Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 82
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Mol Sci ; 22(17)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34502276

RESUMO

Tested in vitro on SH-SY5Y neuroblastoma cells, grapefruit IntegroPectin is a powerful protective, antioxidant and antiproliferative agent. The strong antioxidant properties of this new citrus pectin, and its ability to preserve mitochondrial membrane potential and morphology, severely impaired in neurodegenerative disorders, make it an attractive therapeutic and preventive agent for the treatment of oxidative stress-associated brain disorders. Similarly, the ability of this pectic polymer rich in RG-I regions, as well as in naringin, linalool, linalool oxide and limonene adsorbed at the outer surface, to inhibit cell proliferation or even kill, at high doses, neoplastic cells may have opened up new therapeutic strategies in cancer research. In order to take full advantage of its vast therapeutic and preventive potential, detailed studies of the molecular mechanism involved in the antiproliferative and neuroprotective of this IntegroPectin are urgently needed.

2.
Chem Commun (Camb) ; 57(71): 8897-8900, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34486604

RESUMO

The ABNO@PMO-IL-Br material obtained by anchoring 9-azabicyclo[3.3.1]nonane-3-one N-oxyl (keto-ABNO) within the mesopores of periodic mesoporous organosilica with bridged imidazolium groups is a robust bifunctional catalyst for the metal-free aerobic oxidation of numerous primary and secondary alcohols under oxygen balloon reaction conditions. The catalyst, furthermore, can be successfully employed in the first metal-free self-esterification of primary aliphatic alcohols affording valued esters.

3.
Nanomedicine (Lond) ; 16(23): 2061-2074, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34533057

RESUMO

Aim: To assess whether Omeg@Silica microparticles - fish oil from anchovy fillet leftovers (AnchoisOil) encapsulated within mesoporous silica particles - are effective in promoting antitumor effects in lung cancer cells. Methods: Three human non-small-cell lung cancer cell lines (A549, Colo 699 and SK-MES-1) were used. Cells were treated with AnchoisOil dispersed in ethanol (10 and 15 µg/ml) or encapsulated in silica and further formulated in aqueous ethanol. Cell cycle, reactive oxygen species, mitochondrial stress and long-term proliferation were assessed. Results & conclusion: Omeg@Silica microparticles were more effective than fish oil in increasing reactive oxygen species and mitochondrial damage, and in altering the cell cycle and reducing cell proliferation, in lung cancer cells. These in vitro antitumor effects of Omeg@Silica support its investigation in lung cancer therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Linhagem Celular Tumoral , Óleos de Peixe , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Dióxido de Silício
4.
Chem Commun (Camb) ; 57(64): 7863-7868, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34287441

RESUMO

Drawing on independent work carried out by academic and industrial researchers using the immobilized TEMPO catalyst SiliaCat TEMPO, in this study we show how shifting the carboxylation process mediated by TEMPO in solution to a process mediated by the above-mentioned hybrid sol-gel catalyst allows the synthesis of insoluble polysaccharide nanofibers of superior quality, eliminating waste. This will dramatically reduce the polysaccharide nanofiber production costs opening the route to large-scale production and uptake of these versatile nanofibers in a variety of functional products where their use has been limited by high cost. The results of this study will be useful for catalysis and biotechnology researchers as well as for chemistry educators teaching green chemistry, nanochemistry, and catalysis using the outcomes of recent research.


Assuntos
Óxidos N-Cíclicos/química , Nanofibras/química , Polissacarídeos/química , Configuração de Carboidratos , Radicais Livres/química , Humanos , Oxirredução , Tamanho da Partícula
5.
ChemistryOpen ; 10(5): 581-586, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33945233

RESUMO

Fish oil rich in long-chain polyunsaturated fatty acids, vitamin D3 and carotenoid pigments have been sustainably extracted from anchovy fillet leftovers using biobased limonene. The oil is conveniently stabilized by adsorption on periodic mesoporous silicas. The simplicity of the process, the high load of fish oil, and the biocompatible nature of mesoporous silica support numerous forthcoming applications of this new class of "Omeg@Silica" materials.

6.
Molecules ; 26(3)2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33498706

RESUMO

Isolating cellulose from citrus processing waste without employing chemicals has so far been an unfulfilled goal of chemical research applied to the valorization of a widely available biowaste, annually totaling >100 million tonnes. We have applied hydrodynamic cavitation using a Venturi-type reactor for the extraction of all valued bioproducts of industrial citrus processing waste in water only, directly on a semi-industrial scale. After reporting the discovery of IntegroPectin in the soluble fraction of the aqueous extract, we now report the isolation of a cellulosic material in the water-insoluble fraction of cavitated lemon and grapefruit processing waste. Named "CytroCell", the material is cellulose of low crystallinity, high porosity, good water holding capacity and good dispersibility in water. These properties open the route to mass-scale production of a useful functional material from a cheap and abundant biowaste.


