2 documentos corresponden a la consulta.
Palabras contadas: paraguariensis: 7, ilex: 20
Gottlieb, A.M. - Giberti, G.C. - Poggio, L.
Am. J. Bot. 2005;92(2):352-369
2005
Temas: AFLP - Direct optimization - Ilex - ITS - Sensitivity analysis - molecular analysis - sensitivity analysis - taxonomy - Aquifoliaceae - Embryophyta
Descripción: In order to clarify the relationships among southern South American (sSA) representatives of the genus Ilex, an amplified fragment length polymorphism (AFLP) analysis was accomplished. In addition, the phylogenetic relationships of the species were studied using ribosomal internal transcribed spacer (ITS) sequence data alone and in combination with AFLP data, taking into account the possible existence of paralogous sequences and the influence of alignment parameters. To explore stability of phylogenetic hypotheses, a sensitivity analysis was performed using 15 indel-substitution models. Within each species assayed, the AFLPs allowed the recognition of several diagnostic bands. Furthermore, the AFLP analysis revealed that individuals belonging to the same morpho-species formed coherent clades. In addition, some cases of geographical association were noted. Studies on ITS sequences revealed divergence between data obtained herein and sequence data downloaded from GenBank. The sensitivity analyses yielded different interspecific hypotheses of relationships. Notwithstanding, analyses of the ITS data alone and in combination with AFLPs, rendered clades stable to variation in the analytical parameters. Topologies obtained for the AFLPs, the ITS data alone and the combined analyses, demonstrated the existence of a group formed by I. argentina, I. brasiliensis, I. brevicuspis, I. integerrima, and I. theezans, and that I. dumosa and I. paraguariensis were distantly related to the former. Incongruence with traditional taxonomical treatments was found.
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Hartwig, V.G. - Brumovsky, L.A. - Fretes, R.M. - Boado, L.S.
Cienc. Tecnol. Aliment. 2012;32(1):126-133
2012
Temas: Antioxidant capacity - Dpph - Ilex paraguariensis - Yerba maté - Croton ovalifolius - Ilex paraguariensis
Descripción: Yerba maté extracts have in vitro antioxidant capacity attributed to the presence of polyphenolic compounds, mainly chlorogenic acids and dicaffeoylquinic acid derivatives. DPPH is one of the most used assays to measure the antioxidant capacity of pure compounds and plant extracts. It is difficult to compare the results between studies because this assay is applied in too many different conditions by the different research groups. Thus, in order to assess the antioxidant capacity of yerba maté extracts, the following procedure is proposed: 100 μL of an aqueous dilution of the extracts is mixed in duplicate with 3.0 mL of a DPPH 'work solution in absolute methanol (100 μM.L-1), with an incubation time of 120 minutes in darkness at 37 ± 1 °C, and then absorbance is read at 517 nm against absolute methanol. The results should be expressed as ascorbic acid equivalents or Trolox equivalents in mass percentage (g% dm, dry matter) in order to facilitate comparisons. The AOC of the ethanolic extracts ranged between 12.8 and 23.1 g TE % dm and from 9.1 to 16.4 g AAE % dm. The AOC determined by the DPPH assay proposed in the present study can be related to the total polyphenolic content determined by the Folin-Ciocalteu assay.
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