Denudatin A, a Dimeric Acylphloroglucinol from Hypericum denudatum Presents an Antinociceptive Effect in Mice.

A new dimeric acylphloroglucinol, denudatin A (1), was isolated from the flowering aerials parts of Hypericum denudatum, along with the known phloroglucinols selancin A (2), hyperbrasilol A (3), uliginosin B (4), and isouliginosin B (5). The structure of 1 was elucidated using 1D, 2D NMR, and MS experiments, and by comparison with previously reported data for Hypericum dimeric acylphloroglucinols. Denudatin A (1) and selancin A (2) were administered orally to mice displaying antinociceptive activity in the hot plate test. The compounds did not induce motor impairment in the rotarod apparatus.

Antimicrobial activity of dimeric acylphloroglucinols isolated from southern Brazilian Hypericum species against to resistant bacterial.

The hexanic extracts of Hypericum austrobrasiliense, H. caprifoliatum, H. denudatum, H. pedersenii and H. polyanthemum, and three isolated dimeric acylphloroglucinols (uliginosin B, japonicine A and hyperbrasilol B) were assayed for their antimicrobial activity against some Gram-positive and Gram-negative bacteria (including resistant strains). These extracts were assayed using the disc diffusion test, and the results indicated that the tested species did non exhibit activity on the Gram-negative strains. Subsequently, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were measured using the broth dilution technique adopted to macrodillution. The most susceptible strains were the MRSA and the S. aureus MLSb. Regarding these pathogens, the better MIC values were obtained with the extracts from H. austrobrasiliense, H. caprifoliatum and H. pedersenii. The acylphloroglucinols uliginosin B and hyperbrasilol B presented the lowest MIC values against Enterococcus faecalis, Staphylococcus aureus, MRSA and S. aureus MLSb resistance.

Two morphotypes versus two chemotypes of Psidium cattleyanum: Chemical and pharmacological comparison and a rational approach for marker selection.

Psidium cattleyanum has two morphotypes: one with yellow fruits and other with red fruits. The leaves are popularly used as anti-inflammatory. However, no distinction is made between the types. Therefore, this study compared chemical and pharmacological data of both morphotypes to select proper biomarkers to ensure P. cattleyanum leaves quality. After extraction optimization by experimental design, 28 samples were analyzed by HPLC. Using Principal Component Analysis, it was possible to detect two chemotypes, unrelated to the color of the fruits. However, the extracts obtained from both chemotypes seemed to play similar anti-inflammatory effect, demonstrated by anti-chemotactic activity. The compounds common to both chemotypes were isolated and identified as hyperoside, miquelianin and quercitrin; these compounds also demonstrated anti-inflammatory potential. Since both chemotypes played similar activity, along with the isolated flavonoids, these flavonoids were selected as biomarkers for quality control of P. cattleyanum leaves. Following ICH guidelines, a HPLC method was validated. In summary, this study demonstrated that hyperoside, miquelianin and quercitrin can be used as biomarkers for quality control of P. cattleyanum leaves and a method was developed and validated to be used interchangeably for both morpho- and chemotypes.

Monoamine Oxidase Inhibitory Activity of Biflavonoids from Branches of Garcinia gardneriana (Clusiaceae).

Garcinia gardneriana is chemically characterized by the presence of biflavonoids. Taking into account that flavonoids are able to inhibit monoamine oxidase (MAO) activity, in the present study, the chemical composition of the branches' extract of the plant is described for the first time and the MAO inhibitory . activity of the isolated biflavonoids was evaluated. Based on spectroscopic and spectrometric data, it was possible to identify volkesiflavone, morelloflavone (1), Gb-2a (2) and Gb-2a-7-Ο-glucoside (3) in the ethyl acetate fraction from ethanol extract of the branches. Compounds 1-3 were evaluated in vitro and demonstrated the capacity to inhibit MAO-A activity with an IC50 ranging from 5.05 to 10.7 µM, and from 20.7 to 66.2 µM for MAO-B. These inhibitions corroborate with previous IC50 obtained for monomeric flavonoids, with a higher selectivity for MAO-A isoform. The obtained results indicate that biflavonoids might be promising structures for the identification of new MAO inhibitory compounds.

Biological activities of essential oils from six genotypes of four Ocotea species

