Roselaine Facanali

Phytochemical characterization of essential oil from Ocimum selloi

Ocimum selloi Benth, a native plant of Brazil, has medicinal uses as anti-diarrheic, antispasmodic and anti-inflammatory product. The yield of essential oils of the inflorescences, containing flowers and seeds, was 0.6%, and the yield of leaves, collected in two different seasons, was 0.25% (June 2000) and 0.20% (January 2001), respectively. The essential oils of the inflorescences and leaves presented as major constituents trans-anethol (41.34%, 45.42%, 58.59%) and methyl chavicol (27.10%, 24.14%, 29.96%).

Chemical Composition and Larvicidal Activity against Aedes aegypti Larvae of Essential Oils from Four Guarea Species

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.

Composição química e modulação da resistência bacteriana a drogas do óleo essencial das folhas de Rollinia leptopetala R. E. Fries

The essential oil from the leaves of Rollinia leptopetala was obtained by hydrodistillation in Clevengers apparatus and its chemical composition was analyzed by GC-MS. With this technique could be identified 22 constituents in a complex mixture of monoterpenes (54.5%) and sesquiterpenes (45.5%). The main component found in the leaves was the bicyclogermacrene (22.47%). The essential oil was assayed against a strain of Staphylococcus aureus possessing efflux mechanism of resistance to norfloxacin. Although the essential oil did not display relevant antibacterial activity in vitro, it modulated the activity of the norfloxacin, i.e. in combination with the antibiotic it was observed a fourfold reduction in the minimum inhibitory concentration for norfloxacin, indicating inhibition of efflux pump.

Cultivo de manjericão em hidroponia e em diferentes substratos sob ambiente protegido

Among the aromatical herbs, basil is of great economic importance in Brazil. This species is used as fresh herb and also for essential oil extraction. To evaluate the productivity of basil in protected environment, two species, Ocimum minimum L. (narrow leaf basil) and Ocimum basilicum L. (wide leaf basil) were cultivated under greenhouse conditions, using a hydroponic system and two types of substrata. The experiment was carried out in a completely randomized design with three repetitions. Samples were obtained during the flowering period. The yield and the chemical composition of the essential oils were evaluated. The highest yield of green mass from the two species, was obtained in the hydroponic system, with higher productivity (aprox. 44%) than the plants cultivated in prepared commercial substratum. Plants of Ocimum minimum L. produced more essential oil (aprox. 10%) than plants of Ocimum basilicum L. Significant differences were found in the chemical composition of essential oil between species. No differences were observed in the chemical composition of essential oil, comparing the three cultivation systems.

Non-Oxygenated Sesquiterpenes in the Essential Oil of Copaifera langsdorffii Desf. Increase during the Day in the Dry Season

The present study aimed to evaluate the effect of seasonal and diurnal events on the chemical profile of the essential oil obtained from the leaves of Copaifera langsdorffii Desf. This study was performed in a Brazilian savanna named Cerrado. We identified the best harvesting period for obtaining the highest amount of compounds used for commercial and industrial purposes. The chemical profile of the essential oils was evaluated by GC-FID and GC-MS, and the results were assessed through multivariate analyses. The data showed that the time of day and seasonal variations affect the quality of the essential oil obtained. Leaves harvested at the end of the day (5:00 pm) in the dry season resulted in richer essential oils with higher amounts of non-oxygenated sesquiterpenes. To the best of our knowledge, environmental conditions induce metabolic responses in the leaves of C. langsdorffii, which changes the patterns of sesquiterpene production. Therefore, these factors need to be considered to obtain better concentrations of bioactive compounds for pharmacological studies.

Chemical constituents of essential oil of Protium decandrum (Burseraceae) from Western Amazon.

Abstract The chemical composition of essential oils obtained from the leaves (leaflets and rachis), branches and resin of Protium decandrum (Aubl.) Marchand, Burseraceae, growing in the Amazon forest were examined by GC-MS. The oils extracted from leaves showed varying content of tenpin-4-ol (rachis: 64.8 %; leaflets: 33.0 %). The sesquiterpene trans-α-bergamotene was the major component identified in the oil from branches (22.1 %) and resin (47.7 %).

