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1.
Molecules ; 29(1)2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38202796

RESUMO

Xylobolus subpileatus is a widely distributed crust fungus reported from all continents except Antarctica, although considered a rare species in several European countries. Profound mycochemical analysis of the methanol extract of X. subpileatus resulted in the isolation of seven compounds (1-7). Among them, (3ß,22E)-3-methoxy-ergosta-4,6,814,22-tetraene (1) is a new natural product, while the NMR assignment of its already known epimer (2) has been revised. In addition to a benzohydrofuran derivative fomannoxin (3), four ergostane-type triterpenes 4-7 were identified. The structure elucidation of the isolated metabolites was performed by one- and two-dimensional NMR and MS analysis. Compounds 2-7 as well as the chloroform, n-hexane, and methanol extracts of X. subpileatus were evaluated for their tyrosinase, acetylcholinesterase, and butyrylcholinesterase inhibitory properties. Among the examined compounds, only fomannoxin (3) displayed the antityrosinase property with 51% of inhibition, and the fungal steroids proved to be inactive. Regarding the potential acetylcholinesterase (AChE) inhibitory activity of the fungal extracts and metabolites, it was demonstrated that the chloroform extract and compounds 3-4 exerted noteworthy inhibitory activity, with 83.86 and 32.99%, respectively. The butyrylcholinesterase (BChE) inhibitory assay revealed that methanol and chloroform extracts, as well as compounds 3 and 4, exerted notable activity, while the rest of the compounds proved to be only weak enzyme inhibitors. Our study represents the first report on the chemical profile of basidiome of the wild-growing X. subpileatus, offering a thorough study on the isolation and structure determination of the most characteristic biologically active constituents of this species.


Assuntos
Basidiomycota , Inibidores da Colinesterase , Inibidores da Colinesterase/farmacologia , Acetilcolinesterase , Butirilcolinesterase , Clorofórmio , Metanol , Extratos Vegetais
2.
J Chromatogr A ; 1677: 463308, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35858490

RESUMO

The present work introduces a high-performance thin-layer chromatography (HPTLC)-direct bioautography method using the Gram-positive plant pathogenic bacterium, Rhodococcus fascians. The screening and isolation procedure comprised of a non-targeted high-performance thin-layer chromatography-effect-directed analysis (HPTLC-EDA) against Bacillus subtilis, B. subtilis subsp. spizizenii, R. fascians, and Aliivibrio fischeri, a targeted HPTLC-mass spectrometry (MS), and bioassay-guided column chromatographic (preparative flash and semi-preparative HPLC) fractionation and purification. The developed new separation methods enabled the discovery of four bioactive cis-clerodane diterpenes, solidagoic acid H (1), solidagoic acid E (2), solidagoic acid I (3), and solidagoic acid F (4), in the n-hexane extract of giant goldenrod (Solidago gigantea Ait.) leaf for the first time. These compounds were identified by 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. The initially used HPTLC method (chloroform - ethyl acetate - methanol 15:3:2, V/V/V) was changed (to n-hexane - isopropyl acetate - methanol - acetic acid 29:20:1:1, V/V/V/V) to achieve the separation of the closely related isomer pairs (1-2 and 3-4). Compounds 1 and 3 exhibited moderate antibacterial activity against the Gram-positive B. subtilis subsp. spizizenii and R. fascians bacterial strains in microdilution assays with half-maximal inhibitory concentration (IC50) values in the range of 32.3-64.4 µg/mL. The mass spectrometric fragmentation of the isolated compounds was interpreted and their previously published NMR assignments lacking certain resonances were completed.


