Journal of the Brazilian Chemical Society
On-line version ISSN 1678-4790
SIMIONATTO, Euclésio et al. Chemical composition and evaluation of antibacterial and antioxidant activities of the essential oil of Croton urucurana Baillon (Euphorbiaceae) stem bark. J. Braz. Chem. Soc. [online]. 2007, vol.18, n.5, pp. 879-885. ISSN 1678-4790. http://dx.doi.org/10.1590/S0103-50532007000500002.
The essential oil obtained from the stem bark of Croton urucurana Baillon (Euphorbiaceae) was analysed by GC and GC-MS. 83 compounds were identified and borneol (14.7%), bornyl acetate (5.2%), 1-isopropyl-7-methyl-4-methylene-1,3,4,5,6,8-hexahydro-2H-naphthalen-4a-ol (14.7%), sesquicineole (10.5%) and g-gurjunene epoxide (5.4%) were the main components. The EC50 value of the crude essential oil in the DPPH free radical scavenging assay was 3.21 mg mL-1. The fraction of the crude essential oil that presented antioxidant activity was purified by prep-TLC on silica gel. GC and GC-MS analysis revealed that a-bisabolol (38.3%), a-eudesmol (9.3%) and guaiol (8.2%) were the main components of the antioxidant fraction. The EC50 value measured for the bioactive oil fraction in the DPPH assay was 1.05 mg mL-1. The antimicrobial activity of the crude essential oil was assayed against seven Gram-positive and Gram-negative bacteria and three yeasts. Measured MIC values ranged from 1.25 to 10.00 mg mL-1.
Keywords : Croton urucurana; essential oil; antioxidant; DPPH assay; antimicrobial acticity.