ABSTRACT
Abstract Previous pre-clinical studies demonstrated that a valepotriates enriched fraction from Valeriana glechomifolia F.G. Mey., Caprifoliaceae, was effective against lipopolysaccharide from Escherichia coli (LPS)-induced sickness behavior as well as significantly decreased the cortical expression of pro inflammatory cytokines interleukin-1β and tumor necrosis factor-α. Other studies revealed anti-inflammatory properties of V. wallichii and V. amurensis. These findings open up new perspectives for Valeriana genus pharmacology, once it has been commonly associated to sedative and anxiolytic properties. The aim of this study was to investigate the antichemotactic, antinociptive and anti-inflammatory activities of a valepotriate-enriched fraction obtained from aerial and subterranean parts of V. glechomifolia submitted to supercritical CO2 extraction. The biological activities were assessed by means of formalin test in CF1 mice and Wistar rat's leukocytes migration assay (modified Boyden chamber method). Valepotriate-enriched fraction (1, 10 and 30 mg/kg, p.o.) inhibited the nociceptive behavior in the late phase of the formalin test in a dose dependent manner. The effect of the valepotriate-enriched fraction highest dose was comparable with that of diclofenac 50 mg/kg (p.o.). Valepotriate-enriched fraction (0.1-1 µg/ml) inhibited the leukocyte migration induced by lipopolysaccharide from Escherichia coli in a concentration dependent manner. This antichemotatic effect was comparable with that of indomethacin (0.1-1 µg/ml) and better than diclofenac (1 µg/ml) effect. This study demonstrated for the first time that a valepotriate-enriched fraction obtained from V. glechomifolia display a peripheral anti-inflammatory like activity.
ABSTRACT
AbstractDepending on the method of extraction, plant extracts can contain an enormous variety of active molecules, such as phenolic compounds, essential oils, alkaloids, among others. In many cases, from a pharmacological point of view, it is interesting to work with crude extract or fractions instead of a single isolated compound. This could be due to multi-targeting effect of the extract, lack of knowledge of the active compounds, synergistic effect of the extract compounds, among others. In any case, in order to achieve a final product some issues must be overcome, including poor stability, solvent toxicity, and low solubility of the bioactive compound. Recently many nanotechnology-based strategies have been proposed as an alternative to solve these problems, especially liposomes, nanoemulsions and nanoparticles. In this sense, the present work aims to review the main nanotechnological approaches used for association of different plant extracts and the main achievements from using these technologies.
ABSTRACT
Germination and growth inhibitory effects of ethanolic crude extracts of Hypericum myrianthum and H. polyanthemum aerial parts on lettuce (Lactuca sativa) were investigated. The germination was retarded in all the tested concentrations. After seven days the final germination percentage of the most concentrated extracts was significantly reduced by both extracts in comparison with the control. The radicles length was significantly affected showing necrosis. Both species present phenolic compounds as the main components and they could be responsible for the inhibition of the germination and growth of Lactuca sativa.
Neste trabalho foi investigado o efeito inibitório de extratos etanólicos de partes aéreas de Hypericum myrianthum e Hypericum polyanthemum sobre a germinação e o crescimento de alface (Lactuca sativa). A germinação das sementes foi reduzida em todas as concentrações avaliadas. Após sete dias, o percentual de germinação foi significativamente retardado pelos extratos de ambas as plantas, nas maiores concentrações, em comparação com o grupo controle. O comprimento das radículas foi significativamente afetado, estas apresentando alguns sinais de necrose. As duas espécies apresentam compostos fenólicos como constituintes principais, os quais podem ser responsáveis pela inibição da germinação e crescimento de Lactuca sativa.