Sergio Augusto de Loreto Bordignon

Acaricidal properties of the essential oil from Hesperozygis ringens (Lamiaceae) on the cattle tick Riphicephalus (Boophilus) microplus.

Hesperozygis ringens (Benth.) Epling (Lamiaceae) is a strongly aromatic plant employed popularly for its antiparasitic properties. The leaves afforded 4% of essential oil constituted mainly by pulegone (86%). Laboratory tests were carried out to determine the toxicity of the essential oil species on engorged females and larvae of the cattle tick Riphicephalus (Boophilus) microplus using the adult immersion test (AIT) and the larval immersion test (LIT). It was observed that the essential oil at the concentration of 50 microL/mL and 25 microL/mL inhibited the egg laying significatively in relation to the controls and the eggs from these treated females were affected by the oil; the hatching was inhibited in 95% and 30%, respectively. In the LIT it was verified that the LC(99.9), LC(50) and LC(1) was 0.541 microL/mL, 0.260 microL/mL and 0.015 microL/mL, respectively. Pulegone, isolated from the oil, showed similar effect on the females and on the larvae, indicating that it is responsible for the oil activity.

Screening for the Presence of Hypericins in Southern Brazilian Species of Hypericum

Eight species of Hypericum (H. brasiliense, H. caprifoliatum, H. carinatum, H. connatum, H. cordatum, H. myrianthum, H. piriai and H. polyanthemum) growing in southern Brazil were analyzed by TLC and HPLC for the presence of hypericin and pseudohypericin. Although these polycyclic quinones have been identified in some Hypericum species, they were not detectable in the presently assessed samples. The chemotaxonomy of the taxon is briefly discussed.

Chemical composition and toxicity of the essential oils from Cunila species (Lamiaceae) on the cattle tick Rhipicephalus (Boophilus) microplus.

The essential oils obtained from the aerial parts of five species of Cunila (Lamiaceae) native to Southern Brazil were analyzed by GC and GC/MS. The oil of Cunila angustifolia was characterized by sabinene; Cunila incana is rich in α-pinene and β-pinene, Cunila spicata and Cunila microcephala presented menthofuran as the main component, and in the essential oil of Cunila incisa, the major component was 1,8-cineole. Laboratory tests were carried out to determine the effect of the essential oils of the above cited plants on larvae of the cattle tick Riphicephalus (Boophilus) microplus. C. angustifolia, C. incana, and C. spicata were the most active samples killing almost the totality of the larvae. C. incisa and C. microcephala showed low acaricidal effect.

Composição química e atividade antioxidante do óleo volátil de eupatorium polystachyum dc.

The essential oil obtained from leaves and flowers of Eupatorium polystachyum DC. (Asteraceae) collected in Rio Grande do Sul State, Brazil, was characterized by GC-MS and its antioxidant activity was assessed by DPPH assay. The yield of essential oil, relative to fresh material, was 1.6 and 0.9% for leaves and flowers, respectively. Both oils are constituted exclusively by terpenic compounds. Leaf oil contains great quantity of monoterpenes (66.4%); on the other hand, inflorescence oil contains comparable quantities of mono- and sesquiterpenes (51.8 and 47.7%, respectively). The same compounds are majority in both oils: b-pinene (14.7 and 9.8%), b-myrcene (15.3 and 10.8%) and limonene (22.8 and 20.5%) among monoterpenes and b-caryophyllene (10.4 and 15.4%), germacrene D (7.2 and 9.4%) and bicyclogermacrene (12.0 and 19.2%) among sesquiterpenes. The oils had antioxidant activity by DPPH assay in 1:10 dilution in ethyl ether (v/v).

