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1.
PLoS One ; 13(11): e0207696, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30452471

RESUMO

Stellaria dichotoma var. lanceolata (SdLv), a member of the Caryophyllaceae, is a traditional herbal medicine that has been used to treat fever, night sweats, and malaria in East Asia. Inflammation plays an essential role in both host defense and pathogenesis during infection by diverse intracellular pathogens. Herein, we showed that an herbal extract from SdLv effectively attenuated inflammatory responses from infection of Mycobacterium abscessus (Mab), but not Toxoplasma gondii (T. gondii). In primary murine macrophages, Mab infection resulted in the rapid activation of nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK), as well as in the generation of proinflammatory cytokines, such as tumor necrosis factor α and interleukin-6, which were all significantly inhibited by pretreatment with SdLv. However, herbal extracts from Bupleurum chinense DC. (Buch) or Bupleurum falcatum L. (Bufa) did not affect M. abs-induced activation of proinflammatory responses. Importantly, we demonstrated that generation of intracellular reactive oxygen species, which are important signaling intermediaries in the activation of NF-κB and the MAPK signaling pathway, was rapidly increased in Mab-infected macrophages, and this was effectively suppressed by pretreatment with SdLv, but not Buch and Bufa. We further found that the treatment of Buch and Bufa, but not SdLv, led to the activation of NF-κB and the MAPK signaling pathway and the generation of intracellular reactive oxygen species. Moreover, oral administration of SdLv significantly reduced lethality in Mab-infected mice. Collectively, these results suggest the possible use of SdLv as an effective treatment for Mab infection.


Assuntos
Anti-Inflamatórios/farmacologia , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Extratos Vegetais/farmacologia , Stellaria/química , Animais , Anti-Inflamatórios/química , Bupleurum/química , Linhagem Celular , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mycobacterium abscessus/efeitos dos fármacos , NF-kappa B/metabolismo , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo
2.
Environ Monit Assess ; 189(12): 622, 2017 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-29124423

RESUMO

Intercropping affects heavy-metal uptake in plants. In this study, three cadmium (Cd)-accumulator species (Stellaria media, Malachium aquaticum, and Galium aparine) were intercropped together in Cd-contaminated soil to study the effects of intercropping on co-remediation. Mutual intercropping significantly increased the biomasses of S. media, M. aquaticum, and G. aparine compared with their respective monocultures. The photosynthetic pigment contents of three species were not significantly affected by mutual intercropping. Mutual intercropping did not increase the Cd contents in roots and shoots of G. aparine, but it increased the Cd contents in roots of S. media and M. aquaticum. It also decreased the Cd contents in shoots of S. media and M. aquaticum. Only G. aparine intercropped with M. aquaticum and three-species intercropping increased Cd-accumulation levels in whole plants of each species. Only S. media intercropped with M. aquaticum and three-species intercropping increased the Cd accumulation at the whole plant level in every plant in a single pot, with S. media intercropped with M. aquaticum showing the greatest increase. Therefore, S. media intercropped with M. aquaticum and three-species intercropping may improve the efficiency of phytoremediation of Cd-contaminated soil, with S. media intercropped with M. aquaticum representing the best combination.


Assuntos
Biodegradação Ambiental , Cádmio/análise , Galium/metabolismo , Poluentes do Solo/análise , Stellaria/metabolismo , Biomassa , Cádmio/metabolismo , Monitoramento Ambiental , Galium/química , Metais Pesados , Raízes de Plantas/química , Plantas , Poluentes do Solo/metabolismo , Stellaria/química
3.
Biochimie ; 116: 125-32, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26196691

RESUMO

A novel peptide named SmAMP3 was isolated from leaves of common chickweed (Stellaria media L.) by a combination of acidic extraction and a single-step reversed-phase HPLC and sequenced. The peptide is basic and cysteine-rich, consists of 35 amino acids, and contains three disulphide bridges. Homology search revealed that SmAMP3 belongs to the family of hevein-like antimicrobial peptides carrying a conserved chitin-binding site. Efficient binding of chitin by SmAMP3 was proved by in vitro assays. Molecular modeling confirmed conservation of the chitin-binding module in SmAMP3 locating the variable amino acid residues to the solvent-exposed loops of the molecule. The peptide exhibits potent antifungal activity against important plant pathogens in the micromolar range, although it is devoid of antibacterial activity at concentrations below 10 µM. As judged by chromatographic behavior and mass spectrometric data, the peptide is constitutively expressed in above-ground organs and seeds of S. media plants, thus representing an important player in the preformed branch of the plant immune system.