Assuntos
Diterpenos Clerodânicos , Solidago , Antibacterianos , Bacillus subtilis , Bioensaio , Cromatografia em Camada Fina/métodos , Metanol , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Solidago/química
3.
Orv Hetil ; 163(9): 343-349, 2022 02 27.
Artigo em Húngaro | MEDLINE | ID: mdl-35220272

RESUMO

Összefoglaló. A Magyar és az Európai Hypertonia Társaság legújabb ajánlásában a gyógyszer okozta szekunder hypertoniák gyakoribb okai között szerepel az Ephedra - csikófark (kínai nevén Mahuang) fajok drogjának (Ephedrae herba) felhasználása is. Összefoglaló közleményünk célja az Ephedra nemzetségbe tartozó, a gyógyászatban is felhasznált, a VIII. Magyar Gyógyszerkönyvben és a Kínai Gyógyszerkönyvben szereplo hivatalos fajoknak a részletes bemutatása. Betekintést nyújtunk történetükbe, továbbá leírjuk a bennük található vegyületek farmakológiai tulajdonságait és azok hatásait. Ismertetjük elonyeiket, mellékhatásaikat és lehetséges gyógyszerkölcsönhatásaikat. Ezenkívül feltárjuk fogyasztó- és testsúlycsökkento szerként való használatukat, étrend-kiegészítoként történo alkalmazásuk betiltásának okát, valamint tárgyaljuk a doppinglistán való szereplésük magyarázatát is. Ezzel párhuzamosan kitérünk az Ephedra fajok orvosi gyakorlatban betöltött szerepére is: rendeltetésszeru használatuk során a fitoterápiában - foleg kombinációban alkalmazva - számos jótékony hatás érheto el, de fontos hangsúlyozni óvatos használatukat és felismerni lehetséges mellékhatásaikat. Orv Hetil. 2022; 163(9): 343-349. Summary. The Hungarian and the European Society of Hypertension guidelines mention Ephedrae herba, the drug of Ephedra species (in Chinese "Mahuang") as one of the causes of secondary hypertension. The aim of our summary is to characterize the Ephedra species used in medicine (based on the VIII. Hungarian and the Chinese Pharmacopoeia), describe their history and their components alongside with possible pharmacological effects, benefits, side-effects, and interactions with other drugs. We demonstrate the herb's history from being a popular weight-loss product to being prohibited as a dietary supplement and citing it in the World Anti-Doping Agency's list. At the same time, we explain the role of the Ephedra species in the everyday medical practice. It is important to know their benefits in detail as used in combination with other herbs in phytotherapy, and recognize their possible side effects. Orv Hetil. 2022; 163(9): 343-349.


Assuntos
Redução de Peso , Humanos , Hungria
4.
J Pharm Biomed Anal ; 210: 114554, 2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-34973466

RESUMO

Detailed polyphenol profiling of European hornbeam (Carpinus betulus L.) bark, leaf, male and female catkin extracts was performed by high-performance liquid chromatography-diode array detection coupled to tandem mass spectrometry (HPLC-DAD-MS/MS). A total of 194 compounds were characterized and tentatively identified. Gallo- and ellagitannins dominated in the methanol extracts, while flavonol glycosides and methoxylated flavones prevailed in the ethyl acetate samples. In the quest for diarylheptanoids, twelve compounds were isolated by the combination of subsequent reversed-phase flash chromatographic and high-performance liquid chromatographic methods. The structural elucidation of the isolated components was performed by ultrahigh-performance liquid chromatography-Orbitrap mass spectrometry (UHPLC-Orbitrap-MS) as well as 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. Six known cyclic diarylheptanoids, together with a new compound were described in Carpinus betulus for the first time. The occurrence of a linear diarylheptanoid and a lignan has also been unprecedented in the genus Carpinus. Moreover, three known flavonol glycosides were isolated. Based on the identification of characteristic fragment ions, a new mass spectrometric fragmentation pathway for meta,meta-cyclophane-type diarylheptanoids was proposed. Quantities of the four major cyclic diarylheptanoids in European hornbeam were determined by a validated UHPLC-DAD method for the first time. The antioxidant properties of the extracts and the isolated compounds were assessed by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Contribution of the individual constituents to the total radical scavenging activity of the samples was evaluated by an off-line DPPH-HPLC-DAD method. This allowed the identification of gallo- and ellagitannin derivatives as the constituents being primarily responsible for the antioxidant capacity of the extracts.


