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1.
Sci Total Environ ; 923: 171406, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38432361

RESUMO

Global climate change has significantly impacted the production of various crops, particularly long-term fruit-bearing plants such as citrus. This study analyzed the fruit quality of 12 citrus orchards (Citrus Sinensis L.Osbeck cv. Bingtang) in a subtropical region in Yunnan, China from 2014 to 2022. The results indicated that high rainfall (>220 mm) and low cumulative temperature (<3150 °C) promoted increases in titratable acidity (>1.8 %) in young fruits. As the fruits further expanded (with a horizontal diameter increasing from 50 to 65 mm), excessive rainfall (300-400 mm), lower cumulative temperature (<2400 °C), and a reduced diurnal temperature range (<10 °C) hindered decreases in titratable acidity. Conversely, low rainfall (<220 mm), high cumulative temperature (>3150 °C), and a high diurnal temperature range (>14 °C) promoted the accumulation of soluble solids in young fruits (9 %) at 120 days after flowering (DAF). Furthermore, low rainfall (<100 mm) favored the accumulation of soluble solids (1.5 %) during fruit expansion (195-225DAF). To quantify the relationship between fruit acidity and climate variables at 120 DAF, we developed a regression model, which was further validated by actual measurements and accurately predicted fruit acidity in 2023. Our findings have the potential to assist citrus growers in optimizing cultivation techniques for the production of high-quality citrus under increasingly variable climatic conditions.


Assuntos
Citrus sinensis , Citrus , Mudança Climática , China , Temperatura Baixa , Frutas
2.
Int J Phytoremediation ; 24(14): 1465-1474, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35156484

RESUMO

This study aims to examine the heavy metal phytofiltration potential of Hydrocotyle umbellata from Nullah Lai wastewater and its environmental risk. Wastewater was initially analyzed for heavy metals and physicochemical parameters and compared with irrigation water standards. The phytofiltration potential of H. umbellata was determined by periodically monitoring heavy metal concentrations at time points T1 (day 05), T2 (day10), T3 (day 15), and T4 (day 20). This study shows that some water parameters reached the permissible limits after treatment with H. umbellata. Results of the risk analysis reveal a significant discharge (kg d-y) of heavy metals to arable land. Phytofiltration efficiency of H. umbellata for water quality parameters was in order of Ni (98.75%), Cr (98.11%), Cd (95.84%), Pb (94.90%), Cu (94.10%), Zn (85.34%), BOD (53.67%), TDS (29.28%), EC (27.31%), Cl (6.65%), and SAR (6.34%). The growth of H. umbellata in wastewater resulted in heavy metal bioaccumulation in both roots and shoots of the plant. Less than 01 translocation factor (TF) values for cadmium, copper, lead, chromium, and zinc showed the metal tolerance ability of the tested plant. These results demonstrated that treated water could be used in water-deficient peri-urban areas as supplementary irrigation.


This study evaluates the phytofiltration potential of Hydrocotyle umbellata for heavy metals (Cu, Cr, Cd, Pb, Ni, and Zn) from Nullah Lai wastewater by greenhouse experiments. The environmental risk associated with using Nullah Lai wastewater for irrigation purposes was estimated.


Assuntos
Centella , Metais Pesados , Poluentes do Solo , Águas Residuárias/análise , Biodegradação Ambiental , Metais Pesados/análise , Qualidade da Água , Plantas , Monitoramento Ambiental , Poluentes do Solo/análise
3.
Mol Biol Rep ; 47(7): 5051-5060, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32524390