Assuntos
Antifúngicos/química , Folhas de Planta/química , Stellaria/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antifúngicos/farmacologia , Quitina/metabolismo , Testes de Sensibilidade Microbiana , Peptídeos/química , Peptídeos/farmacologia , Proteínas de Plantas/química , Proteínas de Plantas/farmacologia
4.
Nat Prod Commun ; 10(3): 437-40, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25924523

RESUMO

Stellaria nemorum L. and S. holostea L. (Caryophyllaceae) were investigated for their flavonoids. The new flavonoid 6-C-[(α-arabinopyranosyl)-( 1-->2)-O-ß- xylopyranosyl]apigenin (1) and the four known C-glycosides, 6-C-[(α-arabinopyranosyl)-(1-->2)-O-ß-glucopyranosyl]apigenin (2), apigenin 6-C-ß- galactopyranoside-8-C-ß-glucopyranoside (3), apigenin 6-C-ß-glucopyranoside-8-C-α-arabinopyranoside (4), and apigenin 6-C-ß-glucopyranoside-8-C-ß- xylopyranoside (5) were isolated from the aerial parts of S. nemorum for the first time. Furthemore, five known flavonoids, 3,5,7-trihydroxy-3',5'- dimethoxyflavone (9), diosmetin 6-C-ß-glucopyranoside (8), schaftoside (4), isoorientin (6) and orientin (7) were obtained from the aerial parts of S. holostea. Compounds 4, 8 and 9 are reported for the first time from this species. The structures of all isolated compounds were unambiguously elucidated by one- and two- dimensional NMR and mass spectral analysis, by acid hydrolysis, as well as by comparison with literature data. The crude extracts of the investigated species exhibited antimicrobial activity against Staphylococcus aureus, while none of the isolated compounds was found to be active.


Assuntos
Flavonoides/química , Stellaria/química , Estrutura Molecular , Especificidade da Espécie
5.
Plant Mol Biol ; 84(1-2): 189-202, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24081691

RESUMO

Plant defense against disease is a complex multistage system involving initial recognition of the invading pathogen, signal transduction and activation of specialized genes. An important role in pathogen deterrence belongs to so-called plant defense peptides, small polypeptide molecules that present antimicrobial properties. Using multidimensional liquid chromatography, we isolated a novel antifungal peptide named Sm-AMP-X (33 residues) from the common chickweed (Stellaria media) seeds. The peptide sequence shows no homology to any previously described proteins. The peculiar cysteine arrangement (C(1)X3C(2)XnC(3)X3C(4)), however, allocates Sm-AMP-X to the recently acknowledged α-hairpinin family of plant defense peptides that share the helix-loop-helix fold stabilized by two disulfide bridges C(1)-C(4) and C(2)-C(3). Sm-AMP-X exhibits high broad-spectrum activity against fungal phytopathogens. We further showed that the N- and C-terminal "tail" regions of the peptide are important for both its structure and activity. The truncated variants Sm-AMP-X1 with both disulfide bonds preserved and Sm-AMP-X2 with only the internal S-S-bond left were progressively less active against fungi and presented largely disordered structure as opposed to the predominantly helical conformation of the full-length antifungal peptide. cDNA and gene cloning revealed that Sm-AMP-X is processed from a unique multimodular precursor protein that contains as many as 12 tandem repeats of α-hairpinin-like peptides. Structure of the sm-amp-x gene and two related pseudogenes sm-amp-x-ψ1 and sm-amp-x-ψ2 allows tracing the evolutionary scenario that led to generation of such a sophisticated precursor protein. Sm-AMP-X is a new promising candidate for engineering disease resistance in plants.


