ABSTRACT
Coumarin, o-coumaric, and kaurenoic acid are bioactive compounds usually found in the leaves of Mikania laevigata. Genetic and environmental variations in the secondary metabolites of plants may have implications for their biological effects. Three different accessions of M. laevigata cultivated in four sites between the Equator and the Tropic of Capricorn in Brazil were evaluated aiming to present potential raw materials and discuss relationships among these three bioactive compounds. The results revealed effects of plant accessions and environmental factors and suggested two contrasting chemical phenotypes of M. laevigata. The first phenotype presented the highest levels of kaurenoic acid (2283 ± 316 mg/100 g) besides lower levels of coumarin (716 ± 61 mg/100 g), which was also stimulated by the environment and mild climate at the site nearest to the Tropic of Capricorn. The other phenotype presented the lowest levels of kaurenoic acid (137 ± 17 mg/100 g) besides higher levels of coumarin (1362 ± 108 mg/100 g), which was also stimulated by the environment and tropical climate at the site nearest to the Equatorial beach.
Subject(s)
Coumarins/analysis , Diterpenes/analysis , Mikania/chemistry , Coumaric Acids/analysis , Environment , PhenotypeABSTRACT
Foi determinada a composição química dos óleos essenciais de 3 espécies do gênero Piper coletadas em Matas de Galeria no Cerrado, e comparada com composição dos óleos das mesmas espécies oriundas da Mata Atlântica. A composição química do óleo de Piper arboreum subsp arboreum, P. dilatatum e P. hispidum foi determinada por cromatografia gasosa em coluna capilar HP-5 e espectrometria de massas. As três espécies do Cerrado apresentaram predominância de sesquiterpenos. Piper arboreum subsp arboreum apresentou como constituintes majoritários biciclogermacreno (12,1 por cento), 10-epi-g-eudesmol (11,6 por cento) e óxido de cariofileno (10,1 por cento). Em P. dilatatum os constituintes em maior quantidade foram cis-b-ocimeno (19,6 por cento) e b-cariofileno (11,3 por cento) e em P. hispidum foram b-pineno (19,7 por cento), a-pineno (9,0 por cento).
The chemical composition of the essential oils of three species of Piper, namely Piper arboretum subsp arboretum, P. dilatatum and P. hispidum, from the Cerrado (Brazillian savannah) was determined and compared with the composition of the oils from the same species collected in the Atlantic Rain Forest. Analyses were performed by gas chromatography and mass spectrometry using a HP5 capillary column. Sesquiterpenes were the major constituents of the oils. In P. arboreum subsp arboreum, bicyclogermacre (12.1 percent), 10-epi-g-eudesmol (11.6 percent) and caryophyllene oxide (10.1 percent) were the main constituents. For P. dilatatum cis-b-ocimene (19.6) and b-caryophyllene (11.3 percent) were the major compounds. The main components in P. hispidum oil were b-pinene (19.7 percent) and a-pinene (9.0 percent).
