Composition and antioxidant and antifungal activities of the essential oil from Lippia gracilis Schauer

In this study, the oil constituents of Lippia gracilis were identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antioxidant and antifungal activities were also evaluated. The leaf oil showed a yield of 3.7% and its main constituents were thymol (70.3%), p-cymene (9.2%), thymol methyl ether (5.4%) and p-methoxythymol (2.7%). The thin stem oil showed a yield of 0.4% and its major components were thymol (70.1%), thymol methyl ether (4.4%), p-methoxythymol (4.0%), p-cymene (3.8%), α-humulene (2.4%) and (E)-caryophyllene (2.1%). The aromatic monoterpenes found in the oils showed an average of 88%. The scavenging activity of the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) for the leaf oil, expressed as half maximal effective concentration (EC50), was 35.7±3.3 µg/ml, indicating high antioxidant activity. The evaluation of fungicide activity for the leaf oil, using direct bioautography, showed also a significant value for lethal concentration (LC50 5.0 μg/ml) against Cladosporium sphaerospermum and C. cladosporioides fungi. Keywords: Essential oil composition, thymol and carvacrol, DPPH radical scavenging and bioautographyAfrican Journal of Biotechnology, Vol 13(30) 3107-311

Chemical Variation in the Volatiles of Copaifera reticulata Ducke (Leguminosae) Growing Wild in the States of Para and Amapa, Brazil

The oleoresins of 12 trees of Copaifera reticulata growing wild in the States of Para and Amapa were examined by GC-FID and GC/MS. The majority oleoresins from Para possessed high amounts of P-bisabolene (18.4-42.4%) and trans-alpha-bergamotene (11.8-29.6%). The oleoresins from Amapa were rich in beta-caryophyllene (27.8-68.0%), beta-selinene (0.2-20.6%) and beta-bisabolene (3.7-17.8%). The results showed a high variation in the composition of the components of the oleoresins of C. reticulata.216501503Dendrogene Project (Embrapa/DFID)FUNTEC/P

Variation in volatiles of Ocimum campechianum Mill. and Ocimum gratissimum L. cultivated in the North of Brazil

The essential oils of seven samples of Ocimum campechianum and five samples of O. gratissimum cultivated in the state of Para were obtained by hydrodistillation and analyzed by GC and GC-MS. The most abundant components identified in the leaf oils from O. campechianum were: eugenol (32.2% - 60.6%), methyleugenol (60.6% - 69.5%),1,8-cineole (0.9% - 19.7%), and elemicin (0.2% - 65.9%). The most abundant components identified in the oils from 0. gratissimum were: thymol (13.1% - 36.2%),7-terpinene (0.2% - 28.1%),1,8-cineole (0.0 - 25.2%), and p-cymene (4.4% - 19.9%). The results reveals the occurrence al least four types of O. campechianum in the State of Para, and at least two types of O. gralissimum. The O. gratissimum studied,are belongs to variety macrophyllum.10322924