Influência sazonal no óleo essencial da Baccharis articulata e da B. trimera via cromatografia gasosa mono e bidimensional

Abstract

Carquejas belong to the Asteraceae family and the genus Baccharis, but B. articulata (white carqueja) and B. trimera (green carqueja) are the most prominent species in Rio Grande do Sul. Essential oils contribute to the identification of botanical species, a fact that is very useful when dealing with plants of the genus Baccharis, in some cases present botanical description is very similar. The aim of this study was to differentiate two species of the genus Baccharis (green and white carqueja) of the chemical composition of essential oils, considering the seasonal variation in order to diagnose the best time to harvest the plant to obtain the active ingredients. These oils were obtained by hydrodestillation(Clevenger apparatus) and constituents identified via gas chromatography one and two-dimensional. Yields of essential oils extracted from B. articulata and B. trimera in the four seasons were 0.06 and 0.98% (summer), 0.13 and 0.62% (autumn), 0.16 and 0.07% (winter), and 0.03 and 0.23 % (spring), respectively. Gas chromatography one-dimensional allowed to identify 36 compounds in white carqueja is the majority spathulenol (10.3-22.7%) and β-caryophyllene(3.8-9.1%), while the two-dimensional technique showed 84 components identified confirming the sensitivity of GC × GC. Similarly for the green carqueja 19 compounds were detected by GC/MS and 61 by two-dimensional with strong presence of carquejil acetate(41.6-70.9%) and ledol(8.8-22.9%). By linking all data obtained confirmed the direct influence of various factors on chemical composition of plants, especially flowering time that was crucial in this research, thereby affirming the infinite possibility of studies in the area of natural products