Caracterização bioquímica de sementes de 6 variedades de feijão de corda Vigna unguiculata (L.) Walp.

• Ano de defesa: 1996
• Autor(a) principal: Castellon, Rolando Enrique Rivas
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Agronomia
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/43928

The partial biochemical composition of seed flour from 6 varieties of cowpea, Vigna unguiculata (L.) Walp. (Br 14 Mulato, Br 9 Longá, Br 17 Gurguéia, CNC 0434, VlTA 7, and CE 315) was evaluated by determing their lipid content, the fatty acid composition of the oils, the fractionation in different protein (globulins, albumins, glutelins and prolamins), the amount of total soluble protein extracted at different pH, and the presence of hemagglutination activity in the extracts (flour and fractions). The screening for the presence of hemagglutinins (lectins) was carried out by hemagglutination assays whereby the different extracts of each variety (pH 2,6; 7,6 and 9,0) were evaluated by their capacity to clump either normal or proteolytically treated erythroytes from humans (A,B and O blood groups) and rabit. For this porpose, erythrocites treated with bromelain, papain, subtilisin and trypsin were used. In adition, the eletrophoretic pattern under denaturations and reductions conditions of the seed protein was analysed, finaly, the amino acid composition of flour and fraction were determined. The seeds from the 6 varieties investigated showed a low fat content as usually found in a large numbers of legumes seeds, in the range of 1,23 to 1,71% of the dry seed weight. The Br 14 and Br 9 cowpea varieties showed the grater specificactivity in the hemagglutination assays than other varieties; the presence of hemagglutination activity in differents fraction suggest the probably presence of more than one lectins in this varieties. The amount of total and soluble proteins showed in decreasing order (globulins, albumins, glutelins and prolamins) in all varieties studied, the Br 14 and Br 9 showed the major content of globulin fraction. The eletrophoretic profile SDS-PAGE) of seed protein (flour and fraction), showed that eletrophoretic pattern of flour was extremely homogeneus for all varieties, although the eletrophoretic paterns of fractions permited to stablish some differences among varieties principaly in the albumin fraction. Finaly the amino acids compositions showed a very similar pattern in flour and fraction, characterized by a high content of acid and hidroxilic amino acid and a very low content of sulfur amino acid like methionine and cysteine.