Assuntos
Antifúngicos/metabolismo , Proteínas de Plantas/biossíntese , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Stellaria/química , Sequência de Aminoácidos , Antifúngicos/química , Clonagem Molecular , Evolução Molecular , Fungos/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/fisiologia , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Sementes/química , Sementes/genética , Stellaria/metabolismo
6.
Bull Exp Biol Med ; 154(5): 645-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23658890

RESUMO

Therapy of rats with CCl4 hepatitis with Stellaria media L. water-soluble polysaccharide fraction in a dose of 100 mg/kg reduces serum activities of transaminases (ALT and AST), alkaline phosphatase, bilirubin, and the thymol test values. In the liver, the density of inflammatory infiltration of the organ parenchyma, total count of necrotic hepatocytes, fatty and protein degeneration are reducing. Hence, water-soluble polysaccharide fraction, isolated from the terrestrial part of Stellaria media L., is characterized by hepatoprotective activity.


Assuntos
Hepatite/tratamento farmacológico , Fígado/efeitos dos fármacos , Preparações de Plantas/uso terapêutico , Stellaria/química , Alanina Transaminase/sangue , Alanina Transaminase/metabolismo , Fosfatase Alcalina/sangue , Fosfatase Alcalina/metabolismo , Animais , Aspartato Aminotransferases/sangue , Aspartato Aminotransferases/metabolismo , Bilirrubina/sangue , Bilirrubina/metabolismo , Tetracloreto de Carbono , Hepatócitos/efeitos dos fármacos , Fígado/patologia , Testes de Função Hepática , Masculino , Fitoterapia , Polissacarídeos/uso terapêutico , Ratos , Solubilidade , Timolftaleína/análogos & derivados
7.
BMC Complement Altern Med ; 12: 145, 2012 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-22943464

RESUMO

BACKGROUND: Obesity is recognized as a social problem, associated with serious health risks and increased mortality. Numerous trials have been conducted to find and develop new anti-obesity drugs through herbal sources to minimize side effects associated with the present anti-obesity drugs. The present study was designed to evaluate the quality control parameters, quantitative phytochemical analysis (total phenolic, total flavonoids and total saponin content), and the anti-obesity effect of lyophilized juice (LJ) of Stellaria media (Linn.) Vill. by employing in vitro and in vivo models. METHODS: In vitro studies were performed to evaluate the inhibitory activity of LJ on pancreatic amylase and lipase. The in vivo pancreatic lipase activity was evaluated by measurement of plasma triacylglycerol levels after oral administration of lipid emulsion to swiss albino mice. Furthermore, the anti-obesity effect of LJ was assessed at two doses, 400 mg/kg and 900 mg/kg body weight in mice fed a high-fat-diet with or without LJ for 6 weeks. RESULTS: The LJ inhibited pancreatic amylase and lipase activity in vitro and elevated plasma triacylglycerol level in mice. LJ suppressed the increase in body weight, retroperitoneal adipose tissue, liver weights and serum parameters viz., total cholesterol, total triglyceride, LDL-cholesterol level at the dose of 900 mg/kg body weight of the mice fed with high fat diet. The total phenolic, flavonoid and saponin contents were found to be 0.26 mg/g, 1.4 mg/g and 1.19 µg/g respectively of LJ. CONCLUSION: The anti-obesity effects of LJ in high-fat-diet fed mice may be partly mediated through delaying the intestinal absorption of dietary fat and carbohydrate by inhibiting digestive enzymes.


