Comparação Mensal da Composição Química e das Constantes Físicas do Óleo resina e essencial de Copaifera reticulata Ducke e C. martii Hayne

Abstract

Copaiba oil, extracted from the trunk of species of the genus Copaifera (Leguminosae), consists mainly of sesquiterpenes, and is widely used in traditional medicine in the Amazon region. The commercial copaiba oil is preferably stored in amber glass bottles, due to its instability. Aiming to determine the stability of the oil-resin of two species of Copaifera: C. reticulata and C. martii, commonly found in Pará, the phytochemical properties and chemical composition of the resin oils and the essential oils obtained from them were monitored for one and a half years. The resin oils, extracted with an auger, were stored in amber and colorless glasses at room temperature. The relative density was measured in a pycnometer, the viscosity in a Haake viscometer, the refractive index in an Abbé refractometer, and the essential oil content by hydrodistillation. The chemical components were analyzed by gas chromatography, using a DB5-MS capillary column, temperature program: 60° C 240°C (3°Cjmin), with injector and detector at 250°C. The data obtained indicated significant differences regarding the chemical composition of the oils packed in amber glass when compared to those packed in colorless glass, obtaining the following average values: viscosity: C. reticulata (amber: 25.43 mP.s; white: 26.OOmP.s), C. martii (amber: 8916.67 mP.s; white: 9981.67mP. s), refractive index: C. reticulata (amber: 1.4996; white: 1.5019), C. martii [amber: 1.5144; 1.5150: white), relative density: C. reticulata (amber: 0.9725; white: 1.010), C. martii (amber: 1.0148; white: 1.0734), percentage of essential oil: C. reticulata (amber: 69.46; white: 67.74), C. martii (amber: 24.92; white: 25.68). The main chemical constituents of the resin oils of C. reticulata were ~- bisabolene, trans-a-bergamotene, and ~-selinene, and, those of C. martii a diterpene, B-btsabolene, and o-copaene. The data obtained indicated that the quinque cornposrcation of the resin oils from C. reticulata conditioned in an amber bottle remained without significant variation during the period of the experiment, while in the colorless bottle the percentage of p-caryophyllene was reduced from 5.2% to 0.7%. With respect to C. martii, it was observed that there was no significant variation in the oils stored in the two bottles (amber and colorless).