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1.
Zhongguo Zhong Yao Za Zhi ; 47(14): 3781-3787, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-35850835

RESUMO

Since the current identification method for Paeoniae Radix Alba is complex in operation and long time-consuming with high requirements for technicians, the present study employed Heracles NEO ultra-fast gas phase electronic nose(E-nose) technology to identify raw and sulfur-fumigated Paeoniae Radix Alba decoction pieces in order to establish a rapid identification method for sulfur-fumigated Paeoniae Radix Alba. The odors of raw Paeoniae Radix Alba and its sulfur-fumigated products were analyzed by Heracles NEO ultra-fast gas phase E-nose to obtain the odor chromatographic information. The chemometric model was established, and the data were processed by principal component analysis(PCA), discriminant function analysis(DFA), soft independent modeling of class analogy(SIMCA), and partial least squares discriminant analysis(PLS-DA). The differential compounds of raw and sulfur-fumigated samples were qualitatively analyzed based on the Kovats retention index and Arochembase. As revealed by the comparison of gas chromatograms of raw and sulfur-fumigated Paeoniae Radix Alba, the heights of several peaks in the chromatograms before and after sulfur fumigation changed significantly. The peak(No.8) produced by ethylbenzene disappeared completely due to sulfonation reaction in the process of sulfur fumigation, indicating that ethylbenzene may be the key component in the identification of Paeoniae Radix Alba and its sulfur-fumigated products. In PCA, DFA, SIMCA, and PLS-DA models, the two types of samples were separated into two different regions, indicating that the established models can clearly distinguish between raw and sulfur-fumigated Paeoniae Radix Alba. The results showed that Heracles NEO ultra-fast gas phase E-nose technology could realize the rapid identification of raw and sulfur-fumigated Paeoniae Radix Alba, which provides a new method and idea for the rapid identification of sulfur-fumigated Chinese medicine.


Assuntos
Medicamentos de Ervas Chinesas , Paeonia , Medicamentos de Ervas Chinesas/química , Nariz Eletrônico , Fumigação/métodos , Paeonia/química , Extratos Vegetais , Enxofre/química
2.
J Asian Nat Prod Res ; 23(11): 1085-1092, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34128433

RESUMO

A novel octahydroindolizine alkaloid, named dendrocrepidamine (1) with an unusual 18,19,19'-cyclopropanone-dendrocrepine skeleton, was isolated from the ethanol extract of the roots of Dendrobium crepidatum, along with six known compounds (2-7). The structure of 1 was elucidated through HR-ESIMS, NMR spectroscopic data and computational calculations. All compounds were examined for their inhibitory effects on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 cells with IC50 values in the range of 3.04-54.89 µM. In vivo, crepidatin (6) (80, 40 and 10 mg/kg) showed a significant protective effect against LPS-induced acute lung injury (ALI) in mice.


Assuntos
Alcaloides , Dendrobium , Alcaloides/farmacologia , Animais , Lipopolissacarídeos/farmacologia , Camundongos , Estrutura Molecular , Óxido Nítrico , Células RAW 264.7
3.
Artigo em Inglês | MEDLINE | ID: mdl-29735559

RESUMO

Muraymycins are antibacterial natural products from Streptomyces spp. that inhibit translocase I (MraY), which is involved in cell wall biosynthesis. Structurally, muraymycins consist of a 5'-C-glycyluridine (GlyU) appended to a 5″-amino-5″-deoxyribose (ADR), forming a disaccharide core that is found in several peptidyl nucleoside inhibitors of MraY. For muraymycins, the GlyU-ADR disaccharide is further modified with an aminopropyl-linked peptide to generate the simplest structures, annotated as the muraymycin D series. Two enzymes encoded in the muraymycin biosynthetic gene cluster, Mur29 and Mur28, were functionally assigned in vitro as a Mg·ATP-dependent nucleotidyltransferase and a Mg·ATP-dependent phosphotransferase, respectively, both modifying the 3″-OH of the disaccharide. Biochemical characterization revealed that both enzymes can utilize several nucleotide donors as cosubstrates and the acceptor substrate muraymycin also behaves as an inhibitor. Single-substrate kinetic analyses revealed that Mur28 preferentially phosphorylates a synthetic GlyU-ADR disaccharide, a hypothetical biosynthetic precursor of muraymycins, while Mur29 preferentially adenylates the D series of muraymycins. The adenylated or phosphorylated products have significantly reduced (170-fold and 51-fold, respectively) MraY inhibitory activities and reduced antibacterial activities, compared with the respective unmodified muraymycins. The results are consistent with Mur29-catalyzed adenylation and Mur28-catalyzed phosphorylation serving as complementary self-resistance mechanisms, with a distinct temporal order during muraymycin biosynthesis.


