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1.
Molecules ; 19(6): 7207-22, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24886944

RESUMO

Danshen, the dried roots of Salvia miltiorrhiza, is an extremely valued Traditional Chinese Medicine. Previously, we have demonstrated that salvianolic acid B (SaB), the important bioactive ingredient in this herb, was a post-harvest product. Here, we further reported that all salvianolic acids (SAs) in the roots were post-harvest products of the drying process. In addition, the results of various radical scavenging activity assays, including lipid peroxidation (1), DPPH (2), hydroxyl (3) and superoxide (4), were significantly increased along with the accumulation of total salvianolic acids in the process. The contents of chemical targets and antioxidant activities both reached the highest value under thermal treatment at 130 °C for 80 min. In this dehydration period, contents of SaB, and sum of nine SAs increased from 0.01% to 5.51%, and 0.20% to 6.61%; and IC50 of antioxidant activity decreased from 4.85 to 2.69 (1); 7.75 to 0.43 (2); 2.57 to 1.13 (3) and 17.25 to 1.10 mg/mL. These results further supported the hypothesis that the newly harvested plant roots were still physiologically active and the secondary metabolites might be produced due to dehydration stress after harvest. Our findings supplied an important and useful theoretical basis for promoting the quality of Danshen and other medicinal plant materials.


Assuntos
Alcenos/metabolismo , Antioxidantes/metabolismo , Raízes de Plantas/química , Polifenóis/metabolismo , Salvia miltiorrhiza/química , Salvia miltiorrhiza/metabolismo , Sequestradores de Radicais Livres/metabolismo
2.
Molecules ; 17(3): 2388-407, 2012 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-22370525

RESUMO

Drying is the most common and fundamental procedure in the post-harvest processing which contributes to the quality and valuation of medicinal plants. However, attention to and research work on this aspect is relatively poor. In this paper, we reveal dynamic variations of concentrations of five major bioactive components, namely salvianolic acid B (SaB), dihydrotanshinone I, cryptotanshinone, tanshinone I and tanshinone IIA, in roots of Salvia miltiorrhiza (Dashen) during the drying process at different oven temperatures. A minor amount of SaB was found in fresh materials while an noticeable increase in SaB was detected in drying at 50~160 °C. The maximal value occurred after 40 min of drying at 130 °C and its variation showed a reverse V-shaped curve. Production of SaB exhibited a significant positive correlation with drying temperatures and a significant negative correlation with sample moistures. The amounts of tanshinones were nearly doubled in the early stage of drying and their variations showed similar changing trends with drying temperatures and sample moistures. The results supported our speculation that postharvest fresh plant materials, especially roots, were still physiologically active organs and would exhibit a series of anti-dehydration mechanisms including production of related secondary metabolites at the early stage of dehydration. Hence, the proper design of drying processes could contribute to promoting rather than reducing the quality of Danshen and other similar medicinal plants.


Assuntos
Benzofuranos/metabolismo , Dessecação/métodos , Medicamentos de Ervas Chinesas/metabolismo , Raízes de Plantas/metabolismo , Salvia miltiorrhiza/metabolismo , Abietanos/química , Abietanos/isolamento & purificação , Abietanos/metabolismo , Benzofuranos/química , Benzofuranos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Medicina Tradicional Chinesa/métodos , Fenantrenos/química , Fenantrenos/isolamento & purificação , Fenantrenos/metabolismo , Raízes de Plantas/química , Salvia miltiorrhiza/química
3.
J Microbiol ; 46(5): 549-56, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18974957

RESUMO

Cordyceps sinensis is one of the most valuable medicinal caterpillar fungi native to China. However, its productivity is extremely limited and the species is becoming endangered. The genetic diversity of eighteen C. sinensis populations across its major distributing regions in China was evaluated by inter-simple sequence repeat (ISSR) markers. A total of 141 markers were produced in 180 individuals from the 18 populations, of which 99.3% were polymorphic. The low average of Shannon (0.104) and Nei index (0.07) of the 18 populations indicates that there are little genetic variations within populations. For all 18 populations, estimates of total gene diversity (H(T)), gene diversity within populations (H(S)), coefficient of genetic differentiation (G(ST)), and gene flow (Nm) were 0.170, 0.071, 0.583, and 0.357, respectively. This pattern suggests that the genetic diversity of C. sinensis is low and most of the ISSR variations are found among populations with little gene exchange. The 18 populations are divided into five groups based on the genetic distance and the grouping pattern matches with the geographic distribution along the latitudinal gradient. The five groups show obvious difference in the G(ST) and Nm values. Therefore, the genetic diversification of C. sinensis populations may be determined by geographic isolation and the combined effects of life history characters and the interaction with host insect species. The information illustrated by this study is useful for selecting in situ conservation sites of C. sinensis.


