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1.
J Environ Manage ; 360: 121195, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38761622

RESUMO

The carbonization of lignocellulosic biomass with ionic liquids (ILs) are considered as an advantageous approach for the preparation of carbonaceous materials. The commonly used imidazolium and pyridinium based ILs have drawbacks such as toxicity, resistance to biodegradation, high cost and viscosity. These issues can be mitigated by diluting ILs with water, although excessive water content above 1 wt% can reduce the solubility of biomass. This research aims to investigate the potential of pretreating wastepaper with a "fully green" ILs, amino acid-based IL with high water content, followed by pyrolysis without IL, in enhancing the properties of biochar. For this purpose, the paper was treated with an aqueous solution of IL cysteine nitrate ([Cys][NO3]), and the IL was not involved in the pyrolysis process to prevent the formation of secondary gaseous pollutants. The findings revealed that the hemicellulose and mineral filler in the paper were eliminated during pretreatment, leading to higher carbon content but lower oxygen content. As a result, the biochar exhibited micropores of 0.42 cm3g-1 and a specific surface area of 1011.21 m2 g-1. The biochar demonstrated high adsorption capacities for Cd2+, enrofloxacin, bisphenol A, ciprofloxacin, and tetracycline, with values of 45.20 mg g-1, 49.82 mg g-1, 49.90 mg g-1, 49.88 mg g-1, and 49.65 mg g-1, respectively. The proposed mechanism for the adsorption of enrofloxacin by the biochar primarily involves physical adsorption such as pore filling and electrostatic interactions, along with chemical adsorption facilitated by graphitic nitrogen.


Assuntos
Aminoácidos , Carvão Vegetal , Líquidos Iônicos , Líquidos Iônicos/química , Carvão Vegetal/química , Adsorção , Aminoácidos/química
2.
Ecotoxicol Environ Saf ; 194: 110392, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32171965

RESUMO

The sensitivity of individual organisms towards toxic agents is an important indicator of environmental pollution. However, organism-specific quantification of sensitivity towards pollutants remains a challenge. In this study, we determined the sensitivity of Chlorella vulgaris (C. vulgaris) and Scenedesmus quadricauda (S. quadricauda) towards three ionic liquids (ILs), 1-alkyl-3-methyl-imidazolium chlorides [Cnmim][Cl] (n = 4,6,8). We kept all external parameters constant to identify the biotic parameters responsible for discrepancies in species sensitivity, and used flow cytometry to determine four conventional endpoints to characterise cell viability and cell vitality. Our results demonstrate that after exposure to the ILs, cell proliferation was inhibited in both species. At the same time, the cell size, complexity and membrane permeability of both algae also increased. However, while Chl a synthesis by S. quadricauda was inhibited, that of C. vulgaris was enhanced. S. quadricauda has evolved a metabolic defense that can counteract the decreased esterase activity that has been shown to occur in the presence of ILs. While it is likely that S. quadricauda was less sensitive than C. vulgaris to the ILs because of this metabolic defense, this alga may also exhibit better membrane resistance towards ILs.


Assuntos
Chlorella vulgaris/efeitos dos fármacos , Líquidos Iônicos/toxicidade , Scenedesmus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Chlorella vulgaris/citologia , Chlorella vulgaris/metabolismo , Citometria de Fluxo , Scenedesmus/citologia , Scenedesmus/metabolismo , Especificidade da Espécie
3.
Bioorg Med Chem Lett ; 24(24): 5796-5800, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25454271

RESUMO

Synthesis of a series of novel N-acylhydrazones of nicotinic acid hydrazides 3a-j via condensation of nicotinic acid hydrazide 1 with the corresponding aldehydes and ketones is described. The series 3a-j was evaluated for in vitro antibacterial activity against two gram negative (Pseudomonas aeruginosa and Klebsiella pneumoniae) and two gram positive (Streptococcus pneumoniae and Staphylococcus aureus) bacteria. The zone of inhibition was measured using the disk diffusion method, and in vitro minimum inhibitory concentration indicating that compounds 3a and 3e were effective against P. aeruginosa with MICs of 0.220 and 0.195 µg respectively.


Assuntos
Antibacterianos/síntese química , Hidrazinas/química , Ácidos Nicotínicos/química , Oxidiazóis/química , Aldeídos/química , Antibacterianos/química , Antibacterianos/farmacologia , Cristalografia por Raios X , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Cetonas/química , Conformação Molecular , Oxidiazóis/síntese química , Oxidiazóis/farmacologia
4.
Toxics ; 11(3)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36977053

RESUMO

To reduce contamination levels in Cd-contaminated paddy soil while retaining soil characteristics, we have studied the Cd-removing ability of 15 different amino acid-based ionic liquids, which are considered to be green solvents, as soil washing agents and their impact on soil. The results indicated that the glycine hydrochloride ([Gly][Cl]) removed the most Cd, and under optimized conditions could remove 82.2% of the total Cd. Encouragingly, the morphology of the soil had not been significantly changed by the washing process. After the soil was rinsed twice with water and the pH was adjusted to 6.2 by adding Ca(OH)2, the germination index of the rice increased by 7.5%. The growth of the rice was also stimulated, with lengths and weights of the rice plants increasing by 56% and 32%, respectively, after two weeks. These experiments demonstrate that amino-acid-derived ionic liquids can be promising soil-washing agents of Cd-contaminated paddy soil.

