Marcia Regina Pansera

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.

Physico-chemical evaluation of Rosmarinus officinalis L. essential oils

Dezenove amostras de Rosmarinus officinalis foram extraidas por destilacao por arraste a vapor em uma planta piloto e os oleos essenciais foram avaliados quanto a composicao quimica e caracteristicas fisico-quimicas. Os rendimentos de oleo essencial variaram de 0,37% (media de 1999) a 0,49% (media de 1998). Vinte componentes foram identificados nos oleos essenciais. Os componentes majoritarios foram a-pineno (40,55 a 45,10%), 1,8-cineol (17,40 a 19,35%), canfeno (4,73 a 6,06%) e verbenona (2,32 a 3,86%). A media por safra dos parâmetros fisico-quimicos avaliados resultaram em 0,8887g/cm3 para densidade especifica, 1,4689 para indice de refracao e +11,82o para rotacao optica, sendo que as variacoes encontradas para os parâmetros quimicos e fisico-quimicos dos oleos essenciais nao variaram significativamente em funcao do ano de producao.

Seasonal Variation of Essential Oil Yield and Composition of Thymus vulgaris L. (Lamiaceae) from South Brazil

Abstract Essential oils from the leaves of Thymus vulgaris L. collected from Caxias do Sul (Rio Grande do Sul State, Brazil) were isolated by hydrodistillation with an average oil yield of 0.25%. Twenty-two components were identified by GC and GC/MS analysis. Thymol was found to be the most abundant constituent (31.5–52.4%), followed by p-cymene (17.1–34.4%). Thyme possessed a higher oil yield and the oil was richer in oxygenated compounds when harvested in the spring.

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 ).

Essential oil yield and composition of Lamiaceae species growing in southern Brazil

The Lamiaceae family has been described to be rich in essential oil. The aim of the present work was to identify the native species of Rio Grande do Sul with potential use as the aromatic plants. Seven species of the family were collected in the different localities of the state. The essential oils were obtained by 1h hydrodistillation in a Clevenger apparatus. The constituents were identified by comparing their GC Kovats retention indices (RI), determined with reference to a homologous series of n-alkanes and by comparing their mass spectral fragmentation patterns with literature data. Cunila incisa and Mentha aquatica resulted in the higher esssential oil yields (1.94% v/w and 0.93% v/w, respectively. The composition of M. aquatica was 80% methone, with almost 14% pulegone. C. microcephala had 53% menthofuran and C. incisa nearly 45% of 1.8-cineol and 18% α-terpineol.

Extraction of tannin by Acacia mearnsii with supercritical fluids

Studies were carried out on solvent and supercritical extraction to obtain natural tannins. The results showed that the best co-solvent to extract tannin with CO2 supercritical was water with a concentration of 5.0% and the best trap rinse solvent was methanol.

In vitro antifungal activity of four chemotypes of Lippia alba (Verbenaceae) essential oils against Alternaria solani (Pleosporeaceae) isolates

Several volatile natural compounds produced by plant secondary metabolism have been proven to present antimicrobial action, enabling their use in phytopathogen control. They also present low environmental impact when compared to conventional pesticides. Essential oils contain these compounds and can be found in several plant species, such as Lippia alba (Mill.) N.E. Brown (Verbenaceae). Essential oils of four chemotypes of L. alba, characterized by their major compounds, namely camphor, citral, linalool and camphor/1,8-cineole, were tested against the phytopathogen Alternaria solani Sorauer (Pleosporaceae), which causes early blight on tomatoes and is responsible for great economic losses regarding production. Essential oils antifungal action was tested in vitro using potato dextrose agar medium with essential oil concentrations at 0.1, 0.5, 1.0, 1.5 and 2.0 µL mL-1. The chemotype that had the best performance was citral, showing significant inhibition compared to the others, starting at the 0.5 µL mL-1 concentration. The essential oil belonging to the linalool chemotype was efficient starting at the 1.5 µL mL-1 concentration. Conversely, the camphor chemotype did not show any action against the phytopathogen. Moreover, the essential oils had no remarkable effect on tomato germination and growth. In conclusion, these essential oils presented fungicidal action against A. solani.

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.

Detection of antifungal activity of plant extracts on Alternaria citrus

Há aproximadamente 15 anos, a citricultura brasileira vem sofrendo consideráveis perdas em produtividade e qualidade dos frutos devido ao ataque do fitopatógeno Alternaria alternata f.sp. citri, causador da Mancha Marrom da Alternaria (MMA), o controle da doença ainda é feito com o uso massivo de agroquímicos, chegando a vinte aplicações por período reprodutivo. O presente trabalho avaliou a eficiência no controle do MMA Triaca, T.; Cavião, H,C.; Pansera, M.R.; Venturin, L.; Sartori, V.C. Determinação de atividade antifúngica de extratos vegetais em Alternaria citrus. Summa Phytopathologica, v.44, n.2, p.185-188, 2018.