Assuntos
Cordyceps/genética , Variação Genética , Repetições Minissatélites , China , Cordyceps/classificação , Cordyceps/isolamento & purificação , Filogenia , Polimorfismo Genético
4.
Chem Biodivers ; 5(7): 1353-63, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18651621

RESUMO

Scutellaria baicalensis was collected from four wild and four cultivated populations from different locations in China. Forty-two samples were analyzed using random amplification of polymorphic DNA (RAPD) techniques for genetic profiling, and high performance liquid chromatography (HPLC) techniques to determine the flavonoid content. The selected 23 RAPD primers yielded a total of 838 clear and reproducible bands of which 237 were found to be polymorphic. The wild population exhibited higher polymorphism than that of the cultivated population. The dendrogram generated by the UPGMA method via Nei's genetic distance revealed three distinct genotypes from the cultivated populations and several branches from the wild populations. The contents of baicalin and wogonoside in dried roots of the samples ranged from (w/w) 8.63 to 17.84%, and from 1.99 to 4.21%, respectively, whereas their aglycones, baicalein and wogonin, were within the range of only 0.04-0.23%. The total content of the four flavonoids varied from 9.45 to 26.24%. Comparatively, the cultivated populations contained much higher levels of baicalin and total flavonoids than those in the wild populations. The results from genetic characterization and phytochemical analysis demonstrated that the quality variation of this drug was mainly determined by extrinsic environmental or agricultural factors, rather than by genetic differences. Our findings can be used for the commercial production and germplasm management of this medicinal plant.


Assuntos
Scutellaria baicalensis/genética , Cromatografia Líquida de Alta Pressão , Flavanonas/análise , Flavonoides/análise , Variação Genética , Glucosídeos/análise , Técnica de Amplificação ao Acaso de DNA Polimórfico , Scutellaria baicalensis/química
5.
Molecules ; 12(3): 312-7, 2007 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-17851390

RESUMO

Mistletonone, a novel diarylheptanoid, was isolated from the branches and leaves of Viscum coloratum (Kom.) Nakai (Loranthaceae). It was identified as 1,7-di-(p-hydroxyphenyl)-5-hydroxyl-cis-2,3-epoxy-1-one on the basis of spectral evidence. The compound showed significant scavenging effects on hydroxyl radicals and superoxide anion radicals in the direct assay using the electron spin resonance (ESR) technique.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Diarileptanoides/química , Diarileptanoides/isolamento & purificação , Compostos de Epóxi/química , Compostos de Epóxi/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação , Folhas de Planta/química , Caules de Planta/química , Viscum/química , Isótopos de Carbono , Espectroscopia de Ressonância de Spin Eletrônica , Sequestradores de Radicais Livres/química , Radical Hidroxila/química , Ressonância Magnética Nuclear Biomolecular , Prótons , Superóxidos/química
6.
Chem Pharm Bull (Tokyo) ; 54(1): 133-5, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16394568

RESUMO

Two new flavanone glucosides, (2S)-homoeriodictyol 7,4'-di-O-beta-D-glucopyranoside (4) and (2R)-eriodictyol 7,4'-di-O-beta-D-glucopyranoside (5) were isolated from the branches and leaves of Viscum coloratum (KOMAR) NAKAI (Loranthaceae), along with three known flavanone glucosides: (2S)-homoeriodictyol 7-O-beta-D-glucopyranoside (1), (2S)-eriodictyol 7-O-beta-D-glucopyranoside (2), and (2S)-naringenin 7-O-beta-D-glucopyranoside (3). The structures of these compounds were elucidated using spectroscopic methods. The antioxidant activities of these isolated compounds were evaluated by colorimetric methods based on their scavenging effects on hydroxyl radicals and superoxide anion radicals, respectively. All the compounds showed potent albeit varied degrees of antioxidative activities and the structure-activity relationship is discussed.


Assuntos
Antioxidantes/química , Flavanonas/química , Glucosídeos/química , Viscum/química , Antioxidantes/isolamento & purificação , Configuração de Carboidratos , Sequência de Carboidratos , Flavanonas/isolamento & purificação , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Glucosídeos/isolamento & purificação , Radical Hidroxila/química , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oxidantes/química , Extratos Vegetais/análise , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade , Superóxidos/química , Xantina Oxidase/química
7.
Chem Pharm Bull (Tokyo) ; 53(8): 1065-7, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16079552

RESUMO

A new orcinol glucoside, orcinol-1-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (3), was isolated from the rhizomes of Curculigo orchioides GAERTN., together with seven known compounds: orcinol glucoside (1), orcinol-1-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (2), curculigoside (4), curculigoside B (5), curculigoside C (6), 2,6-dimethoxyl benzoic acid (7), and syringic acid (8). The structures of these compounds were elucidated using spectroscopic methods. The antioxidant activities of these isolated compounds were evaluated by colorimetric methods based on their scavenging effects on hydroxyl radicals and superoxide anion radicals, respectively. All the compounds showed potent antioxidative activities and the structure-activity relationship is discussed.


Assuntos
Antioxidantes/isolamento & purificação , Curculigo/química , Glicosídeos/isolamento & purificação , Fenóis/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
8.
Phytochemistry ; 49(6): 1807-1809, 1998 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11711107

RESUMO

A new beta-carboline alkaloid, 1-acetyl-8-hydroxy-beta-carboline, was isolated from the fern, Hypodematium squamuloso-pilosum, along with a known compound, 1-acetyl-beta-carboline. Their structures were elucidated from spectral evidence. This is the first report of this type of alkaloid being found in ferns.

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