Assuntos
Fármacos Antiobesidade/administração & dosagem , Obesidade/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Stellaria/química , Amilases/metabolismo , Animais , Colesterol/sangue , Avaliação Pré-Clínica de Medicamentos , Lipase/metabolismo , Masculino , Camundongos , Obesidade/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/enzimologia , Triglicerídeos/sangue
8.
Food Chem Toxicol ; 50(12): 4461-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23009884

RESUMO

One of the dietary components in the New Nordic Diet, is plants from the wild countryside. However, these may have a high content of bioactive components, some of which could be toxic in larger quantities. The objective of this paper is to outline a strategy for safety evaluation of wild plants not covered in current food compositional databases and to apply the method for selected plants used in the New Nordic Diet recipes. Four examples of typical wild edible plants were evaluated (stinging nettle, sorrel, chickweed and common lambsquarters), and based on substantial equivalence with known food plants the majority of the bioactive components reported were within the range experienced when eating or drinking typical food stuffs. For most compounds the hazards could be evaluated as minor. The only precaution found was for common lambsquarters because of its presumed high level of oxalic acid. It is concluded that a substance-by-substance evaluation of intake by equivalence to common foods is a useful and efficient strategy to evaluate the safety of newly introduced wild edible plants. Further evaluation and better compositional analyses are warranted before a daily consumption of significant amounts of wild edible plants can be generally regarded as safe.


Assuntos
Dieta , Valor Nutritivo , Plantas Comestíveis/efeitos adversos , Plantas Comestíveis/química , Chenopodium album/química , Qualidade de Produtos para o Consumidor , Humanos , Medição de Risco , Rumex/química , Stellaria/química , Urtica dioica/química
9.
Molecules ; 17(7): 8633-46, 2012 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-22810196

RESUMO

Stellaria media (Linn.) Villars is a traditional Chinese medicine that has been used for over 200 years, mainly for the treatment of dermatitis and other skin diseases. It has also been used as an anti-viral agent. All the fresh chickweed juice samples used in this study were prepared using macroporous resin and ultrafiltration technology. The anti-hepatitis B virus (HBV) activity of S. media was evaluated in vitro using the human HBV-transfected liver cell line HepG2.2.15. The concentrations of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in HepG2.2.15 cell culture medium were determined by enzyme-linked immunosorbent assay (ELISA) after S. media-n (SM-n) treatment for 6 or 9 days. HBV DNA was quantified using transcription-mediated amplification and real-time polymerase chain reaction. In HepG2.2.15 cells, 30 µg/mL SM-3 effectively suppressed the secretion of HBsAg and HBeAg with inhibition rates of 27.92% and 25.35% after 6 days of treatment, respectively. Consistent with the reduction in HBV antigens, SM-3 also reduced the level of HBV DNA in a dose-dependent manner. The characterization and quantitation of the chemical composition of SM-3 showed the presence of flavonoid C-glycosides, polysaccharides, and protein, which exhibited diverse antiviral activities. In conclusion, our results demonstrate that SM-3 possesses potential anti-HBV activity in vitro. This is the first report demonstrating the anti-HBV effects of S. media, which is currently under early development as a potential anti-HBV drug candidate.


Assuntos
Antivirais , Medicamentos de Ervas Chinesas , Vírus da Hepatite B/efeitos dos fármacos , Stellaria/química , Antivirais/química , Antivirais/farmacologia , DNA Viral/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Células Hep G2 , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/análise , Antígenos E da Hepatite B/análise , Humanos
10.
Biochimie ; 93(3): 450-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21056078

RESUMO

Two novel highly homologous defensins, Sm-AMP-D1 and Sm-AMP-D2, were isolated from seeds of common chickweed Stellaria media L. (family Cariophyllaceae). They show sequence homology to defensins of the Brassicaceae plants and display strong inhibitory activity against phytopathogenic fungi and oomycetes in the micromolar range (IC(50)≤1µM). The cDNA sequences coding for Sm-AMP-D1 and Sm-AMP-D2 were obtained. They code for highly homologous precursor proteins, consisting of a signal peptide of 32 amino acid residues and the mature peptide domain of 50 amino acid residues. The Sm-AMP-D1 and Sm-AMP-D2 precursors differ by two amino acids: one in the signal peptide region, and the other, in the mature peptide domain. Two Sm-D1-encoding genes were identified in S. media genome by PCR amplification from the genomic DNA using Sm-D1-specific primers. They contain a single 599-bp intron in the signal peptide domain and differ from each other by nucleotide substitutions in the intron and 3'-untranslated regions, while the coding sequences are well conserved. One of the genes matched perfectly the sm-D1 cDNA sequence. The sm-D genes show promise for engineering pathogen resistance in crops and expand our knowledge on weed genomics.


