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1.
Planta Med ; 87(9): 686-700, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33434940

RESUMO

Lime flowers, traditionally used for medical purposes for the treatment of symptoms of the common cold and mental stress, consist of the dried inflorescences including the floral bracts of Tilia cordata, Tilia platyphyllos, Tilia × vulgaris, or mixtures thereof. During phytochemical investigations, 6 different alkaloids - not described until now - were detected in T. cordata and T. platyphyllos flowers. They have been isolated and characterized as alkaloids with a dihydro-pyrrole and a piperidine substructure, respectively. Compounds 1A: and 1B: (tiliines A and B) are characterized as 2 diastereomers containing a 2-methyl-3,4-dihydro-2H-pyrrol-3-ol, connected via a C-10 alkyl chain to a O-glucosylated hydroquinone moiety. Compounds 2A: and 2B: (tiliamines A and B) are diastereomers of a 2-methyl-substituted piperidin-3-ol, coupled via a C-9 alkyl chain again to an O-glucosylated hydroquinone moiety. Compounds 3A: and 3B: (tilacetines A and B) are 3-O-acetylated derivatives of tiliamines. Quantification of the 6 alkaloids by HPLC-ESI-qTOF analysis indicated the presence of all alkaloids in T. cordata flowers and T. platyphyllos flowers, bracts, and leaves, with tiliines A and B and tilacetines A and B being the major compounds. Acetone/water turned out be the best extraction solvent for the alkaloids, but ethanol and ethanol/water mixtures also can be used for effective extraction. Furthermore, the alkaloids are found in hot water extracts, which are typically used in the traditional medicine.


Assuntos
Alcaloides , Tilia , Flores , Piperidinas , Pirróis
2.
Planta Med ; 81(12-13): 1175-81, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25905592

RESUMO

Proanthocyanidins (condensed tannins) constitute a class of oligomeric and polymeric polyphenols with flavan-3-ols as monomeric building blocks. Despite the high impact of proanthocyanidins, these polyphenols are mostly quantified by colorimetric methods or by chromatographic determination of the flavan-3-ols as cleavage products or low molecular oligomers as lead compounds. For St. John's wort (Hyperici herba) from Hypericum perforatum, a protocol for preparative isolation of oligomeric and polymeric proanthocyanidins from an acetone-water extract by chromatography on Sephadex®LH20 in combination with preparative high-performance liquid chromatography on the diol stationary phase was developed, yielding procyanidin reference clusters with a defined degree of polymerization from 3 to 10. Identity and purity of these clusters was proven by high-performance liquid chromatography (RP18 and diol phase) and mass spectrometry. For identification and quantification of proanthocyanidin clusters from St. John's wort, an ICH-Q2 (International harmonized guideline for analytical validation) validated high-performance liquid chromatography method with fluorimetric detection was developed using an acetone-water extract of the herbal material, purified by solid-phase extraction for the removal of naphthodianthrones. The method enabled the quantification of procyanidin clusters with a degree of polymerization from 2 to 10. Analysis of nine batches of Hyperici herba from different sources indicated a high variability of proanthocyanidin content in the range from 8 to 37 mg/g. In all of the batches investigated, the trimer cluster DP3 was the dominant proanthocyanidin (about 40 %), followed by DP 4 (about 15 %) and DP5 (about 12 %). Monitoring of procyanidin distribution during seasonal growth of fresh plants of H. perforatum indicated the highest proanthocyanidin content in young plants (about 50 mg/g) and a time-dependent decrease during the growing season to about 16 mg/g. The highest proanthocyanidin content was found in young leaves and flowers, while the fruits were proanthocyanidin-free; older parts of the stem and the herb had a lower proanthocyanidin content. From these data, it can be concluded that proanthocyanidins serve as part of the plant defense system in the reproductive organs.


Assuntos
Biflavonoides/isolamento & purificação , Catequina/isolamento & purificação , Hypericum/química , Extratos Vegetais/isolamento & purificação , Proantocianidinas/isolamento & purificação , Antioxidantes , Biflavonoides/análise , Catequina/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Componentes Aéreos da Planta/química , Extratos Vegetais/análise , Polímeros , Proantocianidinas/análise
3.
Molecules ; 20(8): 13764-79, 2015 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-26230683