RESUMO

Nowadays, lower post-release survivorship of hatchery-reared fish in natural aquatic bodies has attained great attention and research is in progress to determine the reasons for their higher mortality. It is assumed that hatchery rearing environments negatively affect the physiological stress response of the fish. Thus, understanding how rearing environments modulate this is important for the well-being of fish. Here, an attempt has been made to assess the influence of two early rearing environments, i.e., barren (BR), mimic the conventional hatchery rearing environment; without any substrate and enrichment items and structurally enriched (ER), containing multi-colored gravel substrate, cobbles and plants, on the stress regulators i.e., HPI-axis and brain monoaminergic system of fish. Three-day old grass carp (Ctenopharyngodon idella) postlarvae were reared up to the fingerling stage in the aforementioned environments. For the stress assay, fish were subjected to net capture followed by 30 min confinement in a small container at a lower water level. The pre- and post-stress responses were compared by evaluating their water-borne cortisol and the mRNA level of corticotropin releasing hormone (CRH), dopamine D1A receptor (DRD1A) and hydroxytryptamine receptor 2B (HTR2B) in the whole brain through qPCR analysis. Results of two-way ANOVA revealed significantly low (p < .001) post-stress concentration and release rate of water-borne cortisol and pre- and post-stress expression of CRH, DRD1A and HTR2B genes in the ER than BR fish. It is concluded that a structurally complex early rearing environment reduces the stress level in fish.


Assuntos
Carpas/genética , Proteínas de Peixes/genética , Hidrocortisona/metabolismo , Estresse Fisiológico , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Carpas/crescimento & desenvolvimento , Carpas/metabolismo , Hormônio Liberador da Corticotropina/genética , Hormônio Liberador da Corticotropina/metabolismo , Meio Ambiente , Proteínas de Peixes/metabolismo , Receptor 5-HT2B de Serotonina/genética , Receptor 5-HT2B de Serotonina/metabolismo , Receptores de Dopamina D1/genética , Receptores de Dopamina D1/metabolismo
4.
J Therm Biol ; 89: 102570, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32364999

RESUMO

The ability of a species and population to respond to a decrease or an increase in temperature depends on their adaptive potential. Here, the critical thermal tolerance (CTmax and CTmin) of four populations: Labeo rohita, Catla catla, and their reciprocal hybrids L. rohitaâ™€× C. catla♂ (RC) and C. catla♀ × L. rohita♂ (CR) being acclimatized at four acclimation temperatures (22, 26, 30 and 34 °C) were determined. All populations indicated substantial variations (P < 0.05) in CTmax and CTmin values. L. rohita displayed, comparatively the highest CTmax with largest total and intrinsic polygon zones as well as the upper and lower acquired thermal tolerance zones followed by RC and CR hybrids, while C. catla showed significantly the highest CTmin value and the smallest intrinsic and acquired thermal tolerance zones. Both hybrids illustrated low parent heterosis (≤11%). Additionally, the highest expression of Hsp70 and Hsp90 (heat shock proteins) genes, serum lysozyme level, respiratory burst activity and lowest lipid peroxidation level under lower and higher temperature shock further illustrated strong physiological mechanism of L. rohita in contrast to C. catla, to deal with acute temperature, while hybrids, especially F1 RC hybrid appeared as a good option to replace C. catla in relatively higher and lower temperature areas.


Assuntos
Cipriniformes/genética , Proteínas de Peixes/genética , Proteínas de Choque Térmico/genética , Resposta ao Choque Térmico , Hibridização Genética , Animais , Cipriniformes/imunologia , Cipriniformes/metabolismo , Feminino , Proteínas de Peixes/metabolismo , Proteínas de Choque Térmico/metabolismo , Vigor Híbrido , Peroxidação de Lipídeos , Masculino , Muramidase/sangue
5.
Int J Phytoremediation ; 22(7): 725-732, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31916455