Assuntos
Antifúngicos/isolamento & purificação , Defensinas/genética , Defensinas/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Sementes/química , Stellaria/química , Sequência de Aminoácidos , Antifúngicos/química , Antifúngicos/farmacologia , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Defensinas/química , Defensinas/isolamento & purificação , Fungos/efeitos dos fármacos , Genoma de Planta/genética , Genômica , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/farmacologia , Sementes/genética , Análise de Sequência de DNA , Stellaria/genética
11.
J Nat Prod ; 73(12): 1993-8, 2010 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-21090796

RESUMO

The present investigation on the chemical constituents of the roots of Stellaria dichotoma var. lanceolata has resulted in the isolation of 21 ß-carboline alkaloids, including 13 new compounds, dichotomides III-XIV (1-12) and dichotomine E (13), and eight known compounds. The structures of the new compounds were established on the basis of spectroscopic data analysis. Among these isolated alkaloids, five compounds were examined for their anti-inflammatory potential for the inhibition of NO production in LPS-treated RAW 264.7 cells. All compounds tested exhibited significant inhibition of NO production, with IC(50) values in the range of 11.3 to 19.3 µM.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Carbolinas/isolamento & purificação , Carbolinas/farmacologia , Stellaria/química , Alcaloides/química , Animais , Anti-Inflamatórios não Esteroides/química , Carbolinas/química , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Raízes de Plantas , Estereoisomerismo , Taiwan
12.
J Biosci Bioeng ; 110(2): 262-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20547324

RESUMO

Stellera chamaejasme has been used as a therapeutic plant for treatment of various inflammatory diseases and solid tumors. Our study was particularly interested in the differentiation inducing activity of the aerial parts of S.chamaejasme using human chronic leukemia cell line K562. The ethanol extract has been shown to be highly cytotoxic against K562 cells at >0.008% (v/v) doses. Cell cycle arrest at G(0)/G(1) phase, not detectable DNA fragmentation as well as positive staining with acridine orange and expression of beclin-1 protein in the treated cells led as to detect autophagic cell death during the plant extract treatment of K562 cells. Moreover, differentiation marker CD11b was also expressed in the treated cells.


Assuntos
Autofagia/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Stellaria/química , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Células K562
13.
Nat Prod Res ; 23(14): 1274-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19735039

RESUMO

One new triterpenoid, 3beta, 16beta, 23, 28-tetrahydroxy oleana-11, 13(18)-dien-3-O-beta-D-glucopyranosyl(1 --> 3) [beta-D-glucopyranosyl(1 --> 2)]-beta-D-fucopyranoside (1), together with two known flavonoids, were isolated from Stellaria media (L.) Cyr. The structure elucidation of the new compound was primarily based on HREIMS, EIMS, UV, IR, 1D- and 2D-NMR analyses, including COSY, HMQC and HMBC correlations.


Assuntos
Flavonoides/química , Stellaria/química , Triterpenos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
14.
Plant Foods Hum Nutr ; 64(1): 25-31, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19016328

RESUMO

UNLABELLED: The aim of this investigation was to study the antioxidant and anticancer activities of young sprouts of some traditional Korean salad plants. Total phenolics, antioxidant and anticancer activities of the methanol extracts from young sprouts of 11 salad plants were determined. The highest amount of phenolics was found in methanol extracts of Euonymus alatus (235.7 mg kg(-1)), followed by Hypericum ascyron (197.1 mg kg(-1)), Zanthoxylum piperitum (194.1 mg kg(-1)) and Zanthoxylum schinifolium (142.5 mg kg(-1)). Methanol extracts of E. alatus, H. ascyron, and Z. piperitum at 63 mg kg(-1) exhibited the highest dose-depend DPPH radical scavenging activity by 91.2, 91.2 and 83.9%, respectively. According to the MTT results, the methanol extracts from Stellaria aquatica, Eleutherococcus sessilifolrus and Z. schinifolium showed the highest anticancer activities against Calu-6 (IC50<25.0 microg ml(-1)) and from S. aquatica-the highest anticancer activities against SNU-601 (153.3 microg ml(-1)), following by E. sessilifolrus (196.7 microg ml(-1)) and Amaranthus mangostanus (303.1 microg ml(-1)). Total phenolics were highly correlated with the DPPH, suggesting that they contribute to the antioxidant properties of the studied plants. IN CONCLUSION: young sprouts of Korean salad possess antioxidant and anticancer properties and could be used as a supplement to proper drugs.


