Ronaldo Adelfo Wasum

Estudo do óleo essencial de algumas espécies do gênero Baccharis (Asteraceae) do sul do Brasil

About 15% of the known Baccharis species have been phytochemically studied, but few studies regarding their essential oils have been reported. The present work aims to identify native species of the State of Rio Grande do Sul, and to evaluate their aromatic potential. Twelve samples were collected in different sites within the State. The essential oils were obtained by an one hour hydrodistillation in a Clevenger apparatus, using plant materials dried for four days at 30°C. The GC analyses were carried out with a HP6890 Series apparatus, equiped with a HP-Chemstation data processor and an HP-Innowax column. The GC/MS analyses were carried out with an HP 6890/MSD5973, equiped with an HP Chemstation and a Wiley 275 spectra library, using the same column as above. The best yield was those of B. articulata (0.5% v/w). b-Pinene was identified as the main component in the samples from B. articulata (41.4% to 52.8%) and from B. cogata (27.2%). Spathulenol was present in the samples from B. semiserrata (15.5% and 25.5%) and those from B. uncinella (47.7% and 23.1%). B. oxyodonta showed limonene (24.3%). Two samples of B. milleflora had spathulenol as main component, but a third one had b-pinene as main constituent.

Essential oil composition of south Brazilian populations of Cunila galioides and its relation with the geographic distribution

Abstract Air-dried samples of 20 Brazilian populations of Cunila galioides were extracted by steam distillation and analyzed using GS and GS–MS. A total of 40 volatile compounds were detected and identified. Fourteen compounds were presented in high concentration, (>10% of the essential oils) in at least one of the populations, and were used to analyze the relationship between the populations. Three affinity groups, which can be considered as chemotypes, were formed by the average linkage cluster analysis. The citral group was characterized by high concentrations of neral and geranial (28 ± 1.49% and 40.5 ± 1.73%, respectively), the ocimene group by high concentration of trans-β-ocimene (33.05 ± 2.54%), and the menthene group by the presence of 1,8-cineole (10.69 ± 2.93%), trans-p-2,8-menthadiene-1-ol (11.46 ± 1.54%), 1,3,8-menthatriene (10.39 ± 1.41%), and 1,5,8-p-menthatriene (7.75 ± 2.32%), as their main constituents. Geographically, the chemotypes containing citral originated from the northeast plateau of Rio Grande do Sul, whereas chemotypes containing ocimene originated from the grasslands of high altitudes of the Atlantic range, and those of the menthene group were found in a transition area between the two regions. The chemovariation observed appear to be genetically determined.

Análise de taninos totais em plantas aromáticas e medicinais cultivadas no Nordeste do Rio Grande do Sul

Tannins are polyphenolic compounds present in plants which are also found in foods and beverages. They are specially used by pharmaceutical, food, leather and rubber industries, and also for water treatment. Considering the significance of this group of compounds, several of aromatic and medicinal plants cultivated in Northern Rio Grande do Sul State, Brazil, were tested for their total tannin content. Angelica archangelica , Cinnamomun camphora var. linaloolifera fugita , Cymbopogon citratus, Lavandula dentata , Lippia alba, Rosmarinus officinalis and Thymus vulgaris were analysed and compared with Acacia mearnsii (black wattle) which is industrially used for tannin extraction. The extraction procedure was made by macerating the plants in methanol, and the quantification was done using Folin Denis reagent and spectrophotometry. By using a calibration curve (% tannic acid equivalent) the total tannin contents range from 0.01% ( Cymbopogom citratus ) to 18.9% ( Lippia alba ).

Analysis of the Essential Oil Composition of Cunila galioides Benth.

Abstract Essential oils, hydrodistilled from the leaves and flowers of Cunila galioides Benth. collected in Rio Grande do Sul and Santa Catarina, Brazil, were analyzed by GC and GC/MS. The main compounds in the oil of flowering plants of sample A were geranial (44.3%), neral (33.6%) and geranyl acetate (5.2%). In sample B, (E)-β-ocimene (46.6%), geranial (10.3%), linalool (9.3%) and neral (7.5%), were the main constituents.

Mosses as indicators of atmospheric metal deposition in an industrial area of southern Brazil

Caxias do Sul hosts the second largest metal-mechanic pole in Brazil, which increases the risk of atmospheric contamination. With the aim of identifying species that might be useful as indicators of atmospheric deposition of metals, 15 species of mosses from an urban and a rural setting were analyzed and compared with specimens deposited at the Herbarium of the Universidade de Caxias do Sul. Metal concentrations (Zn, Ni, Cd, Cr, Cu and Pb) were determined using Atomic Absorption Spectrometry (AAS). The Mann-Whitney test indicated concentrations of Zn, Cu, Pb and Cr that were significantly different between the urban and rural areas. Additionally, Concentrations of Zn, Cd, Cu and Pb were significantly higher in recently collected samples. The species Thuidium tomentosum Besch., Sematophyllum subpinnatum (Brid.) E. Britton, Helicodontium capillare (Hedw.) A. Jaeger, Schlotheimia jamesonii (W.-Arnott) Brid. and Meteorium deppei (Hornsch. ex Mull. Hal.) Mitt. are potential biomonitors of atmospheric metal deposition.

Avaliação do óleo essencial de Aloysia sellowii (Briquet) moldenke (Verbenaceae) do Sul do Brasil

This work was performed with the aim of evaluating the chemical variability among samples of Aloysia sellowii (Verbenaceae) collected in different geographical regions as well as the application of supercritical CO2 for obtaining essential oil. Thus, samples were collected in different localities and oils were isolated by hydrodistillation and supercritical CO2. Results showed existence of two chimiotypes in the species (cineole and sabinene). The supercritical CO2 extraction process was appropriate for extraction of A. sellowii essential oil at 40 oC, 110 bar, 2 mL/min of flow and 10 min of extraction time.