RESUMO

Contamination of pre-urban arable land, by untreated municipal/industrial effluents derived heavy metals, is causing serious health hazards to human beings and abiotic components of the ecosystem. In this study, phytoremedial potential of four non-eatable floriculture plants, i.e. antirrhinum, pansy, calendula, and marigold, was explored by growing in heavy metal contaminated soil (collected from pre-urban area under untreated wastewater irrigation for more than 20 years) amended with bacterial inoculum and EDTA amended soils under greenhouse conditions for 75 days. Bacterial inoculation gave a maximum increase in the root (47.1%) and shoot (30.9%) biomass, while EDTA amendment gave 37.1 and 21.4%, respectively. However, EDTA application increases more metal concentrations in the root (65%) and shoot (36%) than that of bacterial inoculum, i.e. 37 and 27%, respectively. The values of bioconcentration factor (BCF) of all the plants for Cd, Cr, Ni and Pb were significantly increased by EDTA application and bacterial inoculum over control. The BCF values were either ≈1 or >1 in all the treatments in case of Cr. Ni and Pb. Contrarily, reduction in translocation factor (TF) values of all the flowering plants for all the metals were observed over control when the growth medium was treated with EDTA and bacterial inoculum.


Assuntos
Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Ecossistema , Horticultura , Humanos , Solo
6.
Fish Shellfish Immunol ; 95: 464-472, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31698070

RESUMO

Encapsulated probiotic administration can be a nutritional strategy to improve the growth performance and immune status of fish. Here commercial application of encapsulated G. candidum was evaluated as a feed supplement to fingerlings of L. rohita reared in earthen ponds under semi-intensive culture conditions. Fingerlings with an average body weight of 20 ±â€¯2.34 g were distributed randomly in three groups and experiment was conducted in triplicate. The control group (P0) was fed 35% protein basal diet while the two treated groups, P1 and P2 were fed basal diet supplemented with 109 CFU g-1 un-encapsulated (free) and encapsulated G. candidum, respectively, for eleven weeks. Results indicated significantly (P < 0.05) improved growth rate, intestinal enzyme activities (protease, amylase and cellulase) and hemato-immunological indices (RBCs, Hb, HCT, WBCs, MCHC, respiratory bursts and phagocytic activity, total protein, lysozyme, IgM), upregulation of heat shock protein HSP 70 gene in muscle, intestine and liver tissues and reduction of serum AST and ALT activities, total cholesterol and triglyceride in fish fed G. candidum supplemented diets (P1 and P2 groups) as compared to basal diet (P0 group). However, diet supplemented with encapsulated G. candidum showed the most significant (p < 0.001) positive effect in comparison to un-encapsulated probiotic. In conclusion, a pronounced effect of G. candidum especially in the encapsulated form on the growth, health status and immunity of L. rohita reared in semi intensive culture system, suggesting its application as a feed additive in practical/commercial semi-intensive earthen pond culture system.


Assuntos
Ração Animal , Cyprinidae/crescimento & desenvolvimento , Cyprinidae/imunologia , Suplementos Nutricionais , Geotrichum , Probióticos/administração & dosagem , Animais , Aquicultura/métodos , Imunidade Inata
7.
Bull Environ Contam Toxicol ; 103(6): 865-870, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31637447

RESUMO

Arsenic (As) concentrations in fine (2) and coarse (3) rice varieties belonging to Hafizabad, Gujranwala and Sheikhupura districts was assessed initially by means of field survey, followed by pot experiments. Bulk soil samples collected from same rice districts (Hafizabad and Gujtanwala) were spiked with As (0, 10, 20 mg kg-1) and each was amended with iron sulphate (0, 25, 50 g kg-1) to investigate their effect on plant growth and uptake under anaerobic conditions. Survey results revealed that mainly fine long grain (Super Basmati and KSK 515) and coarse long grain (Basmati 386 and Kainat) rice varieties were grown in the area. Overall, 16% rice grain samples were above the recommended permissible limit (RPL) of 300 mg kg-1. Among varieties, 24% grain samples of coarse and 12% of fine varieties had As concentration above the RPL. Results of pot experiments showed a significant decrease in straw and grain yield and increase in As concentration with increasing rates of As spiking. Paddy yield increased significantly when As spiked soils were amended with iron sulfate; and opposite was true for As concentration.