Assuntos
Antioxidantes , Diarileptanoides , Betulaceae , Cromatografia Líquida de Alta Pressão , Cone de Plantas , Extratos Vegetais , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
5.
J Chromatogr A ; 1635: 461727, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33338903

RESUMO

Giant goldenrod (Solidago gigantea Ait.) root extract was screened for bioactive compounds by high-performance thin-layer chromatography (HPTLC), coupled with effect-directed analysis including antibacterial (Bacillus subtilis F1276, B. subtilis subsp. spizizenii, Aliivibrio fischeri and Xanthomonas euvesicatoria), antifungal (Fusarium avenaceum) and enzyme inhibition (acetyl- and butyrylcholinesterases, α- and ß-glucosidases and α-amylase) assays. Compounds of six multipotent zones (Sg1-Sg6) were characterized by HPTLC-heated electrospray ionization-high-resolution mass spectrometry (HRMS) and HPTLC-Direct Analysis in Real Time-HRMS. Apart from zone Sg3, containing three compounds, a single characteristic compound was detectable in each bioactive zone. The bioassay-guided isolation using preparative-scale flash chromatography and high-performance liquid chromatography provided eight compounds that were identified by NMR spectroscopy as clerodane diterpenes. All isolates possessed inhibiting activity against at least one of the tested microorganisms.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Diterpenos Clerodânicos/farmacologia , Fusarium/efeitos dos fármacos , Extratos Vegetais/farmacologia , Solidago/química , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Bacillus subtilis/efeitos dos fármacos , Colinesterases/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Diterpenos Clerodânicos/isolamento & purificação , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Xanthomonas/efeitos dos fármacos
6.
J Chromatogr A ; 1611: 460602, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653473

RESUMO

A high-performance thin-layer chromatography (HPTLC) method was developed for rapid and easy-to-perform discrimination between five goldenrod species present in Europe: the native Solidago virgaurea and the four invasive aliens, S. canadensis, S. gigantea, S. rugosa and S. graminifolia. The chemotaxonomic distinction was based on the chemical profile of their root extracts, confirmed by principal component analysis. This allowed the distinction of the goldenrods in wintertime, when classical morphological methods are not applicable. Their enzyme inhibitory profiles were determined by HPTLC combined with α-glucosidase, ß-glucosidase, α-amylase, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) assays. Two compounds of S. canadensis showed the most intense enzyme inhibition in all assays, having also antibacterial activity against Bacillus subtilis, Xanthomonas euvesicatoria and Aliivibrio fischeri strains. HPTLC-high-resolution mass spectrometry (HRMS), bioassay-guided isolation, NMR spectroscopy and literature data led to the characterization and identification of the labdane diterpenes solidagenone and presolidagenone as the active S. canadensis root components. The previously identified polyacetylenes (2Z,8Z and 2E,8Z matricaria esters) of S. virgaurea, also inhibited all enzymes. Except for the known anti-AChE effect of the 2Z,8Z-matricaria ester, this is the first report on the α-glucosidase, ß-glucosidase, α-amylase, AChE and BChE inhibitory activity of these potent compounds. The anti-hyperglycemic effects of the S. canadensis labdanoids were also observed for the first time. Combined with effect-directed assays and HRMS, hyphenated HPTLC allowed an effect-directed high-throughput screening and a fast characterization of multipotent compounds. The investigation of botanicals by fast, hyphenated, bioanalytical tools substantially increased the information gain with regard to active principles (bioprofiling) and efficiently pointed to potent candidates for drug development.


