Marcelo Rossato

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.

Extraction of essential oils from lime (Citrus latifolia Tanaka) by hydrodistillation and supercritical carbon dioxide

Neste trabalho o oleo essencial de lima acida foi extraido por hidrodestilacao e CO2 supercritico. No caso da hidrodestilacao, os parâmetros avaliados foram o tempo de processo e caracteristicas do material vegetal. Em extracao supercritica, os parâmetros avaliados foram temperatura, pressao e fluxo do CO2, tempo de processo e caracteristicas do material. Considerando o conteudo de citral, os melhores resultados para hidrodestilacao foram obtidos em um tempo de processo de 3 horas utilizando-se cascas inteiras. Os melhores resultados para extracao supercritica foram obtidos a 60oC, 90 bar, a um fluxo de CO2 de 1 mL/ min para 30 minutos de processo utilizando-se cascas moidas. Os melhores resultados em termos de rendimento de oleo essencial foram obtidos por hidrodestilacao (5,45% p/p) e extracao supercritica (7,93% p/p), para cascas moidas.

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.

Efeito fungicida dos óleos essenciais de Schinus molle L. e Schinus terebinthifolius Raddi, Anacardiaceae, do Rio Grande do Sul

Uma das alternativas para reduzir o uso de agrotoxicos pode ser a utilizacao de oleos essenciais para o controle de doencas e pragas que afetam a producao agricola. O objetivo do presente estudo foi verificar o efeito fungicida dos oleos essenciais de Schinus molle L. e Schinus terebinthifolius Raddi, especies nativas amplamente distribuidas na regiao. Os oleos foram extraidos por hidrodestilacao e analisados por cromatografia gasosa. Os fungos fitopatogenos Alternaria spp., Botrytis spp., Colletotrichum spp. e Fusarium spp., foram isolados a partir de gerberas e rosas com sintomas de doenca e os ensaios de atividade antifungica foram realizados atraves da tecnica de difusao em disco e os dados analisados pelo teste de Tukey e Duncan a 5%. Em geral o oleo essencial de S. molle foi efetivo para os quatro fungos testados, nas quatro diluicoes utilizadas e para todos os tempos avaliados e o oleo essencial de S. terebinthifolius apresenta efeito fungicida mais pronunciado contra Botrytis spp., a partir de testes in vitro.

Chemical Composition of the Essential Oils from Leaves and Fruits of Schinus molle L. and Schinus terebinthifolius Raddi from Southern Brazil

Abstract The essential oils of two Anacardiaceae species, Schinus molle L. and Schinus terebinthifolius Raddi, native from Brazil, were obtained by hydrodistillation and the oils composition studied by capillary GC and GC-MS. Twenty seven compounds were identified for S. molle and twenty nine for S. terebinthifolius. The leaves and fruits essential oils for both S. molle and S. terebinthifolius were characterised by a high percentage of sesquiterpene and monoterpene hydrocarbons. The S. terebinthifolius essential oils obtained from leaves and berries presented differences with those previously described in the literature, while the leave oil of S. molle showed similar composition to that from Uruguay. These findings have ecological and economic significance as S. molle and S. terebinthifolius are promising species in the pharmaceutical, cosmetic and chemical industries.

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.

Characterization of Nomuraea rileyi strains using polymorphic DNA, virulence and enzyme activity

The characterization of entomopathogenic microorganisms is important for the selection of more effective strains for use in integrated pest-control programs. Five Nomuraea rileyi strains (SA86101, GU87401, SR86151, CG128 and VA9101) were characterized using random amplified polymorphic DNA (RAPD) analysis, virulence studies and assessment of chitinolytic and proteolytic activity. RAPD analysis divided the strains into two groups with a similarity coefficient of 0,76%, group 1 consisting of strains SA86101, GU87401 and SR86151 and group 2 of strains CG128 and VA9101. The LT50 varied from 165h with strain VA9101 to 246h with strain GU87401. Chitinolytic and proteolytic activity of the fungi after 144h growth in minimal medium were tested using colloidal chitin as substrate. All strains exhibited enzyme activity, with strain VA9101 having the highest chitinase activity (0,0040 mmol/mL/min the 40oC) and strain SA86101 the highest proteolytic activity. No relationship was found between RAPD analysis, virulence and chitinase or protease activity.

Supercritical Extraction from Vinification Residues: Fatty Acids, α-Tocopherol, and Phenolic Compounds in the Oil Seeds from Different Varieties of Grape

Supercritical fluid extraction has been widely employed in the extraction of high purity substances. In this study, we used the technology to obtain oil from seeds from a variety of grapes, from vinification residues generated in the Southern region of the state of Rio Grande do Sul, Brazil. This work encompasses three varieties of Vitis vinifera (Moscato Giallo, Merlot, and Cabernet Sauvignon) and two of Vitis labrusca (Bordô e Isabel), harvested in 2005 and 2006. We obtained the highest oil content from Bordô (15.40%) in 2005 and from Merlot (14.66%), 2006. The biggest concentration of palmitic, stearic, and linoleic acids was observed in Bordô, 2005, and in Bordô, Merlot, and Moscato Giallo, 2006. Bordô showed the highest concentration of oleic acid and α-tocopherol in both seasons too. For the equivalent of procyanidins, we did not notice significant difference among the varieties from the 2005 harvest. In 2006, both varieties Isabel and Cabernet Sauvignon showed a value slightly lower than the other varieties. The concentration of total phenolics was higher in Bordô and Cabernet Sauvignon. The presence of these substances is related to several important pharmacological properties and might be an alternative to conventional processes to obtain these bioactives.