No abstract

RESUMO:A óleo-resina de copaíba pode ser extraída de forma sustentável do tronco de várias espécies de Copaifera. Ela contém principalmente ácidos resinosos e substâncias voláteis, tendo ampla utilização medicinal. A padronização cromatográfi ca do óleo é a garantia da identidade desta matéria-prima complexa. Neste trabalho analisaram-se por CG três amostras de óleos de copaíba obtidas de Colombo/PR e doze amostras adquiridas no Estado do Amazonas. O óleo de copaiba foi fracionado por cromatografi a em sílica gel impregnada com KOH e metilado e as frações obtidas foram avaliadas por CG. Numa segunda etapa, os óleos brutos metilados por meio de diazometano ou transesterifi cados com KOH/MeOH foram injetados diretamente em CG. Foram utilizados para comparação os ácidos diterpênicos hardwíckiico, copaiferólico e caurenóico além do sesquiterpeno 14-hidroxi-β-cariofi leno (cariofi lenol). A presença do ácido copaiferólico foi observada em 100% e cariofi lenol em 80% das amostras. Os ácidos caurenóico e hardwíckiico ausentes nas amostras do Paraná, foram detectados em 8,3% e 41,7% respectivamente nas amostras do Amazonas. Os resultados obtidos indicam que podem ser analisados diretamente através de CG após metilação com diazometano, sem necessidade de fracionamento prévio. Adicionalmente, a determinação do índice de acidez para óleos de copaíba não demonstrou resultados inequívocos para as amostras analisadas.Unitermos: Copaifera, óleo de copaíba, cromatografi a gasosa.ABSTRACT: "Copaiba oil-resin analysis: contribution to quality control". Copaiba oil can be extracted from the trunk of some Copaifera species and contains mainly resinous acids and volatile substances, which have wide medicinal use. The chromatographic standardization of the oil characteristics is the guarantee of the identity of raw material. In this work, three copaiba oil samples from Colombo/PR, and twelve from Amazonas State were analyzed. The copaiba oil was fractionated in silica gel impregnated with KOH, esterifi ed and the fractions were evaluated by TLC and GC. In a second stage, the crude oil was esterifi ed with diazomethane or transesterifi ed with KOH/MeOH and injected in GC. The diterpene acids used for comparison were hardwickiic, copaiferolic and caurenoic and the 14-hydroxy-β-caryophyllene (caryophyllenol). The presence of copaiferolic acid was observed in all analyzed samples and caryophyllenol in 80% of the samples. Hardwickiic and caurenoic acids were absent in the samples from Paraná State, and respectively detected in 8.3% and 41.7%, of the samples from Amazonas. The obtained results indicate that the oil can be directly analyzed through GC after methylation with diazomethane, without previous fractionation. Also, an acidity index method proposed for copaiba oil analysis did not show to be reliable for the analyzed samples.

No abstract

The essential oils of four Guarea species collected at Manaus (Amazonas, Brazil) were obtained by hydrodistillation and analyzed by GC-MS. Except for one diterpene detected, the compounds identified in the essential oils were hydrocarbons and oxygenated sesquiterpenes. The major sesquiterpenes were α-santalene (26.26%) and α-copaene (14.61%) from G. convergens branches; caryophyllene epoxide (40.91%) and humulene epoxide II (14.43%) from G. humaitensis branches; cis-caryophyllene (33.37%) and α-trans-bergamotene (11.88%) from G. scabra leaves; caryophyllene epoxide (36.54%) in leaves and spathulenol (14.34%) in branches from G. silvatica. The diterpene kaurene (15.61%) was found in G. silvatica leaves. Larvicidal activity assay of essential oils against third-instar Aedes aegypti larvae revealed that at higher concentrations (500 and 250 μg/mL), all the essential oils caused 100% mortality after 24 h of exposure. The most active essential oils were those of G. humaitensis branches (LC50 48.6 μg/mL), G. scabra leaves (LC50 98.6 μg/mL) and G. silvatica (LC50 117.9 μg/mL). The differences in the toxicity of essential oils of Guarea species on A. aegypti are due to qualitative and quantitative variations of the components, therefore the larvicidal effect may be due to higher amount of the sesquiterpenes with caryophyllane skeleton.

RESUMOO extrato obtido em metanol da polpa de frutos Endopleura uchi foi submetido a fracionamento utilizando-se técnicas cromatográficas convencionais levando ao isolamento de bergenina. Na análise da composição dos carotenóides foi evidenciada a predominância de β-caroteno (16,57 μg.g -1 ). Os isômeros do β-caroteno foram detectados, trans-β-caroteno (89,3%), 13-cis-β-caroteno (8%) e 9-cis-β-caroteno (3%). Considerando a importância do papel nutricional dos carotenóides e a bioatividade do glicosídeo bergenina, esse estudo sugeriu o potencial desse fruto como alimento funcional. PALAVRAS-CHAVEEndopleura uchi, Bergenina, β-Caroteno. Identification of bergenin and carotenoids in the uchi (Endopleura uchi, Humiriaceae) fruit ABSTRACTThe extract obtained in methanol from the fruits pulp of Endopleura uchi was fractionated using conventional chromatographic tecniques to isolate bergenin. In the analysis of the composition of carotenoids was evidenced the predominance of β-carotene (16.57 μg.g -1 ). The isomers of β-carotene: trans-β-carotene (89.3%), 13-cis-β-carotene (8%) and 9-cis-β-carotene (3%) were detected. Considering the importance of the nutritional role of carotenoids and the bioactivity of the bergenina, this study suggested the potential of this fruit as functional food.