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

Abstract

Copaiba (Leguminosae, genus Copaifera L) is a tree that can reach up to 36 m in height, well known in the American continent for producing a resinous oil of great medicinal and commercial importance, known as "copaiba oil", which can be easily found throughout the Amazon region, where it is sold in markets and pharmacies, and is used by the Amazonian populations mainly as a bactericide, cicatrizant, and anti-inflammatory. Several compounds found in copaiba oil have already had their pharmacological properties described in the literature. These oils are quite unstable and are therefore preferably stored in amber glass bottles. In order to evaluate the variation that occurs in copaiba oils when stored in colorless amber glass bottles at room temperature, we monitored the physical (bimonthly) and chemical (monthly) properties of Copaifera reticulata and C. marti oils for a period of 1 year. The oil was extracted by drilling the trunk of the trees, at a height of approximately 1 m from the ground, and immediately stored in an amber bottle. The density was determined using a 1 mI pycnometer, the refractive index, in an Abbé refractometer, at 40° C; viscosity was measured in a HAAKE Visco tester VT6L viscosimeter. The chemical components of the resin oil and essential oil were identified by GC and GC/MS, using DB-sMS capillary column, temperature program: 60° C - 2400 C (3° C/min) and injector temperature 220° C. The data obtained indicated significant differences in the physical properties of the two species: viscosity (C. reticulata = 30, C. martii = 9075), refractive index (C. reticulata = 1.4897, C. martii= 1.5140), relative density (C. reticulata = 0.9403, C. martii= 1.0269) and in the percentage of essential oil (C. reticulata = 74.6%, C. martii = 24.6%). The main components of the resin oil from the crude specimen of C. reticulata were b-bisabolene (33.6%), trans-a-bergamotene (18.1%) and b-selinene (10.0%). In the oil of C. martii esrudada specimen the main components were: a diterpene (32.3%), b-bisabolene (9.3%), d-cadinene (8.2%) and acopaene (14.0%). In the period studied, no significant variations were observed in the physical properties of the oils of the two species as a function of period and type of storage. The chemical composition of the oils from C. martii did not show significant variation according to the type of storage until the studied period. No variation was observed in the chemical composition of the main components (310.0%) of the C. reticulata oil stored in both jars. However, significant variations were observed in the percentage of b-caryophyllene (from 5.1% to 1.7%) and caryophyllene oxide (from 0.3% to 3.1).