This work describes the evaluation of the antioxidant activity in the system b-carotene / linoleic acid and radical scavenging effects of the substances 2',4'-dihydroxychalcone, 2',3,4,4'-tetrahydroxychalcone (butein), 4-methoxy-2',3,4'-trihydroxychalcone, 7-hydroxyflavanone, 3',4',7-trihydroxyflavanone (butin), 7,4'-dihydroxyflavanone (liquiritigenin), 6-methoxy-7- hydroxydihydroflavonol and lasiodiplodin isolated of the extract CHCl3 of the stem of Dioclea violacea and 3',4',5,7-tetrahydroxyflavanol (quercetin), 4',7- dimethoxy-3',5-dihydroxyflavanol and epicatechin isolated of the Erythroxylum nummularia leaves. These compounds were evaluated and compared with the antioxidant standards n-propyl gallate, BHT and á α-tocoferol.

Espécies nativas ou endêmicas do semi-árido brasileiro foram investigadas com o intuito de se descobrir novas drogas antimicrobianas. Os ensaios foram realizados contra cepas padrões de Staphylococcus aureus e Escherichia coli através do método de difusão em disco. Dos 137 extratos de vegetais avaliados, sete apresentaram atividade significativa contra o Staphylococcus aureus. Os extratos ativos foram preparados a partir de espécies pertencentes às famílias Leguminosae e Rutaceae e serão futuramente fracionados com o intuito de se chegar às moléculas ativas.

Species native or endemic of the Brazilian semi-arid were investigated with the intention of discovering new antibacterial drugs. The rehearsals were accomplished against standard strains of Staphylococcus aureus and Escherichia coli through the diffusion method in disk. Of the 137 extracts of appraised vegetables, seven presented significant activity against the Staphylococcus aureus. The active extracts were prepared starting from species belonging to the Leguminosae and Rutaceae families and they will be fractional hereafter with the intention of arriving to the active molecules.