Fabiana Agostini

Phenolic content of grapevine leaves (Vitis labrusca var. Bordo) and its neuroprotective effect against peroxide damage.

In some countries, leaves of Vitis vinifera grapes have been used for food and for treating many medical disorders. However, there are no studies on the leaves of Vitis labrusca, the main species used for wine and juice production in South America. In this work, the phenolic compounds and antioxidant activity of organic and conventional grape leaves extracts prepared from V. labrusca (var. Bordo) in brain tissues (in vitro model) have been evaluated. Both organic and conventional grape leaves extracts have similar total phenolic content, however, different patterns were observed for the main phenolic compounds of both kinds of leaves. The organic leaves extract showed about 10 times more resveratrol than the conventional one. Both extracts were able to reduce the lipid and protein damages induced by hydrogen peroxide in the brain of rats. This effect was accompanied by the reversion of the hydrogen peroxide-induced alterations in the superoxide dismutase and catalase activities. Negative correlations between lipid and protein damages and the levels of polyphenols were found, suggesting that these compounds contribute directly to the protective effect observed.

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.

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.

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.

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.

Araucaria Angustifolia: A Potential Nutraceutical with Antioxidant and Antimutagenic Activities

The Araucaria angustifolia (Bertolini, Otto Kuntze) tree belongs to the family Araucariaceae and is known as Brazilian pine. The female strobilus consists of seeds (the edible part of A. angustifolia) and bracts (non-developed seeds). These bracts, which represent approximately 80% of the female strobilus, have no use. It has previously been suggested that the dietary intake of antioxidants could be a useful strategy to reduce the incidence of diseases associated with oxidative stress, such as cancer, atherosclerosis and neurodegenerative disorders. This study aimed to evaluate the phenolic profile and the possible antioxidant, mutagenic and antimutagenic activities of the aqueous extract from bracts of A. angustifolia. The results showed that the extract of A. angustifolia presents important in vitro and in vivo antioxidant activity. Additionally, lower concentrations of the extract were non-mutagenic and avoided DNA damage induced by hydrogen peroxide in yeast cells. Catechin, epicatechin and rutin were the main phenolic compounds found in the extract. These results may provide new perspectives for the development of strategies with natural compounds in the nutraceutical field. In addition, the use of this waste will help maintain the environmental balance.

Antioxidant and Antigenotoxic Activities of the Brazilian Pine Araucaria angustifolia (Bert.) O. Kuntze

Polyphenols are natural products with recognized potential in drug discovery and development. We aimed to evaluate the polyphenolic profile of Araucaria angustifolia bracts, and their ability to scavenge reactive species. The antioxidant and antigenotoxic effects of A. angustifolia polyphenols in MRC5 human lung fibroblast cells were also explored. The total polyphenol extract of A. angustifolia was determined by the Folin–Ciocalteu reagent and the chemical composition was confirmed by HPLC. Reactive oxygen species’ scavenging ability was investigated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and superoxide dismutase- and catalase-like activities. The protective effect of the extract in MRC5 cells was carried out by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method and the determination of oxidative lipids, protein, and DNA (alkaline and enzymatic comet assay) damage. Total phenolic content of the A. angustifolia extract was 1586 ± 14.53 mg gallic acid equivalents/100 g of bracts. Catechin, epicatechin, quercetin, and apigenin were the major polyphenols. The extract was able to scavenge DPPH radicals and exhibited potent superoxide dismutase and catalase-like activities. Moreover, A. angustifolia extract significantly protected MRC5 cells against H2O2-induced mortality and oxidative damage to lipids, proteins, and DNA. Therefore, A. angustifolia has potential as a source of bioactive chemical compounds.

Antioxidant Activity of Grapevine Leaf Extracts against Oxidative Stress Induced by Carbon Tetrachloride in Cerebral Cortex, Hippocampus and Cerebellum of Rats.

In recent years, it has become increasingly important to study the beneficial properties of derivatives of grapes and grapevine. The objective of this study was to determine the antioxidant activity of Vitis labrusca leaf extracts, comparing conventional and organic grapevines, in different brain areas of rats. We used male Wistar rats treated with grapevine leaf extracts for a period of 14 days, and on the 15th day, we administered in half of the rats, mineral oil and the other half, carbon tetrachloride (CCl4). The animals were euthanized by decapitation and the cerebral cortex, hippocampus and cerebellum were removed to assess oxidative stress parameters and the activity of antioxidant enzymes. Lipid peroxidation levels (TBARS) were unchanged. However, CCl4 induced oxidative damage to proteins in all tissues studied, and this injury was prevented by both extracts. Superoxide dismutase (SOD) activity was increased by CCl4 in the cerebral cortex and decreased in other tissues. However, CCl4 increased catalase (CAT) activity in the cerebellum and decreased it in the cerebral cortex. The SOD/CAT ratio was restored in the cerebellum by both extracts and only in the cerebral cortex by the organic extract.

Antioxidant Effect of Lippia alba (Miller) N. E. Brown

Lippia alba is a shrub found in all regions of Brazil and other countries in South and Central America. L. alba exhibits variability among its different accessions, showing differences in morphology and in the composition of its essential oil. This study evaluated the phenolic profiles and the antioxidant activities of seven different accessions of L. alba. The seven accessions of L. alba studied exhibited an important phenolic content, and all accessions demonstrated antioxidant activity with different efficacies. The main flavonoids in all accessions were apigenin, luteolin, naringin and rutin. The Santa Vitória do Palmar accession exhibited higher naringin and total phenolic content. This extract was able to reduce hydrogen peroxide-induced oxidative damage in tissue homogenates of cerebellum, cerebral cortex, hippocampus and liver of Wistar rats.