Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Nat Prod ; 77(3): 521-6, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24479468

RESUMO

Continuing investigation of fractions from a supercritical fluid extract of Chinese licorice (Glycyrrhiza uralensis) roots has led to the isolation of 12 phenolic compounds, of which seven were described previously from this extract. In addition to these seven metabolites, four known components, 1-methoxyerythrabyssin II (4), 6,8-diprenylgenistein, gancaonin G (5), and isoglycyrol (6), and one new isoflavan, licorisoflavan C (7), were characterized from this material for the first time. Treatment of licoricidin (1) with palladium chloride afforded larger amounts of 7 and also yielded two new isoflavans, licorisoflavan D (8), which was subsequently detected in the licorice extract, and licorisoflavan E (9). Compounds 1-9 were evaluated for their antibacterial activities against the cariogenic Streptococcus mutans and the periodontopathogenic Porphyromonas gingivalis. Licoricidin (1), licorisoflavan A (2), and 7-9 showed antibacterial activity against P. gingivalis (MICs of 1.56-12.5 µg/mL). The most potent activity against S. mutans was obtained with 7 (MIC of 6.25 µg/mL), followed by 1 and 9 (MIC of 12.5 µg/mL). This study provides further evidence for the therapeutic potential of licorice extracts for the treatment and prevention of oral infections.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Glycyrrhiza uralensis/química , Isoflavonas/isolamento & purificação , Isoflavonas/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Piranos/isolamento & purificação , Piranos/farmacologia , Streptococcus mutans/efeitos dos fármacos , Antibacterianos/química , Benzopiranos/química , Genisteína/análogos & derivados , Genisteína/química , Alemanha , Glycyrrhiza/metabolismo , Isoflavonas/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Paládio/farmacologia , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Raízes de Plantas/química , Pterocarpanos/química , Pterocarpanos/isolamento & purificação , Piranos/química
2.
Psychol Assess ; 25(3): 979-90, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23815107

RESUMO

Dynamic risk variables (or criminogenic needs; Andrews & Bonta, 2003) increase risk for criminal behavior and are conceptualized as changeable through intervention. Yet this assumption of changeability has been examined in only a few studies, and none of these studies have examined whether the measurement properties the risk assessments measure remain invariant over time--a necessary precursor to determining if actual change is occurring or if changes in measurement are producing differences. This study examines the dynamic needs index (DNI) and protective strengths index (PSI) of the inventory of offender risk, needs, and strengths (Miller, 2006b) pre- and post-treatment. Findings suggest the measurement properties of the DNI are acceptably invariant over time, although there is evidence that the intercept of the alcohol/drug Problems scale is higher after (opposed to before) treatment and the intercept of the Intra/Interpersonal Problems scale is higher before treatment. Subsequent latent difference score models suggest--as expected--that the dynamic needs latent variable decreased and the protective strengths latent variable increased through treatment. This study presents first evidence for invariance of measurement properties of a risk assessment measure at different points in treatment.


Assuntos
Crime/psicologia , Psicologia Criminal/métodos , Testes Psicológicos , Adolescente , Adulto , Crime/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prisioneiros/psicologia , Medição de Risco , Autorrelato , Adulto Jovem
3.
PLoS One ; 7(7): e38563, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22802929

