Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Planta Med ; 82(4): 356-61, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26669677

RESUMO

A reversed-phase high-performance liquid chromatography method was developed for the chemical fingerprinting of Commiphora wightii gum resin (guggul). This method was also used for the quantification of E- and Z-guggulsterones in different C. wightii gum resin samples. The analysis was conducted on a high-performance liquid chromatography system with a reversed-phase column using a gradient elution comprised of water and acetonitrile with 0.1% acetic acid, and a run time of 50 min at 38 °C. The calibration curve of E- and Z-guggulsterones showed good linearity with a standard correlation coefficient >0.999, which is within the established range (0.5-250 µg/mL). Twelve marker compounds were selected and successfully analyzed by this method in 22 C. wightii gum resin samples along with 9 gum resin samples of possible adulterant species.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Commiphora/química , Pregnenodionas/análise , Resinas Vegetais/química
2.
J AOAC Int ; 98(3): 757-759, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26086254

RESUMO

The central nervous system stimulant 1,3-dimethylamylamine (DMAA) has been found in preworkout products and dietary supplements. A fast direct analysis in real time-quadrupole time of flight-MS method was used for identification of DMAA in dietary supplements and to determine if this compound is present in geranium (Pelargonium graveolens) plants or oil. This method involved the use of [M+H]+ ions in the positive mode based on the exact mass of DMAA. The results of this investigation showed that DMAA was not detected from authentic samples of P. graveolens plant material or pelargonium oil or in multiple samples of commercially available pelargonium oil. DMAA was detected in three samples of dietary supplements. The LOD of DMAA was found to be 10 ng/mL.


Assuntos
Aminas/análise , Suplementos Nutricionais/análise , Geranium/química , Limite de Detecção , Espectrometria de Massas , Óleos de Plantas/análise , Plantas/química , Reprodutibilidade dos Testes
3.
J Nat Med ; 68(4): 686-98, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24928704

RESUMO

The edible tubers from different species of Dioscorea are a major source of food and nutrition for millions of people. Some of the species are medicinally important but others are toxic. The genus consists of about 630 species of almost wholly dioecious plants, many of them poorly characterized. The taxonomy of Dioscorea is confusing and identification of the species is generally problematic. There are no adequate anatomical studies available for most of the species. This study is aimed to fill this gap and provides a detailed investigation of the anatomy and micro-morphology of the rhizomes and tubers of five different species of Dioscorea, namely D. balcanica, D. bulbifera, D. polystachya, D. rotundata and D. villosa. The primary features that can help in distinguishing the species include the nature of periderm, presence or absence of pericyclic sclereids, lignification in the phloem, types of calcium oxalate crystals and features of starch grains. The descriptions are supported with images of bright-field and scanning electron microscopy for better understanding of these species. The diagnostic key of anatomical features included in this paper can help distinguish the investigated species unambiguously. Additionally, HPTLC analyses of authentic and commercial samples of the five species are described.


Assuntos
Dioscorea/anatomia & histologia , Dioscorea/química , Cromatografia em Camada Fina , Dioscorea/classificação , Dioscorea/ultraestrutura , Tubérculos/anatomia & histologia , Tubérculos/química , Tubérculos/classificação , Tubérculos/ultraestrutura
4.
Planta Med ; 80(4): 321-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24510365

RESUMO

Yam (Dioscorea spp.) is an important edible tuber plant used for medicinal purposes to promote health and longevity in Chinese tradition. Steroidal saponins were reported to be the major physiologically active constituents in yams. In this current work, the structural characteristics of steroidal saponins in methanolic extracts from dried rhizomes of two Dioscorea species (D. villosa L. and D. cayenensis Lam.) and dietary supplements have been identified and analyzed using UHPLC/QTOF-MS in both negative and positive ion modes. The fragmentation patterns of reference standards were determined and the steroidal saponins in the extracts were identified or tentatively characterized from their retention times and mass spectra. The fragments produced by collision-induced dissociation (CID) revealed the characteristic cleavage of glycosidic bonds, and the fragmentation pattern provided structural information about the sugars. Twenty-one saponins, including four tentatively identified compounds, were detected in the crude extracts of two Dioscorea species. These saponins can be used to distinguish D. villosa from D. cayenensis. For example, asperin and gracillin are found only in D. cayenensis, and dioscoreavilloside A and B and parvifloside are only found in D. villosa. This can be used to determine the presence or absence of D. villosa in commercial products, which may help determine the spiking of plant material, and/or prevent the use of potentially mislabeled or misidentified "Dioscorea" material. The analytical method also provided an alternative, fast method for quality control of Dioscorea species in dietary supplements. Principal component analysis showed that Dioscorea species and commercial products were easily distinguished. From this a partial least squares model was constructed to determine what species are in different products.


