Caracterização química dos extratos em diclorometano de Origanum majorana L. na inibição de Panicum maximum

Abstract

It were studied the allelopathy potential of the extracts of the root, of the stem and of the leaves of Origanum majorana L., as the inhibition of the germination of seeds of Panicum maximum (grass-colonião), the rehearsal was accomplished in boxes gerbox, with light period of 10 hours and 7 days, with solutions of the extracts diclorometânicos of the root, stem and leaf of O. majorana in the concentrations: 50,100 and 200 ppm, as well as it was made the negative rehearsal (white) with Panicum maximum for analysis of the results. The inhibition increased substantially with the increase of the concentration of the extracts, and the extracts of the root, stem and leaf of O. majorana presented inhibition of 100% of the germination in the concentration of 200 ppm. The extract of the root presented inhibition of 80% of the germination in the concentration of 100 ppm and the extract of the leaves of O. majorana presented efficiency of 83% in the inhibition of the root and aerial part, even in the lowest concentration (50 ppm). The extract of the stem was also shown efficient inhibiting 80% of the root and aerial part in the concentration of 100 ppm. Later they were classified the present secondary metabólitos in the root, stem and leaves, of the species in study for thin layer chromatography (TLC), in the root were identifying: flavonoids, triterpenes, steroids and polyphenols. In leaves and stems were identifying: flavonoids, anthraquinone anglicones, triterpenes, steroids, tanines and polyphenols. The active extracts were analyzing through gas chromatography coupled mass spectrum, identifying: beta-farnesene, delta-decalactone and lactone of acid 5-hidroxy- 2-decenoic.