcomes of this study highlight three points; (a) Rice mapping accuracy improves with increase in spatial resolution, (b) Sentinel-2 efficiently differentiated individual farm level paddy fields while Landsat-8 was not able to do so, and lastly (c) Increase in rice cultivated area was observed using satellite images compared to the government provided statistics.


Asunto(s)
Oryza , Agricultura , Pakistán , Imágenes Satelitales
8.
Environ Geochem Health ; 44(1): 257-272, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33907913

RESUMEN

Salinity and lead (Pb) contamination of soil are important environmental issues. A hydroponics experiment was performed to unravel the effects of salinity on modulation of Pb tolerance and phytoremediation potential of quinoa. Four-week-old plants of quinoa genotype "Puno" were treated with different concentrations of NaCl (0, 150 and 300 mM), Pb (0, 250 and 500 µM) and their combinations. It was noticed that plant biomass, chlorophyll contents and stomatal conductance of quinoa were slightly affected at 150 mM NaCl or 250 µM Pb. However, the higher concentrations of NaCl (300 mM) and Pb (500 µM) caused significant decline in these attributes. The accumulation of Na in quinoa increased under the combined application of salt with highest level of Pb. The uptake of K was not affected at the lower levels of either salinity or Pb, but decreased significantly at their highest levels. The combination of salinity and Pb increased H2O2 contents and caused lipid peroxidation that was mitigated by the activation of antioxidant enzymes (superoxide dismutase, catalase, peroxidase, ascorbate peroxidase). The activities of these enzymes increased by 4-, 3.75-, 5.4- and 2-fold, respectively, in the combined application of 500 µM Pb and 300 mM NaCl with respect to control. A multivariate analysis indicated that Pb tolerance potential of quinoa under combined application of NaCl and Pb was higher at 150 than 300 mM NaCl. The bioconcentration factor and translocation factor for Pb remained less than one either in the absence or presence of salinity. Lead accumulation and tolerance potential indicated that quinoa genotype "Puno" is suitable for phytostabilization of Pb under saline conditions.


Asunto(s)
Chenopodium quinoa , Contaminantes del Suelo , Biodegradación Ambiental , Peróxido de Hidrógeno , Plomo/toxicidad , Salinidad , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad
9.
Environ Geochem Health ; 44(6): 1827-1839, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34524606

RESUMEN

Plant redox homeostasis governs the uptake, toxicity and tolerance mechanism of toxic trace elements and thereby elucidates the remediation potential of a plant. Moreover, plant toxicity/tolerance mechanisms control the trace element compartmentation in edible and non-edible plant organs as well as the associated health hazards. Therefore, it is imperative to unravel the cellular mechanism involved in trace element toxicity and tolerance. The present study investigated the toxicity and tolerance/detoxification mechanisms of four levels of arsenic (As(III): 0, 5, 25 and 125 µM) in Brassica oleracea under hydroponic cultivation. Increasing As levels significantly decreased the pigment contents (up to 68%) of B. oleracea. Plants under As stress showed an increase in H2O2 contents (up to 32%) in roots while a decrease (up to 72%) in leaves because As is mostly retained in plant roots, while less is translocated toward the shoot, as evident from the literature. Arsenic treatments caused lipid peroxidation both in the root and leaf cells. Against As-induced oxidative stress, B. oleracea plants mediated an increase in the activities of peroxidase and catalase. Contradictory, the ascorbate peroxidase and superoxide dismutase activities slightly decreased in the As-stressed plants. In conclusion and as evident from the literature data analysis, As exposure (especially high level, 125 µM) caused pigment toxicity and oxidative burst in B. oleracea. The ability of B. oleracea to tolerate As-induced toxicity greatly varied with applied treatment levels (As-125 being more toxic than lower levels), plant organ type (more toxicity in leaves than roots) and physiological response parameter (pigment contents more sensitive than other response variables). Moreover, the multivariate statistical analysis appeared to be a useful method to estimate plant response under stress and trace significant trends in the data set.


Asunto(s)
Arsénico , Brassica , Contaminantes del Suelo , Oligoelementos , Antioxidantes/metabolismo , Arsénico/análisis , Arsénico/toxicidad , Brassica/metabolismo , Análisis de Datos , Peróxido de Hidrógeno , Estrés Oxidativo , Hojas de la Planta/química , Raíces de Plantas/metabolismo , Plantas/metabolismo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Oligoelementos/análisis
10.
Environ Sci Pollut Res Int ; 27(32): 39852-39864, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32696407

RESUMEN

The presence of toxic substances in aquifers, particularly potentially toxic heavy metals, is an important environmental and social concern worldwide. These heavy metals are capable to exert many injurious health effects in human beings by intake of drinking metal-contaminated water. However, very little attention is paid towards quantitative and qualitative analysis of groundwater used for drinking purpose in several less-developed countries. Therefore, this study was intended to estimate, for the first time, the heavy metal levels in groundwater/drinking water in District Vehari, Pakistan. A total of 129 groundwater samples were obtained and subjected to analyze heavy metal concentrations (lead, copper, cadmium, nickel, manganese, chromium, iron, and zinc). Moreover, pH, electrical conductivity, temperature, total dissolved solids, and anion (carbonates, chloride, and bicarbonates) and cation (calcium, potassium, sodium, lithium, and barium) contents of groundwater were also determined. It was noticed that the values of several groundwater physicochemical characteristics such as cation contents, alkalinity, chloride concentration, and especially the concentrations of heavy metals such as Pb (93%), Cd (68%), and Fe (100%) were higher than their limit values given by WHO. Principal component analysis separately grouped heavy metals and physicochemical characteristics of groundwater. The risk assessment indices predicted potential carcinogenic risks due to the consumption of metal-rich groundwater, predominantly with Cd (0.0007-0.03). The mean hazard quotient (HQ) values for all the metals were < 1, while Pb showed HQ > 1 envisaging non-carcinogenic risk with the consumption of studied groundwater. The findings of the study emphasized on the need of appropriate approaches to remediate groundwater before being used for drinking purpose.