Assuntos
Dioscorea/química , Contaminação de Medicamentos/prevenção & controle , Extratos Vegetais/química , Rizoma/química , Saponinas/análise , Esteroides/análise , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Dioscorea/classificação , Estrutura Molecular , Análise de Componente Principal , Padrões de Referência , Saponinas/química , Especificidade da Espécie , Espectrometria de Massas por Ionização por Electrospray/métodos , Esteroides/química
5.
J Nat Prod ; 77(3): 509-15, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24471493

RESUMO

Six new octulosonic acid derivatives (1-6) were isolated from the flower heads of Roman chamomile (Chamaemelum nobile). Their structures were elucidated by means of spectroscopic interpretation. The biological activity of the isolated compounds was evaluated toward multiple targets related to inflammation and metabolic disorder such as NAG-1, NF-κB, iNOS, ROS, PPARα, PPARγ, and LXR. Similar to the action of NSAIDs, all the six compounds (1-6) increased NAG-1 activity 2-3-fold. They also decreased cellular oxidative stress by inhibiting ROS generation. Compounds 3, 5, and 6 activated PPARγ 1.6-2.1-fold, while PPARα was activated 1.4-fold by compounds 5 and 6 only. None of the compounds showed significant activity against iNOS or NF-κB. This is the first report of biological activity of octulosonic acid derivatives toward multiple pathways related to inflammation and metabolic disorder. The reported anti-inflammatory, hypoglycemic, antiedemic, and antioxidant activities of Roman chamomile could be partly explained as due to the presence of these constituents.


Assuntos
Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Chamaemelum/química , Açúcares Ácidos/isolamento & purificação , Açúcares Ácidos/farmacologia , Anti-Inflamatórios não Esteroides/química , Flores/química , Hipoglicemiantes/farmacologia , Mississippi , Estrutura Molecular , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Ressonância Magnética Nuclear Biomolecular , Estresse Oxidativo/efeitos dos fármacos , PPAR alfa/metabolismo , PPAR gama/metabolismo , Açúcares Ácidos/química
6.
Neurotoxicol Teratol ; 41: 80-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24368316

RESUMO

The use of over-the-counter botanical estrogens containing isolated soy isoflavones, including genistein and daidzein, has become a popular alternative to traditional hormone therapies. Menopausal women use these products as an aide in healthy aging, including for the maintenance of cognitive function. The safety and efficacy of many of these commercial preparations remain unknown. Previous research in our lab found that treatment of ovariectomized (OVX) female Long-Evans rats with genistein impaired working memory in an operant delayed spatial alternation (DSA) task and response learning in a plus-maze, but enhanced place learning assessed in the plus-maze. The present study further examined the effects of isolated isoflavones on working memory and place learning by treating middle-aged (12-13 month old) OVX female Long-Evans rats with S-equol, the exclusive enantiomer produced by metabolism of daidzein in the mammalian gut. S-equol binds selectively to ERß with an affinity similar to that of genistein but has low transcriptional potency. For DSA testing, S-equol at 1.94, 0.97 mg, or 0mg (sucrose control) was orally administered to animals daily, 30 min before behavioral testing, and again both 4 and 8 hours after the first treatment. Rats were tested on the DSA task following the first, morning dose. For place learning, rats received 0.97 mg S-equol every 4 hours during the light portion of the cycle beginning 48 hours prior to behavioral testing (total exposure 8.7 mg S-equol). S-equol treatment was largely without effect on the DSA and place learning tasks. This is the first study to test the behavioral effects of isolated S-equol in OVX rodents, and shows that, unlike genistein or estradiol, repeated daily treatment with this isoflavone metabolite does not alter learning and memory processes in middle-aged OVX rats.


