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1.
J Ethnopharmacol ; 103(1): 43-52, 2006 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-16169692

RESUMO

Rhodiola rosea is a medicinal plant having stimulating and adaptogenic properties, and some reports also indicate its anticancer and antimutagenic effect. However, the mechanism of its anticancer effect is unknown as there have been no cytological studies regarding cytostatics, cell cycle, induction of apoptosis or the mitotic activity of healthy and cancerous cells. In the present paper, those parameters were investigated using HL-60 cells, with flow cytometry and fluorescence microscopy. It has been found that the extract of Rhodiola rosea rhizomes inhibits division of HL-60 cells, which is preceded by an accumulation of cells at the prophase stage. This leads to induction of apoptosis and necrosis in HL-60 cells, and to marked reduction of their survival. The cells enter apoptosis from phase G2/M of the cell cycle. After treatment with the extract, no chromosome aberrations or micronuclei were observed, which indicates the mild action of the extract. The cytostatic and antiproliferative effect of the Rhodiola rosea rhizome extract, and its mild action, raises hope for its use in anticancer therapy by enhancing the effectiveness of cytostatics.


Assuntos
Antimitóticos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rhodiola , Fase S/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Células HL-60 , Humanos , Índice Mitótico , Necrose
2.
Lipids ; 38(9): 981-90, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14584606

RESUMO

Polyisoprenoid alcohols of the plant Coluria geoides were isolated and analyzed by HPLC with UV detection to determine the nature of the polyprenol and dolichol mixture in the organs studied. In roots, a family of dolichols (Dol-15 to Dol-23, with Dol-16 dominating, where Dol-n is dolichol composed of n isoprene units) was accompanied by traces of polyprenols of similar chain lengths, whereas in hairy roots grown in vitro, identical patterns with a slightly broader chain-length range were found. Conversely, in leaves and seeds polyprenols were the dominant form, and their pattern was shifted toward longer chains (maximal content of Pren-19, where Pren-n is polyprenol composed of n isoprene units). Interestingly, the pattern of dolichols in seeds and leaves (in which Dol-17 dominated) was similar to that found in roots. Structures of the dolichols and polyprenols isolated were confirmed by the application of a new HPLC/electrospray ionization-MS method, which also offers a much higher sensitivity in detection of these compounds compared to a UV detector. The highest sensitivity was obtained when the [M + Na]+ ions of polyprenols and dolichols were recorded in the selected ion monitoring mode and a small amount of sodium acetate solution was added post-column to enhance the formation of these ions in an electrospray ion source.


Assuntos
Álcoois/química , Plantas/química , Terpenos/química , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Terpenos/isolamento & purificação
4.
J Plant Physiol ; 166(17): 1950-4, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19573947

RESUMO

This study assessed the effect of two precursors (l-phenylalanine and p-amino benzoic acid) used alone or in combination with methyl jasmonate, on the growth and accumulation of paclitaxel, baccatin III and 10-deacetylbaccatin III in hairy root cultures of Taxus x media var. Hicksii. The greatest increase in dry biomass was observed after 4 weeks of culturing hairy roots in medium supplemented with 1microM of l-phenylalanine (6.2gL(-1)). Addition of 1microM of l-phenylalanine to the medium also resulted in the greatest 10-deacetylbaccatin III accumulation (422.7microg L(-1)), which was not detected in the untreated control culture. Supplementation with 100microM of l-phenylalanine together with 100microM of methyl jasmonate resulted in the enhancement of paclitaxel production from 40.3microg L(-1) (control untreated culture) to 568.2microg L(-1), the highest paclitaxel content detected in the study. The effect of p-amino benzoic acid on taxane production was less pronounced, and the highest yield of paclitaxel (221.8microg L(-1)) was observed when the medium was supplemented with 100microM of the precursor in combination with methyl jasmonate. Baccatin III was not detected under the conditions used in this experiment and the investigated taxanes were not excreted into the medium.


Assuntos
Antineoplásicos Fitogênicos/biossíntese , Taxoides/metabolismo , Taxus/metabolismo , Acetatos/farmacologia , Alcaloides/biossíntese , Benzoatos/farmacologia , Biomassa , Meios de Cultura , Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Fenilalanina/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Taxus/efeitos dos fármacos , Taxus/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos
5.
Planta ; 224(3): 533-44, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16525783

RESUMO

Ergoline alkaloids (syn. ergot alkaloids) are constituents of clavicipitaceous fungi (Ascomycota) and of one particular dicotyledonous plant family, the Convolvulaceae. While the biology of fungal ergoline alkaloids is rather well understood, the evolutionary and biosynthetic origin of ergoline alkaloids within the family Convolvulaceae is unknown. To investigate the possible origin of ergoline alkaloids from a plant-associated fungus, 12 endophytic fungi and one epibiotic fungus were isolated from an ergoline alkaloid-containing Convolvulaceae plant, Ipomoea asarifolia Roem. & Schult. Phylogenetic trees constructed from 18S rDNA genes as well as internal transcribed spacer (ITS) revealed that the epibiotic fungus belongs to the family Clavicipitaceae (Ascomycota) whereas none of the endophytic fungi does. In vitro and in vivo cultivation on intact plants gave no evidence that the endophytic fungi are responsible for the accumulation of ergoline alkaloids in I. asarifolia whereas the epibiotic clavicipitaceous fungus very likely is equipped with the genetic material to synthesize these compounds. This fungus resisted in vitro and in vivo cultivation and is seed transmitted. Several observations strongly indicate that this plant-associated fungus and its hitherto unidentified relatives occurring on different Convolvulaceae plants are responsible for the isolated occurrence of ergoline alkaloids in Convolvulaceae. This is the first report of an ergot alkaloid producing clavicipitaceous fungus associated with a dicotyledonous plant.


