RESUMO: "Análise de uma própolis verde brasileira da Baccharis dracunculifolia por CLAE-ICPA-EM e CG-EM". Os extratos em etanol e diclorometano de uma própolis verde de Baccharis dracunculifolia foram analisados por CLAE-ICPA-EM e CG-EM, respectivamente. A técnica de CLAE-EM-ICPA, no modo positivo, forneceu uma completa e inequívoca composição química da amostra de própolis verde. Ela serve como impressão digital para amostras diferentes de própolis. A composição do extrato em etanol consistiu fundamentalmente de ácido cinâmico e derivados, fl avonóides, ácido benzóico e alguns benzoatos, aromáticos não hidroxilados, e ácidos e ésteres alifáticos, os quais são normalmente ignorados na literatura porque não absorvem luz UV. Os constituintes principais do extrato em diclorometano foram compostos prenilados, alcanos e terpenóides. Unitermos: Baccharis dracunculifolia, Asteraceae, própolis, própolis verde, CLAE-EM-IQPA, CG-EM.ABSTRACT: Ethanol and dichloromethane extracts of a Brazilian green propolis from Baccharis dracunculifolia were analyzed by HPLC-APCI-MS and GC-MS, respectively. The HPLC-APCI-MS technique, at the positive mode, furnished a complete and unequivocal chemical composition of the green propolis sample. It serves as fi ngerprint for different propolis samples. The composition of the ethanol extract consisted mainly of cinnamic acid and derivatives, fl avonoids, benzoic acid and a few benzoates, non-hydroxylated aromatics, and aliphatic acids and esters, which are normally not reported in the literature because they do not absorb UV light. The main constituents of the dichloromethane extract were prenylated compounds, alkanes and terpenoids.
Stress Corrosion and Static Fatigue of Glass," J . Arner. Cerarn. SOC., 53 [lo] 543-48 (1970). l4 V. R. Regel and A. M. Leksovsky, "Study of Fatigue Within the Framework of the Kinetic Concept of Fracture," Int.The dc conductivity of natural single-crystal a-Fe,Qa was measured as a function of 0, partial pressure from lo-* to l atm at 950" to 1422°C. The conductivity was independent of 0, partial pressure, indicating that hematite is an intrinsic semiconductor with lattice defect concentrations much lower than the concentration of intrinsic electrons (holes). The activation energy of the dc conductivity was 1.18 eV. The iron tracer (55Fe) diffusion coefficients, measured as a function of 0, partial pressure a t 1200" and 1300°C, increased as the 0, partial pressure decreased, with a pressure dependence of -0.75; the iron therefore migrates interstitially.
Compostos bioativos e atividade antioxidante do Café Conilon submetido a diferentes graus de torra sérgio antônio lemos de morais, francisco José tôrres de aquino * , priscilla mendes do nascimento, evandro afonso do nascimento e roberto Chang Instituto de Química, Universidade Federal de Uberlândia, CP 593, 38408-100 Uberlândia -MG, BrasilRecebido em 19/2/08; aceito em 10/10/08; publicado na web em 5/2/09 BIOACTIVE COMPOUNDS AND ANTIOXIDANT ACTIVITY OF CONILON COFFEE SUBMITTED TO DIFFERENT DEGREES OF ROASTING. The bioactive compounds and antioxidant activity presented by Conilon coffee (C. Canephora) variety, produced in the Espírito Santo State, Brazil, were quantified. The light roast coffee showed the highest level of total phenols, trigonelline, caffeic and chlorogenic acids. The proanthocyanidin level was the highest for dark roast coffee, while caffeine level didn't show significative changes for the light and middle roast coffees. All the Conilon coffee extracts showed antioxidant activity depending on bioactive compounds concentration and roasting degree. The coffee samples submitted to a light roasting degree showed the highest antioxidant activity.
RESUMO:Duguetia furfuracea, Annonaceae, uma invasora de pastagens, é também usada na medicina tradicional em diversos estados no Brasil. Devido à signifi cante diferença de odor entre dois grupos de indivíduos desta planta em um remanescente de cerrado em Campo Grande, Mato Grosso do Sul, seis amostras foram selecionadas de acordo com a intensidade de odor em suas folhas: In-01, In-03 e In-05: odor pronunciado (Perfi l A); In-02, In-04 e In-06: odor fraco ou ausência de odor (Perfi l B). As folhas foram coletadas e submetidas a hidrodestilação para obtenção dos óleos essenciais, os quais foram analisados por CG/EM. Uma boa compatibilidade foi encontrada entre os resultados obtidos por CG/EM e a análise olfativa adotada para as amostras: espécimes odor pronunciado apresentaram uma alta porcentagem de monoterpenos e alguns sesquiterpenos: In-01 ( -felandreno, 42,2%; mirceno, 6,8%; -felandreno, 4,6%); In-03 (terpin-4-ol, 21,6%; sabineno, 17,3%; p-cimeno, 5,6%); In-05 (sabineno, 25,1%; terpin-4-ol, 16,2%; pcimeno, 8,3%). Apenas sesquiterpenos foram encontrados nos espécimes que apresentaram odor fraco ou ausência do mesmo (com constituinte majoritário biciclogermacreno: 21,4%, 24,0%, and 29,1%, respectivamente, para os In-02, In-04 e In-06).Unitermos: Duguetia furfuracea, Annonaceae, óleo volátil.ABSTRACT: "Chemical variability of the essential oil of the leaves from six individuals of Duguetia furfuracea (Annonaceae)". Duguetia furfuracea, Annonaceae, a pasture weed, is also used in folk medicine in several Brazilian states. Because of the signifi cant difference in odor between two groups of this plant in a remnant patch of savanna in Campo Grande county, Mato Grosso do Sul, six samples were selected according to the odor intensity in the leaves (In-01, In-03, and In-05: pronounced odor; In-02, In-04, and In-06: weak odor or its absence). The leaves were collected and subjected to steam distillation for extraction of essential oils, which were analyzed by GC-MS. A good agreement was found between CG/MS results and olfactory evaluation of the samples: specimens exhibiting leaf scent had a high percentage of monoterpenes and some sesquiterpenes, as follows: In-01 ( -phellandrene, 42.2%; myrcene, 6.8%; -phellandrene, 4.6%); In-03 (terpin-4-ol, 21.6%; sabinene, 17.3%; p-cymene, 5.6%); 25.1%; 16.2%; 8.3%). Only sesquiterpenes were found in the specimens having weakly scented or scentless leaves (main constituent bicyclogermacrene: 21.4%, 24.0%, and 29.1%, respectively, for In-02, In-04 and In-06).
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