Estudo fitoquímico e alelopático do extrato de caule de Pterodon emarginatus (Sucupira branca)

Abstract

In order to evaluate the allelopathic potential of the white sucupira ( Pterodon emarginatiis ) aqueous Solutions froni the dry matter of the stem have been done in the concentration o f 25, 50, 75, 100, 150, 200, 300 and 400 ppm. These Solutions were used against seeds of colonião grass (Panicum maximum), in experiments of germination in petri dishes and in green house . The achieved result of these experiments had the purpose to verify that the aqueous extract of the stem of the white sucupira has allelopathic effects in the germination ofthe seeds, and in the development ofhypocotile and root o f grass. Alter the allelopathic effect has been confirmed, the extract was fractioned by filtration in a glass column packed up with silica gel, resulting in an amount o f eight fractions with different polarity. Aqueous Solutions were prepared with the ífactions in concentration o f 200 ppm and it has been used in germination experiments in petri dishes. In the concentration o f 200 ppm, a satisfactory allelopathic result in colonião grass was achieved in two fractions. These two active ífactions were submited to separation in glass columns Chromatography , creating an amount of thirteen subfractions. These subfractions were tested as describe above (200 ppm). The subfraction with the best allelopathic result in the experiments of germination was investigated by IVTF and CG-EM. Seven components were identified in this subfraction :2-methylpentan-l-ol,4-methylpent-3-en-2-ona,l,2,4-trimethyilbenzene,Acid hexadecanoic,(E)-3,7, ll,15-tetramethylexadec-2-en-l-ol, (9E, 12E)-octadeca-9,12-dienolate of methyl and acid (E)- octadec-9-enoic