Assuntos
Equol/administração & dosagem , Transtornos da Memória/dietoterapia , Análise de Variância , Animais , Condicionamento Operante/efeitos dos fármacos , Relação Dose-Resposta a Droga , Equol/sangue , Feminino , Genisteína/toxicidade , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/induzido quimicamente , Memória de Curto Prazo , Ovariectomia , Fitoestrógenos/toxicidade , Ratos , Ratos Long-Evans , Proteínas de Soja/administração & dosagem
7.
Biomed Chromatogr ; 28(2): 281-94, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24019066

RESUMO

Ultra high-performance liquid chromatography (UHPLC) with evaporative light scattering detection was used for the quantification of steroidal saponins and diosgenin from the rhizomes or tubers of various Dioscorea species and dietary supplements that were purported to contain Dioscorea. The analysis was performed on an Acquity UPLC™ system with an UPLC™ BEH Shield RP18 column using a gradient elution with water and acetonitrile. Owing to their low UV absorption, the steroidal saponins were observed by evaporative light scattering detection. The 12 compounds could be separated within 15 min using the developed UHPLC method with detection limits of 5-12 µg/mL with 2 µL injection volume. The analytical method was validated for linearity, repeatability, accuracy, limits of detection and limits of quantification. The relative standard deviations for intra- and inter-day experiments were <3.1%, and the recovery efficiency was 97-101%. The total content of standard compounds was found to be in the ranges 0.01-14.5% and 0.9-28.6 mg daily intake for dry plant materials and solid commercial preparations, respectively. UHPLC-mass spectrometry with a quadrupole mass analyzer and ESI source was used only for confirmation of the identity of the various saponins. The developed method is simple, rapid and especially suitable for quality control analysis of commercial products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Dioscorea/química , Diosgenina/análise , Extratos Vegetais/química , Saponinas/análise , Diosgenina/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Saponinas/química
8.
J Pharm Biomed Anal ; 88: 278-88, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24095803

RESUMO

A new rapid UHPLC-UV-QTOF/MS method has been developed for the simultaneous analysis of nine phenolic compounds [(Z)-2-ß-d-glucopyranosyloxy-4-methoxycinnamic acid (cis-GMCA), chlorogenic acid, (E)-2-ß-d-glucopyranosyloxy-4-methoxycinnamic acid (trans-GMCA), quercetagetin-7-O-ß-d-glucopyranoside, luteolin-7-O-ß-d-glucoside, apigenin-7-O-ß-d-glucoside, chamaemeloside, apigenin 7-O-(6″-O-acetyl-ß-d-glucopyranoside), apigenin] and one polyacetylene (tonghaosu) from the flower heads of Chamomile/Chrysanthemum samples. The chromatographic separation was achieved using a reversed phase C18 column with a mobile phase of water and acetonitrile, both containing 0.05% formic acid. The ten compounds were completely separated within 15min at a flow rate of 0.25mL/min with a 2µL injection volume. The different chemo-types of Chamomiles/Chrysanthemum displayed variations in the presence of chemical constituents. German Chamomile samples confirmed the presence of cis-GMCA, trans-GMCA, apigenin-7-O-ß-d-glucoside and tonghaosu as major constituents whereas Roman chamomile samples confirmed the presence of chamamaeloside and apigenin as major compounds. The Chrysanthemum morifolium samples showed the presence of luteolin-7-O-ß-d-glucose as the major compound. The method was applied for the analysis of various commercial products including capsules, tea bags, body and hair care products. LC-mass spectrometry with electrospray ionization (ESI) interface method is described for the evaluation of ten compounds in plant samples and commercial products. This method involved the detection of [M+Na](+) and [M+H](+) ions in the positive mode. Partial least squares discriminant analysis (PLS-DA) was used to visualize commercial samples quality and may be of value for discriminating between chamomile types and Chrysanthemum with regards to the relative content of individual constituents. The results indicated that the method is suitable as a quality control test for various Chamomile/Chrysanthemum samples and market products.