RESUMO

In the present study, a qualitative analysis of proanthocyanidins (PAs) from an aqueous-methanolic extract of Salix daphnoides VILL. bark is described. Procyanidin B1 (1), B2 (2), B3 (3), B4 (4), C1 (5), epicatechin-(4ß→8)-epicatechin-(4ß→8)-catechin (6) and epicatechin-(4ß→8)-epicatechin-(4ß→8)-epicatechin-(4ß→8)-catechin (7) have been isolated by a combination of different chromatographic separations on Sephadex® LH-20-, MCI®-, Diol-and RP-18-phases. Mass spectrometry, 1D- and 2D-NMR, circular dichroism and polarimetry were used for their structure elucidation and verification by comparison with the literature. Additionally, two fractions of very polar flavan-3-ols were compared: "regular" polymeric PAs received at the very end of the Sephadex® LH-20 chromatography showing no mobility on silica TLC and "unusual" PAs with the same RF-value but already eluting together with flavonoids in the Sephadex® LH-20 system. These "unusual" PAs were subsequently enriched by centrifugal partition chromatography (CPC). 13C-NMR, polarimetry, thiolysis, acid hydrolysis and phloroglucinol degradation were used to characterize both fractions. Differences in the composition of different flavan-3-ol units and the middle chain length were observed.


Assuntos
Proantocianidinas/química , Salix/química , Estrutura Molecular
4.
Molecules ; 20(8): 14810-32, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26287140

RESUMO

Combretum mucronatum Schumach. & Thonn. is a medicinal plant widely used in West African traditional medicine for wound healing and the treatment of helminth infections. The present study aimed at a phytochemical characterization of a hydroalcoholic leaf extract of this plant and the identification of the anthelmintic compounds by bioassay-guided fractionation. An EtOH-H2O (1:1) extract from defatted leaves was partitioned between EtOAc and H2O. Further fractionation was performed by fast centrifugal partition chromatography, RP18-MPLC and HPLC. Epicatechin (1), oligomeric proanthocyanidins (OPC) 2 to 10 (mainly procyanidins) and flavonoids 11 to 13 were identified as main components of the extract. The hydroalcoholic extract, fractions and purified compounds were tested in vitro for their anthelmintic activity using the model nematode Caenorhabditis elegans. The bioassay-guided fractionation led to the identification of OPCs as the active compounds with a dose-dependent anthelmintic activity ranging from 1 to 1000 µM. Using OPC-clusters with a defined degree of polymerization (DP) revealed that a DP ≥ 3 is necessary for an anthelmintic activity, whereas a DP > 4 does not lead to a further increased inhibitory effect against the helminths. In summary, the findings rationalize the traditional use of C. mucronatum and provide further insight into the anthelmintic activity of condensed tannins.


Assuntos
Anti-Helmínticos/farmacologia , Biflavonoides/farmacologia , Bioensaio/métodos , Catequina/farmacologia , Combretum/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Proantocianidinas/farmacologia , Animais , Biflavonoides/química , Caenorhabditis elegans/efeitos dos fármacos , Catequina/química , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Etanol , Polimerização , Proantocianidinas/química , Água
5.
Planta Med ; 79(1): 45-51, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23154843

RESUMO

The rational use of hawthorn leafs and flowers from Crataegus spp. for declining cardiac performance is mainly due to flavon-C-glycosides and oligomeric procyanidins (OPC). From OPC-enriched extracts from different batches, a dimeric phenylpropanoid-substituted procyanidin (cinchonain II b, 1) was isolated and characterized by MS, CD, and NMR. Also the presence of higher oligomeric cinchonains (degree of polymerization 3 to 8) in hawthorn extracts was shown by a specific ultrahigh-pressure liquid chromatography-ESI-qTOF-MS method. Interestingly, strong evidence for the occurrence of oligomeric procyanidin hexosides was found by ultrahigh-pressure liquid chromatography-ESI-qTOF-MS analysis which additionally revealed the presence of peaks indicative of dimeric procyanidin hexosides by their exact mass, which were clearly distinguishable from the cinchonain II type peaks.


Assuntos
Crataegus/química , Glicosídeos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Proantocianidinas/isolamento & purificação , Cromatografia Líquida , Flores/química , Glicosídeos/química , Espectrometria de Massas , Extratos Vegetais/química , Folhas de Planta/química , Proantocianidinas/química
6.
Planta Med ; 76(14): 1550-7, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20309793