Assuntos
Antineoplásicos Fitogênicos/análise , Antioxidantes/análise , Fenóis/análise , Extratos Vegetais/análise , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Eleutherococcus/química , Euonymus/química , Sequestradores de Radicais Livres , Hypericum/química , Coreia (Geográfico) , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Especificidade da Espécie , Stellaria/química , Zanthoxylum/química
15.
J Med Food ; 11(4): 723-32, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19053866

RESUMO

The antioxidant properties of enzymatic extracts from Stellaria dichotoma were evaluated using seven carbohydrases (Promozyme, Celluclast, Maltogenase, Viscozyme, Termamyl, Dextrozyme, and AMG 300L) and five proteases (Protamex, Flavourzyme, Neutrase, pancreatic trypsin, and Alcalase) (all from Novo Co., Novozyme Nordisk, Bagsvaerd, Denmark) for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical, and alkyl radical scavenging activity using an electron spin resonance spectrometer. The DPPH radical scavenging activities of pancreatic trypsin and Celluclast extracts from S. dichotoma were the highest among various protease and carbohydrate extracts, and the 50% inhibitory concentration (IC(50)) values were 10.45 and 13.80 microg/mL, respectively. The Flavourzyme and Promozyme extracts of S. dichotoma showed the highest hydroxyl radical scavenging activities among the tested protease and carbohydrase extracts, with IC(50) values of 1.51 and 1.23 microg/mL, respectively. The S. dichotoma enzymatic extracts also exhibited alkyl radical scavenging activity in a dose-dependent manner. In addition, the ability of the enzymatic extracts to inhibit the oxidative damage of DNA was assessed in vitro by measuring the conversion of supercoiled pBR322 plasmid DNA to the open circular form. It was found that the enzymatic extracts could significantly and dose-dependently protect against hydroxyl radical-induced DNA damage. These results indicate that enzymatic extracts of S. dichotoma possess potent antioxidant activity.


Assuntos
Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Enzimas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteínas de Plantas/farmacologia , Stellaria/química , Compostos de Bifenilo/metabolismo , Relação Dose-Resposta a Droga , Espectroscopia de Ressonância de Spin Eletrônica , Enzimas/química , Enzimas/isolamento & purificação , Radicais Livres/metabolismo , Glicosídeo Hidrolases , Hidrazinas/metabolismo , Hidrólise , Peptídeo Hidrolases , Fenol/metabolismo , Fitoterapia , Picratos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação
16.
J Nat Prod ; 71(11): 1833-6, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18855444

RESUMO

While classic raffinose family oligosaccharides (RFOs) such as raffinose and stachyose are common in plants, stachyose is absent in the Caryophyllaceae. Instead the tetrasaccharide lychnose α-d-Gal-(1→6)α-d-Glc-(1→2)ß-d-Fru-(1→1)α-d-Gal can accumulate. Stellaria media, a representative member of this family, was used to isolate α-d-Gal-(1→6)-[α-d-Gal-(1→4)]α-d-Glc-(1→2)ß-d-Fru-(1→1)α-d-Gal, a novel pentasaccharide with a lychnose backbone. Complete NMR characterization using COSY, HSQC, HSQC-TOCSY, HMBC, and NOESY experiments was performed to unequivocally resolve its structure. This is the first report of a natural compound containing a Gal α(1→4)Glc linkage. The trivial name stellariose is proposed for this new pentasaccharide.