RESUMO

BACKGROUND: This study assessed the short and the long term safety of the 2009 AS03 adjuvanted monovalent pandemic vaccine through an active web-based electronic surveillance. We compared its safety profile to that of the seasonal trivalent inactivated influenza vaccine (TIV) for 2010-2011. METHODOLOGY/PRINCIPAL FINDINGS: Health care workers (HCW) vaccinated in 2009 with the pandemic vaccine (Arepanrix ® from GSK) or HCW vaccinated in 2010 with the 2010-2011 TIV were invited to participate in a web-based active surveillance of vaccine safety. They completed two surveys the day-8 survey covered the first 7 days post-vaccination and the day-29 survey covered events occurring 8 to 28 days after vaccination. Those who reported a problem were called by a nurse to obtain details. The main outcome was the occurrence of a new health problem or the worsening of an existing health condition that resulted in a medical consultation or work absenteeism. For the pandemic vaccine, a six-month follow-up for the occurrence of serious adverse events (SAE) was conducted. Among the 6242 HCW who received the pandemic vaccine, 440 (7%) reported 468 events compared to 328 of the 7645 HCW (4.3%) who reported 339 events after the seasonal vaccine. The 2009 pandemic vaccine was associated with significantly more local reactions than the 2010-2011 seasonal vaccine (1% vs. 0.03%, p<0.001). Paresthesia was reported by 7 HCW (0.1%) after the pandemic vaccine but by none after the seasonal vaccine. For the pandemic vaccine, no clustering of SAE was found in the 6 month follow-up. CONCLUSION: The 2009 pandemic vaccine seems to have a good safety profile, similar to the 2010-2011 TIV, with the exception of local reactions. This surveillance was adequately powered to identify AE associated with an excess risk ≥1 per 1000 vaccinations but is insufficient to detect rare AE. TRIAL REGISTRATION: ClinicalTrials.gov NCT01289418, NCT01318876.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/efeitos adversos , Adjuvantes Imunológicos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Pessoal de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Parestesia/induzido quimicamente
4.
J Med Food ; 15(12): 1045-50, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22738124

RESUMO

Periodontal diseases are a group of multifactorial polymicrobial infections characterized by a progressive inflammatory destruction of the periodontium. Flavonoids, including anthocyanins, are receiving increasing attention because of their promising human health benefits. The aim of our study was to investigate the effect of anthocyanins, pure or as part of a standardized black currant extract, on nicotine-induced cytotoxicity and lipopolysaccharide (LPS)-induced inflammatory responses in human cells. Using a colorimetric assay that measures cell viability, it was found that a pretreatment with an anthocyanin-rich black currant extract or cyanidin-3-O-glucoside neutralized the cytotoxic effect of nicotine on epithelial cells and fibroblasts in a dose-dependent manner. The black currant extract and cyanidin-3-O-glucoside also inhibited the LPS-induced secretion of interleukin-6 by human macrophages. The results of the present study suggest that black currant extract and cyanidin-3-O-glucoside may be promising candidates for the development of novel therapies to prevent and/or to treat smoking-related periodontal diseases.


Assuntos
Antocianinas/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Citoproteção , Glucosídeos/farmacologia , Ribes/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Frutas , Humanos , Interleucina-6/metabolismo , Lipopolissacarídeos/efeitos adversos , Macrófagos/efeitos dos fármacos , Nicotina/efeitos adversos , Extratos Vegetais/farmacologia
5.
J Breath Res ; 6(1): 016006, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22368239

RESUMO

Halitosis affects a large proportion of the population and is, in most cases, caused by the production of volatile sulfur compounds (VSCs), particularly methyl mercaptan and hydrogen sulfide, by specific bacterial species colonizing the oral cavity. In this study, a supercritical extract of Chinese licorice (Glycyrrhiza uralensis), and its major isoflavans, licoricidin and licorisoflavan A, were investigated for their effect on growth, VSC production and protease activity of Porphyromonas gingivalis, Prevotella intermedia and Solobacterium moorei, which have been associated with halitosis. The effects of licorice extract, licoricidin, and licorisoflavan A on VSC production in a saliva model were also tested. We first showed that licoricidin and licorisoflavan A, and to a lesser extent the licorice extract, were effective in inhibiting the growth of all three bacterial species, with minimal inhibitory concentrations in the range of 2-80 µg ml(-1). The licorice extract and the two isolates licoricidin and licorisoflavan A, were able to dose-dependently reduce VSC production by P. gingivalis, Prev. intermedia, and S. moorei as well as by a human saliva model. Although the extract and isolates did not inhibit the proteolytic activity of bacteria, they blocked the conversion of cysteine into hydrogen sulfide by Prev. intermedia. Lastly, the deodorizing effects of the licorice extract, licoricidin, and licorisoflavan A were demonstrated, as they can neutralize P. gingivalis-derived VSCs. Licorisoflavan A (10 µg ml(-1)) was found to be the most effective by reducing VSC levels by 50%. Within the limitations of this study, it can be concluded that a licorice supercritical extract and its major isoflavans (licoricidin and licorisoflavan A) represent natural ingredients with a potential for reducing bacterial VSC production and therefore for controlling halitosis.


