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1.
J Agric Food Chem ; 70(20): 6191-6201, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35543583

RESUMO

The similarity of the fat fraction in infant formulas rich in either bovine milk fat (MF) or vegetable oil (VO) to breast milk was evaluated by analyzing their lipid composition. Milk fat-rich formulas were highly similar (average similarity index 0.68) to breast milk compared to the VO-rich formulas (average similarity index 0.56). The highest difference in the indices was found in the contents of cholesterol (0.66 vs 0.28 in MF- and VO-rich formulas, respectively, on average) and polar lipids (0.84 vs 0.53), the positional distribution of fatty acids in the sn-2 position of triacylglycerols (0.53 vs 0.28), and fatty acid composition (0.72 vs 0.54). The VO-based formulas were superior in similarity in n - 6 PUFA. Thus, the addition of bovine MF fractions is an effective way to increase the similarity between the lipid composition of infant formulas and human milk.


Assuntos
Fórmulas Infantis , Leite Humano , Animais , Ácidos Graxos , Feminino , Humanos , Lactente , Leite , Óleos de Plantas , Triglicerídeos
2.
Microporous Mesoporous Mater ; 334: 111760, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35221784

RESUMO

The worldwide spread of the SARS-CoV-2 virus has continued to accelerate, putting a considerable burden on public health, safety, and the global economy. Taking into consideration that the main route of virus transmission is via respiratory particles, the face mask represents a simple and efficient barrier between potentially infected and healthy individuals, thus reducing transmissibility per contact by reducing transmission of infected respiratory particles. However, long-term usage of a face mask leads to the accumulation of significant amounts of different pathogens and viruses onto the surface of the mask and can result in dangerous bacterial and viral co-infections. Zeolite imidazolate framework-8 (ZIF-8) has recently emerged as an efficient water-stable photocatalyst capable of generating reactive oxygen species under light irradiation destroying dangerous microbial pathogens. The present study investigates the potential of using ZIF-8 as a coating for face masks to prevent the adherence of microbial/viral entities. The results show that after 2 h of UV irradiation, a polypropylene mask coated with ZIF-8 nanostructures is capable of eliminating S. Aureus and bacteriophage MS2 with 99.99% and 95.4% efficiencies, respectively. Furthermore, low-pathogenic HCoV-OC43 coronavirus was eliminated by a ZIF-8-modified mask with 100% efficiency already after 1 h of UV irradiation. As bacteriophage MS2 and HCoV-OC43 coronavirus are commonly used surrogates of the SARS-CoV-2 virus, the revealed antiviral properties of ZIF-8 can represent an important step in designing efficient protective equipment for controlling and fighting the current COVID-19 pandemic.

3.
3 Biotech ; 10(10): 415, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32953378

RESUMO

The gas chromatography of hexane extracts from ascocarps of Tuber maculatum (mostly the first report), T. aestivum/unicantum, T. borchii, T. melanosporum and Tirmania nivea dominantly showed palmitic, stearic, oleic and linoleic acids followed by traces of polyunsaturated fatty acids. The fatty acid content varied from ca. 8-61 mg g- 1, dry-weight-basis with species with highest for T. maculatum. Polyunsaturated fatty acids contributions varied from ca. 42-59%. The dominant fatty acid varied with the species. A comparison with existing reports on same species cultivated in different regions showed differences in contributions by saturated, monounsaturated and polyunsaturated fatty acids as well as dominant fatty acids detected. Lesser explored species such as T. borchii, T. maculatum call for further research. This is a preliminary study that indicates fatty acid composition as a potential tool for distinction like aroma between truffle species and geographies of cultivation. This forms the basis for further studies in different species and regions.

4.
Int J Biol Macromol ; 118(Pt A): 903-912, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29964103

RESUMO

A novel hydroxyapatite-bentonite clay-nanocellulose (CHA-BENT-NCC) composite material was successfully prepared as adsorbent for the removal of Ni2+, Cd2+ and PO43- from aqueous solutions. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive analysis of X-rays (EDAX), X-ray diffraction analysis (XRD) and Fourier-transform infrared spectroscopy (FTIR) were used for characterization of the adsorbent. The effect of pH, contact time, temperature, and initial adsorbate concentration were studied for optimization purpose. The adsorption behavior of the investigated ions were well described by the Freundlich adsorption model, and the maximum adsorption capacity for Ni2+, Cd2+ and PO43- was estimated to be 29.46 mmol/g, 10.34 mmol/g and 4.90 mmol/g, respectively. Desorption efficiency was achieved by treatment with 0.01 M HNO3 for metals and 0.10 M NaOH for PO43-. Five adsorption-desorption cycles were performed without significant decrease in adsorption capacities. The CHA-BENT-NCC material proved to be a very effective adsorption material for the treatment of mining water also from a copper mine in Finland.