Assuntos
Arsênio/análise , Produção Agrícola/métodos , Recuperação e Remediação Ambiental/métodos , Compostos Ferrosos/química , Oryza/química , Poluentes do Solo/análise , Anaerobiose , Clima Desértico , Grão Comestível/química , Grão Comestível/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Paquistão , Solo/química
8.
Int J Phytoremediation ; 21(8): 799-806, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30773895

RESUMO

Heavy metals phytoextraction potential of swollen duckweed (Lemna gibba Linn.) and lesser duckweed (Lemna aequinoctialis Welw.) was determined under greenhouse conditions by exposing to untreated industrial/municipal effluent for a period of 21 days. The nickel (Ni), lead (Pb), and cadmium (Cd) concentrations in water samples were measured weekly and in plant biomass at the termination of experiments. Significant differences (p < 0.05) between initial and final physicochemical parameters and in heavy metal concentrations of plant and water samples were observed. Periodically measured metal concentrations in mediums revealed that removal percentage was dependent on initial Ni (2.15 mg L-1), Pb (1.51 mg L-1), and Cd (0.74 mg L-1) concentrations. The final metal removal percentages were in the sequence of Ni (97%) > Pb (94%) > Cd (90%) when treated with Lemna gibba L. as compared to control (9-12% reduction). High biomass production of Lemna gibba L. resulted in a large metal reduction in the growth medium and the total plant metal contents were in the sequence of Ni (427 µg) > Pb (293 µg) > Cd (105 µg). The lesser duckweed did not survive under experimental conditions. Based on these results, we concluded that Lemna gibba L. is a good candidate for phytoremediation of wastewater.


Assuntos
Cádmio , Metais Pesados/análise , Biodegradação Ambiental , Chumbo , Níquel
9.
Environ Monit Assess ; 190(5): 287, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29667025

RESUMO

Metal adsorption capacities of bioadsorbents, derived from low-cost agricultural waste, were assessed. Batch and column experiments were conducted for evaluation of lead (Pb), cadmium (Cd), and chromium (Cr) sorption kinetics on to modified (by treating with base and acid) and unmodified sugarcane bagasse and corn cob. Langmuir, Freundlich, and Redlich-Peterson equations were used to understand metal adsorption behavior and Elovich and Lagergren's pseudo-first-order and pseudo-second-order kinetics equations were used for estimation of adsorption kinetics parameter. The suitability of the models to experimental data was reflected by high r2 values. Among sorption models, Langmuir and Redlich-Peterson were proved equally good and Cd, Cr, and Pb adsorption process followed the Langmuir isotherm. Batch adsorption experiment showed that the metal adsorption ability of the treated materials was higher than that of untreated. The adsorption sequence was Pb > Cr > Cd. Pseudo-second-order kinetics model was found suitable in describing the obtained data. Result of the column adsorption experiments supplement the batch results and revealed the role of agricultural waste materials in remediation of heavy metal-polluted water.


Assuntos
Celulose/química , Metais Pesados/química , Modelos Químicos , Adsorção , Agricultura , Cádmio/análise , Cromo/análise , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Íons , Cinética , Metais Pesados/análise , Saccharum , Resíduos , Poluentes Químicos da Água/análise
10.
Environ Sci Pollut Res Int ; 25(13): 12570-12578, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29464606

RESUMO

Lead (Pb), chromium (Cr), and cadmium (Cd) removal capacity of sawdust (Picea smithiana) from aqueous solution was investigated by conducting batch experiments. Thermodynamic parameters, like change in standard free energy (ΔGΘ), enthalpy (ΔHΘ) and entropy (ΔSΘ) during bio-adsorption process were estimated using the Van't Hoff equation. The maximum metals adsorption was observed at pH 8, 20 g L-1 bio-adsorbent and at 60 min of contact time. The metal adsorption kinetics was examined by fitting the pseudo-first-order as well as four forms of pseudo-second-order kinetic models. Type 1 pseudo-second-order equation described adsorption kinetics better than others. Langmuir model and Freundlich equations were used for calculation of sorption parameters. The Langmuir maximum adsorption capacity of Pb, Cr, and Cd was 6.35, 3.37, and 2.87 mg g-1 at room temperature, respectively. The values of the separation factor (RL) were in between 0 and 1, indicating that bio-adsorption was favorable. Thermodynamics study revealed that the Pb, Cr, and Cd uptake reactions were endothermic and spontaneous. Results of the study asserted that the removal of heavy metal ions from aqueous solution is viable and the sawdust could be used in the treatment of effluents from industries, thereby reducing the level of water pollution.