Assuntos
Ascomicetos/metabolismo , Alcaloides de Claviceps/biossíntese , Ipomoea/microbiologia , Sementes/microbiologia , Ascomicetos/classificação , Ascomicetos/genética , Cromatografia Líquida de Alta Pressão , DNA Intergênico/análise , DNA Ribossômico/análise , Alcaloides de Claviceps/química , Genes Fúngicos , Ipomoea/embriologia , Ipomoea/metabolismo , Filogenia , Folhas de Planta/microbiologia , Folhas de Planta/ultraestrutura , Prenilação de Proteína , Triptofano/metabolismo
6.
Biotechnol Lett ; 27(17): 1301-4, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16215829

RESUMO

Paclitaxel and 10-deacetylbaccatin III (10-DAB III) were produced in suspension cultures of Taxus x media var. Hicksii grown in shake-flasks and in a 7-l bioreactor reaching, in the bioreactor, 4.4 mg l(-1) (on day 14) and 37.5 mg l(-1) (on day 11). In shake-flasks the highest total content of paclitaxel and 10-DAB III was 7.3 mg l(-1) (on day 4) and 8.8 mg l(-1) (on day 18). Phenylalanine, at 0.05 mM, increased paclitaxel accumulation in cells cultivated in bioreactor and flasks 30-fold and 9-fold (from 0.02 mg l(-1) to 0.6 mg l(-1) and to 0.2 mg l(-1), respectively). The 10-DAB III content in cells from flasks was increased from 0.4 mg l(-1) to 1.6 mg l(-1).


Assuntos
Reatores Biológicos , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Taxoides/metabolismo , Taxus/metabolismo , Paclitaxel/biossíntese
7.
J Appl Toxicol ; 23(3): 187-90, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12794940

RESUMO

In this study we assess the effect of pyrrolizidine alkaloids (PAs) extracted from Lithospermum canescens on the biology of the two-spotted spider mite (Tetranychus urticae Koch). Lithospermum canenscens (Michaux) Lehm. (Boraginaceae) is a common prairie plant also known as Indian paint or hoary puccoon. A mixture of seven PAs with known chemical structures was used in this investigation. Mites treated with PAs showed a high mortality of juveniles, a decrease in female fecundity and a shortened longevity. The intrinsic rate of population increase (r(m)) was used as an indicator of T. urticae population performance after treatment with PAs. The r(m) value obtained with alkaloid-treated leaves was lower than that for mites developing on untreated leaves, which indicates that the mite population would develop much slower on treated plants. The results suggest that further studies should be performed to assess the possible use of PA extracts for spider mite control.


Assuntos
Lithospermum , Alcaloides de Pirrolizidina/farmacologia , Tetranychidae/efeitos dos fármacos , Controle de Ácaros e Carrapatos , Animais , Feminino , Fertilidade/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Extratos Vegetais/farmacologia
8.
Chem Pharm Bull (Tokyo) ; 52(10): 1262-4, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15467251

RESUMO

We established callus cultures of the monocotyledonous plants Kniphofia foliosa and K. tuckii (Asphodelaceae), which produce the anthraquinone derivatives chrysophanol and its glycosides. The minor product chrysophanol 8-O-beta-gentiobioside was fully characterized by spectroscopic analysis and synthesis.


Assuntos
Aloe , Antraquinonas/química , Glicosídeos/química , Antraquinonas/isolamento & purificação , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Sementes , Técnicas de Cultura de Tecidos
9.
J Appl Toxicol ; 22(2): 107-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11920934

RESUMO

Taxus cuspidata and Taxus media var. Hicksii contain paclitaxel, among other taxoids, on the surface of the needles. These compounds were removed by 5-s dipping of the needles in water just below its boiling point at 96 degrees C and at 60 degrees C and 40 degrees C. Taxus cuspidata contained a fourfold higher concentration of paclitaxel than Taxus media var. Hicksii. The extract with the higher concentration of paclitaxel was more harmful to the mites Tetranychus urticae Koch, increasing their mortality 150%, prolonging development by ca. 20% and lowering the average fecundity from 112 in the control to 16.13 after treatment with Taxus cuspidata; also, the net reproductive rate dropped from 70.24 to 6.70, which is more than a tenfold reduction.


Assuntos
Ácaros/efeitos dos fármacos , Paclitaxel/farmacologia , Praguicidas/farmacologia , Taxus/química , Animais , Relação Dose-Resposta a Droga , Feminino , Fertilidade/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Paclitaxel/isolamento & purificação , Extratos Vegetais/química
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