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1.
Environ Sci Pollut Res Int ; 31(29): 42277-42294, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38865046

RESUMO

Intercropping is a sustainable strategy recognized for boosting crop production and mitigating heavy metal toxicity in contaminated soils. This study investigates the effects of biochar amendments on Pb-contaminated soil, utilizing monocropping and intercropping techniques with C. olitorius and Z. mays. The research assesses Pb removal capacity, nutrient uptake, antioxidant enzymes, and soil Pb fractionation. In monocropping, the phytoremediation ratio for C. olitorius increased from 16.67 to 27.33%, while in intercropping, it rose from 19.00 to 28.33% with biochar amendments. Similarly, Z. mays exhibited an increased phytoremediation ratio from 53.33 to 74.67% in monocropping and from 63.00 to 78.67% in intercropping with biochar amendments. Intercropping significantly increased the peroxidase (POD) activity in Z. mays roots by 22.53%, and there were notable increases in shoot POD of C. olitorius (11.54%) and Z. mays (16.20%) with biochar application. CAT showed consistent improvements, increasing by 37.52% in C. olitorius roots and 74.49% in Z. mays roots with biochar. Biochar amendments significantly increased N content in soil under sole cropping of Z. mays and intercropping systems. In contrast, Cu content increased by 56.34%, 59.05%, and 79.80% in monocropping (C. olitorius and Z. mays) and intercropping systems, respectively. This suggests that biochar enhances nutrient availability, improving phytoremediation efficacy in Pb-contaminated soil. Phyto availability of trace metals (Zn, Mn, Cu, and Fe) exhibited higher levels with biochar amendments than those without. The findings indicate that intercropping and biochar amendments elevate antioxidant enzyme levels, reducing reactive oxygen species and mitigating Pb toxicity effects. This approach improves phytoremediation efficiency and holds promise for soil pollution remediation while enhancing nutrient content and crop quality in Pb-contaminated soil.


Assuntos
Biodegradação Ambiental , Carvão Vegetal , Corchorus , Chumbo , Poluentes do Solo , Solo , Zea mays , Carvão Vegetal/química , Solo/química , Metais Pesados
2.
ACS Omega ; 6(2): 1556-1567, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33490815

RESUMO

A CaO/clinoptilolite green nanocomposite (CaO/Clino) was synthesized by a green modification technique using calcium nitrate and green tea extract. The CaO/Clino nanocomposite promises a total basicity of 4.82 mmol OH/g, surface area of 252.4 m2/g, and ion exchange capacity of 134.3 mequiv/100 g, which qualifies the product as an effective catalyst in the transesterification of castor oil. The transesterification performance of the CaO/Clino catalyst was addressed statistically based on the response surface methodology and central composite rotatable design, considering the essential experimental parameters. Based on the interaction effect between the studied variables, the CaO/Clino catalyst can achieve an experimental biodiesel yield of 93.8% after 2.5 h at 120 °C with 3.5 wt % catalyst loading and 15:1 ethanol/castor oil molar ratio. The optimization function of the design suggested enhancement in the performance of the CaO/Clino catalyst to achieve a yield of 95.4% if the test time interval increased to 2.65 h and the ethanol content increased to 16:1 as a molar ratio to castor oil. The produced biodiesel over CaO/ClinO has acceptable technical qualifications according to the international requirements (EN 14214 and ASTM D-6751). The synthetic green CaO/Clino nanocomposite has better recyclability as a heterogeneous catalyst and higher activity than some investigated catalysts in literature.

3.
Nanotechnology ; 32(15): 155702, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33511967

RESUMO

The critical demand for eco-friendly, renewable, and safe energy resources is an essential issue encountered in the contemporary world. The catalytic transesterification of plant oils into biodiesel was assessed as promising a technique for providing new forms of clean and safe fuel. Natural clinoptilolite was doped with Na+ ions by green chemical reactions between sodium nitrite and green tea extract, producing a novel modified structure (Na+/Clino). The Na+/Clino product had an enhanced total basicity (6.41 mmol OH/g), ion exchange capacity (387 meq/100 g), and surface area (312.7 m2 g-1), which qualified it to be used as a potential basic catalyst for the transesterification of palm oil. Transesterification tests were statistically assessed using a response surface methodology and a central composite design. Considering the effect of how the significant factors interact with each other, the synthetic Na+/Clino achieved a 96.4% experimental biodiesel yield after 70 min at 100 °C in the presence of 2.75 wt% catalyst loading and a 12.5:1 methanol-to-palm-oil ratio. Based on the optimization function of the statistical model, the performance of Na+/Clino can theoretically be enhanced to increase the yield to 98.2% by expanding the test time to 85 min and the loading value to 3 wt%. The product yielded by the Na+/ClinO process is of adequate technical properties, considering the international levels for standard biodiesel (EN 14214 and ASTM D-6751). Finally, the prepared green Na+ doped clinoptilolite had excellent recyclability as a heterogeneous basic catalyst and displayed higher efficiency than several species of previously studied heterogeneous and homogenous catalysts.