Assuntos
Camomila/química , Chrysanthemum/química , Flores/química , Calibragem , Química Farmacêutica , Cromatografia Líquida de Alta Pressão , Íons , Análise dos Mínimos Quadrados , Espectrometria de Massas , Fenol/química , Extratos Vegetais/química , Análise de Componente Principal , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta
9.
Planta Med ; 79(15): 1421-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23970424

RESUMO

Dioscorea villosa (wild yam) is native to North America and has been widely used as a natural alternative for estrogen replacement therapy to improve women's health as well as to treat inflammation, muscle spasm, and asthma. Diosgenin and dioscin (glycoside form of diosgenin) are reported to be the pharmacologically active compounds. Despite the reports of significant pharmacological properties of dioscin and diosgenin in conditions related to inflammation, cancer, diabetes, and gastrointestinal ailments, no reports are available on ADME properties of these compounds. This study was carried out to determine ADME properties of diosgenin and dioscin and their effects on major drug metabolizing enzymes (CYP 3A4, 2D6, 2C9, and 1A2). The stability was determined in simulated gastric and intestinal fluids (SGF, pH 1.2 and SIF, pH 6.8), and intestinal transport was evaluated in Caco-2 model. Phase I and phase II metabolic stability was determined in human liver microsomes and S9 fractions, respectively. Quantitative analysis of dioscin and diosgenin was performed by UPLC-MS system. Dioscin degraded up to 28.3 % in SGF and 12.4 % in SIF, which could be accounted for by its conversion to diosgenin (24.2 %. in SGF and 2.4 % in SIF). The depletion of diosgenin in SGF and SIF was < 10 %. Diosgenin was stable in HLM but disappeared in S9 fraction with a half-life of 11.3 min. In contrast, dioscin was stable in both HLM and S9 fractions. Dioscin showed higher permeability across Caco-2 monolayer with no significant efflux, while diosgenin was subjected to efflux mediated by P-glycoprotein. Diosgenin and dioscin inhibited CYP3A4 with IC50 values of 17 and 33 µM, respectively, while other CYP enzymes were not affected. In conclusion, dioscin showed better intestinal permeability. Conversion of dioscin to diosgenin was observed in both gastric and intestinal fluids. No phase I metabolism was detected for both compounds. The disappearance of diosgenin in S9 fraction indicated phase II metabolism.


Assuntos
Dioscorea/química , Diosgenina/farmacocinética , Desintoxicação Metabólica Fase II , Extratos Vegetais/farmacocinética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Anti-Inflamatórios/farmacocinética , Células CACO-2 , Citocromo P-450 CYP3A/metabolismo , Diosgenina/análogos & derivados , Diosgenina/metabolismo , Meia-Vida , Humanos , Concentração Inibidora 50 , Absorção Intestinal , Parassimpatolíticos/farmacocinética , Permeabilidade , Extratos Vegetais/metabolismo
10.
Planta Med ; 79(12): 1084-95, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23877921

RESUMO

Medicinal plants are a rich source of ligands for nuclear receptors. The present study was aimed to screen a collection of plant extracts for PPARα/γ-activating properties and identify the active extract that can stimulate cellular glucose uptake without enhancing the adipogenesis. A reporter gene assay was performed to screen ethanolic extracts of 263 plant species, belonging to 94 families, for activation of PPARα and PPARγ. Eight extracts showed activation of PPARγ, while 22 extracts showed activation of PPARα. The extracts of five plants (Daphne gnidium, Illicium anisatum, Juniperus virginiana, Terminalia chebula, and Thymelaea hirsuta) showed activation of both PPARα and PPARγ and out of them, D. gnidium and T. hirsuta markedly increased PPARα/γ protein expression. All five extracts showed an increase in cellular glucose uptake. Of the five dual agonists, T. chebula and T. hirsuta did not show any increase in differentiation of 3T3-L1 preadipocytes, but I. anisatum caused an increase in adipogenesis, while D. gnidium and J. virginiana were toxic to adipocytes. The adipogenic effect of rosiglitazone was antagonized by T. chebula and T. hirsuta. It was concluded that T. hirsuta and T. chebula retain the property of elevating glucose uptake as PPARα/γ dual agonists without the undesired side effect of adipogenesis. This is the first report to reveal the PPARα/γ dual agonistic action and glucose uptake enhancing property of T. hirsuta and T. chebula.


