Avaliação da atividade antioxidante e compostos fenólicos de extratos vegetais

• Main Author: Souza, Wagner de
• Publication Date: 2013
• Format: Bachelor thesis
• Language: por
• Source: Repositório Institucional da UTFPR (da Universidade Tecnológica Federal do Paraná (RIUT))
• Download full: http://repositorio.utfpr.edu.br/jspui/handle/1/6514
• topic: Fenóis; Folhas; Antioxidantes; Phenols; Leaves; Antioxidants; Tecnologia em Alimentos

An important challenge for the research industry in recent years is the search for natural antioxidants for food products, cosmetics and pharmaceuticals. These antioxidants are obtained primarily from vegetable products, of which phenolic compounds are included. These compounds are part of plant secondary metabolism and are found on the stem, fruit, root , and especially the leaves. For this work were acquired sheets acerola, guava , cherry , guabiroba , guava and cherry coming from sites in the region of Campo Mourao. The extraction CFT (total phenolic compounds) was made with 80% ethanol (v / v) acidified with HCl 0.5% (v / v) at high temperature. Then they were quantified and the evaluation of their antioxidant activity used the ABTS method , which is based on the decolorization of the molecule across a substance antioxidant. Therefore, the CFT amount ranging from 2449,7 to 20626,2 mg to AG/100g sheet and acerola cherry extracts , respectively. In contrast, the antioxidant activity of these extracts was at least 3040, 85 mM Trolox / g for sheet acerola , while the maximum value was 13439.45 mM Trolox / g extract of guabiroba . Given these results, no correlation was found between phenolic compounds and antioxidant activity. However, the concentration of phenolic compounds with acidic ethanol in boiling water were high in comparison with other extraction conditions , and that leaves can be considered as potential sources of natural antioxidants.