In vitro Cytotoxicity of Extracts from Brazilian Asteraceae

Aqueous and organic extracts of Asteraceae (Compositae) collected from the State of Rio Grande do Sul, Brazil, have been tested in vitro for cytotoxic activity against human solid tumour cell lines. Twenty-five species, 125 extracts in total, were screened against HT29 human colon adenocarcinoma cells and NCI-H460 human non-small cell lung cancer cells. Twenty-five extracts from 11 species demonstrated cytotoxicity at 100µg/ml against one or both of the cell lines tested. Further analysis was performed on the active extracts using three cell lines HT29, NCI-H460, and U373 human glioblastoma cells, to determine the IC 50 and the degree of tumour cell line selectivity. Extracts from Baccharis coridifolia, Baccharis ochracea, Eupatorium macrocephalum, Eupatorium pedunculosum and Stenachaenium riedelii all produced IC 50 values below 5µg/ml. Comparison of the IC 50 results between cell lines identified that Baccharis coridifolia, Baccharis ochracea, Eupatorium laevigatum and Pluchea sagittalis extracts produced differential sensitivity across the panel of three cell lines. These species are currently under further investigation with the ultimate objective of isolation and identification of the active principles responsible for the anti-proliferative activity.

Essential oils of Cunila galioides and Origanum majorana as anesthetics for Rhamdia quelen: efficacy and effects on ventilation and ionoregulation

No presente estudo foi avaliada a eficacia da anestesia e possiveis efeitos dos oleos essenciais (EOs) de Cunila galioides (EOC) e Origanum majorana (EOO) sobre a taxa ventilatoria (VR) e regulacao ionica em Rhamdia quelen. Nas avaliacoes de anestesia, as concentracoes de 50, 100, 200 e 300 μL L-1 EOC e 50, 100, 200, 300, 400 e 500 μL L-1 EOO foram testadas, e os tempos para a inducao as fases de sedacao e de anestesia, assim como recuperacao, foram mensurados. Um segundo ensaio empregou concentracoes mais baixas de ambos EOs: 10, 25, 50 e 100 μL L-1 a fim de verificar a VR e o fluxo liquido corporal dos ions Na+, K+ and Cl- . A sedacao foi alcancada para ambos os oleos em 100 μL L-1, e a anestesia em concentracoes ≥ 200 µL L-1. Nao houve diferenca significativa entre o controle e grupos tratados com EOs em relacao a VR, mas todos os peixes submetidos a 100 µL L-1 do EOC morreram dentro de 2 h de exposicao. No geral, a perda ionica declinou na presenca dos EOs. O EOC em 200 - 300 μL L-1 e o EOO em 400 - 500 μL L-1 apresentam potencial para anestesia rapida em R. quelen.

Chemical analysis and in vitro antiviral and antifungal activities of essential oils from Glechon spathulata and Glechon marifolia

Abstract Context: Glechon spathulata Benth. and Glechon marifolia Benth. (Lamiaceae, Mentheae) are aromatic plants used in traditional medicine for the treatment of viral infections. Objective: The chemical composition and antiviral and antifungal activities of Glechon spathulata and Glechon marifolia essential oils were investigated. Materials and methods: The oils were obtained by hydrodistillation and analyzed by GC–FID and GC–MS. Anti-herpes virus (HSV-1) activity was examined in Vero cells by yield reduction assay, in doses of 0.0095% v/v and 0.039% v/v, for G. spathulata and G. marifolia oil, respectively. Antifungal activity was carried by the broth microdilution method, in oil concentrations that ranged from 5.2 to 500 µg/mL. Results: β-Caryophyllene (14.2% and 32.2% for G. spathulata and G. marifolia, respectively) and bicyclogermacrene (17.1% and 16.5%, respectively) were the major components of both oils. At noncytotoxic concentrations of the essential oils, the viral titer was reduced by up to 2 log10 for KOS and VR-733 strains. The antifungal activity was observed against Trichophyton rubrum (MIC 10–83 µg/mL) and Epidermophyton floccosum (MIC 83–500 µg/mL). The oil of G. spathulata exhibited activity against the three strains tested (KOS, VR733, and 29-R), whereas G. marifolia oil was active against two strains, KOS and VR733. Discussion and conclusion: The chemical composition for G. spathulata and G. marifolia essential oils is very similar. The oil of G. spathulata can be promising as a new antifungal agent against dermatophytes. The findings add important information to the biological activity of Glechon species essential oils, specifically its antiviral and antidermatophytic properties.

Dimeric acylphloroglucinols from Hypericum austrobrasiliense exhibiting antinociceptive activity in mice.