Assuntos
Adipogenia/efeitos dos fármacos , Glucose/metabolismo , PPAR alfa/efeitos dos fármacos , PPAR gama/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Genes Reporter , Células Hep G2 , Humanos , Camundongos , PPAR alfa/agonistas , PPAR alfa/metabolismo , PPAR gama/agonistas , PPAR gama/metabolismo , Componentes Aéreos da Planta/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Rosiglitazona , Tiazolidinedionas/farmacologia
11.
FASEB J ; 27(11): 4406-18, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23882126

RESUMO

Because little is known about the actions of botanical estrogens (BEs), widely consumed by menopausal women, we investigated the mechanistic and cellular activities of some major BEs. We examined the interactions of genistein, daidzein, equol, and liquiritigenin with estrogen receptors ERα and ERß, with key coregulators (SRC3 and RIP140) and chromatin binding sites, and the regulation of gene expression and proliferation in MCF-7 breast cancer cells containing ERα and/or ERß. Unlike the endogenous estrogen, estradiol (E2), BEs preferentially bind to ERß, but their ERß-potency selectivity in gene stimulation (340- to 830-fold vs. E2) is enhanced at several levels (coregulator recruitment, chromatin binding); nevertheless, at high (0.1 or 1 µM) concentrations, BEs also fully activate ERα. Because ERα drives breast cancer cell proliferation and ERß dampens this, the relative levels of these two ERs in target cells and the BE dose greatly affect gene expression and proliferative response and will be crucial determinants of the potential benefits vs. risks of BEs. Our findings reveal key and novel mechanistic differences in the estrogenic activities of BEs vs. E2, with BEs displaying patterns of activity distinctly different from those seen with E2 and provide valuable information to inform future studies.


Assuntos
Receptor beta de Estrogênio/metabolismo , Fitoestrógenos/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sítios de Ligação , Proliferação de Células , Cromatina/metabolismo , Relação Dose-Resposta a Droga , Estradiol/farmacologia , Receptor alfa de Estrogênio/metabolismo , Humanos , Células MCF-7 , Proteínas Nucleares/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Proteína 1 de Interação com Receptor Nuclear , Transcrição Gênica
12.
Nat Prod Commun ; 8(3): 319-21, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23678800

RESUMO

Nine glycosides of spirostan (1-7) and furostan (8 and 9) type steroids including a new compound, 7-oxodioscin (1), were isolated from the rhizomes of Dioscorea nipponica. The structure of 1 was established as (25R)-3beta-O-[(alpha-L-rhamnopyranosyl-(1 --> 4)-O-[alpha-L-rhamnopyranosyl-(1 --> 2)]-beta-D-glucopyranosyl)oxy]spirost-5-en-7-one by extensive spectroscopic techniques including HRESI-TOFMS, 1D and 2D NMR, and chemical methods. Known compounds were elucidated as dioseptemloside G (2), (25R)-dracaenoside G (3), orbiculatoside B (4), dioscin (5), progenin III (6), gracillin (7), (3beta3,22alpha,25R)-26-(beta-D-glucopyranosyloxy)-22-methoxyfurost-5-en-3-yl O-[alpha-L-rhamnopyranosyl-(1 --4)]-beta-D-glucopyranoside (8), and methylprotodioscin (9).


Assuntos
Dioscorea/química , Glicosídeos/química , Espirostanos/química , Estrutura Molecular , Esteroides/química
13.
Nat Prod Commun ; 8(3): 323-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23678801

RESUMO

Two new fatty acid-spirostan steroid glycoside esters, progenin III palmitate (1) and progenin III linoleate (2), were isolated from the MeOH extract of Dioscorea cayenensis rhizomes. The extract also yielded seven previously known spirostan and furostan steroid glycosides (3-9). The structures of the new compounds were established as (25R)-spirost-5-en-3beta-yl O-alpha-L-rhamnopyranosyl-(1 --> 2)-[6-O-palmitoyl]-O-beta-D-glucopyranoside (1) and (25R)-spirost-5-en-3beta-yl O-alpha-L-rhamnopyranosyl-(1 --> 2)-[6-O-linoleoyl]-O-beta-D-glucopyranoside (2) by chemical and spectroscopic methods, including 1D and 2D NMR. The known compounds were identified as progenin III (3), dioscin (4), deltonin (5), asperin (6), gracillin (7), protodioscin (8)], and methyl protodioscin (9).


