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1.
Planta Med ; 84(6-07): 442-448, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29121679

RESUMO

(Acetoxy-)valerenic acid and total essential oil content are important quality attributes of pharmacy grade valerian root (Valerianae radix). Traditional analysis of these quantities is time-consuming and necessitates (harmful) solvents. Here we investigated an application of attenuated total reflection Fourier transform infrared spectroscopy for extractionless analysis of these quality attributes on a representative sample comprising 260 wild-crafted individuals covering the Central European taxonomic diversity of the Valeriana officinalis L. s. l. species aggregate with its three major ploidy cytotypes (i.e., di-, tetra- and octoploid). Calibration models were built by orthogonal partial least squares regression for quantitative analysis of (acetoxy-)valerenic acid and total essential oil content. For the latter, we propose a simplistic protocol involving apolar extraction followed by gas chromatography as a reference method for multivariate calibration in order to handle the analysis of samples taken from individual plants. We found good predictive ability of chemometric models for quantification of valerenic acid, acetoxyvalerenic acid, total sesquiterpenoid acid, and essential oil content with a root mean squared error of cross-validation of 0.064, 0.043, and 0.09 and root mean squared error of prediction of 0.066, 0.057, and 0.09 (% content), respectively. Orthogonal partial least squares discriminant analysis revealed good discriminability between the most productive phenotype (i.e., the octoploid cytotype) in terms of sesquiterpenoid acids, and the less productive ones (i.e., di- and tetraploid). All in all, our results demonstrate the application of attenuated total reflection Fourier transform infrared spectroscopy for rapid, extractionless estimation of the most important quality attributes of valerian root and minimally invasive identification of the most productive phenotype in terms of sesquiterpenoid acids.


Assuntos
Valeriana/química , Indenos/análise , Óleos Voláteis/análise , Raízes de Plantas/química , Controle de Qualidade , Sesquiterpenos/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
2.
Phytomedicine ; 22(1): 213-22, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25636891

RESUMO

Epigallocatechin gallate (EGCG), ellagic acid (EA) and rosmarinic acid (RA) are natural polyphenols exerting cancer chemopreventive effects. Ribonucleotide reductase (RR; EC 1.17.4.1) converts ribonucleoside diphosphates into deoxyribonucleoside diphosphates being essential for DNA replication, which is why the enzyme is considered an excellent target for anticancer therapy. EGCG, EA, and RA dose-dependently inhibited the growth of human HL-60 promyelocytic leukemia cells, exerted strong free radical scavenging potential, and significantly imbalanced nuclear deoxyribonucleoside triphosphate (dNTP) concentrations without distinctly affecting the protein levels of RR subunits (R1, R2, p53R2). Incorporation of (14)C-cytidine into nascent DNA of tumor cells was also significantly lowered, being equivalent to an inhibition of DNA synthesis. Consequently, treatment with EGCG and RA attenuated cells in the G0/G1 phase of the cell cycle, finally resulting in a pronounced induction of apoptosis. Sequential combination of EA and RA with the first-line antileukemic agent arabinofuranosylcytosine (AraC) synergistically potentiated the antiproliferative effect of AraC, whereas EGCG plus AraC yielded additive effects. Taken together, we show for the first time that EGCG, EA, and RA perturbed dNTP levels and inhibited cell proliferation in human HL-60 promyelocytic leukemia cells, with EGCG and RA causing a pronounced induction of apoptosis. Due to these effects and synergism with AraC, these food ingredients deserve further preclinical and in vivo testing as inhibitors of leukemic cell proliferation.


Assuntos
Antineoplásicos/farmacologia , Catequina/análogos & derivados , Cinamatos/farmacologia , Citarabina/farmacologia , Depsídeos/farmacologia , Ácido Elágico/farmacologia , Trifosfato de Adenosina/química , Catequina/farmacologia , Proliferação de Células/efeitos dos fármacos , DNA/biossíntese , Sinergismo Farmacológico , Sequestradores de Radicais Livres/farmacologia , Células HL-60/efeitos dos fármacos , Humanos , Estrutura Molecular , Inibidores da Síntese de Ácido Nucleico/farmacologia , Nucleotídeos de Timina/química , Ácido Rosmarínico
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