Assuntos
Benzopiranos/uso terapêutico , Halitose/tratamento farmacológico , Saliva/microbiologia , Compostos de Enxofre/análise , Benzopiranos/isolamento & purificação , Benzopiranos/farmacologia , Glycyrrhiza/química , Halitose/microbiologia , Humanos , Boca/microbiologia
6.
J Nat Prod ; 74(12): 2514-9, 2011 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-22074222

RESUMO

Phytochemical investigation of a supercritical fluid extract of Glycyrrhiza uralensis has led to the isolation of 20 known isoflavonoids and coumarins, and glycycarpan (7), a new pterocarpan. The presence of two isoflavan-quinones, licoriquinone A (8) and licoriquinone B (9), in a fraction subjected to gel filtration on Sephadex LH-20 is due to suspected metal-catalyzed oxidative degradation of licoricidin (1) and licorisoflavan A (2). The major compounds in the extract, as well as 8, were evaluated for their ability to inhibit the growth of several major oral pathogens. Compounds 1 and 2 showed the most potent antibacterial activities, causing a marked growth inhibition of the cariogenic species Streptococcus mutans and Streptococcus sobrinus at 10 µg/mL and the periodontopathogenic species Porphyromonas gingivalis (at 5 µg/mL) and Prevotella intermedia (at 5 µg/mL for 1 and 2.5 µg/mL for 2). Only 1 moderately inhibited growth of Fusobacterium nucleatum at the highest concentration tested (10 µg/mL).


Assuntos
Antibacterianos , Cumarínicos , Isoflavonas , Pterocarpanos/isolamento & purificação , Quinonas , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Benzopiranos/química , Benzopiranos/metabolismo , Benzopiranos/farmacologia , Cumarínicos/química , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Relação Dose-Resposta a Droga , Fusobacterium nucleatum/efeitos dos fármacos , Alemanha , Glycyrrhiza uralensis , Humanos , Isoflavonas/química , Isoflavonas/isolamento & purificação , Isoflavonas/farmacologia , Testes de Sensibilidade Microbiana , Porphyromonas gingivalis/efeitos dos fármacos , Pterocarpanos/química , Pterocarpanos/farmacologia , Quinonas/química , Quinonas/isolamento & purificação , Quinonas/metabolismo , Quinonas/farmacologia , Streptococcus mutans/efeitos dos fármacos , Streptococcus sobrinus/efeitos dos fármacos
7.
J Periodontol ; 82(1): 122-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20722535

RESUMO

BACKGROUND: Inflammatory cytokines and matrix metalloproteinases (MMPs) produced by resident and inflammatory cells in response to periodontopathogens play a major role in the tissue destruction observed in periodontitis, which is a disease that affects tooth-supporting structures. In the present study, we investigate the effects of licorice-derived licoricidin (LC) and licorisoflavan A (LIA) on the secretion of various cytokines and MMPs by human monocyte-derived macrophages stimulated with Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) lipopolysaccharide (LPS). METHODS: Macrophages were treated with non-toxic concentrations of LC or LIA before being stimulated with A. actinomycetemcomitans LPS. The secretion of cytokines and MMPs and the activation of nuclear factor-kappa B (NF-κB) p65 and activator protein (AP)-1 were assessed by enzyme-linked immunosorbent assays. RESULTS: LC and LIA inhibited the secretion of interleukin (IL)-6 and chemokine (C-C motif) ligand 5 in a concentration-dependent manner but did not affect the secretion of IL-8 by LPS-stimulated macrophages. LC and LIA also inhibited the secretion of MMP-7, -8, and -9 by macrophages. The suppression of cytokine and MMP secretion by LC and LIA was associated with the reduced activation of NF-κB p65 but not that of AP-1. CONCLUSION: The present study suggests that LC and LIA have potential for the development of novel host-modulating strategies for the treatment of cytokine and/or MMP-mediated disorders such as periodontitis.