Assuntos
Dioscorea/química , Glicosídeos/química , Espirostanos/química , Diosgenina/análogos & derivados , Diosgenina/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Saponinas/química
14.
J Biol Chem ; 288(5): 3163-73, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23243312

RESUMO

Valerian is an herbal preparation from the roots of Valeriana officinalis used as an anxiolytic and sedative and in the treatment of insomnia. The biological activities of valerian are attributed to valerenic acid and its putative biosynthetic precursor valerenadiene, sesquiterpenes, found in V. officinalis roots. These sesquiterpenes retain an isobutenyl side chain whose origin has been long recognized as enigmatic because a chemical rationalization for their biosynthesis has not been obvious. Using recently developed metabolomic and transcriptomic resources, we identified seven V. officinalis terpene synthase genes (VoTPSs), two that were functionally characterized as monoterpene synthases and three that preferred farnesyl diphosphate, the substrate for sesquiterpene synthases. The reaction products for two of the sesquiterpene synthases exhibiting root-specific expression were characterized by a combination of GC-MS and NMR in comparison to the terpenes accumulating in planta. VoTPS7 encodes for a synthase that biosynthesizes predominately germacrene C, whereas VoTPS1 catalyzes the conversion of farnesyl diphosphate to valerena-1,10-diene. Using a yeast expression system, specific labeled [(13)C]acetate, and NMR, we investigated the catalytic mechanism for VoTPS1 and provide evidence for the involvement of a caryophyllenyl carbocation, a cyclobutyl intermediate, in the biosynthesis of valerena-1,10-diene. We suggest a similar mechanism for the biosynthesis of several other biologically related isobutenyl-containing sesquiterpenes.


Assuntos
Alquil e Aril Transferases/metabolismo , Biocatálise , Vias Biossintéticas , Sesquiterpenos/metabolismo , Valeriana/enzimologia , Vias Biossintéticas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Hidrocarbonetos/metabolismo , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sesquiterpenos/química , Especificidade por Substrato , Valeriana/genética
15.
Nat Prod Commun ; 7(9): 1177-80, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23074901

RESUMO

A rapid UPLC method was developed for the simultaneous analysis of five indole alkaloids (harmalol, harmol, harmane, harmaline and harmine) and four flavonoids (orientin, isoorientin, vitexin, and isovitexin) from the aerial parts of Passiflora incarnata L. (Passifloraceae), other species of Passiflora (P. violacea Veil., P. edulis Sims., P. suberosa L., P. morifolia Mast. and P. quadrangularis L.), Peganum harmala, and dietary supplements that claim to contain Passiflora. The separation was achieved within eight minutes by using C-18 column, a water/acetonitrile mobile phase, both containing formic acid, using a gradient system and a temperature of 35 degrees C. The method was validated for linearity, repeatability, limits of detection (LOD), and limits of quantification (LOQ). The wavelength used for quantification with the diode array detector was 340 nm for flavonoids and alkaloids. The developed method is simple, economic, fast and especially suitable for quality control analysis of flavonoids and alkaloids in plant samples and dietary supplements. The compounds (including isoschaftoside and schaftoside) in plant samples and commercial products of Passiflora were identified and confirmed by UPLC-MS. A HPTLC method was also developed for the chemical fingerprint analysis of Passiflora samples.