Assuntos
Cádmio/análise , Cromo/análise , Chumbo/análise , Picea/química , Poluentes Químicos da Água/análise , Madeira/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Soluções , Termodinâmica
11.
Environ Monit Assess ; 189(11): 591, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29086096

RESUMO

The abilities of sorghum (Sorghum bicolor L.) and oat (Avena sativa L.) to take up heavy metals from soils amended with ethylenediaminetetraacetic acid (EDTA) were assessed under greenhouse conditions. Both plants were grown in two soils contaminated with heavy metals (Gujranwala-silty loam and Pacca-clay loam). The soils were treated with 0, 0.625, 1.25, and 2.5 mM EDTA kg-1 soil applied at both 45 and 60 days after sowing (DAS); the experiment was terminated at 75 DAS. Addition of EDTA significantly increased concentrations of Cd, Cr, and Pb in roots and shoots, and bio-concentration factors and phytoextraction rates were also increased. Post-harvest soil analysis showed that soluble fractions of metals were also increased significantly. The increase in Cd was ≈ 3-fold and Pb was ≈ 15-fold at the highest addition of EDTA in Gujranwala soil; in the Pacca soil, the increase was less. Similarly, other phytoremediation factors, such as metal translocation, bio-concentration factor, and phytoextraction, efficiency were also maximum when soils were treated with 2.5 mM EDTA kg-1 soil. The study demonstrated that sorghum was better than oat for phytoremediation.


Assuntos
Avena/fisiologia , Ácido Edético/química , Recuperação e Remediação Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Sorghum/fisiologia , Biodegradação Ambiental , Grão Comestível/química , Monitoramento Ambiental , Metais Pesados/química , Solo/química , Poluentes do Solo/química
12.
Int J Phytoremediation ; 19(12): 1077-1084, 2017 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-28678606

RESUMO

Municipal effluent of three rural settings of Islamabad was assessed for physicochemical and microbiological parameters by collecting wastewater from inlet and center of ponds. Results showed that water quality was comparatively better at the center as Typha latifolia plants were growing toward the center of ponds. In another study, the wastewater treatment ability of T. latifolia was investigated by growing them in industrial and municipal effluent under greenhouse conditions. Water and plant samples were collected periodically (3rd, 10th, 17th, 24th, and 31st day after transplanting) for the measurement of Pb, Cu, and Cd concentrations. A decrease in heavy metal concentration of both effluents was observed as the experiment progressed and metal removal percentages ranged between 81% and 96%. Complementary the increase in metal concentration in plant tissues was observed over experimental period. Among plant tissues, metal concentration of Pb was highest i.e. 362 mg kg-1 in roots and 313 mg kg-1 in shoots at end of experiment. Pb, Cu, and Cd concentrations were higher in roots than shoots and hence translocation factors were less than 1.0. Metal removal efficiency was better from industrial wastewater and was in order of Pb > Cu > Cd. T. latifolia can be used for remediation of heavy metal-polluted wastewater.