Assuntos
Celulose/química , Citrus/química , Resíduos Industriais/análise , Citrus paradisi/química , Frutas/química , Resíduos/análise
7.
Molecules ; 26(1)2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33374383

RESUMO

An HS-SPME GC-MS analysis of the volatile compounds adsorbed at the outer surface of lemon and grapefruit pectins obtained via the hydrodynamic cavitation of industrial waste streams of lemon and grapefruit peels in water suggests important new findings en route to understanding the powerful and broad biological activity of these new pectic materials. In agreement with the ultralow degree of esterification of these pectins, the high amount of highly bioactive α-terpineol and terpinen-4-ol points to limonene (and linalool) decomposition catalyzed by residual citric acid in the citrus waste peel residue of the juice industrial production.


Assuntos
Citrus paradisi/química , Citrus/química , Compostos Orgânicos Voláteis/química , Vias Biossintéticas , Citrus/metabolismo , Citrus paradisi/metabolismo , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Estrutura Molecular , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
8.
Antibiotics (Basel) ; 9(9)2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32911640

RESUMO

Grapefruit and lemon pectin obtained from the respective waste citrus peels via hydrodynamic cavitation in water only are powerful, broad-scope antimicrobials against Gram-negative and -positive bacteria. Dubbed IntegroPectin, these pectic polymers functionalized with citrus flavonoids and terpenes show superior antimicrobial activity when compared to commercial citrus pectin. Similar to commercial pectin, lemon IntegroPectin determined ca. 3-log reduction in Staphylococcus aureus cells, while an enhanced activity of commercial citrus pectin was detected in the case of Pseudomonas aeruginosa cells with a minimal bactericidal concentration (MBC) of 15 mg mL-1. Although grapefruit and lemon IntegroPectin share equal MBC in the case of P. aeruginosa cells, grapefruit IntegroPectin shows boosted activity upon exposure of S. aureus cells with a 40 mg mL-1 biopolymer concentration affording complete killing of the bacterial cells. Insights into the mechanism of action of these biocompatible antimicrobials and their effect on bacterial cells, at the morphological level, were obtained indirectly through Fourier Transform Infrared spectroscopy and directly through scanning electron microscopy. In the era of antimicrobial resistance, these results are of great societal and sanitary relevance since citrus IntegroPectin biomaterials are also devoid of cytotoxic activity, as already shown for lemon IntegroPectin, opening the route to the development of new medical treatments of polymicrobial infections unlikely to develop drug resistance.

9.
ChemMedChem ; 15(23): 2228-2235, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-32857470

RESUMO

First reported in the late 1930s and partly explained in 1970, the antibacterial activity of pectin remained almost ignored until the late 1990s. The concomitant emergence of research on natural antibacterials and new usages of pectin polysaccharides, including those in medicine widely researched in Russia, has led to a renaissance of research into the physiological properties of this uniquely versatile polysaccharide ubiquitous in plants and fruits. By collecting scattered information, this study provides an updated overview of the subtle factors affecting the behaviour of pectin as an antimicrobial. Less-degraded pectin extracted by acid-free routes, we argue in the conclusions, will soon find applications from new treatments for polymicrobial infections to use as an implantable biomaterial in tissue and bone engineering.

10.
ChemMedChem ; 15(17): 1619-1623, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32657536

RESUMO

The rediscovery of the medical uses of silver provides another noticeable example, this time at the interface of chemistry and medicine, of the real (and nonlinear) progress of scientific research. Several new silver-based antimicrobial products have thus been commercialized in the last two decades. Next-generation antibacterials and antivirals of broad scope, low toxicity and affordable cost, we argue in this study, will be based on microencapsulated Ag nanoparticles.


Assuntos
Antibacterianos/farmacologia , Antivirais/farmacologia , Bactérias/química , Nanopartículas Metálicas/química , Prata/farmacologia , Vírus/efeitos dos fármacos , Antibacterianos/química , Antivirais/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Prata/química
11.
ACS Omega ; 5(28): 17500-17505, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32715235

RESUMO

A valued marine oil rich in omega-3 lipids and natural astaxanthin is obtained with remarkably high yield (up to 5 wt %) extending to pink shrimp waste (head and carapace) using the approach to extract fish oil from fish processing byproducts using d-limonene. Biobased limonene is an excellent solvent for both unsaturated lipids and astaxanthin-based carotenoids preventing oxidative degradation during the extraction cycle including solvent separation at 85 °C. Explaining the deep red color of the shrimp oil obtained, computational simulation suggests that d-limonene is also a good solvent for natural astaxanthin abundant in shrimp.

12.
ChemistryOpen ; 9(5): 628-630, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32489768

RESUMO

Pectin extracted via hydrodynamic cavitation in water only from waste lemon peel and further isolated via freeze drying displays significant antibacterial activity against Staphylococcus aureus, a Gram positive pathogen which easily contaminates food. The antibacterial effect of the new IntegroPectin is largely superior to that of commercial citrus pectin, opening the way to advanced applications of a new bioproduct now obtainable in large amounts and at low cost from citrus juice industry's waste.