Assuntos
Alcaloides/análise , Flavonoides/análise , Passiflora/química , Cromatografia Líquida , Cromatografia em Camada Fina , Suplementos Nutricionais , Espectrometria de Massas , Controle de Qualidade , Espectrofotometria Ultravioleta
16.
J Nat Prod ; 75(9): 1665-73, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-22938174

RESUMO

Natural products have provided a basis for health care and medicine to humankind since the beginning of civilization. According to the World Health Organization (WHO), approximately 80% of the world population still relies on herbal medicines for health-related benefits. In the United States, over 42% of the population claimed to have used botanical dietary supplements to either augment their current diet or to "treat" or "prevent" a particular health-related issue. This has led to the development of a burgeoning industry in the U.S. ($4.8 billion per year in 2008) to supply dietary supplements to the consumer. However, many commercial botanical products are poorly defined scientifically, and the consumer must take it on faith that the supplement they are ingesting is an accurate representation of what is listed on the label, and that it contains the purportedly "active" constituents they seek. Many dietary supplement manufacturers, academic research groups, and governmental organizations are progressively attempting to construct a better scientific understanding of natural products, herbals, and botanical dietary supplements that have co-evolved with Western-style pharmaceutical medicines. However, a deficiency of knowledge is still evident, and this issue needs to be addressed in order to achieve a significant level of safety, efficacy, and quality for commercial natural products. The authors contend that a "quality by design" approach for botanical dietary supplements should be implemented in order to ensure the safety and integrity of these products. Initiating this approach with the authentication of the starting plant material is an essential first step, and in this review several techniques that can aid in this endeavor are outlined.


Assuntos
Produtos Biológicos , Suplementos Nutricionais , Fitoterapia , Plantas Medicinais/química , Qualidade de Produtos para o Consumidor , Humanos , Estados Unidos , Organização Mundial da Saúde
17.
J Pharm Biomed Anal ; 70: 53-63, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22809670

RESUMO

UPLC-UV and HPLC-TOF-MS methods have been developed for the analysis of major sesquiterpenes and pyrrolizidine alkaloids from rhizomes of Petasites hybridus (L.) G.M. et Sch. (Family, Asteracea) and dietary supplements claiming to contain P. hybridus. The best results were obtained with Acquity UPLC™ HSS T3 (100 mm × 2.1 mm, I.D., 1.8 µm) column system using a gradient elution with a mobile phase consisting of ammonium formate (50mM) and acetonitrile (0.05% formic acid) at a constant flow rate of 0.25 mL/min via UPLC-UV. The newly developed method was validated according to the ICH guidelines with respect to specificity, linearity, accuracy and precision. The limits of detection were found to be 5 µg/mL and 0.1 µg/mL for pyrrolizidine alkaloids and sesquiterpenes, respectively by UPLC-UV and 0.001 and 0.01 µg/mL, respectively using HPLC-TOF-MS. The methods were successfully used to analyze different P. hybridus market products, as well as to distinguish between two other Petasites species. The total content of petasins was found to be in the range of 0.02-11.6 mg/dosage form for 15 dietary supplements and no petasins were detected in an additional six dietary supplements. Additionally, pyrrolizidine alkaloids, which are considered to be toxic for the liver, were detected in seven dietary supplements. The amount of petasin in seven dietary supplements was found to be within limits of label claim and no pyrrolizidine alkaloids were detected. HPLC-mass spectrometry coupled with electrospray ionization (ESI) interface method is described for the identification and confirmation of sesquiterpenes and pyrrolizidine alkaloids from plant extracts and dietary supplements that claim to contain P. hybridus as well as different species of Petasites.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Suplementos Nutricionais/análise , Petasites/química , Alcaloides de Pirrolizidina/análise , Rizoma/química , Sesquiterpenos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Ultravioleta , Soluções Tampão , Calibragem , Cromatografia Líquida de Alta Pressão/normas , Cromatografia Líquida/normas , Suplementos Nutricionais/normas , Limite de Detecção , Petasites/classificação , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/normas , Espectrofotometria Ultravioleta/normas
18.
J Pharm Biomed Anal ; 63: 120-7, 2012 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-22342658