Assuntos
Esgotos , Typhaceae , Águas Residuárias , Biodegradação Ambiental , Metais Pesados/análise , Raízes de Plantas , Lagoas , Qualidade da Água
13.
Chemosphere ; 179: 112-119, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28364646

RESUMO

Chromium contamination of agronomic soil has to turn into a serious global problem. This research was pointed to assess the effects of three Cr-tolerant rhizobacteria (SS1, SS3, and SS6) on sunflower growth and heavy metal uptake under Cr smog i.e. 20, 30 and 40 ppm using K2Cr2O7. Root promotion assay and pot experiment were conducted to investigate and evaluate the effects of Cr tolerance rhizobacteria and Cr accumulation capacity of sunflower. From root promotion assay non-significant variation was observed in the root length between SS1 and SS3 compared with un-inoculated whereas SS6 enhanced the root length in the absence and presence of chromium. In addition, inoculation with rhizobacteria alleviated the Cr concentration and endorsed plant growth by enhancing Cr accumulation in sunflower. At different Cr levels, the Cr concentration in shoot was improved by each rhizobacterium though their difference was non-significant with each other, while the percentage increase was half as the Cr level doubled. Different rhizobacterium inoculation significantly (P < 0.05) affected the physiological and morphological characteristics of sunflower and increased the plant height, stem diameter, head diameter, grain yield, oil content of seeds, and total biomass, and among them, SS6 observed best followed by SS1 and SS3 comparing with un-inoculated. Our study illustrates an assessment about Cr-tolerant bacteria and their influences and recommends that these bacteria can effectively be used for crop improvement which provides a potential approach for Cr phytoremediation.


Assuntos
Biodegradação Ambiental , Cromo/farmacologia , Helianthus/crescimento & desenvolvimento , Metais Pesados/farmacocinética , Rhizobiaceae/fisiologia , Poluentes do Solo/análise , Biomassa , Cromo/análise , Tolerância a Medicamentos , Helianthus/microbiologia , Desenvolvimento Vegetal/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Microbiologia do Solo , Poluentes do Solo/farmacologia
14.
Int J Phytoremediation ; 18(1): 25-32, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26114480

RESUMO

Phytoremediation potential of L. minor for cadmium (Cd), copper (Cu), lead (Pb), and nickel (Ni) from two different types of effluent in raw form was evaluated in a glass house experiment using hydroponic studies for a period of 31 days. Heavy metals concentration in water and plant sample was analyzed at 3, 10, 17, 24, and 31 day. Removal efficiency, metal uptake and bio-concentration factor were also calculated. Effluents were initially analyzed for physical, chemical and microbiological parameters and results indicated that municipal effluent (ME) was highly contaminated in terms of nutrient and organic load than sewage mixed industrial effluent (SMIE). Results confirmed the accumulation of heavy metals within plant and subsequent decrease in the effluents. Removal efficiency was greater than 80% for all metals and maximum removal was observed for nickel (99%) from SMIE. Accumulation and uptake of lead in dry biomass was significantly higher than other metals. Bio-concentration factors were less than 1000 and maximum BCFs were found for copper (558) and lead (523.1) indicated that plant is a moderate accumulator of both metals. Overall, L. minor showed better performance from SMIE and was more effective in extracting lead than other metals.


Assuntos
Araceae/metabolismo , Metais Pesados/metabolismo , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Paquistão , Esgotos
15.
Environ Monit Assess ; 187(7): 470, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26116198

RESUMO

In this study, cadmium (Cd), chromium (Cr), and lead (Pb) adsorption potential of unmodified and modified sugarcane bagasse and ground wheat straw was explored from aqueous solution through batch equilibrium technique. Both the materials were chemically modified by treating with sodium hydroxide (NaOH) alone and in combination with nitric acid (HNO3) and sulfuric acid (H2SO4). Two kinetic models, pseudo-first order and pseudo-second order were used to follow the adsorption process and reaction fallowed the later model. The Pb removal by both the materials was highest and followed by Cr and Cd. The chemical treatment invariably increased the adsorption capacity and NaOH treatment proved more effective than others. Langmuir maximum sorption capacity (q m) of Pb was utmost (12.8-23.3 mg/g of sugarcane bagasse, 14.5-22.4 mg/g of wheat straw) and of Cd was least (1.5-2.2 mg/g of sugarcane bagasse, 2.5-3.8 mg/g of wheat straw). The q m was in the order of Pb > Cr > Cd for all the three adsorbents. Results demonstrate that agricultural waste materials used in this study could be used to remediate the heavy metal-polluted water.