4.
Braz. arch. biol. technol ; 64: e21210188, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1350268

RESUMO

Abstract Obesity results in detrimental effects on different body organs. Metformin (Met) has described to decrease the body weight of obese patient and to control the glucose level. This study aimed to evaluate the role of Met treatment for long period on the functionality of liver and kidney organs of obese rats. Forty rats were used in this study and divided into four groups as the following: group 1 (Gp1) was served as a negative control that administered orally with 200 µL of H2O. Gp2 of rats was administered with Met (200 mg/kg) daily for a month. Gp3 was obese rats, and Gp4 was obese rats administered with Met as in Gp2. All rats were sacrificed to analyze hematological, biochemical, and histopathological changes. The results showed that Met decreased the body weight of both naïve and obese rats, however, it caused hepato-renal dysfunctions in obese rats as evidenced by increased the levels of ALT, AST, urea, creatinine, and MDA and decrease in the antioxidants biomarkers (SOD, Cat and GSH). Collectively, Met causes liver and kidneys dysfunctions of obese rats and is not recommended to described for obese persons.

5.
Sci Rep ; 10(1): 14828, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908234

RESUMO

Novel MgO/CaO nanocomposite (MgO/CaO NRs) was synthesized by the hydrothermal method using diatomite porous frustules as a substrate under the microwave irradiation. The composite appeared as well crystalline rod-like nanoparticles with 52.3 nm as average particle size and 112.8 m2/g as BET surface area. The synthetic MgO/CaO NRs were addressed as a novel adsorbent for promising removal of levofloxacin (LVX) as pharmaceutical residuals. The adsorption studies revealed effective uptake of levofloxacin by MgO/CaO NRs with theoretical qmax of 106.7 mg/g and the equilibrium time of 720 min considering the best pH value (pH 7). The equilibrium studies highly fitted with the Langmuir model of monolayer adsorption considering the values of Chi-squared (χ2) and determination coefficient. The estimated adsorption energy from Dubinin-Radushkevich (0.2 kJ/mol) signifies physisorption mechanisms that might be coulombic attractive forces considering the kinetic studies. The thermodynamic addressing for the reactions verified their spontaneous and exothermic nature within a temperature range from 303 to 333 K. Additionally, the prepared MgO/CaO NRs show significant recyclability properties to be used in realistic remediation process and its uptake capacity is higher than several studied adsorbents in literature.

6.
Oncotarget ; 7(19): 28556-69, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27086919

RESUMO

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease. Novel biomarkers are required to aid treatment decisions and improve patient outcomes. MicroRNAs (miRNAs) are potentially ideal diagnostic biomarkers, as they are stable molecules, and tumour and tissue specific. RESULTS: Logistic regression analysis revealed an endoscopic-ultrasound fine-needle aspiration (EUS-FNA) 2-miRNA classifier (miR-21 + miR-155) capable of distinguishing benign from malignant pancreatic lesions with a sensitivity of 81.5% and a specificity of 85.7% (AUC 0.930). Validation FNA cohorts confirmed both miRNAs were overexpressed in malignant disease, while circulating miRNAs performed poorly. METHODS: Fifty-five patients with a suspicious pancreatic lesion on cross-sectional imaging were evaluated by EUS-FNA. At echo-endoscopy, the first part of the FNA was sent for cytological assessment and the second part was used for total RNA extraction. Candidate miRNAs were selected after careful review of the literature and expression was quantified by qRT-PCR. Validation was performed on an independent cohort of EUS-FNAs, as well as formalin-fixed paraffin embedded (FFPE) and plasma samples. CONCLUSIONS: We provide further evidence for using miRNAs as diagnostic biomarkers for pancreatic malignancy. We demonstrate the feasibility of using fresh EUS-FNAs to establish miRNA-based signatures unique to pancreatic malignant transformation and the potential to enhance risk stratification and selection for surgery.


Assuntos
Transformação Celular Neoplásica/genética , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Pâncreas/metabolismo , Neoplasias Pancreáticas/genética , Adulto , Idoso , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pâncreas/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Estudos Prospectivos , Sensibilidade e Especificidade
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