Assuntos
Benzopiranos/farmacologia , Citocinas/efeitos dos fármacos , Flavonoides/farmacologia , Glycyrrhiza , Macrófagos/efeitos dos fármacos , Metaloproteinases da Matriz/efeitos dos fármacos , Extratos Vegetais/farmacologia , Aggregatibacter actinomycetemcomitans , Linhagem Celular Tumoral , Quimiocina CCL5/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Humanos , Mediadores da Inflamação/imunologia , Interleucina-6/antagonistas & inibidores , Interleucina-8/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Macrófagos/enzimologia , Macrófagos/imunologia , Metaloproteinase 7 da Matriz , Metaloproteinase 8 da Matriz , Inibidores de Metaloproteinases de Matriz , Fator de Transcrição AP-1/efeitos dos fármacos , Fator de Transcrição RelA/efeitos dos fármacos
8.
J Periodontol ; 80(11): 1875-82, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19905958

RESUMO

BACKGROUND: Matrix metalloproteinases (MMPs) produced by resident and inflammatory cells in response to Gram-negative periodontopathogens play a major role in the tissue destruction observed during periodontitis, a disease that affects tooth-supporting structures. In this study, we investigated the effect of grape seed extract (GSE) on MMP secretion by human monocyte-derived macrophages stimulated with Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) lipopolysaccharide (LPS) and on the activity of human recombinant MMP-1 and -9. METHODS: Macrophages were treated with various concentrations of GSE prior to being stimulated with A. actinomycetemcomitans LPS. The secretion of MMPs and activation of nuclear factor-kappa B (NF-kappaB) p65 and activator protein-1 (AP-1) were assessed by enzyme-linked immunosorbent assay (ELISA). The effect of GSE on the catalytic activity of human recombinant MMP-1 and -9 was tested using fluorogenic assays. RESULTS: GSE inhibited the secretion of MMP-1, -3, -7, -8, -9, and -13 by LPS-stimulated macrophages in a concentration-dependent manner. The suppression of MMP secretion was associated with inhibition of NF-kappaB p65 and AP-1 activation. Also, GSE dose-dependently inhibited the activity of MMP-1 and -9. CONCLUSION: The present study suggests that GSE may be potentially used in the development of novel host-modulating strategies for the treatment of MMP-mediated disorders such as periodontitis.


Assuntos
Aggregatibacter actinomycetemcomitans/fisiologia , Antioxidantes/farmacologia , Extrato de Sementes de Uva/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Inibidores de Metaloproteinases de Matriz , Células Cultivadas , Humanos , Macrófagos/enzimologia , Metaloproteinase 1 da Matriz , Metaloproteinase 13 da Matriz , Metaloproteinase 3 da Matriz , Metaloproteinase 7 da Matriz , Metaloproteinase 8 da Matriz , Metaloproteinases da Matriz/metabolismo , NF-kappa B/efeitos dos fármacos , Proteínas Recombinantes , Fatores de Tempo , Fator de Transcrição AP-1/antagonistas & inibidores , Fator de Transcrição RelA/antagonistas & inibidores
9.
J Cosmet Dermatol ; 8(3): 197-204, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19735518

RESUMO

BACKGROUND: There is little scientific evidence to support the efficacy of natural deodorants and therefore, such products may be perceived as inefficacious. The evaluation of the in vitro antibacterial activity of a hop extract and the evaluation of the odor-reducing capacity of a hops/zinc ricinoleate-containing product by a sensory evaluation panel is employed to verify deodorant performance. AIMS: The goal of this study was to evaluate the in vitro antibacterial activity of a hop extract against Corynebacterium xerosis and Staphylococcus epidermidis and to verify in vivo deodorant performance of a hops/zinc ricinoleate-containing product. METHODS: The hops extract was evaluated on a culture of an armpit swab from six volunteers. Furthermore, the extract was submitted to a zone of inhibition test and an agar-dilution assay against two major odor-causing bacteria. The clinical evaluation of the finished product was carried out according to a standard method for substantiating deodorant efficacy using trained odor judges for the assessment of axillary malodor (ASTM method E 1207-87 Standard Practice for the Sensory Evaluation of Axillary Deodorancy). RESULTS: The supercritical hops extract showed good antibacterial activities in all three tests. Minimum inhibitory concentration values of 6.25 and 25 mug/mL against C. xerosis and S. aureus, respectively, were obtained in the agar-dilution assay. In the clinical underarm odor-reduction evaluation, the mean malodor score dropped from 6.28 (+/-0.70) to 1.80 (+/-0.71) after 8 h of application. There was still a noticeable effect at both 12 and 24 h after the application, with a score of 1.82 (+/-0.74) and 2.24 (+/-0.77), respectively. CONCLUSION: The hops extract has good in vitro antibacterial properties and, in combination with zinc ricinoleate in an appropriate base, delivers in vivo odor reduction. The clinical efficacy is likely due to a combination of the base ingredients and the antibacterial actives.