RESUMO

Within a systematic phytochemical investigation of the leaves of RHODODENDRON FERRUGINEUM L. (Ericaceae), the volatile oil was isolated (0.7 %) and its constituents were characterized. Eleven flavonoids were isolated and characterized, with quercetin 3- O-[6''- O-(2-methyl-1-oxobutyl)]-ß- D-glucopyranoside and 2 R,3 R-dihydromyricetin 3- O- ß- L-arabinopyranoside as new natural products. Beside monomeric flavan-3-ols (catechin, epicatechin, gallocatechin, epigallocatechin) from the tannin fraction (about 3.5 % calculated as pyrogallol), the dimeric procyanidins B1 to B7 were identified, as well as the trimeric compounds procyanidin C1, epicatechin-(4 ß → 8)-epicatechin-(4 ß → 8)-catechin and the trimeric A type-linked cinnamtannin B1. Additionally, phloroacetophenon 4- O- ß- D-glucopyranoside and chlorogenic acid were isolated. Water-soluble carbohydrates comprised about 13.5 % of the dried leaves, including fructans (3 %), polysaccharides (1 %) (mainly type II arabinogalactans), glucose, fructose, sucrose, stachyose and raffinose. The IN VITRO effects on cellular vitality (MTT test), proliferation (BrdU incorporation) and necrosis (LDH release) of an aqueous extract were investigated. The extract did not exert any toxic effects, while the vitality and the proliferation rates of epithelial HaCaT keratinocytes were significantly increased at 100 µg/mL, indicating that the aqueous extract does not have negative effects against cellular activity.


Assuntos
Flavonoides/toxicidade , Óleos Voláteis/toxicidade , Rhododendron/química , Células Cultivadas , Flavonoides/química , Flavonoides/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Ressonância Magnética Nuclear Biomolecular , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Folhas de Planta/química , Testes de Toxicidade
7.
J Agric Food Chem ; 68(30): 8040-8049, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32633530

RESUMO

Proanthocyanidins (PACs) are complex oligomeric or polymeric phenolic biopolymers composed of flavan-3-ol building blocks. PACs exert manifold functional bioactivities and are assessed as bioactive ingredients in a variety of food products, beverages, medicinal plants, and phytopharmaceuticals. Although analytical methods for PACs with low degree of polymerization (DP) are well established, a lack of methods for the detailed analysis of higher oligomers and polymers from complex plant extracts is obvious. For this, the present study investigated PAC-enriched extracts from four different plants, traditionally used for medical purpose (Lime flower, Hawthorn leaf and flower, Japanese Wisteria fruits without seeds, and Common Sorrel herb). PACs were separated on diol stationary-phase high-performance liquid chromatography according to the respective DP and detected by fluorescence and quadrupole time-of-flight mass spectrometry (qTOF-MS). The qTOF-MS contour plots [tR → m/z] provided a sufficient overview on the respective PAC distribution. Subsequently, high-resolution mass spectrometry data were used for Kendrick mass defect (KMD) analysis, with (epi)catechin, the main flavan-3-ol unit in PACs, as the reference unit. The resulting KMD plots enabled an elucidation of the general polymer chain composition with regard to DP, building blocks, and potential secondary modifications (e.g., galloylation). Subsequently, analysis of MS2 fragmentation patterns of PAC oligomers confirmed the structural features obtained from the KMD plots. While Lime flower contained oligomeric A- and B-type PACs, composed of (epi)catechin and (epi)afzelechin, Japanese Wisteria fruit contained PACs consisting of three different hydroxylated flavan-3-ols. Cinchonains, A-type PACs, and B-type PACs were detected in the Hawthorn plant material. Galloylated oligo- and polymeric PACs were detected in Common Sorrel herb. This multistep analysis reveals collective insights into the PAC composition of the extracts. The protocol offers a fast and reliable methodology to be used in a standard laboratory. On the other hand, this methodology reaches its limits for higher oligomeric PACs, and further optimization is necessary for a better detection of the polymers, as the optimal DP cluster detection depends on the resolution of diol stationary-phase chromatography and is therefore limited.


Assuntos
Citrus/química , Crataegus/química , Extratos Vegetais/química , Proantocianidinas/química , Wisteria/química , Cromatografia Líquida de Alta Pressão , Flores/química , Frutas/química , Folhas de Planta/química , Sementes/química , Espectrometria de Massas por Ionização por Electrospray
8.
J Pharm Pharmacol ; 60(2): 197-204, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18237467

RESUMO

Chitin oligosaccharides (DP2, DP3, DP4, DP5 and DP7) were investigated for their effects on epithelial cells and tissue (skin keratinocytes in-vitro and ex-vivo, and gastrointestinal epithelial membranes exvivo). Oligomers DP2, DP3 and DP5 at 10microg mL(-1) significantly stimulated the mitochondrial activity of cultured keratinocytes in-vitro (primary cells and HaCaT cell line), with highest activity observed for the pentamer (150% of untreated control). The effects were dose dependent. This higher energy status of primary cells was triggered into a higher differentiation status, as determined by the early and late differentiation markers keratins K1/K10 and involucrin, respectively. In contrast, increased mitogenic cell proliferation was not induced by the oligosaccharides. Toxic effects on keratinocytes were absent. Additionally for the first time a mucin-stimulating effect of chitin oligosaccharides DP3 and DP5 was observed in an ex-vivo model based on intestinal epithelial mucosa tissue. Mucin secretion was time dependent, leading to the secretion of polymers comparable to those normally secreted under physiological conditions. Mucin induction was observed from colonic tissue isolated from humans and pigs. Also, porcine stomach mucosa was stimulated by DP5, while ileum tissue reacted to only a minor extent. Potential developments towards products with wound-healing capacity and activity against chronic bowel disease are discussed.


