Copaiba is one of the most used native trees in the Amazon region due to its great
pharmacological potential. The oleoresin produced by copaiba is widely used for
medicinal purposes having a number of proven biological activities, including
antitumor. Cancer is the second most deadly disease in Brazil, and the investigation
of the antitumor potential of copaiba oil is an alternative for the formulation of new
drugs to combat this disease. Thus, the objective of the present work was to evaluate
the chemical composition and in vitro antitumor activity of Copaifera reticulata Ducke
oleoresin. The oil was collected in the Tapajos National Forest, Belterra-PA. The oil
was fractionated by simple distillation to obtain the volatile and resinous fractions.
Eight concentrations of total oleoresin and its fractions in the MCF7 (breast cancer),
HOS (osteosarcoma), PC3 (prostate adenocarcinoma) and H1299 (lung carcinoma)
and in the leukemic lineages were used to evaluate anti-tumor activity in vitro.: Nalm
6 (leukemia B) and Jurkat (T-leukemia), by the MTT-Method 3- (4,5-dimethyl-2-
thiazole) -2,5-diphenyl-2-H-tetrazolium bromide salt. The determination of IC 50
(inhibitory concentration capable of causing 50% of the maximum effect) was
performed through non-linear regression by the Origin 8.0 software and the graphs
generated by the GraphPad Prism 2007 Software. The chemical composition of the
oleoresin was analyzed by Gas Chromatography coupled to Spectrometry and the
identification of compounds by comparison of their mass spectra (MS) and the
retention index (IR) with the data available in the NIST library version 2.0, ADAMS,
2007 and in the literature. In the analysis of the chemical composition of the C.
reticulata oleoresin, twenty six sesquiterpenes and six diterpenes were identified,
corroborating with the works available in the literature on the chemical composition of
the oil of species of the Copaifera genus, where the highest percentage of
substances belong to the class sesquiterpene. The crude oleoresin and its volatile
and resinous fractions presented cytotoxicity to the tested carcinogenic strains, thus
proving the anticancer potential of C. reticulata Ducke oil. Among the samples
studied, the resinous fraction (FR) was highlighted because it presented the lowest
IC50, where in the lower concentrations of RF, it inhibited 50% of the viability of the
neoplastic cells tested. In the quantification of apoptosis of the lineage most sensitive
to treatments (H1299-lung carcinoma), the resinous fraction showed a higher
percentage of induction to cell death.
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