RESUMO

Scutellaria lateriflora has been used more than 200 years as a mild relaxant and as a therapy for anxiety, nervous tension, and convulsions. Currently, it is one of the most popular botanicals with many products on the USA market. Flavonoids with anxiolytic property have been reported from the aerial parts of this plant. From the HPLC chromatogram of the methanolic extract of this plant, it can be concluded that some flavonoids have not been identified yet. In the present study a simple high-performance liquid chromatography with UV and electrospray ionization mass spectrometric detection (HPLC-DAD/ESI-MS(n)) method has been developed for the identification of major phenolic compounds from it. The ESI-MS(n) fragmentation pathways of four types of flavonoid references have been interpreted which provide very useful guidance for the characterization of different types of flavonoids from this plant. Further analysis of the methanolic extract of S. latellaria based on the combination of their fragmentation patterns with the UV spectra led to characterize thirteen flavonoids and one stilbene derivative, seven of which are described for the first time from this species.


Assuntos
Ansiolíticos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavonoides/isolamento & purificação , Fenóis/isolamento & purificação , Extratos Vegetais/química , Scutellaria/química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta , Espectrometria de Massas em Tandem , Metanol/química , Estrutura Molecular , Componentes Aéreos da Planta , Plantas Medicinais , Solventes/química
19.
Planta Med ; 77(15): 1742-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21590653

RESUMO

This study describes the first analytical method for the determination of four triterpene saponins (ardisicrenoside B, ardisiacrispin A, 3- O- α- L-rhamnopyranosyl-(1 → 2)-ß-D-glucopyranosyl-(1 → 4)-α-L-arabinopynanosyl cyclamiretin A and ardisimamilloside H) and three alkenated-phenolics (irisresorcinol, belamcandol B, and demethylbelamcandaquinone B) from the leaves, leaves/stems, and roots of LABISIA PUMILA using an HPLC-UV-ELSD method. The separation was achieved using a reversed-phase (C-18) column, PDA and ELS detection, and a water/acetonitrile gradient as the mobile phase. The major triterpenoid (ardisiacrispin A) and irisresorcinol compounds were detected at a concentration as low as 10.0 and 0.2 µg/mL, respectively. Analysis of various samples showed considerable variation of 0.11-2.46 % for the major triterpenoid compound, ardisiacrispin A. LC-mass spectrometry method coupled with electrospray ionization (ESI) is described for the identification of compounds in plant samples. This method involved the use of the [M + Na]+ and [M + NH4]+ ions for compounds 1-4 in the positive ion mode with extractive ion chromatogram (EIC).


Assuntos
Fenóis/análise , Extratos Vegetais/análise , Primulaceae/química , Saponinas/análise , Triterpenos/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida/métodos , Estrutura Molecular , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Saponinas/química , Saponinas/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrofotometria Ultravioleta , Triterpenos/química , Triterpenos/isolamento & purificação
20.
Planta Med ; 77(13): 1562-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21347996

RESUMO

An HPLC method was developed for simultaneous determination of one phenylpropanoid glycoside, verbascoside (1), and nine lignans, including lantibeside (2), phillyrin (3), lantibeside B (4), lantibeside C (5), tibeticoside A (6), styraxjaponoside C (7), sylvatesmin (8), (+)-piperitol (9), and horsfieldin (10), from the Tibetan medicinal plant Lancea tibetica Hook. F. et Thoms. The analysis was performed within 45 min. The extraction method was optimized with different solvent systems. The HPLC method was validated for linearity, repeatability, accuracy, limits of detection, and limits of quantification. The limits of detection and limits of quantification of 10 analytes were found to be less than 0.1 and 0.5 µg/mL, respectively. The RSD for intra- and inter-day analyses was less than 4.2 %, and the recovery efficiency was 90-105 %. The method was used to analyze different populations of L. tibetica collected in China. HPLC profiles showed that the concentrations of analytes were different in samples collected from different areas of China. Verbascoside was the dominant component in three out of five plant samples; compounds 2, 3, 6, and 8 accounted for over 62 % yields in total lignan contents. The method is useful for identification, quality assurance, and quality control of L. tibetica and its related products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Glucosídeos/isolamento & purificação , Lignanas/isolamento & purificação , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Scrophulariaceae/química , Calibragem , China , Glucosídeos/química , Lignanas/química , Medicina Tradicional Tibetana , Fenóis/química , Extratos Vegetais/química , Controle de Qualidade , Raios Ultravioleta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA