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2.
Heliyon ; 5(8): e02291, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31463397

RESUMO

Tea (Camellia Sinensis) is one of the most popular drink, consumed as infusion or bottled ready to drink beverages. Although tea leaves contain many antioxidants compounds, after processing they can drastically decrease, sometimes up to a full degradation, as in the case of catechin, a very healthy flavan-3-ol. In this context, the synthesis of a cocrystal between (+)-catechin and L-(+)-ascorbic acid, was proved to be a useful strategy to make a new ingredient able to ameliorate the antioxidant profile of both infusions and bottled teas. The obtained cocrystal showed a three-fold higher solubility than (+)catechin and its formation was elucidated unambiguously by FT-IR, thermal (DSC) and diffraction (PXRD) analyses. Antioxidant characteristics of the samples were evaluated by colorimetric assays. As expected, infusions showed much better antioxidant features than ready-to-use lemon and peach teas. The same trend was confirmed after the addition of the cocrystal at two concentration levels. In particular, supplementation at concentration of 2 mg mL-1 improved the bottled tea antioxidant values to the level showed by the not-added infusion tea.

3.
Food Res Int ; 102: 303-312, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29195952

RESUMO

In this study, during winemaking, was evaluated the influence of cultivar on bioactive compounds (organic acids, d-(+)-glucose, d-(-)-fructose, biogenic amines (BAs), anthocyanins, polyphenols and flavonoids) and antioxidant activity of Calabrian (Southern Italy) autochthonous grapes (Arvino, Gaglioppo, Greco Nero, Magliocco Canino, Magliocco Dolce and Nocera). Phenolic compounds increased from grapes to wine for all varieties. Arvino grapevine showed the highest DPPH radical scavenging activity, while a promising inhibition of the lipid peroxidation was observed with Greco Nero grapes. BAs were mostly formed during alcoholic fermentation and Arvino always showed the lowest BAs amounts, while Magliocco Canino generally exhibited the highest. Collectively, the results demonstrated that Calabrian autochthonous grapevines were rich in sugars, organic acids and phenolic compounds thus allowing the production of high quality wines.


Assuntos
Aminas Biogênicas/análise , Manipulação de Alimentos/métodos , Polifenóis/análise , Vitis/química , Vinho/análise , Antioxidantes/análise , Antioxidantes/química , Aminas Biogênicas/química , Cromatografia Líquida de Alta Pressão , Polifenóis/química , Quercetina/análise , Quercetina/química
4.
J Drug Target ; 17(1): 72-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19016107

RESUMO

Molecularly imprinted hydrogel nanospheres as devices for the controlled/sustained release of 5-fluororacil in biological fluids were synthesized employing one-pot precipitation technique as the polymerization method. Methacrylic acid as a functional monomer and ethylene glycole dimethacrylate as a cross-linker were used in polymeric feed. Morphological and hydrophilic properties were determined by scanning electron microscopy and water content measurement, and recognition and selectivity properties of spherical molecularly imprinted polymers were compared with the spherical non-imprinted polymers, both in organic (acetonitrile) and water media. Finally, in vitro release studies were performed in plasma simulating fluids.


Assuntos
Antimetabólitos Antineoplásicos/síntese química , Sistemas de Liberação de Medicamentos/métodos , Fluoruracila/síntese química , Impressão Molecular/métodos , Nanosferas/química , Acetonitrilas/química , Reagentes de Ligações Cruzadas/química , Preparações de Ação Retardada/síntese química , Etilenoglicol/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Metacrilatos/química , Microscopia Eletrônica de Varredura , Estrutura Molecular , Nanopartículas/química , Nanotecnologia/métodos , Polímeros/síntese química , Tecnologia Farmacêutica , Uracila/síntese química , Água/análise
5.
Anal Chim Acta ; 593(2): 164-70, 2007 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-17543603

RESUMO

A new sorbent for molecularly imprinted solid phase extraction (MISPE) was synthesized to extract and purify alpha-tocopherol (alpha-TP) from vegetable sources. Molecularly imprinted polymers (MIP) were synthesized using methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as crosslinking agent using a photo-polymerization procedure. A thermo-polymerization was also performed but no imprinting effect in the resulting materials was raised. The proposed MISPE protocol could overcome the drawback of traditional detection methods, which require pre-treatments of the samples. The possibility to obtain the selective recognition of alpha-TP from natural samples in aqueous mixtures represents one of the main advantages of our materials. Our procedure involves the direct HPLC injection of eluate without any treatment and above all the use of no toxic and biocompatible organic solvents. After the evaluation of the selectivity of the alpha-TP imprinted polymers, the performance of these materials as solid phase extraction (SPE) sorbents was investigated. Our MISPE-HPLC procedure has a high sensitivity, LOD and LOQ were 3.49x10(-7) and 1.16x10(-6) mol L(-1), respectively, as well as good precision (intraday precision below 3.3% and interday precisions below 6.5%) and recovery (60%). Thus, it can be successfully used for the purification of alpha-TP from bay leaves.