Assuntos
Quitina/farmacologia , Queratinócitos/efeitos dos fármacos , Mucinas/efeitos dos fármacos , Oligossacarídeos/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Quitina/administração & dosagem , Quitina/química , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Trato Gastrointestinal/citologia , Trato Gastrointestinal/metabolismo , Humanos , Queratinócitos/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mucinas/metabolismo , Oligossacarídeos/administração & dosagem , Oligossacarídeos/química , Suínos , Fatores de Tempo
9.
Molecules ; 14(1): 36-45, 2008 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-19104484

RESUMO

From the ethyl acetate soluble fraction of a methanol/water extract of the herb Eupatorium perfoliatum L. (Asteraceae) six caffeic acid derivatives have been isolated and identified by 1D- and 2D-NMR spectroscopic data. Besides the common quinic acid derivatives 5-caffeoylquinic acid (chlorogenic acid), 3-caffeoylquinic acid (neochlorogenic acid) and 3,5-dicaffeoylquinic acid, three up to now unknown depsides of caffeic acid with glucaric acid have been isolated: 2,5-dicaffeoylglucaric acid, 3,4-dicaffeoylglucaric acid, and 2,4- or 3,5-dicaffeoylglucaric acid.


Assuntos
Ácidos Cafeicos/química , Ácido Clorogênico/análogos & derivados , Eupatorium/química , Ácido Quínico/análogos & derivados , Ácidos Cafeicos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Ácido Quínico/química , Ácido Quínico/isolamento & purificação
10.
Fitoterapia ; 130: 169-174, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30176279

RESUMO

Human hyaluronidase-1 (Hyal-1) is one of the main enzymes in the homeostasis of hyaluronic acid (HA), the main polysaccharide of extracellular matrix. Development of specific Hyal-1 inhibitors might be a promising target for improved wound healing, tissue regeneration, and looking at renal function for diuresis. By using surface-displayed Hyal-1 on Escherichia coli F470 cells, HA as substrate and stains-all method for quantification of undegraded HA, the respective enzyme activity can be determined easily. Based on the traditional use of extracts from the roots from Ononis spinosa L. (Restharrow root) as a weak diuretic to achieve flushing of the urinary tract and as an adjuvant in minor urinary complaints the herbal material was selected for bioactivity guided fractionation for compounds with Hyal-1 inhibition activity. Hot water and hydroalcoholic extracts showed moderate inhibiting effects (IC50 1.36 resp. 0.73 mg/mL) while dichloromethane extract exerted an IC50 of 190 µg/mL. Bioassay guided fractionation of the dichloromethane extract yielded four isoflavonoids with anti Hyal-1 activity: onogenin 1, sativanone 2, medicarpin 3 and calycosin-D 4 with inhibition rates of 25.4, 61.2, 22.4 and 23.0%, respectively at test concentration level of 250 µM. The norneolignan clitorienolactone B 5, the first time described for the genus Ononis, was inactive. The IC50 of sativanone, the most active compound was determined with 1501 µM, which was better than that of the positive control glycyrrhizinic acid (177 µM). Thus, a possible explanation for diuretic properties of Ononis spinosa L. root extract may be postulated from the results so far obtained.


Assuntos
Histona Acetiltransferases/antagonistas & inibidores , Hialuronoglucosaminidase/antagonistas & inibidores , Isoflavonas/farmacologia , Lignanas/isolamento & purificação , Ononis/química , Antígenos de Neoplasias , Alemanha , Humanos , Isoflavonas/isolamento & purificação , Isoflavonas/fisiologia , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Raízes de Plantas/química , Plantas Medicinais/química , Pterocarpanos/isolamento & purificação , Pterocarpanos/farmacologia
11.
Fitoterapia ; 118: 87-93, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28288871