Three dimeric acylphloroglucinols, austrobrasilol A, austrobrasilol B and isoaustrobrasilol B were isolated from the flowers of Hypericum austrobrasiliense (Hypericaceae, section Trigynobrathys). Their structures were elucidated using mass spectrometry and NMR experiments (1D and 2D), and by comparison with previously reported data for other dimeric acylphloroglucinols isolated from Hypericum and Elaphoglossum genera. The three compounds were orally administered in mice at equimolar doses to uliginosin B (15mg/kg, p.o.) displaying antinociceptive activity in the hot-plate test. The compounds did not induce motor impairment in the rotarod apparatus.

Characterization of Phloroglucinol-enriched Fractions of Brazilian Hypericum Species and Evaluation of Their Effect on Human Keratinocytes Proliferation.

In this study, a phytochemical and biological investigation on five South Brazilian Hypericum species (Hypericum caprifoliatum, Hypericum carinatum, Hypericum connatum, Hypericum myrianthum, and Hypericum polyanthemum) was carried out. The phloroglucinol‐enriched fractions (PEF) of the flowering aerial parts were analyzed by high‐performance liquid chromatography for the content of uliginosin A (1), japonicin A (2), uliginosin B (3), hyperbrasilol B (4), and the three benzopyrans, that is, 6‐isobutyryl‐5,7‐dimethoxy‐2,2‐dimethyl‐benzopyran (HP1) (5), 7‐hydroxy‐6‐isobutyryl‐5‐methoxy‐2,2‐dimethyl‐benzopyran (HP2) (6), and 5‐hydroxy‐6‐isobutyryl‐7‐methoxy‐2,2‐dimethyl‐benzopyran (HP3) (7). After chemical characterization, the PEF were assayed for cell proliferation on human keratinocyte cell line by MTT. The H. carinatum and H. polyanthemum PEF demonstrated better results with an increase in cell proliferation (138.7% and 120.6%, respectively). The cell counting and Ki‐67 assay with H. carinatum PEF confirmed the MTT results. The cell cycle distribution indicates an increase in the cells at S and G2/M phases, which is indicative of proliferation induction. In summary, the results indicate an induction of HaCaT proliferation by the treatment with H. carinatum PEF (at 10 and 15 µg/mL), suggesting a possible use as wound healing agent. Copyright

The monoamine oxidase inhibitory activity of essential oils obtained from Eryngium species and their chemical composition

Abstract Context Monoamine oxidase (MAO) inhibitors are used in the treatment of depression, anxiety disorders, and the symptomatic treatment of Parkinsons disease. Eryngium, the most representative of the Apiaceae family, is well known for the presence of essential oils (EOs), which have already demonstrated MAO inhibitory potential. Objective The objective of this study is to evaluate the MAO inhibitory capacity of the EOs obtained from Eryngium floribundum Cham. & Schlecht. (EF), E. eriophorum Cham. & Schlecht. (EE), E. nudicaule Lam. (EN), E. horridum Malme (EH), and E. pandanifolium Cham. & Schlecht. (EP). Materials and methods EOs were obtained from fresh whole plants by hydrodistillation (3 h). Chemical analyses were performed by GC/MS using apolar and polar columns, with oven temperature from 60 to 300 °C at 3 °C/min. The MAO-A and -B activities were evaluated in vitro by an end-point method using kynuramine as the substrate and mitochondrial suspension or human recombinant enzymes as the enzymatic source. DMSO 2%, clorgyline 10−7 M, and pargyline 10−6 M were used as controls. Results and discussion EFEO, EEEO, ENEO, EHEO, and EPEO GC/MS analysis showed (E)-caryophyllene (4.9–10.8%), germacrene D (0.6–35.1%), bicyclogermacrene (10.4–17.2), spathulenol (0.4–36.0%), and globulol (1.4–18.6%) as main constituents. None of the EOs inhibited MAO-A activity (4 and 40 μg/mL). However, EHEO inhibited MAO-B activity with an IC50 value of 5.65 μg/mL (1–200 μg/mL). Pentadecane (10 μM), its major constituent (53.5%), did not display significant MAO-B inhibition. Conclusion The study demonstrates the promising application of Eryngium species as a source of potential central nervous system bioactive secondary metabolites, specially related to neurodegenerative disorders.