Assuntos
Antibacterianos/farmacologia , Corynebacterium/efeitos dos fármacos , Desodorantes/farmacologia , Humulus , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Ácidos Ricinoleicos/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cicloexanonas/farmacologia , Cicloexenos/farmacologia , Humanos , Odorantes/prevenção & controle , Extratos Vegetais/isolamento & purificação , Staphylococcus aureus/efeitos dos fármacos , Terpenos/farmacologia , Triclosan/farmacologia
10.
J Periodontol ; 79(9): 1752-61, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18771378

RESUMO

BACKGROUND: Periodontal diseases are a group of inflammatory disorders initiated by specific Gram-negative periodontopathogenic bacteria that lead to the destruction of tooth-supporting tissues. In this study, we tested whether a carbon dioxide-supercritical extract of Glycyrrhiza uralensis (licorice) can reduce the periodontopathogen-induced inflammatory response. METHODS: Monocyte-derived macrophages were treated with various concentrations of the licorice extract prior to being stimulated with Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) and Porphyromonas gingivalis lipopolysaccharide (LPS). The capacity of the licorice extract to mediate the inflammatory response was also tested in an ex vivo whole blood model stimulated with P. gingivalis LPS. The secretion of interleukin (IL)-1beta, -6, and -8 and tumor necrosis factor-alpha (TNF-alpha) in both models was assessed by enzyme-linked immunosorbent assays. Changes in the phosphorylation state of macrophage intracellular kinases induced by A. actinomycetemcomitans LPS and the licorice extract in the macrophage model were characterized by immunoblotting. RESULTS: The licorice extract exhibited potent anti-inflammatory properties, inhibiting the periodontopathogen LPS-induced IL-1beta, -6, and -8 and TNF-alpha responses of macrophages. The licorice extract inhibited the phosphorylation of important macrophage intracellular signaling proteins, including nuclear factor-kappa B p65 nuclear transcription factor and Jun proto-oncogene-encoded activator protein (AP) 1 transcription factor, which are involved in inflammatory signaling pathways. The licorice extract was also a potent inhibitor of the proinflammatory cytokine response in the ex vivo human whole blood model. CONCLUSION: This CO(2)-supercritical licorice extract is a potential candidate for the development of a new therapy to prevent and/or treat periodontitis-associated tissue destruction.


Assuntos
Anti-Inflamatórios/farmacologia , Citocinas/efeitos dos fármacos , Glycyrrhiza , Mediadores da Inflamação/análise , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Aggregatibacter actinomycetemcomitans , Citocinas/sangue , Humanos , Immunoblotting , Interleucina-1beta/sangue , Interleucina-1beta/efeitos dos fármacos , Interleucina-6/análise , Interleucina-6/sangue , Interleucina-8/sangue , Interleucina-8/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Lipopolissacarídeos/antagonistas & inibidores , Macrófagos/enzimologia , Proteína Quinase 7 Ativada por Mitógeno/efeitos dos fármacos , Doenças Periodontais/sangue , Doenças Periodontais/microbiologia , Fosforilação , Porphyromonas gingivalis , Proto-Oncogene Mas , Fator de Transcrição AP-1/efeitos dos fármacos , Fator de Transcrição RelA/efeitos dos fármacos , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/efeitos dos fármacos
11.
J Nat Prod ; 69(3): 432-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16562853