5.
Expert Opin Drug Deliv ; 20(7): 905-919, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37249548

RESUMO

INTRODUCTION: Glaucoma is a group of progressive optic neuropathies resulting in irreversible blindness. It is associated with an elevation of intraocular pressure (>21 mm Hg) and optic nerve damage. Reduction of the intraocular pressure (IOP) through the administration of ocular hypotensive eye drops is one of the most common therapeutic strategies. Patient adherence to conventional eye drops remains a major obstacle in preventing glaucoma progression. Additional problems emerge from inadequate patient education as well as local and systemic side effects associated with adminstering ocular hypotensive drugs. AREAS COVERED: Sustained-release drug delivery systems for glaucoma treatment are classified into extraocular systems including wearable ocular surface devices or multi-use (immediate-release) eye formulations (such as aqueous solutions, gels; ocular inserts, contact lenses, periocular rings, or punctual plugs) and intraocular drug delivery systems (such as intraocular implants, and microspheres for supraciliary drug delivery). EXPERT OPINION: Sustained release platforms for the delivery of ocular hypotensive drugs (small molecules and biologics) may improve patient adherence and prevent vision loss. Such innovations will only be widely adopted when efficacy and safety has been established through large-scale trials. Sustained release drug delivery can improve glaucoma treatment adherence and reverse/prevent vision deterioration. It is expected that these approaches will improve clinical management and prognosis of glaucoma.


Assuntos
Glaucoma , Humanos , Preparações de Ação Retardada , Glaucoma/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Olho , Anti-Hipertensivos/uso terapêutico , Soluções Oftálmicas/uso terapêutico
6.
Bioresour Technol ; 380: 129076, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37088432

RESUMO

This study proposes a novel method to enhance methane production from anaerobic digestion using an amino acid-derived ionic liquid, glycine hydrochloride, ([Gly][Cl]), as an exogenous additive. After 40 days of digestion with 5% [Gly][Cl], the cumulative methane production was 115.56 mL/g VS, which was 73% higher than that of the control group (without additive). Specifically, the peak activities of cellulase, xylanase, and lignin peroxidase were significantly higher than those of the control group. The addition of [Gly][Cl] increased bacterial diversity and reduced archaeal diversity. Synergistota represented by Syner-01, Fibrobacterota represented by BBMC-4, Bacteroides, and unclassified_f__Lachnospiraceae significantly increased in relative abundance. It suggested that [Gly][Cl] stimulated the activities of protein-hydrolyzing and acid-producing bacteria. [Gly][Cl] also increased the abundance of methanogens and archaea, converting more lignocellulose to methane. Methanobacterium, that metabolizes H2 and CO2 to CH4, was more abundant. Therefore, [Gly][Cl] can improve methane yield as an anaerobic digestion additive.


Assuntos
Líquidos Iônicos , Oryza , Anaerobiose , Oryza/metabolismo , Líquidos Iônicos/farmacologia , Aminoácidos/metabolismo , Bactérias/metabolismo , Archaea/metabolismo , Clostridiales/metabolismo , Metano , Reatores Biológicos/microbiologia
7.
Bioresour Technol ; 345: 126387, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34838960

RESUMO

To improve the quality of lignocellulose compost, the effect of a potential new-generation additive-amino acid-derived ionic liquid-on a compost pile comprising 50% rice straw was studied preliminarily. The addition of 1% 1-carboxymethanaminium chloride (glycine hydrochloride [Gly][Cl]) caused observably positive changes in the physical, chemical, and microbiological properties of the compost. After 30 days of composting, the humus and total nitrogen concentrations were 130.85 and 28.8 g/kg, showing an increase of 93.28% and 67.44%, respectively, compared with the concentrations in the beginning of composting; these concentrations were 76.97% and 41.69%, respectively, for the control group (without [Gly][Cl]). Thus, amino acid-derived ionic liquids can be promising additives for enhancing the quality of composts for which straw is used as the primary component.


Assuntos
Compostagem , Líquidos Iônicos , Oryza , Aminoácidos , Nitrogênio/análise , Solo
8.
Environ Pollut ; 204: 248-55, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25989452

RESUMO

Chronic effects of the ionic liquid [C4mim][Cl] (mp 73 °C) towards the microalga, Scenedesmus quadricauda were studied by flow cytometry, monitoring multiple endpoints of cell density, esterase activity, membrane integrity, reactive oxygen species and chlorophyll fluorescence. Toxicity was clearly in evidence, and although increased esterase activity indicated hormesis during initial exposure to [C4mim][Cl], inhibition of both esterase activity and chlorophyll fluorescence became apparent after 3 days. Cell density was also decreased by culturing with [C4mim][Cl], but this effect was clearly concentration-dependent and only became significant during the second half of the experiment. In contrast, [C4mim][Cl] had only a modest effect on reactive oxygen species (ROS) and caused little damage to cell membranes.


Assuntos
Imidazóis/toxicidade , Líquidos Iônicos/toxicidade , Scenedesmus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Membrana Celular/efeitos dos fármacos , Clorofila/metabolismo , Esterases/metabolismo , Citometria de Fluxo , Hormese , Espécies Reativas de Oxigênio/metabolismo , Scenedesmus/metabolismo
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