Assuntos
Laurus , Extração em Fase Sólida/métodos , alfa-Tocoferol/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Laurus/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , alfa-Tocoferol/química
6.
Drug Deliv ; 12(4): 229-34, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16036717

RESUMO

The aim of this research is the preparation of acryloylated bovine serum albumin microspheres and the evaluation of their employment in drug delivery. The influence of preparation parameters on albumin microspheres and the chemicophysical properties of loaded drugs were investigated. In particular, we focused our attention on acylation albumin degree, amount of acryloylated albumin against comonomer in the polymerization step, and finally the release profile. We considered on the interaction drug-matrix, the fuctionalization degree of albumin, and the water affinity of matrix.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Microesferas , Preparações Farmacêuticas/administração & dosagem , Albumina Sérica/química , Acrilatos/química , Antagonistas Adrenérgicos beta/administração & dosagem , Antagonistas Adrenérgicos beta/química , Antagonistas Adrenérgicos beta/farmacocinética , Sulfato de Amônio/química , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Azasteroides/química , Bovinos , Reagentes de Ligações Cruzadas/química , Diflunisal/administração & dosagem , Diflunisal/química , Diflunisal/farmacocinética , Di-Hidrotestosterona/análogos & derivados , Di-Hidrotestosterona/química , Estabilidade de Medicamentos , Fluoruracila/administração & dosagem , Fluoruracila/química , Fluoruracila/farmacocinética , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Compostos Organometálicos/química , Tamanho da Partícula , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , Propranolol/administração & dosagem , Propranolol/química , Propranolol/farmacocinética
7.
Drug Deliv ; 12(3): 179-84, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16025848

RESUMO

This article reports on the preparation of acryloylated bovine serum albumin microspheres and the evaluation of their employment in drug delivery areas. The influence of preparation parameters on albumin microspheres and the chemicophysical properties of loaded drugs were investigated. In particular, we focussed on acylation albumin degree and the amount of acryloylated albumin against comonomer in the polymerization step. Finally the release profile took into consideration the interaction drug-matrix, the fuctionalization degree of albumin, and the water affinity of matrix.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Microesferas , Preparações Farmacêuticas/administração & dosagem , Soroalbumina Bovina/química , Antagonistas Adrenérgicos beta/administração & dosagem , Antagonistas Adrenérgicos beta/química , Antagonistas Adrenérgicos beta/farmacocinética , Animais , Bovinos , Reagentes de Ligações Cruzadas/química , Fluoruracila/administração & dosagem , Fluoruracila/química , Fluoruracila/farmacocinética , Concentração de Íons de Hidrogênio , Imunossupressores/administração & dosagem , Imunossupressores/química , Imunossupressores/farmacocinética , Microscopia Eletrônica de Varredura , Preparações Farmacêuticas/química , Propranolol/administração & dosagem , Propranolol/química , Propranolol/farmacocinética , Tecnologia Farmacêutica/métodos , Fatores de Tempo
8.
Macromol Biosci ; 4(1): 22-6, 2004 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-15468283

RESUMO

Spherical molecularly imprinted polymers (SMIPs) have been prepared via a novel precipitation polymerization using sulfasalazine (prodrug used in the diseases of the colon) as template. The sulfasalazine was incorporated into SMIPs and into a spherical non-imprinted polymer (control), and then the release rate of the bioactive agent at different pH values was evaluated. Considerable differences in the release characteristics between imprinted and non-imprinted polymers have been observed. This opens the possibility of the development of drug release systems capable of modulating the release of a specific molecule. Photomicrography of spherical molecularly imprinted polymers (SMIPs).


Assuntos
Anti-Infecciosos/química , Metacrilatos/química , Nitrilas/química , Polímeros/síntese química , Sulfassalazina/química , Anti-Infecciosos/administração & dosagem , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos , Microesferas , Polímeros/química , Sulfassalazina/administração & dosagem , Tecnologia Farmacêutica
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