Abstract Essential oils from four Ocotea species collected in southern Brazil were evaluated for chemical composition using gas chromatography coupled with mass spectrometry. The primary compound identified in O. acutifolia essential oil was an unsaturated tetracyclic diterpene, phyllocladene (67.7%), followed by a sesquiterpene hydrocarbon, ß-selinene (18.0%). The sesquiterpene fraction was predominant in oils from two collections of O. puberula; ß-caryophyllene (25.2%) and globulol (22.6%) were the major compounds identified in collections 1 and 2, respectively. O. silvestris essential oil contained predominantly germacrene D and bicyclogermacrene. These compounds were also predominant in essential oil from O. indecora leaves collected from shady habitats. By contrast, essential oil extracted from O. indecora grown under direct sunlight contained mainly oxygenated sesquiterpenes, such as guaiol (30.2%), α-eudesmol (27.6%), and ß-eudesmol (12.7%). Chemotaxis assays showed that Ocotea essential oils had no significant inhibitory activity on leukocyte migration compared with a chemotactic stimulant (lipopolysaccharide from Escherichia coli). However, the oils exhibited antifungal activity against Candida parapsilosis, with a minimum inhibitory concentration of 500 µg/mL. To our knowledge, this is the first study to investigate the in vitro antifungal and antichemotactic activities of essential oils from Ocotea species native to southern Brazil

Endozoochory by Didelphis albiventris Lund, 1840 (Mammalia, Didelphimorphia) in a Semideciduous Seasonal Forest remnant in the South of Brazil / Endozoocoria por Didelphis albiventris Lund, 1840 (Mammalia, Didelphimorphia) em remanescente de Floresta Estacional Semidecidual no sul do Brasil

Abstract Seed dispersal is a process that is fundamental to maintenance of forest ecosystems, enabling plants to successfully germinate in sites that are favorable to their growth, minimizing risks of competition, the action of pathogens and predation by herbivores. Intraspecific and seasonal variations in fruit consumption by Didelphis albiventris, and its contribution to dispersal and germination of endozoochorous seeds were analyzed in a Semideciduous seasonal forest. The study was conducted at Morro do Coco, which is a hilly area in the municipal district of Viamão, RS, Brazil, bordering the shore of Guaíba lake (30º16'15"S, 51º02'54"W), between June 2013 and May 2014, with a total sampling effort of 2992 trap-nights. A total of 18 individuals were captured and 24 fecal samples were collected. Fruits were identified in 96% of the samples, corresponding to 18 plant species, belonging to 10 families. The most common species were Ficus cestrifolia and Syagrus romanzoffiana, which occurred in 66% of the samples, followed by Banara parviflora and Cecropia pachystachya, both with a 25% rate of occurrence. There were no differences between the richness of fruit consumed by males and females (t = 0.083; DF = 32; p = 0.934) and there were no seasonal variations (H = 3.165; p = 0.367). The greatest breadth of dietary niche occurred during the summer, when twice as many fruit species were recorded in the diet than during the autumn, which was the season with the smallest breadth. Both germination percentage and germination velocity of Ficus cestrifolia and Psidium sp. seeds increased after passage through the animals' digestive tracts (percentage germination increased more than 40% and velocity was up to 7 times highest). Didelphis albiventris can be considered a frugivorous-omnivorous species, since fruit are an important item of its diet, and it contributes to dispersal of a large quantity of small endozoochorous seeds, increasing both germination percentage and germination velocity of some species.

Resumo A dispersão de sementes é um processo fundamental à manutenção de ecossistemas florestais, favorecendo o sucesso germinativo de plantas em locais adequados ao seu crescimento, minimizando a competição, a ação de patógenos e a predação por herbívoros. Variações intra-específicas e sazonais no consumo de frutos por Didelphis albiventris, bem como sua contribuição à dispersão e germinação de sementes endozoocóricas foram avaliados em Floresta Estacional Semidecidual. O estudo foi realizado no Morro do Coco, localizado no município de Viamão, RS às margens do Lago Guaíba (30º16'15"S, 51º02'54"W), entre junho de 2013 a maio de 2014, resultando em um esforço amostral de 2992 armadilhas-noite. Foram capturados 18 indivíduos e coletadas 24 amostras fecais. Frutos estiveram presentes em 96% das amostras e corresponderam a 18 espécies vegetais, pertencentes a 10 famílias. As espécies mais frequentes foram Ficus cestrifolia e Syagrus romanzoffiana, que ocorreram em 66% das amostras, seguidas de Banara parviflora e Cecropia pachystachya, ambas com 25% de ocorrência. Machos e fêmeas não diferiram quanto à riqueza de frutos consumidos (t = 0.083; DF = 32; p = 0.934), o que também não variou sazonalmente (H = 3.165; p = 0.367). A maior amplitude de nicho trófico ocorreu no verão, registrando-se duas vezes mais frutos na dieta do que no outono, estação com a menor amplitude. Tanto a porcentagem quanto a velocidade de germinação das sementes de Ficus cestrifolia e Psidium sp. aumentaram após a passagem pelo trato digestório do animal (a porcentagem de germinação aumentou mais de 40% e a velocidade foi até 7 vezes maior). Didelphis albiventris pode ser considerada uma espécie frugívora-onívora, uma vez que frutos representam um item importante na dieta, e contribui para a dispersão de grande quantidade de sementes endozoocóricas pequenas, aumentando tanto o percentual quanto a velocidade de germinação de algumas espécies.

Germination and growth inhibitory effects of Hypericum myrianthum and H. polyanthemum extracts on Lactuca sativa L.

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.