RESUMO

A 70% ethanol extract of California poppy (Eschscholzia californica) was able to bind to 5-HT(1A) and 5-HT(7) receptors at 100 mug/mL. The subsequent isolation procedure yielded the known alkaloids californidine (1), escholtzine (2), N-methyllaurotetanine (3), caryachine (4), and O-methylcaryachine (5), along with a new pavine alkaloid, 6S,12S-neocaryachine-7-O-methyl ether N-metho salt (7). The structure of 7 was determined by spectroscopic data interpretation, while the absolute stereochemistry was determined by means of circular dichroism. From the results obtained from the radioligand-binding assay of the pure compounds, including the commercially available protopine (6), it was evident that the activity on the 5-HT(1A) receptor was at least partly due to the presence of the aporphine alkaloid 3, which showed the highest inhibition of [(3)H]8-hydroxy-2-(di-N-propylamino)tetralin ([(3)H]8-OH-DPAT) binding with an EC(50) value of 155 nM and a K(i) of 85 nM.


Assuntos
8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Alcaloides , Eschscholzia/química , Receptor 5-HT1A de Serotonina/efeitos dos fármacos , Agonistas do Receptor de Serotonina/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Benzilisoquinolinas/química , Benzilisoquinolinas/isolamento & purificação , Benzilisoquinolinas/farmacologia , Dioxóis/química , Dioxóis/isolamento & purificação , Dioxóis/farmacologia , Humanos , Estrutura Molecular
12.
J Agric Food Chem ; 53(8): 3076-80, 2005 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-15826062

RESUMO

The aqueous extract of American skullcap (Scutellaria lateriflora L. (S. lateriflora), Lamiaceae) has been traditionally used by North American Indians as a nerve tonic and for its sedative and diuretic properties. Recent reports stated that flavonoids and possibly amino acids are responsible for the anxiolytic activity. As a part of our search for environmentally friendly solvents to extract the active components from medicinal plants, we used S. lateriflora in a comparison of accelerated solvent extraction (ASE) using water, and supercritical fluid extraction (SFE) using CO2 and 10% EtOH as modifier, at different temperatures. Flavonoids and amino acids were quantified by HPLC-UV and HPLC-MS, respectively. The flavonoid content was compared with conventional extraction methods (hot water extraction and 70% ethanol). The use of ASE at 85 degrees C with water as solvent gave the best results for flavonoid glycosides and amino acids, whereas SFE gave higher yields of flavonoid aglycones. However, the results obtained for total flavonoids were not significatively superior to hot water extraction or 70% aqueous EtOH extract.


Assuntos
Cromatografia com Fluido Supercrítico , Etanol , Extratos Vegetais/química , Scutellaria/química , Água , Aminoácidos/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Solventes
13.
J Agric Food Chem ; 52(6): 1546-50, 2004 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-15030209

RESUMO

Despite the wide availability of liquid herbal extracts using mixtures of alcohol, glycerin, and water, or glycerin and water as solvents, no data on the chemical composition of such extracts is readily available. In this study, the amount and the stability of the major saponins in Panax quinquefolius root extracts, made either with 50% (v/v) aqueous ethanol, a mixture (v/v/v) of 20% ethanol, 40% glycerin, and 40% water, or with 65% (v/v) aqueous glycerin, were evaluated by HPLC-UV analysis. The amount of total saponins was highest in the 50% aqueous ethanol extract (61.7 +/- 0.1 mg/g dry root), although similar to the ethanol-glycerin-water extract (59.4 +/- 0.5 mg/g dry root). Saponins were significantly lower in the 65% aqueous glycerin extract (51.5 +/- 0.2 mg/g dry root). Interestingly, the amounts of individual saponins were quite variable depending on the solvent. This is in part due to enzymatic cleavage of ginsenosides in the glycerin containing extracts during the maceration process. Storage of the extracts at 25 degrees C over the period of a year led to a 13-15% loss of saponins with all three types of extractions.