RESUMO

Porphyromonas gingivalis is a pathogen strongly involved in chronic and aggressive forms of periodontitis. Natural products, mainly polyphenols, have been described for advanced treatment of periodontitis by inhibition of the bacterial adhesion of P. gingivalis to the epithelial host cells. An acetone:water extract (LBE) from the rhizomes of Limonium brasiliense (Boiss.) Kuntze was tested under in vitro conditions for potential antiadhesive effects against P. gingivalis to human KB cells and for inhibition of the proteolytic activity of gingipains, the main virulence factor of P. gingivalis. LBE≤100µg/mL had no cytotoxicity against the bacteria and did not influence the cell physiology of human epithelial KB cells. At 100µg/mL LBE reduced the adhesion of P. gingivalis to KB cells significantly by about 80%. LBE at 20µg/mL reduced the proteolytic activity of the arginin-specific Rgp gingipain by about 75%. Chemical profiling of LBE indicated the presence of gallic acid, epigallocatechin-3-O-gallate and samarangenins A and B as lead compounds. UHPLC by using MS and UV detection displays a suitable method for quality control of the extract for identification and quantification of the lead compounds.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Flavonoides/química , Plumbaginaceae/química , Porphyromonas gingivalis/efeitos dos fármacos , Proantocianidinas/química , Adesinas Bacterianas/química , Benzopiranos/química , Benzopiranos/isolamento & purificação , Catequina/análogos & derivados , Catequina/química , Catequina/isolamento & purificação , Cisteína Endopeptidases/química , Células Epiteliais/microbiologia , Flavonoides/isolamento & purificação , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Cisteína Endopeptidases Gingipaínas , Humanos , Células KB , Extratos Vegetais/química , Proantocianidinas/isolamento & purificação , Rizoma/química
12.
Nat Prod Res ; 20(13): 1216-24, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17127512

RESUMO

The purified proanthocyanidin oligomers of Cistus salvifolius herb extract accounted for 78% of the total proanthocyanidins and 73% of the total antioxidant activity of this extract. To elucidate the structure of the oligomer, it was depolymerized by acid catalysis in the presence of phloroglucinol. The structures of the resulting flavan-3-ols and phloroglucinol adducts were determined on the basis of 1D- and reverse 2D-NMR (HSQC, HMBC) experiments of their peracetylated derivatives, MALDI-TOF-MS and CD spectroscopy. These observations resulting from the degradation with phloroglucinol were confirmed by 13C NMR spectroscopy of the oligomer. The mean molecular weight of the higher oligomeric fraction was estimated to be 5-6 flavan-3-ol-units.


Assuntos
Antioxidantes/isolamento & purificação , Cistus/química , Proantocianidinas/isolamento & purificação , Antioxidantes/química , Antioxidantes/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Flavonóis/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Rotação Ocular , Floroglucinol/química , Proantocianidinas/química , Proantocianidinas/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
Fitoterapia ; 114: 69-80, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27575326

RESUMO

The upper aerial parts and leaf tips of Myrothamnus flabellifolia Welw. (Myrothamnaceae), a resurrection plant indigenous to southern Africa, are used in African traditional medicine for infections of the respiratory and urinary system as well as for inflammation of mucosa and skin. Within a phytochemical investigation of the herbal material from M. flabellifolia the flavonoid fraction was shown to contain quercetin 10 as well as the respective 3-O-ß-d-galactosides, glucosides, -glucuronides and 3-O-α-l-rhamnosides of quercetin (6, 7, 8, 26) and kaempferol (1, 2, 3, 9). Additionally mono-galloylated 12, 13, di-galloylated 15 and tri-galloylated 16 flavonol glycosides were identified. 3,4,5-Tri-O-galloyl- 14 and 1,3,4,5-tetra-O-galloyl quinic acid 28 were isolated and characterized, beside arbutin 27 and 2″,3″-di-O-galloyl-arbutin 11. Furthermore, the depside 2-O-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxyphenylacetic acid 5, 1,2,3,4,6-penta-O-galloyl-ß-d-glucose 22 and seven ellagitannins were found: 1,2-di-O-galloyl-(4,6-(S)-hexahydroxydiphenoyl)-ß-d-glucose 20, 1,3-di-O-galloyl-(4,6-(S)-hexahydroxydiphenoyl)-ß-d-glucose 21, 2,3-di-O-galloyl-(4,6-(S)-hexahydroxydiphenoyl)-ß-d-glucose (tellimagrandin-I) 19, 1,2,3-tri-O-galloyl-(4,6-O-hexahydroxydiphenoyl)-ß-d-glucose (tellimagrandin-II) 23, and two so far not described dimers of tellimagrandin-I and -II (myrodigamin-I and -II, 24, 25). The presence of trehalose (3.3%), raffinose (0.2%) and stachiose (0.2%) beside a fructan (2.1%) was determined. Two ICH2-validated UHPLC methods have been developed and used within batch analysis for unambiguous identification of the herbal material and quantification of the major compounds myrodigamin-I (0.9 to 1.7%), tellimagrandin-II (0.3 to, 0.9%) and 3,4,5-tri-O-galloyl quinic acid (0.1 to 0.7%), besides kaempferol (0.1 to 0.3%) and quercetin content (0.2 to 0.3%) after hydrolysis of the respective glycosides.