Asunto(s)
Agua Potable , Agua Subterránea , Metales Pesados , Contaminantes Químicos del Agua , Agua Potable/análisis , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Pakistán , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
11.
Pak J Pharm Sci ; 33(5(Special)): 2413-2416, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33832883

RESUMEN

The study aims to prepare reliable, ecofriendly and cost efficient zinc nanoparticles (Zn NPs) by Mentha piperita L. leaf extract and zinc sulfate heptahydrate, for four pathogenic bacteria. Synthesized NPs were investigated by using X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Zeta Potential. Disc diffusion method was used to check their antibacterial activity. For synthesizing Zn NPs leaf extract was used as a biological reducing agent. During reaction, appearance of cloudy white solution due to reduction in the number of zinc ions, indicated the Zn NPs formation. XRD determined the average NPs size i.e. 9.8 nm. FTIR confirmed the presence of functional groups in the leaf extract sample. Spherical shape of the NPs was confirmed by the SEM analysis. Antibacterial activity of the Zn NPs was measured by the inhibition zones against various bacteria (E. coli, P. aeruginosa, S. aureus and S. pneumoniae). Inhibition zones were observed in the range of 2.9 to 12.9 mm.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Mentha piperita , Extractos Vegetales/farmacología , Sulfato de Zinc/química , Antibacterianos/aislamiento & purificación , Bacterias/crecimiento & desarrollo , Pruebas Antimicrobianas de Difusión por Disco , Composición de Medicamentos , Mentha piperita/química , Nanopartículas , Nanotecnología , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta
12.
J Photochem Photobiol B ; 192: 147-157, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30738346

RESUMEN

Synthesis of nanoparticles (NPs) through "green" chemistry is an exciting area of research with wide applications. Trianthema portulacastrum's extract containing greater amount of reducing agents has been explored first time for the synthesis of ZnO-NPs that characterized with UV/Vis, XRD, FT-IR, SEM,EDX, HR-TEM and XPS. The particles of ZnO-NPs are crystalline and having the size in the range of 25-90 nm. The cell viability of ZnO-NPs was studied using Mouse pre-osteoblast cell line MC3T3-E1 sub-clone 14 cells which confirmed its biocompatibility that render for biomedical applications. The antibacterial properties were evaluated against Staphylococcus aureus and Escherichia coli which showed high potency of synthesized ZnO-NPs against these species. The antifungal activities of ZnO-NPs were screened against Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus of fungal species. The antioxidant activity of the as-synthesized NPs was also studied using DPPH (2, 2-diphenyl-1-picrylhydrazyl) substrate. The ZnO-NPs were evaluated for catalytic activity through degradation of Synozol Navy Blue-KBF textile dye using solar irradiation that causes 91% degradation of the dye in 159 min. Mechanistic pathways for the degradation of Synozol Navy Blue-KBF dye using ZnO-NPs were also proposed from the pattern of the degradation of the dye and the resulting by-products. The results concluded that the ZnO-NPs synthesized by green method have high biological and photocatalytic applications.


Asunto(s)
Aizoaceae/química , Tecnología Química Verde/métodos , Nanopartículas del Metal/química , Extractos Vegetales/química , Animales , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antifúngicos/aislamiento & purificación , Antifúngicos/farmacología , Catálisis , Línea Celular , Colorantes/química , Restauración y Remediación Ambiental/métodos , Ratones , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Óxido de Zinc/química
13.
J Photochem Photobiol B ; 173: 150-164, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28582711

RESUMEN

Synthesis of Nobel metal nanoparticles, play a key role in the field of medicine. Plants contain a substantial number of organic constituents, like phenolic compounds and various types of glycosides that help in synthesis of metal nanoparticles. Synthesis of metal nanoparticles by green method is one of the best and environment friendly methods. The major significance of the green synthesis is lack of toxic by-products produced during metal nanoparticle synthesis. The nanoparticles, synthesized by green method show various significant biological activities. Most of the research articles report the synthesized nanoparticles to be active against gram positive and gram negative bacteria. Some of these bacteria include Escherichia coli, Bacillus subtilis, Klebsiella pneumonia and Pseudomonas fluorescens. The synthesized nanoparticles also show significant antifungal activity against Trichophyton simii, Trichophyton mentagrophytes and Trichophyton rubrum as well as different types of cancer cells such as breast cancer cell line. They also exhibit significant antioxidant activity. The activities of these Nobel metal nano-particles mainly depend on the size and shape. The particles of small size with large surface area show good activity in the field of medicine. The synthesized nanoparticles are also active against leishmanial diseases. This research article explores in detail the green synthesis of the nanoparticles and their uses thereof.


Asunto(s)
Tecnología Química Verde , Nanopartículas del Metal/química , Apoptosis/efectos de los fármacos , Espectroscopía de Resonancia por Spin del Electrón , Eritrocitos/citología , Eritrocitos/efectos de los fármacos , Eritrocitos/metabolismo , Glicósidos/química , Oro/química , Oro/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Células HeLa , Hemólisis/efectos de los fármacos , Humanos , Células MCF-7 , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Fenoles/química , Plata/química , Plata/farmacología , Trichophyton/efectos de los fármacos
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