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Abstract(s)
O objectivo deste trabalho foi a extracção, isolamento e purificação de compostos fenólicos
existentes na cerejeira (Prunus avium), bem como a determinação da actividade antioxidante
dos extractos e compostos puros.
A madeira é um dos principais materiais utilizados pela humanidade possuindo várias
aplicações, sendo também matéria-prima para múltiplos produtos. Em particular, a madeira
de cerejeira possui uma elevada importância económica, pois apresenta diversas
características importantes, tendo na sua constituição diversos compostos com interesse
biológico.
Foi realizado o estudo do extracto da madeira de cerejeira com acetona, previamente
extraída por extracção de Soxhlet, realizando-se o isolamento e purificação por cromatografia em coluna, para identificação dos produtos puros obtidos. A caracterização estrutural foi efectuada por espectroscopia de ressonância magnética nuclear de protão (1H-RMN) e de carbono (13C-RMN) permitindo confirmar a existência de compostos fenólicos nos extractos analisados. As estruturas dos compostos identificados foram então comparadas com as estruturas propostas pelo grupo de trabalho, bem como as estruturas já descritas na literatura.
Foi realizada a determinação da actividade antioxidante dos extractos da casca da madeira, dos pés de cereja, das folhas e da madeira de cerejeira, bem como do composto catequina isolada a partir do extracto da madeira de cerejeira, utilizando o método do radical DPPH (2,2-difenil-1-picril hidrazilo), baseado na capacidade que este radical tem em reagir com doadores de hidrogénio para conhecimento da sua actividade antioxidante, utilizando como
referência o antioxidante comercialmente conhecido como Quercetina.
The main objective of this work was the extraction, isolation and purification of phenolic compounds existing in cherry (Prunus avium), and the determination of antioxidant activity of extracts and pure compounds. Wood is one of the main materials used by humanity featuring multiple applications, and raw material for multiple products. In particular, the cherry wood has a high economic importance, because it introduces several important features and possesses several biological compounds with interest. Study of extract with acetone of wood of cherry tree, previously extracted with Soxhlet extractor, was made by column chromatography and was isolated and purified several products, which were identified. Structural characterization was undertaken by nuclear magnetic resonance spectroscopy of proton (1H-NMR) and carbon (13C-NMR) allowing confirming the existence of phenolic compounds in the extracts analyzed. The structures identified were then compared to those already described in literature. Determination of antioxidant activity of the extracts from the wood bark, the feet of cherry, leaves and wood of cherry tree, and the compound catechin isolated from the extract of wood of cherry tree, based on the ability of this radical has to react with hydrogen donor for knowledge of their antioxidant activity, using as a reference commercially product known as Quercetin.
The main objective of this work was the extraction, isolation and purification of phenolic compounds existing in cherry (Prunus avium), and the determination of antioxidant activity of extracts and pure compounds. Wood is one of the main materials used by humanity featuring multiple applications, and raw material for multiple products. In particular, the cherry wood has a high economic importance, because it introduces several important features and possesses several biological compounds with interest. Study of extract with acetone of wood of cherry tree, previously extracted with Soxhlet extractor, was made by column chromatography and was isolated and purified several products, which were identified. Structural characterization was undertaken by nuclear magnetic resonance spectroscopy of proton (1H-NMR) and carbon (13C-NMR) allowing confirming the existence of phenolic compounds in the extracts analyzed. The structures identified were then compared to those already described in literature. Determination of antioxidant activity of the extracts from the wood bark, the feet of cherry, leaves and wood of cherry tree, and the compound catechin isolated from the extract of wood of cherry tree, based on the ability of this radical has to react with hydrogen donor for knowledge of their antioxidant activity, using as a reference commercially product known as Quercetin.
Description
Keywords
Compostos fenólicos Cereja Radical DPPH Flavonóides