Assuntos
Celulose , Metais Pesados/isolamento & purificação , Triticum , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Agricultura , Cádmio , Cromo , Monitoramento Ambiental , Cinética , Modelos Químicos , Saccharum , Resíduos , Purificação da Água
16.
Environ Monit Assess ; 187(2): 19, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25626568

RESUMO

The adsorption of cadmium (Cd), chromium (Cr), and lead (Pb), widely detected in wastewater, by unmodified and modified banana stalks, corn cob, and sunflower achene was explored. The three agricultural wastes were chemically modified with sodium hydroxide (NaOH), in combination with nitric acid (HNO3) and sulfuric acid (H2SO4), in order to improve their adsorptive binding capacity. The experiments were conducted as a function of contact time and initial metal ion concentrations. Of the three waste materials, corn cob had the highest adsorptive capacity for Pb than Cr and Cd. The NaOH-modified substrates had higher adsorptive capacity than the acid modified samples. The chemical treatment invariably increased the adsorption capacity between 10 and 100 %. The Langmuir maximum sorption capacity (q m) of Pb was highest (21-60 mg g(-1) of banana, 30-57 mg g(-1) of corn cob, and 23-28 mg g(-1) of sunflower achene) and that of Cd was least (4-7 mg g(-1) of banana, 14-20 mg g(-1) of corn cob, and 11-16 mg g(-1) of sunflower achene). The q m was in the order of Pb > Cr > Cd for all the three adsorbents. The results demonstrate that the agricultural waste materials used in this study could be used to remediate water polluted with heavy metals.


Assuntos
Agricultura , Metais Pesados/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Adsorção , Cádmio/análise , Cádmio/química , Cromo/análise , Cromo/química , Concentração de Íons de Hidrogênio , Chumbo/análise , Chumbo/química , Metais Pesados/química , Resíduos , Poluentes Químicos da Água/química
17.
Environ Monit Assess ; 186(6): 3957-68, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24515546

RESUMO

Natural and chemically enhanced phytoextraction potentials of maize (Zea mays L.) and sesbania (Sesbania aculeata Willd.) were explored by growing them on two soils contaminated with heavy metals. The soils, Gujranwala (fine, loamy, mixed, hyperthermic Udic Haplustalf) and Pacca (fine, mixed, hyperthermic Ustollic Camborthid), were amended with varying amounts of ethylenediaminetetraacetic acid (EDTA) chelating agent, at 0, 1.25, 2.5, and 5.0 mM kg(-1) soil to enhance metal solubility. The EDTA was applied in two split applications at 46 and 60 days after sowing (DAS). The plants were harvested at 75 DAS. Addition of EDTA significantly increased the lead (Pb) and cadmium (Cd) concentrations in roots and shoots, uptake, bioconcentration factor, and phytoextraction rate over the control. Furthermore, addition of EDTA also significantly increased the soluble fractions of Pb and Cd in soil over the controls; the maximum increase of Pb and Cd was 13.1-fold and 3.1-fold, respectively, with addition of 5.0 mM EDTA kg(-1)soil. Similarly, the maximum Pb and Cd root and shoot concentrations, translocation, bioconcentration, and phytoextraction efficiency were observed at 5.0 mM EDTA kg(-1) soil. The results suggest that both crops can successfully be used for phytoremediation of metal-contaminated calcareous soils.


