Lignoids in seedlings of Virola sebifera

Quantitative analysis carried out by high performance liquid chromatography indicated the accumulation of a major secondary compound in seedlings of Virola sebifera which was isolated and identified as the lignan hydroxy-otobain. This lignan occurs only in trace amounts in the seeds, where cyclolignans (aryltetralones) are by far the major components. In addition to hydroxy-otobain, only hydroxy-aryltetralones were detected in the seedlings, indicating a selective process in the translocation of secondary compounds. Copyright (C) 2000 John Wiley & Sons, Ltd.

Butanolides as a common feature of Iryanthera lancifolia and Virola surinamensis

A comparative phytochemical study between pericarps of Iryanthera lancifolia and Virola surinamensis showed that the first one contains a new pair of epimeric 2-alkenyl-gamma-lactones, besides an aryltetralinic lignan and one tocotrienol, while the second species contains the lignans, galgravin and veraguensin, seven juruenolides: juruenolides C, D, F, G and epi-juruenolides D, F, G, together with three pairs of epimeric aliphatic 2-alkenyl-gamma-lactones. Juruenolide F, epi-juruenolides D, F, G and the 2-alkenyl-gamma-lactones are new natural compounds. (C) 1998 Elsevier B.V. Ltd. All rights reserved.

Configurational analysis of cubebins and bicubebin from Aristolochia lagesiana and Aristolochia pubescens

(8S,8'R,9S)-, (8R,8'R,9R)-, and (8R,8',R,9S)-cubebins, together with (8R,8'R,8R,8'''R,9R,9S)-bicubebin, were isolated from Aristolochia lagesiana and Aristolochia pubescens. Their structures were determined by spectroscopic methods, including H-1 and C-13 NMR spectroscopy at low temperatures, and by chemical transformations. (c) 2006 Elsevier Ltd. All rights reserved.

Microbial Transformations of Aryltetralone and Aryltetralin Lignans by Cunninghamella echinulata and Beauveria bassiana

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Lignoids; flavonoids and polyketides of Virola surinamensis

From the seeds of Virola surinamensis, which were collected near Altamira and near Maraba, Para State, Brazil, the following substances were isolated by chromatographic techniques: two dibenzylbutanediol lignans, dihydrocubebin and the new dihydrocubebin monolaurate, two furofuran lignans, sesamin and asarinin, three dibenzylbutyrolactol lignans, cubebin, β-O- methylcubebin and α-O-methylcubebin, one dibenzylbutyrolactone lignan, hinokinin, one aryltetralin neolignan, galbulin, two tetrahydrofuran neolignans, galgravin and the new 4'-hydroxy-3'-methoxy-3,4-methylenedioxy- 8.8',7.O.7'-neolignan, one flavone, tithonine, one isoflavone, irisolidone, and two new polyketides, 3-hydroxy-1-(15-phenylpentadecanoyl)-2,6- cyclohexanedione and 1-(5-phenylpentanoyl)-2,6-cyclohexanedione. Different chemical constitutions of the fruits from the two localities were observed.

nor-Lignans from the leaves of Styrax ferrugineus (Styracaceae) with antibacterial and antifungal activity

Chemical examination of the leaves of Styrax ferrugineus yielded 5-[3'-(β-D-glucopyranosyloxy)propyl]-7-methoxy-2-(3',4'-dime-thoxyphenyl) benzofuran, along with the known nor-lignans 5-(3'-hydroxypropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl) benzofuran, 5-(3'-hydroxypropyl)-7-methoxy-2-(3',4'-dimethoxyphenyl)benzofuran, 5-[3'-(β-D-glucopyranosyloxy)propyl]-7-methoxy-2-(3', 4'-methylenedioxyphenyl)benzofuran and the lignan, dihydrodehydrodiconiferyl alcohol. All arylpropanoids isolated showed antibacterial and antifungal activities. The structures of the isolates were established by spectroscopic analysis. (C) 2000 Elsevier Science Ltd.

Aryltetralone lignans and 7,8-seco-lignans from Holostylis reniformis

Aryltetralone lignans and two 7,8-seco-lignans were isolated from the acetone and hexane extracts of the roots of Holostylis reniformis, together with (-)-galbacin. Their structures were determined by spectroscopic methods. © 2004 Elsevier Ltd. All rights reserved.

Effects of (-)-cubebin (Piper cubeba) on cytotoxicity, mutagenicity and expression of p38 MAP kinase and GSTa2 in a hepatoma cell line

(-)-Cubebin is a lignan extracted from the seeds of the pepper Piper cubeba, a commonly eaten spice with beneficial properties, including trypanocidal, anti-inflammatory, analgesic, anti-proliferative and leishmanicidal activities. Because of its therapeutic potential, we investigated the effects of (-)-cubebin on the cytotoxicity, cell proliferation kinetics, mutagenicity and expression of p38 MAP kinase and glutathione S-transferase a2 (GSTa2) using real-time RT-PCR in Rattus norvegicus hepatoma cells. We found that 280 μM (-)-cubebin was cytotoxic after 24, 48 and 72. h of exposure, but not mutagenic at 0.28 μM, 2.8 μM and 28 μM after 26. h. Similarly, exposure to 0.28 μM, 2.8 μM and 28 μM (-)-cubebin for 24, 48, 72 and 96. h did not alter the cell proliferation kinetics. Cells exposed to 28 μM (-)-cubebin for 24. h did not exhibit changes in p38 MAP kinase and GSTa2 expression, indicating that cellular changes were not induced by extracellular stimuli and that (-)-cubebin is likely not metabolized via this pathway. Our results suggest that high levels of (-)-cubebin should be consumed with caution due to the cytotoxic effect observed at the highest concentration. However, at lower concentrations, no cytotoxic, mutagenic or proliferative effects were observed, providing further evidence of the safety of consuming (-)-cubebin. © 2013 Elsevier Inc.

Sesquiterpenos e lignanas de Holostylis reniformis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Terpenos e lignanas de Aristolochiaceae

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo químico e avaliação da atividade biológica de Eugenia brasiliensis e Eugenia involucrata (Myrtaceae)

Pós-graduação em Química - IQ

Biotransformação e sequestro de micromoléculas de Aristolochia giberti por Battus polydamas

Pós-graduação em Química - IQ

Microbial transformations of Aryltetralone and Aryltetralin Lignans by Cunninghamella echinulata and Beauveria bassiana

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)