Assuntos
Flavonoides/química , Glicosídeos/química , Magnoliopsida/química , Compostos Fitoquímicos/química , Cromatografia Líquida de Alta Pressão , Flavonoides/isolamento & purificação , Glicosídeos/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Plantas Medicinais/química
14.
Pharmacognosy Res ; 7(1): 14-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25598629

RESUMO

Investigation of the chloroform extract of Euphorbia ammak leaves led to the isolation of three compounds: euphol (1), α-glutinol (2) and stigmasterol (3) Their structures were elucidated by 1D and 2D NMR, as well as by comparison with the reported data. Compounds 1-3 exhibited cytotoxicity in vitro against human cervical adenocarcinoma (Hela), among which, compound 1 showed the best activity.

15.
Fitoterapia ; 105: 246-53, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26210697

RESUMO

The dried stigmata from Zea mays L. are used traditionally for the treatment of uncomplicated urinary tract infections. A recent screening has indicated that hydroalcoholic extract of the herbal material inhibits the adhesion of uropathogenic Escherichia coli (UPEC) to T24 bladder cells. For verification of these data EtOH-water (1:1) extracts from 4 different batches of Maydis stigmata were investigated. Within an in vitro adhesion assay (UPEC strain 2980 and human T24 bladder cells) a dose-dependent antiadhesive activity against UPEC was verified (IC50 1040µg/mL). Bioassay guided fractionation of M. stigmata, batch S1, by EtOH-water extraction, followed by chromatography on Sephadex LH20 revealed two active fractions (I and XI). Further purification of fraction I and structure elucidation of the isolated compound revealed the presence of significant amounts of the biocide benzethonium chloride as contaminant. Benzethonium chloride was also identified in subsequent investigations in 2 different batches of M. stigmata. The presence of such nondeclared and illegal contaminants in the herbal raw material market has to be discussed intensively. From benzethonium-free raw material (batch S2) as well as from batch S1 fraction XI was further fractionated by MPLC and preparative HPLC, leading to a still complex subfraction XIG, which was analyzed by UHPLC/+ESI-QTOF-MS analysis. Advanced data processing and species-metabolite relationship database revealed the tentatively existence of the unusual C-glycosidic flavones derhamnosylmaysin (6), 3'-deoxyrhamnosylmaysin (4), 3'-O-methylderhamnosylmaysin (3), apiferol (2) and alternanthin (8) which might be related to the antiadhesive activity of this subfraction against UPEC.


Assuntos
Antibacterianos/farmacologia , Flavonas/farmacologia , Plantas Medicinais/química , Escherichia coli Uropatogênica/efeitos dos fármacos , Zea mays/química , Aderência Bacteriana/efeitos dos fármacos , Benzetônio/farmacologia , Linhagem Celular , Flores/química , Humanos , Estrutura Molecular , Extratos Vegetais/farmacologia , Bexiga Urinária/citologia , Infecções Urinárias/tratamento farmacológico
16.
Life Sci ; 73(5): 627-39, 2003 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-12770617

RESUMO

Herbal extracts of Hypericum perforatum L. (St. John's wort, SJW) are now successfully competing for status as a standard antidepressant therapy. Because of this, great effort has been devoted to identifying the antidepressive active compounds. In the present study we used the following strategy to evaluate the relative pharmacological importance of various extract components: 1. preparation of an hydroalcoholic SJW extract containing both hyperforin (3.2%) and hypericin (0.15%) (extract A); 2. step by step removal of hyperforin and hypericin led to the following extracts: Extract B, devoid of hyperforin but still containing hypericin (0.14%) and Extract C, free of hypericin and hyperforin but enriched in flavonoids ( approximately 12%). We characterized the in vivo activity profile of all three preparations using the tail suspension test (TST) in mice and the forced swimming test (FST) in rats as screening models. We further investigated the activity of pure hyperforin. Extract B and C (500 mg/kg each) as well as pure hyperforin (8 mg/kg) significantly shortened immobility time in the TST after acute pre-treatment whereas extract A was inactive. In the FST all three extracts decreased immobility time in a dosage of 500 mg/kg after acute as well as after repeated treatment. The present results clearly show that an SJW extract free of hyperforin and hypericin exerts antidepressant activity in behavioral models, supporting our working hypothesis that flavonoids are part of the constituents responsible for the therapeutic efficacy of SJW extracts. We also could show that hyperforin contributes to the beneficial properties of SJW extract, confirming the hypothesis that the crude SJW extract contains several constituents with antidepressant activity.