Composition and Antimicrobial Activity of the Leaf Essential Oils of Duguetia gardneriana Mart. and Duguetia moricandiana Mart. (Annonaceae)

Abstract As part of their continuing studies on the constituents of the genus Duguetia, these authors have studied the composition and antimicrobial activity of the essential oils obtained from the leaves of two species, and the results are reported here. A hydrodistilled oils obtained from the leaves of Duguetia gardneriana and Duguetia moricandiana were analyzed by GC/MS. The oils showed a total of 33 components. Germacrene D (28.1%), viridiflorene (24.0%), β-pinene (12.6%), α-pinene (9.1%) and β-caryophyllene (5.6%) were found to be the major individual constituents of D. gardneriana oil. The leaf oil of D. moricandiana was dominated by germacrene D (44.3%), α-pinene (13.0%), viridiflorene (9.3%), β-pinene (9.2%) and β-caryophyllene (6.8%). The oils were tested for their antimicrobial activity against 11 pathogenic microorganisms using standard gel diffusion method. The essential oil of D. gardneriana showed activity against Staphylococcus aureus and Candida guilliermondii, while the essential oil of D. moricandiana was more active against Staphylococcus aureus and Candida albicans.

Dry and wet seasons set the phytochemical profile of the Copaifera langsdorffii Desf. essential oils

Dry and wet seasons present in different formations on the Cerrado domain are capable of promoting alterations in the composition of volatile compounds (terpenes) in the essential oil from copaiba (Copaifera langsdorffi Desf.). Different ecophysiological conditions of regions and climatic change could be important factors in modifying the chemical profile of terpenes and the yields from essential oil. Copaiba plants from semideciduous seasonal forests show differences into the phytochemical profile obtained in dry and wet seasons, with presence of monoterpenes alpha-thujene, o-cymene, (Z)-beta-ocimene, (E)-beta-ocimene, gamma-terpinene and terpinolene in point 1 (in the wet season), while Cerrado strictu sensu did not show significant differences in chemical composition of volatile compounds (only alpha-cadinol and seychellene showed significant differences). Nevertheless, sesquiterpenes trans-caryophyllene, gamma-cadinene, delta-cadinene, germacrene B and the oxygenated sesquiterpene caryophyllene oxide did not shown any significant differences in the essential oil composition among different points, independent of seasonality.

Determinação do perfil de compostos voláteis e avaliação do sabor e aroma de bebidas produzidas a partir da erva-mate (Ilex paraguariensis)

Volatile compounds from green and roasted yerba mate were analyzed by gas chromatography/mass spectrometry and the flavor profile from yerba mate beverages was determined by descriptive quantitative analyses. The main compounds tentatively identified in green mate were linalool, a-terpineol and trans-linalool oxide and in roasted mate were (E,Z)-2,4-heptadienal isomers and 5-methylfurfural. Green mate infusion was qualified as having bitter taste and aroma as well as green grass aroma while roasted mate was defined as having a smooth, slightly burnt aroma. The relationship between the tentatively identified compounds and flavor must be determined by olfatometric analysis.

Volatiles of Foliar Rachis, Branches and Resin Elicited by Insects from Protium hebetatum Grows Wild in Amazon

Abstract The essential oils extracted from foliar rachis and resin from two trees of Protium hebetatum (resin: tree A; foliar rachis and branches: tree B) were extracted by hydrodistillation and examined by CG-MS. The trunk wood resin of the tree A, released by the action of the insects, was extracted during one hour (Sample A) and for more three hours (Sample B). Both resin oils obtained were characterized by the predominance of monoterpenes, among them, p-cymene (35.8 %; 38.9 %), cis-β-dihydroterpineol (10.0 %; 3.2 %), limonene (9.0 %; 11.7 %), α-pinene (8.7 %; 20.3 %), and α-phellandrene (3.5 % 8.1 %). α-Pinene was predominant only in the branches (14.6 %) while α-cubebene (5.6 %; 9.2 %), α-copaene (8.3 %; 11.7 %), β-caryophyllene (12.8 %; 9.1 %) and caryophyllene oxide (23.3 %; 15.4 %), respectively, were found in major amount in foliar rachis and branches. We agree that the great amount of resin that was observed in the trunk wood of the tree A could be justified by the association of insects producing a continuous exudation.