13.
Front Chem ; 8: 191, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32318540

RESUMO

Silicon quantum dots (SiQDs) are semiconductor Si nanoparticles ranging from 1 to 10 nm that hold great applicative potential as optoelectronic devices and fluorescent bio-marking agents due to their ability to fluoresce blue and red light. Their biocompatibility compared to conventional toxic Group II-VI and III-V metal-based quantum dots makes their practical utilization even more attractive to prevent environmental pollution and harm to living organisms. This work focuses on their possible use for light-emitting diode (LED) manufacturing. Summarizing the main achievements over the past few years concerning different Si quantum dot synthetic methods, LED formation and characteristics, and strategies for their stabilization by microencapsulation and modification of their surface by specific ligands, this work aims to provide guidance en route to the development of the first stable Si-based light-emitting diodes.

14.
ChemistryOpen ; 9(4): 459-463, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32280580

RESUMO

Consisting of organically modified silica (ORMOSIL) physically doped with Ag nanoparticles, the SilverSil new class of antibacterial materials of broad scope reported herein shows remarkably high and stable activity against representative Gram-positive and Gram-negative bacteria. The low cost, ease of application and excellent health and environmental profile of SilverSil hybrid glassy coatings open the route to their widespread utilization across domestic, hospital, school, industrial and commercial environments and in consumer products.


Assuntos
Antibacterianos/química , Nanopartículas Metálicas/química , Dióxido de Silício/química , Prata/química , Antibacterianos/farmacologia , Desenvolvimento de Medicamentos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Porosidade , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície
15.
Materials (Basel) ; 13(4)2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32059427

RESUMO

An innovative catalyst is reported for removing suspect carcinogen trichloroacetic acid (TCA) found in water after chlorination. SilverSil, a methyl-modified silica xerogel doped with Ag nanoparticles, shows remarkably high and stable activity as heterogeneous catalyst for the reductive dehalogenation of TCA with NaBH4 as reducing agent. Chloroacetic acid and acetic acid are the main products of the highly reproducible reductive dehalogenation. The low cost, high stability and ease of application of the SilverSil sol-gel catalyst to continuous processes open the route to the industrial uptake of SilverSil to free chlorinated waters from a probable human carcinogenic agent exerting significant genotoxic and cytotoxic effects.

16.
ChemistryOpen ; 9(1): 8-13, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31921539

RESUMO

The global adoption of biodegradable and compostable plastics obtained from biomass-derived monomers, we argue in this account, is now close to the inflection point. The first industrially significant impact will affect the packaging segment of the global chemical industry. In this process, China and India will play a pivotal role. Selected guidelines aiming to foster development of bioplastics industry in both developed and developing nations are provided.


Assuntos
Plásticos Biodegradáveis/química , Biodegradação Ambiental , China , Meio Ambiente , Índia , Embalagem de Produtos , Reciclagem , Solo , Instalações de Eliminação de Resíduos , Gerenciamento de Resíduos
17.
Heliyon ; 6(1): e03087, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31922044

RESUMO

From professors overwhelmed by anxiety-driven e-mails from students, through faculty and administrative staff wasting valued time on e-mail minutia, misuse of electronic mail in the academy has become ubiquitous. After a brief overview of the unique features of e-mail communication, this study provides guidelines to plan new educational activities on purposeful utilization of electronic mail in university and research centres of the digital era. The overall aim is to prioritize scholarly deep work by focusing on teaching and research work, freeing working time wasted on unproductive use of e-mail.

18.
Glob Chall ; 3(10): 1900016, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31592333

RESUMO

The replacement of fossil fuels to produce electricity and heat to propel vehicles with solar energy, along with other new energy technologies, will bring significant economic, environmental, and social benefits to all Mediterranean countries. The transition to new energy, however, calls for a proactive and creative role of policy makers.

19.
ACS Omega ; 4(13): 15359-15363, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31572834

RESUMO

We investigate selected chemical, technical, and economic aspects of the production of fish oil rich in polyunsaturated omega-3 fatty acids from anchovy filleting leftovers using d-limonene as the extraction solvent at ambient temperature and pressure. Entirely derived from the orange peel prior to orange squeezing for juice production, the bio-based solvent is easily recovered, affording a circular economy process with significant potential for practical applications.

20.
Glob Chall ; 3(8): 1800105, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31565388

RESUMO

The Internet of Things approach to manage clean electricity produced from sun, wind, and water is, alongside the hydrogen fuel cell and the Li-ion battery, the key enabling technology for the transition to 100% renewable energy. Practical examples from distant countries are used to show how today's digital control technology is actually used to ease the generation and utilization of clean, reliable, and cheap solar energy on an annual basis. The conclusions are of relevance also to the redesign of energy education programs in response to dramatic changes in energy technologies.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...