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1.
J Agric Food Chem ; 57(11): 4988-94, 2009 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-19405527

RESUMO

Important functional components from Campbell Early grape seed were extracted by ultrasound-assisted extraction (UAE) technology. The experiments were carried out according to a five level, three variable central composite rotatable design (CCRD). The best possible combinations of ethanol concentration, extraction temperature, and extraction time with the application of ultrasound were obtained for the maximum extraction of phenolic compounds, antioxidant activities, and anthocyanins from grape seed by using response surface methodology (RSM). Process variables had significant effect on the extraction of functional components with extraction time being highly significant for the extraction of phenolics and antioxidants. The optimal conditions obtained by RSM for UAE from grape seed include 53.15% ethanol, 56.03 degrees C temperature, and 29.03 min time for the maximum total phenolic compounds (5.44 mg GAE/100 mL); 53.06% ethanol, 60.65 degrees C temperature, and 30.58 min time for the maximum antioxidant activity (12.31 mg/mL); and 52.35% ethanol, 55.13 degrees C temperature, and 29.49 min time for the maximum total anthocyanins (2.28 mg/mL). Under the above-mentioned conditions, the experimental total phenolics were 5.41 mg GAE/100 mL, antioxidant activity was 12.28 mg/mL, and total anthocyanins were 2.29 mg/mL of the grape seed extract, which is well matched with the predicted values.


Assuntos
Antocianinas/química , Antioxidantes/química , Fracionamento Químico/métodos , Fenóis/química , Extratos Vegetais/química , Ultrassom , Vitis/química , Etanol/química , Sementes/química , Temperatura
2.
Biomaterials ; 25(3): 527-35, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14585702

RESUMO

This in vitro study investigated the potential of the heat-treated porcine trabecular bone block as a bone substitute for the treatment of bone defects or related diseases. Chemical, mechanical, and morphological studies of bone blocks were performed. The resultant properties were compared with the properties of currently available commercial products from bovine trabecular bones. The major component of the bone block was hydroxyapatite, and the ratio of Ca/P was 1.65-1.66. The average values of the compressive Young's modulus and the ultimate strength were 346.33 +/- 83.15 and 6.66 +/- 1.62 MPa, respectively. The pore size of the heat-treated bone blocks was approximately 300-500 microm. For the biological investigations, expanded bone marrow stromal cells (BMSCs) were isolated from the femurs of New Zealand White rabbits and were dynamically seeded into the heat-treated porcine bone block (10x10x5 mm3). Before the cells were seeded, the heat-treated porcine bone blocks were divided into two groups: collagen coated blocks (n=16) and uncoated blocks (n=16). Within each group, the blocks were again divided into two groups, depending on the culture method, i.e., static or rotating culture. Cells were cultured in the blocks for up to 6 weeks. Scanning electron microscopic examination after 4 weeks showed that the cell layers attached to the porcine bone block. Proliferation and osteogenic differentiation were analyzed by cell counting, an MTT assay, alkaline phosphatase activity, and total protein content. The deposition of extracellular substances and osteoid formation surrounded by osteoblast-like cuboidal cells were confirmed through histochemical staining and transmission electron microscopy. Based on the results of this study, we conclude that heat-treated porcine trabecular bone has great potential as a bone substitute and may even be superior to currently available commercial products.


Assuntos
Células da Medula Óssea/citologia , Osteoblastos/citologia , Osteoblastos/patologia , Animais , Substitutos Ósseos/química , Osso e Ossos/patologia , Bovinos , Diferenciação Celular , Divisão Celular , Colágeno/química , Durapatita/química , Temperatura Alta , Humanos , Técnicas In Vitro , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Coelhos , Células Estromais/citologia , Suínos , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia , Fatores de Tempo , Transplante , Difração de Raios X
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