Assuntos
Quelantes/química , Ácido Edético/química , Metais Pesados/metabolismo , Sesbania/fisiologia , Poluentes do Solo/metabolismo , Zea mays/fisiologia , Biodegradação Ambiental , Carbonato de Cálcio/química , Monitoramento Ambiental , Recuperação e Remediação Ambiental/métodos , Metais Pesados/análise , Metais Pesados/química , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/química
18.
Environ Monit Assess ; 185(3): 2503-15, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22832844

RESUMO

Water samples from selected locations of Nullah Lai and Koh-e-Noor textile mill in the metropolitan city of Rawalpindi and Islamabad, Pakistan, were collected. Physicochemical parameters and heavy metals were determined using standard analytical procedures in comparison with sites, locations and subsequent interval of 3 months. The results of the physicochemical analysis at different locations of Nullah Lai and Koh-e-Noor textile mill with an interval of 3 months were obtained in the following range: pH (7.16-8.29), temperature (17.8-28.8 °C), conductivity (1,005-3,347 µS/m), TDS (754.3-2,519.5 mg/L), turbidity (272.8-487.05 NTU), total hardness (300-452 mg/L), nitrates (10.11-22.95 ppm), calcium (74.31-139.2 ppm), chloride (127.72-396.16 ppm), sulphate (15.97-87.38 ppm), NaCl (210.5-631.1 ppm), Ni (0.30-0.72 ppm), Cd (0.005-0.03 ppm), Cr (0.2-7.4 ppm), Pb (0.12-0.73 ppm), Zn (0.03-0.08 ppm) and Cu (0.01-0.06 ppm). The highest value of physicochemical parameters (compared with Nullah Lai) was obtained in locations of Koh-e-Noor textile mill. The results obtained exceeded the maximum allowable limit set by the World Health Organization for drinking purpose but can be used for irrigation purposes after suitable treatment and purification.


Assuntos
Monitoramento Ambiental , Águas Residuárias/química , Poluentes Químicos da Água/análise , Metais Pesados/análise , Paquistão , Salinidade , Sulfatos/análise , Águas Residuárias/análise , Poluição Química da Água/estatística & dados numéricos
19.
Med Chem ; 8(6): 1190-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22741800

RESUMO

Two series of 2-adamantyl/adamantylmethyl-5-aryl-1,3,4-oxadiazoles (4a-l and 5a-l) were synthesized by cyclodehydration of adamantan-1-carboxylic acid/adamantylacetic acid with various aryl hydrazides (3a-l) in the presence of POCl(3). The synthesis was supported by spectroanalytical techniques and verified further by crystal structure determination of compounds 4e and 5k. The synthesized compounds were screened for their inhibitory activity against HIV-1 and HIV-2 in MT-4 cells. Compound 5b exhibited a moderate activity in vitro for the replication of both virus types, suggesting for further structural modification as a new lead in the development of an antiviral agent.


Assuntos
Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacologia , Oxidiazóis/síntese química , Oxidiazóis/farmacologia , Fármacos Anti-HIV/química , Técnicas de Química Sintética , Cristalografia por Raios X , HIV-1/efeitos dos fármacos , HIV-2/efeitos dos fármacos , Humanos , Modelos Moleculares , Conformação Molecular , Oxidiazóis/química
20.
Bull Environ Contam Toxicol ; 88(2): 204-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22020919

RESUMO

Metals in soils and vegetables irrigated with untreated municipal/industrial effluent, from four cities of Pakistan (Gujranwala, Sialkot, Hyderabad and Mirpurkhas) were assessed. The cadmium, copper, lead and chromium concentrations in the municipal/industrial effluent from all sites were above the recommended permissible limits. Similarly, cadmium, lead and nickel concentrations in almost all the soil samples were above the recommended permissible limits with chromium higher than the recommended permissible limits in 62% soils and copper higher in 26%. Cadmium and chromium concentrations were above the recommended permissible limits in all the examined vegetables and lead was exceeded in 90% of vegetables.


Assuntos
Irrigação Agrícola , Monitoramento Ambiental , Metais/análise , Poluentes do Solo/análise , Verduras/química , Eliminação de Resíduos Líquidos , Cidades , Humanos , Medição de Risco
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