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1.
Molecules ; 28(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37175170

RESUMO

Agronomic practices and the winemaking process lead to the production of considerable quantities of waste and by-products. These are often considered waste with negative effects on environmental sustainability. However, vine shoots and grape stalks can be reused, representing a potential source of xylo-oligosaccharides and polyphenols. In this context, the purpose of this work was to obtain enriched extracts using three different autohydrolysis treatments with (i) H2O, (ii) H2O:EtOH, and (iii) H2O:Amberlyst. The obtained extracts were characterized by their xylo-oligosaccharide and polyphenol profiles using LC-MS techniques. The use of ethanol during autohydrolysis allowed for greater extraction of xylan-class compounds, especially in vine shoot samples, while an increase in antioxidant activity (128.04 and 425.66 µmol TE/g for ABTS and DPPH, respectively) and in total phenol content (90.92 mg GAE/g) was obtained for grape stalks.


Assuntos
Vitis , Vitis/química , Fenóis , Oligossacarídeos/química , Polifenóis , Extratos Vegetais/química , Antioxidantes/farmacologia , Etanol
2.
Molecules ; 22(2)2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28230803

RESUMO

An innovative and eco-friendly one-pot synthesis of bio-based polyurethanes is proposed via the epoxy-ring opening of epoxidized soybean oil (ESO) with methanol, followed by the reaction of methoxy bio-polyols intermediates with 2,6-tolyl-diisocyanate (TDI). Both synthetic steps, methanolysis and polyurethane linkage formation, are promoted by a unique catalyst, molybdenum(VI) dichloride dioxide (MoCl2O2), which makes this procedure an efficient, cost-effective, and environmentally safer method amenable to industrial scale-up.


Assuntos
Técnicas de Química Sintética , Poliuretanos/síntese química , Óleo de Soja/química , Catálise , Oxirredução , Espectroscopia de Prótons por Ressonância Magnética
3.
ScientificWorldJournal ; 2013: 212156, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24163617

RESUMO

This work addresses a new approach developed in our laboratory, consisting in the application of isolated dimethyldioxirane (DDO, 1a) labelled with ¹8O for synthesis of epoxidized glyceryl linoleate (Gly-LLL, 2). We expect that this work could contribute in improving analytical methods for the determination of epoxidized soybean oil (ESBO) in complex food matrices by adopting an ¹8O-labelled-epoxidized triacylglycerol as an internal standard.


Assuntos
Compostos de Epóxi/química , Isótopos de Oxigênio/química , Óleo de Soja/química , Estrutura Molecular
4.
Food Chem ; 134(2): 1192-8, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23107747

RESUMO

The adulteration of extra virgin olive oil (EVOO) with hazelnut oil (HO) is frequent and constitutes a serious concern both for oil suppliers and consumers. The high degree of similarity between the two oils as regards triacylglycerol, total sterol and fatty acid profile, complicates the detection of low percentages of HO in EVOO. However, phospholipids (PLs) are usually present in seed oils at a concentration range of 10-20 g/kg, while the amounts of PLs in VOOs are 300-400 times lower. Thus, in this work a sample pretreatment procedure focused towards the selective PLs extraction was developed; the Bligh-Dyer extraction procedure was modified introducing the ionic liquid resulting from the combination of TBA (tributylamine) and CHCA (α-Cyano-4-hydroxycinnamic acid) as extraction solvent. The selective extraction and enrichment of phospholipids from EVOO and HO samples was then achieved. The relevant extracts were analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) using the same ionic liquid TBA-CHCA as MALDI matrix, that was found to be very suitable for PLs analysis. In fact, a remarkable increase of the phospholipids signals, with a simultaneous decrease of those relevant to triacylglycerols and diacylglycerols, was observed in the relevant mass spectra. The applicability of the whole method to the individuation of the presence of HO in EVOO was demonstrated by the analysis of EVOO samples progressively adulterated with variable quantities of HO, that was still detectable at a 1% contamination level.


Assuntos
Corylus/química , Contaminação de Alimentos/análise , Extração Líquido-Líquido/métodos , Fosfolipídeos/análise , Óleos de Plantas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Líquidos Iônicos/química , Extração Líquido-Líquido/instrumentação , Azeite de Oliva
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