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1.
Molecules ; 28(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37570764

RESUMO

Oil spill remediation plays a vital role in mitigating the environmental impacts caused by oil spills. The chemical method is one of the widely recognized approaches in chemical surfactants. However, the most commonly used chemical surfactants are toxic and non-biodegradable. Herein, two biocompatible and biodegradable surfactants were synthesized from orange peel using the ionic liquid 1-butyl-3-methylimidazolium chloride (BMIMCl) and organic solvent dimethylacetamide (CH3CN(CH3)2) as reaction media. The acronyms SOPIL and SOPOS refer to the surfactants prepared with BMIMCl and dimethylacetamide, respectively. The surface tension, dispersant effectiveness, optical microscopy, and emulsion stability test were conducted to examine the comparative performance of the synthesized surfactants. The Baffled flask test (BFT) was carried out to determine the dispersion effectiveness. The toxicity test was performed against zebrafish (Danio rerio), whereas the closed bottle test (CBT) evaluated biodegradability. The results revealed that the critical micelle concentration (CMC) value of SOPIL was lower (8.57 mg/L) than that of SOPOS (9.42 mg/L). The dispersion effectiveness values for SOPIL and SOPOS were 69.78% and 40.30%, respectively. The acute toxicity test demonstrated that SOPIL was 'practically non-toxic' with a median lethal concentration of more than 1000 mg/L after 96 h. The biodegradation rate was recorded as higher than 60% for both surfactants within 28 days, demonstrating their readily biodegradable nature. Considering these attributes, biocompatible and biodegradable surfactants derived from orange peel emerge as a promising and sustainable alternative for oil spill remediation.


Assuntos
Citrus sinensis , Poluição por Petróleo , Poluentes Químicos da Água , Animais , Tensoativos/toxicidade , Tensoativos/metabolismo , Poluição por Petróleo/análise , Citrus sinensis/metabolismo , Peixe-Zebra/metabolismo , Poluentes Químicos da Água/análise
2.
Int J Biol Macromol ; 194: 843-850, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34838575

RESUMO

The properties of chitin-based adsorbents varied among studies since they are influenced by different factors, such as the types of base and acid used to extract the chitin. Therefore, this works aimed to investigate the impact of four different acid solutions on the extraction and properties of chitin from shrimp shell waste, and to evaluate the adsorption performance of the obtained chitin on removing dye from an aqueous solution. The result showed that H2SO4, HCl, and HNO3 could remove high minerals from the shrimp shell, while the effect of CH3COOH was inferior. The Fourier Transform Infrared (FTIR) and X-ray diffraction (XRD) indicated that the extracted chitin was α-amorphous structure, regardless of the type of acid solution. However, the type of acid solution influenced the crystallinity index of the extracted chitin. The Scanning Electron Microscope (SEM) showed both fibrillar material and porous structures. In addition, the chitin extracted through demineralization using H2SO4 was more effective in removing RBBR dye from aqueous solution, followed by HCl, HNO3, and the last, CH3COOH treatment. The performances of chitin-based adsorbent could be attributed to the strength of acid solution used to remove mineral during the extraction process and the obtained pore structures.


Assuntos
Ácidos/química , Exoesqueleto/química , Quitina/química , Quitina/isolamento & purificação , Crustáceos/química , Soluções/química , Adsorção , Animais , Fracionamento Químico , Cinética , Análise Espectral , Resíduos
3.
J Hazard Mater ; 177(1-3): 683-91, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20060641

RESUMO

Ceiba pentandra (L.) Gaertn (kapok) is a natural sorbent that exhibits excellent hydrophobic-oleophilic characteristics. The effect of packing density, the oil types and solvent treatment on the sorption characteristics of kapok was studied in a batch system. Oil sorption capacity, retention capacity, entrapment stability and kapok reusability were evaluated. Based on SEM and FTIR analyses, kapok fiber was shown to be a lignocellulosic material with hydrophobic waxy coating over the hollow structures. Higher packing density at 0.08 g/ml showed lower sorption capacity, but higher percentage of dynamic oil retention, with only 1% of oil drained out from the test cell. Kapok remained stable after fifteen cycles of reuse with only 30% of sorption capacity reduction. The oil entrapment stability at 0.08 g/ml packing was high with more than 90% of diesel and used engine oil retained after horizontal shaking. After 8h of chloroform and alkali treatment, 2.1% and 26.3% reduction in sorption capacity were observed, respectively, as compared to the raw kapok. The rigid hollow structure was reduced to flattened-like structure after alkali treatment, though no major structural difference was observed after chloroform treatment. Malaysian kapok has shown great potential as an effective natural oil sorbent, owing to high sorption and retention capacity, structural stability and high reusability.


Assuntos
Biodegradação Ambiental , Ceiba/metabolismo , Óleos/farmacocinética , Adsorção , Conservação dos Recursos Naturais , Interações Hidrofóbicas e Hidrofílicas , Malásia , Óleos/isolamento & purificação , Solventes
4.
Open Med Chem J ; 2: 49-61, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-19662143

RESUMO

Biopharmaceuticals are often produced by recombinant E. coli or mammalian cell lines. This is usually achieved by the introduction of a gene or cDNA coding for the protein of interest into a well-characterized strain of producer cells. Naturally, each recombinant production system has its own unique advantages and disadvantages. This paper examines the current practices, developments, and future trends in the production of biopharmaceuticals. Platform technologies for rapid screening and analyses of biosystems are reviewed. Strategies to improve productivity via metabolic and integrated engineering are also highlighted.

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