Assuntos
Bentonita/química , Cádmio/química , Celulose/química , Durapatita/química , Nanocompostos/química , Níquel/química , Fosfatos/química , Purificação da Água , Adsorção
5.
Environ Technol ; 39(8): 952-966, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28406056

RESUMO

In the present study, the adsorption of sulfates of sodium sulfate (Na2SO4) and sodium lauryl sulfate (SLS) by calcium hydroxyapatite-modified microfibrillated cellulose was studied in the aqueous solution. The adsorbent was characterized using elemental analysis, Fourier transform infrared, scanning electron microscope and elemental analysis in order to gain the information on its structure and physico-chemical properties. The adsorption studies were conducted in batch mode. The effects of solution pH, contact time, the initial concentration of sulfate and the effect of competing anions were studied on the performance of synthesized adsorbent for sulfate removal. Adsorption kinetics indicated very fast adsorption rate for sulfate of both sources (Na2SO4 and SLS) and the adsorption process was well described by the pseudo-second-order kinetic model. Experimental maximum adsorption capacities were found to be 34.53 mg g-1 for sulfates of SLS and 7.35 mg g-1 for sulfates of Na2SO4. The equilibrium data were described by the Langmuir, Sips, Freundlich, Toth and Redlich-Peterson isotherm models using five different error functions.


Assuntos
Celulose/química , Durapatita/química , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos , Termodinâmica , Poluentes Químicos da Água
6.
Water Res ; 91: 156-73, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26789698

RESUMO

In recent decades, increased domestic, agricultural and industrial activities worldwide have led to the release of various pollutants, such as toxic heavy metals, inorganic anions, organics, micropollutants and nutrients into the aquatic environment. The removal of these wide varieties of pollutants for better quality of water for various activities is an emerging issue and a robust and eco-friendly treatment technology is needed for the purpose. It is well known that cellulosic materials can be obtained from various natural sources and can be employed as cheap adsorbents. Their adsorption capacities for heavy metal ions and other aquatic pollutants can be significantly affected upon chemical treatment. In general, chemically modified cellulose exhibits higher adsorption capacities for various aquatic pollutants than their unmodified forms. Numerous chemicals have been used for cellulose modifications which include mineral and organic acids, bases, oxidizing agent, organic compounds, etc. This paper reviews the current state of research on the use of cellulose, a naturally occurring material, its modified forms and their efficacy as adsorbents for the removal of various pollutants from waste streams. In this review, an extensive list of various cellulose-based adsorbents from literature has been compiled and their adsorption capacities under various conditions for the removal of various pollutants, as available in the literature, are presented along with highlighting and discussing the key advancement on the preparation of cellulose-based adsorbents. It is evident from the literature survey presented herein that modified cellulose-based adsorbents exhibit good potential for the removal of various aquatic pollutants. However, still there is a need to find out the practical utility of these adsorbents on a commercial scale, leading to the improvement of pollution control.


Assuntos
Celulose/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção
7.
Environ Technol ; 35(17-20): 2334-46, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25145187

RESUMO

In the present study, microfibrillated cellulose (MFC) was modified by aminopropyltriethoxysilane (APS), hydroxy-carbonated apatite (HAP), or epoxy in order to produce novel nanostructured adsorbents for the removal of hydrogen sulphide (H2S) from the aqueous solutions. Structural properties of the modified MFC materials were examined using a scanning electron microscope, Fourier transform infrared spectroscopy and acid/base titration. These methods were used to verify the presence of nanostructures on the adsorbents surfaces as well as functionalities suitable for H2S adsorption. Adsorption of H2S by prepared adsorbents was investigated in batch mode under different experimental conditions, i.e., varying pH and H2S concentrations. H2S uptake was found to be 103.95, 13.38 and 12.73 mg/g by APS/MFC, HAP/MFC and epoxy/MFC, respectively from 80 mg/L H2S solution. The equilibrium data were best described by the Langmuir isotherm for HAP/MFC and APS/MFC and the Sips isotherm for epoxy/MFC.


Assuntos
Celulose/química , Sulfeto de Hidrogênio/isolamento & purificação , Nanotecnologia/instrumentação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/instrumentação , Adsorção , Sulfeto de Hidrogênio/química , Concentração de Íons de Hidrogênio , Nanotecnologia/métodos , Temperatura , Poluentes Químicos da Água/química , Purificação da Água/métodos
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