Extracts from the leaves of Piper piscatorum (Trel. Yunc.) obtained by supercritical extraction of with CO2, employing ethanol and methanol as co-solvents

The efficiency of the extraction of fresh and dried leaves of Piper piscatorum was evaluated employing supercritical CO2 and co-solvents (10% ethanol and 10% methanol) at 40 °C and 70 °C and a pressure of 400 bar. The extracts were characterized chemically by GC–MS and GC–FID. The major components of the extracts were piperovatine, followed by palmitic acid, pentadecane and pipercallosidine. Drying of the leaves caused modifications in their composition, mainly reducing the concentration of the amides, which have activity as anesthetics. The highest yields of the piperovatine (0.93%, w/w) and pipercallosidine (0.24%, w/w) were obtained from the fresh leaves extracted with CO2 modified with 10% ethanol at 40 °C

Influência da temperatura de secagem sobre o rendimento e a composição química do óleo essencial de Tanaecium nocturnum (barb. Rodr.) bur. & K. Shum

The yields and chemical compositions of the essential oils obtained by steam distillation of the fresh and dried (30 and 40 ºC) leaves, stems and roots of Tanaecium nocturnum are reported. The identification and quantification of the volatile constituents were accomplished by GC/MS and GC/FID, respectively. The essential oils obtained from the various parts of the plant were constituted mainly of benzaldehyde. Large losses and variations in the quantities of the components during the drying process were observed. The presence of mandelonitrile in higher concentration in the stem and roots indicates that this species produces cyanogenic glycosides