Assuntos
Proteínas de Bactérias/antagonistas & inibidores , Nucleosídeos/biossíntese , Nucleosídeos/química , Nucleotidiltransferases/química , Peptídeos/química , Fosfotransferases/química , Streptomyces/metabolismo , Transferases/antagonistas & inibidores , Antibacterianos/biossíntese , Nucleotídeos/biossíntese , Nucleotidiltransferases/genética , Fosforilação , Fosfotransferases/genética , Transferases (Outros Grupos de Fosfato Substituídos)
4.
J Asian Nat Prod Res ; 12(7): 576-81, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20628936

RESUMO

Three new lupane-type triterpenes, 3 alpha-O-trans-feruloylbetulinic acid (1), 3 alpha-O-trans-coumaroylbetulinic acid (2) and 3beta-O-cis-feruloylbetulin (3), together with 10 known triterpenes (4-13), were isolated from the aerial parts of the mangrove plant Ceriops tagal. The structures of the three new compounds were established by means of spectroscopic data analyses and chemical methods.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Rhizophoraceae/química , Triterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Triterpenos/química
5.
J Agric Food Chem ; 58(9): 5368-73, 2010 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-20297841

RESUMO

The phytochemical profiles of Morus nigra roots and twigs were compared by HPLC with those of the old and young twigs of Morus alba which are known to contain oxyresveratrol and mulberroside A as major components. It was found that M. nigra root extract contains some unknown natural products with potential tyrosinase inhibitory activity. The extract (95% ethanol) of the roots of M. nigra was further investigated in this study. One new compound, 5'-geranyl-5,7,2',4'-tetrahydroxyflavone, and twenty-eight known phenolic compounds were isolated. Their structures were identified by mass spectrometry and NMR spectroscopy. Nine compounds, 5'-geranyl-5,7,2',4'-tetrahydroxyflavone, steppogenin-7-O-beta-D-glucoside, 2,4,2',4'-tetrahydroxychalcone, moracin N, kuwanon H, mulberrofuran G, morachalcone A, oxyresveratrol-3'-O-beta-D-glucopyranoside and oxyresveratrol-2-O-beta-D-glucopyranoside, showed better tyrosinase inhibitory activities than kojic acid. It was noteworthy that the IC(50) values of 2,4,2',4'-tetrahydroxychalcone and morachalcone A were 757-fold and 328-fold lower than that of kojic acid, respectively, suggesting a great potential for their development as effective natural tyrosinase inhibitors.


Assuntos
Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Morus/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Relação Estrutura-Atividade
6.
Nat Prod Commun ; 5(1): 9-12, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20184010

RESUMO

A new dolabrane-type diterpene named tagalsin O 1, together with six known analogues 2-7, were isolated from the aerial part of the mangrove plant Ceriops tagal. The structures and relative configurations were elucidated on the basis of their spectroscopic data. Cytotoxicity of the isolated compounds against HeLa human cervical carcinoma cancer cell line was evaluated.


Assuntos
Diterpenos/isolamento & purificação , Rhizophoraceae/química , Antineoplásicos Fitogênicos/análise , Células HeLa , Humanos , Estrutura Molecular
7.
Org Lett ; 11(23): 5522-4, 2009 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-19894719

RESUMO

Jatrophalactam (1), a novel diterpenoid lactam possessing an unprecedented 5/13/3 tricyclic skeleton, was isolated from the roots of Jatropha curcas. The structure and relative configuration of jatrophalactam (1) were elucidated by extensive spectroscopic analysis and further determined by a single-crystal X-ray diffraction.


Assuntos
Diterpenos/isolamento & purificação , Jatropha/química , Lactamas/isolamento & purificação , Cristalografia por Raios X , Diterpenos/química , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lactamas/química , Lactamas/farmacologia , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química
8.
J Agric Food Chem ; 57(15): 6649-55, 2009 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-19588925

RESUMO

An HPLC method was developed and validated to compare the chemical profiles and tyrosinase inhibitors in the woods, twigs, roots, and leaves of Artocarpus heterophyllus . Five active tyrosinase inhibitors including dihydromorin, steppogenin, norartocarpetin, artocarpanone, and artocarpesin were used as marker compounds in this HPLC method. It was discovered that the chemical profiles of A. heterophyllus twigs and woods are quite different. Systematic chromatographic methods were further applied to purify the chemicals in the twigs of A. heterophyllus. Four new phenolic compounds, including one isoprenylated 2-arylbenzofuran derivative, artoheterophyllin A (1), and three isoprenylated flavonoids, artoheterophyllin B (2), artoheterophyllin C (3), and artoheterophyllin D (4), together with 16 known compounds, were isolated from the ethanol extract of the twigs of A. heterophyllus. The structures of compounds 1-4 were elucidated by spectroscopic analysis. However, the four new compounds did not show significant inhibitory activities against mushroom tyrosinase compared to kojic acid. It was found that similar compounds, such as norartocarpetin and artocarpesin in the twigs and woods of A. heterophyllus, contributed to their tyrosinase inhibitory activity.


Assuntos
Artocarpus/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Peptídeos/química , Extratos Vegetais/química , Agaricales/enzimologia , Proteínas Fúngicas/antagonistas & inibidores , Casca de Planta/química , Raízes de Plantas/química
9.
Steroids ; 2008 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-18840455

RESUMO

This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologises for any inconvenience this may cause.

10.
J Nat Prod ; 71(4): 674-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18303852

RESUMO

Five new lindenane sesquiterpene dimers ( 1- 5), named shizukaols K-O, and eight known sesquiterpene dimers were isolated from the roots of Chloranthus fortunei. The structures of 1- 5 were elucidated using spectroscopic data, mainly 1D NMR, 2D NMR, and mass spectra.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Magnoliopsida/química , Sesquiterpenos/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Sesquiterpenos/química
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