Assuntos
Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Hypericum/química , Perileno/análogos & derivados , Perileno/farmacologia , Terpenos/farmacologia , Administração Oral , Animais , Antracenos , Antidepressivos/administração & dosagem , Antidepressivos/isolamento & purificação , Compostos Bicíclicos com Pontes , Feminino , Masculino , Camundongos , Camundongos Endogâmicos , Atividade Motora/efeitos dos fármacos , Perileno/administração & dosagem , Perileno/isolamento & purificação , Floroglucinol/análogos & derivados , Esforço Físico/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Ratos , Ratos Endogâmicos , Natação , Terpenos/administração & dosagem , Terpenos/isolamento & purificação
17.
Sci Pharm ; 82(4): 835-46, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26171328

RESUMO

Eleven hydroxycinnamic acid derivatives were isolated from a 70% methanolic Crataegus extract (Crataegi folium cum flore) and partly verified and quantified for individual Crataegus species (C. laevigata, C. monogyna, C. nigra, C. pentagyna) by HPLC: 3-O-(E)-p-coumaroylquinic acid (1), 5-O-(E)-p-coumaroyl-quinic acid (2), 4-O-(E)-p-coumaroylquinic acid (3), 3-O-(E)-caffeoylquinic acid (4), 4-O-(E)-caffeoylquinic acid (5), 5-O-(E)-caffeoylquinic acid (6), 3,5-di-O-(E)-caffeoylquinic acid (7), 4,5-di-O-(E)-caffeoylquinic acid (8), (-)-2-O-(E)-caffeoyl-L-threonic acid (9), (-)-4-O-(E)-caffeoyl-L-threonic acid (10), and (-)-4-O-(E)-p-coumaroyl-L-threonic acid (11). Further, (-)-2-O-(E)-caffeoyl-D-malic acid (12) was isolated from C. submollis and also identified for C. pentagyna and C. nigra by co-chromatography. The isolates 10 and 11 were not found in the authentic fresh specimen, indicating that they may be formed during extraction by acyl migration from the 2-O-acylderivatives. Also, 9 and 11 are described here for the first time. All structures were assigned on the basis of their spectroscopic data ((1)H-, (13)C-NMR, MS, optical rotation).

18.
Fitoterapia ; 99: 252-60, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25454458

RESUMO

Extracts from Poincianella pluviosa stem bark are used in traditional medicine of South America for its wound healing properties. For validation of this traditional use and for rationalizing a potential pharmaceutical development towards standardized preparations bioassay-guided fractionation of EtOH-water (1:1v/v) extract (crude extract, CE) of P. pluviosa bark was performed. HaCaT keratinocytes cell line and human primary dermal fibroblasts (pNHDF) were used as in vitro systems. Significant stimulation of mitochondrial activity was found for CE on both cell types, which caused a strong increase of cell proliferation of keratinocytes. Fractionation of CE over Sephadex LH20 revealed two inactive fractions (FA and FB) and an active fraction FC, which was further fractionated by MPLC into 4 subfractions. Subfraction FC1 increased mitochondrial activity and proliferation of keratinocytes and dermal fibroblasts in a dose dependent manner (10 to 100 µg/mL) and did not show necrotic cytotoxicity on keratinocytes (LDH release assay). FC1 was investigated by ESI-MS/MS and solid-state (13)C NMR which confirmed the presence of various polyphenols and hydrolyzable tannins. MS studies suggest the presence of pyrogallol (1), gallic acid (2), gallic acid methyl ester (3), ellagic acid (4), corilagin (5), 1,4,6-tri-O-galloyl-glucose (6), tellimagrandin I (7), 1,2,3,6-tetra-O-galloyl-glucose (8), mallotinic acid (9), tellimagrandin II (10), 1,2,3,4,6-penta-O-galloyl-glucose (11), geraniin (12), and mallotusinic acid (13).