Assuntos
Cromatografia Líquida de Alta Pressão , Panax/química , Raízes de Plantas/química , Saponinas/isolamento & purificação , Etanol , Glicerol , Extratos Vegetais/química , Solventes , Água
14.
J AOAC Int ; 86(3): 453-60, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12852558

RESUMO

Methods using liquid chromatography with UV detection (LC-UV), thin-layer chromatography (TLC), and digital photomicroscopy were developed to distinguish between the different species of Scutellaria lateriflora L. and its adulterants Teucrium canadense L. and T. chamaedrys L. Chemically, the 70% ethanol extract of S. lateriflora is characterized by the presence of flavonoids--predominantly baicalin, lateriflorin, dihydrobaicalin, and baicalein. The major compounds of the 70% ethanol extract of T. canadense are phenylpropanoids, with verbascoside as the most prominent, and a variable amount of teucrioside. Teucrioside is the major compound in T. chamaedrys, but it is not present in S. lateriflora. The presence of phenylpropane glycosides can therefore be used to distinguish between the S. lateriflora L. and the two Teucrium species by LC-UV and TLC. The abundant strap-shaped trichomes on the stem, as well as bristle-like trichomes on the leaf, are typically seen microscopically for T. canadense, whereas the waxy cuticle with numerous glandular scales is found in T. chamaedrys. These cell structures were used to determine the adulteration of S. lateriflora crude herb with either of the two Teucrium species.


Assuntos
Scutellaria/química , Teucrium/química , Cromatografia Líquida , Cromatografia em Camada Fina , Microscopia , Extratos Vegetais/análise , Scutellaria/citologia , Teucrium/citologia
15.
J Nat Prod ; 66(4): 535-7, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12713409

RESUMO

The hot water and 70% ethanol extracts of dried mad-dog skullcap (Scutellaria lateriflora) both bound to the 5-HT(7) receptor, with 87.2 +/- 6.2% and 56.7 +/- 1.3% inhibition of [(3)H]-LSD binding to the receptor at 100 microg/mL, respectively. The on-line analysis of a 70% ethanol extract by HPLC-UV/MS resulted in the identification of five flavones (1-5). Fractionation of the ethanol extract resulted in the isolation of three flavone-glucuronides (6-8) and a flavanone-glucuronide (9), including one new compound, lateriflorin (5,6,-dihydroxy-7-glucuronyloxy-2'-methoxyflavone) (8). The structure of 8 was determined by NMR ((1)H NMR, (13)C NMR, and NOESY experiments) and MS analysis. From the results obtained in the testing of the pure compounds, it is evident that the activity on the 5-HT(7) receptor is at least partly due to the presence of flavonoids. Scutellarin and ikonnikoside I showed the highest inhibition of [(3)H]-LSD binding with IC(50) values of 63.4 and 135.1 microM, respectively.


Assuntos
Flavonoides/isolamento & purificação , Plantas Medicinais/química , Receptores de Serotonina/efeitos dos fármacos , Scutellaria/química , Antagonistas da Serotonina/isolamento & purificação , Células Cultivadas/efeitos dos fármacos , Flavonas , Flavonoides/química , Flavonoides/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Antagonistas da Serotonina/química , Antagonistas da Serotonina/farmacologia , Vermont
16.
J Agric Food Chem ; 50(14): 3967-70, 2002 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-12083867

RESUMO

Recent work has shown that enzymatic degradation and oxidation of cichoric acid and other caffeic derivatives occurs in Echinacea preparations. However, very little is known as to the means of stabilizing these phytopreparations. To stabilize the glycerin extract of Echinacea purpurea, we have evaluated the effects of 3 natural antioxidants (citric acid, malic acid, and hibiscus extract) on the stability of the major caffeic acid derivatives (caftaric acid, caffeic acid, cichoric acid, and 2-O-feruloyl-tartaric acid). Chlorogenic acid, which normally occurs in an ethanol extract of E. purpurea, was not present in the glycerin extract. The caffeic acid derivatives, with the exception of 2-O-feruloyl-tartaric acid, were subject to degradation in the control sample. 2-O-Feruloyl-tartaric acid was stable during the whole testing period. All antioxidant treatments greatly improved the stability of caffeic acid derivatives. Stability was dependent upon the concentration of antioxidant added.


Assuntos
Antioxidantes/farmacologia , Ácidos Cafeicos/química , Ácido Clorogênico/análogos & derivados , Echinacea/química , Glicerol , Extratos Vegetais/química , Succinatos , Ácido Clorogênico/química , Cromatografia Líquida de Alta Pressão , Ácido Cítrico/farmacologia , Estabilidade de Medicamentos , Malatos/farmacologia , Malvaceae/química , Tartaratos/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...