Assuntos
Oligossacarídeos/isolamento & purificação , Stellaria/química , Sequência de Carboidratos , Estrutura Molecular , Oligossacarídeos/química , Rafinose/química , Rafinose/isolamento & purificação
17.
Chem Biodivers ; 5(7): 1419-24, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18649308

RESUMO

A new 3,3''-biflavanone, isosikokianin A, was isolated from the roots of Stellera chamaejasme, together with eleven known compounds. Their structures and configurations were elucidated by spectroscopic methods including 2D-NMR techniques. Sikokianin A, chamaechromone, and quercetin showed in vitro antiviral activity against HBsAg secretion.


Assuntos
Antivirais/farmacologia , Biflavonoides/farmacologia , Cumarínicos/farmacologia , Flavonoides/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Stellaria/química , Biflavonoides/química , Cumarínicos/química , Flavonoides/química , Antígenos de Superfície da Hepatite B/efeitos dos fármacos , Antígenos E da Hepatite B/efeitos dos fármacos , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química
18.
Zhongguo Zhong Yao Za Zhi ; 32(11): 1048-51, 2007 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-17672340

RESUMO

OBJECTIVE: To study the chemical constituents of Stellaria media. METHOD: The compounds were isolated with various column chromatography and semi-preparative HPLC. The structures were determined by modem spectroscopic methods (IR, UV, 1H-NMR, 13C-NMR, HMBC, ESI-MS). RESULT: Five compounds were isolated and identified as apigenin 6-C-beta-D-galactopyranosyl-8-C-alpha-L-arabinopyranoside (1), apigenin 6-C-alpha-L-arabinopyranosyl-8-C-beta-D-galactopyranoside (2), apigenin 6-C-beta-D-galactopyranosyl-8-C-beta-L-arabinopyranoside (3), apigenin 6-C-beta-D-glucopyranosyl-8-C-beta-D-galactopyranoside (4), apigenin 6, 8-di-C-alpha-L-arabinopyranoside (5). CONCLUSION: Compounds 1-5 were obtained from Stellaria genus for the first time.


Assuntos
Apigenina/isolamento & purificação , Flavonas/isolamento & purificação , Galactosídeos/isolamento & purificação , Plantas Medicinais/química , Stellaria/química , Apigenina/química , Cromatografia Líquida de Alta Pressão/métodos , Flavonas/química , Galactosídeos/química
19.
Carbohydr Res ; 341(16): 2744-50, 2006 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-16997290

RESUMO

Lychnose (alpha-D-Gal-(1-->6)-alpha-D-Glc-(1-->2)-beta-D-Fru-(1-->1)-alpha-D-Gal) was isolated from Stellaria media, a representative member of the Caryophyllaceae plant family. Weak acid hydrolysis, enzymatic hydrolysis and complete NMR characterization were performed to confirm the identity of the tetrasaccharide. All (1)H and (13)C resonances were unambiguously assigned and the conformation of the sugars was determined using one and two dimensional NMR techniques. Anomeric characterizations in lychnose were confirmed from HMBC and NOESY spectra.


Assuntos
Oligossacarídeos/química , Stellaria/química , Configuração de Carboidratos , Sequência de Carboidratos , Dados de Sequência Molecular , Ressonância Magnética Nuclear Biomolecular , Caules de Planta/química
20.
J Nat Prod ; 68(11): 1686-8, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16309326

RESUMO

Two new cyclic peptides, dichotomins J (1) and K (2), have been isolated from the roots of Stellaria dichotoma, and their structures were elucidated by chemical degradation and extensive 2D NMR methods. Dichotomins J (1) and K (2) showed a moderate vasorelaxant effect on rat aorta.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Peptídeos Cíclicos/isolamento & purificação , Plantas Medicinais/química , Stellaria/química , Vasodilatadores/isolamento & purificação , Animais , Aorta/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Estrutura Molecular , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Raízes de Plantas/química , Ratos , Vasodilatadores/química , Vasodilatadores/farmacologia
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