Assuntos
Fabaceae/química , Fibroblastos/efeitos dos fármacos , Taninos Hidrolisáveis/química , Queratinócitos/efeitos dos fármacos , Cicatrização , Linhagem Celular , Humanos , Estrutura Molecular , Casca de Planta/química , Extratos Vegetais/farmacologia , Polifenóis/química
19.
J Ethnopharmacol ; 155(1): 165-70, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-24862489

RESUMO

UNLABELLED: ETNOPHARMACOLOGICAL RELEVANCE: The popularity of concentrated green tea extracts as dietary supplements for a wide range of applications is increasing due to their health-promoting effects attributed to the high amounts of catechins they contain. The most important of the green tea catechins is (-)-epigallocatechin-3-O-gallate (EGCG). While their beneficiary effects have been studied extensively, a small number of adverse events have been reported in the medical literature. Here we present a typical reversible course of severe hepatitis after green tea consumption. MATERIALS AND METHODS: The case study describes in a 63-year old woman during treatment with green tea-capsules upon recommendation of a cancer support group. RESULTS: The histological finding was consistent with drug induced hepatitis, and other possible causes of hepatitis were excluded. According to the CIOMS/RUCAM score the causality was assessed as "probable". After discontinuation of medication, followed by extracorporal albumin dialysis, rapid and sustained recovery occurred. Pharmaceutically analysis (HPLC) of the green tea capsules did not give evidence for contaminants but revealed the two typical compounds of green tea, namely (-)-epigallocatechin-3-O-gallate (EGCG, 93.2%) and epicatechin (EC, 6.8%) at a very high dose level. CONCLUSION: The present case highlights the fact that such concentrated herbal extracts from green tea may not be free of adverse effects under certain circumstances. There is still a lack of a uniform European Union-wide surveillance system for adverse drug reactions of herbal products. Therefore this case underlines the importance of public awareness in the potential risks in use of herbal products.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Suplementos Nutricionais/efeitos adversos , Extratos Vegetais/efeitos adversos , Chá , Doença Aguda , Camellia sinensis/química , Catequina/análogos & derivados , Catequina/isolamento & purificação , Doença Hepática Induzida por Substâncias e Drogas/fisiopatologia , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Pessoa de Meia-Idade , Extratos Vegetais/química , Índice de Gravidade de Doença
20.
J Ethnopharmacol ; 145(2): 591-7, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23211661

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Investigation of medicinal plant extracts traditionally used against uncomplicated urinary tract infections (UTI) and identification of antiadhesive effects under in vitro conditions against binding of uropathogenic Escherichia coli (UPEC) on bladder cell surface. MATERIALS AND METHODS: Literature search on traditionally used medicinal plants for UTI was performed by online data bases and standard herbal monographs. For further identification shortlisting was done by intensive evaluation of results by plausibility and phytochemical aspects. Plant material with documented antibacterial effects was not considered for further investigations. Direct cytotoxicity of EtOH-water (1:1; v/v) extracts of the shortlisted plants was investigated against UPEC strain 2980 and bladder cell line T24. Inhibition of UPEC adhesion to T24 cells was monitored either after pretreatment of bacteria or eukaryotic cells by flow cytometry. RESULTS: Literature search on traditionally used medicinal plants for UTI resulted in 275 plant species, from which 20 were shortlisted by a validated selection process for experimental testing. While direct cytotoxicity of the extracts (1-2000 µg/mL) against UPEC and T24 cells was excluded significant antiadhesive effects were monitored for five plant extracts. Two of them, prepared from the rhizome of Agropyron repens L. and the stigmata of Zea mays L. decreased bacterial adhesion (IC(25) 630 µg/mL, IC(50) 1040 µg/mL, resp.) by interacting with bacterial outer membrane proteins, which was shown by pretreatment of UPEC. Preparations of three plant extracts from the leaves of Betula spp. (according to European pharmacopoeia 7.0), Orthosiphon stamineus BENTH. and Urtica spp. showed antiadhesive effects by interacting with T24 cells (IC(50) 415, 1330 µg/mL, resp. IC(25) 580 µg/mL). Combination of two extracts, one interacting with the bacterial surface (Zea mays L., Agropyron repens L.) and one with the eukaryotic target (Orthosiphon stamineus BENTH.) revealed synergistic effects, as shown by strongly decreased IC(50) values (131 µg/mL, 511 µg/mL, resp.). CONCLUSIONS: Different plant extracts, traditionally used for UTI, exhibit antiadhesive effects against UPEC under in vitro conditions. Molecular targets can be different, either on the bacterial or on the host cell surface. Combination of these medicinal plants with different targets, as observed often in phytotherapy, results in synergistic effects.


Assuntos
Extratos Vegetais/farmacologia , Plantas Medicinais , Escherichia coli Uropatogênica/efeitos dos fármacos , Agropyron , Antibacterianos/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Escherichia coli Uropatogênica/fisiologia , Zea mays
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