Assuntos
Extratos Vegetais/química , Raízes de Plantas/química , Solidago/química , Antibacterianos/análise , Fracionamento Químico , Cromatografia em Camada Fina , Compostos Fitoquímicos/análise , Análise de Componente Principal
7.
Front Plant Sci ; 11: 622585, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33584762

RESUMO

Hairy root cultures are genetically and biochemically stable, and they regularly possess the same or better biosynthetic capabilities for specialized (secondary) metabolite production compared to the intact plant. Ononis species are well-known herbal remedies in ethnopharmacology and rich sources of isoflavonoids. Besides isoflavones, less prevalent isoflavones and pterocarpans with valuable biological effects can be found in Ononis species as well. As these plants are only collected but not cultivated, biotechnological methods could play a role in the larger-scale extraction of Ononis isoflavonoids. Regarding this information, we aimed to establish Ononis spinosa and Ononis arvensis hairy root cultures (HRCs) and analyze the isoflavonoid profile of hairy root cultures qualitatively and quantitatively, in order to define their capacity to produce biologically valuable isoflavonoids. During the qualitative description, beside isoflavonoids, two new phenolic lactones, namely, bulatlactone 2″-O-ß-D-glucoside and ononilactone, were isolated, and their structures were characterized for the first time. Altogether, 29 compounds were identified by the means of UPLC-Orbitrap-MS/MS. Based on UHPLC-UV-DAD measurements, the isoflavonoid spectrum of the Ononis HRCs differed markedly from wild-grown samples, as they produce a limited range of the scaffolds. The most abundant compounds in the HRCs were medicarpin glucoside and sativanone glucoside. The overall isoflavonoid production of the cultures was comparable to wild-grown O. arvensis and approximately twice as high as in wild-grown O. spinosa samples. As the overall content of wild-grown samples include more isoflavonoid derivatives, the HRCs contain structurally less divergent isoflavonoids but in higher quantity.

8.
Fitoterapia ; 137: 104180, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31150766

RESUMO

Effect-directed isolation of free radical scavengers from the methanol extract of the freeze-dried fruiting bodies of the cultivated basidiomycetous mushroom, black poplar (Cyclocybe cylindracea), yielded a ß-carboline alkaloid. Its structure was determined based on ESI-TOF-MS/MS, NMR and circular dichroism spectra by comparison with published data. The compound, identified as the C1-S diastereomer of brunnein B, exhibited explicit radical scavenging activity (EC50 = 119.1 ±â€¯1.2 µg/mL). The quantity of the active component was determined with HPLC-MS in the fruiting body (36.2 ±â€¯2.8 ng/g DW, dry weight) and its different tissues such as peel (94.7 ±â€¯1.9 ng/g DW), inner cap (90.5 ±â€¯1.3 ng/g DW), gills (71.5 ±â€¯0.6 ng/g DW), and stipe (162.2 ±â€¯1.7 ng/g DW). It is a ß-carboline alkaloid that was not reported previously.


Assuntos
Agaricales/química , Alcaloides/química , Carbolinas/química , Sequestradores de Radicais Livres/química , Alcaloides/isolamento & purificação , Carbolinas/isolamento & purificação , Sequestradores de Radicais Livres/isolamento & purificação , Hungria , Estrutura Molecular
9.
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
10.
Artigo em Inglês | MEDLINE | ID: mdl-29803686

RESUMO

Spiny restharrow root (Ononis spinosa L.) and its preparations are mainly used for the treatment of urinary infections or bladder stones in numerous countries. Spiny restharrow root is rich in isoflavonoids (formononetin, calycosin and pseudobaptigenin), pterocarpans (medicarpin and maackiain) and dihydroisoflavonoids (onogenin and sativanone), which metabolites are present as glucosides, glucoside malonates, glucoside acetates and free aglycones in the root. The in-depth analysis of tandem mass spectrometric (MS) and high-resolution MS (HR-MS) data revealed the presence of nitrogen-containing compounds in the root extracts. An ion-exchange-based purification and a preparative-scale reversed phase chromatographic isolation procedure was developed for the characterization of these new natural products. For the unambiguous identification of the isolated compounds NMR experiments were carried out. The thorough characterization confirmed the presence of six piperidin-2-yl-acetic acid (homopipecolic acid) esters of isoflavonoid glucosides. This is the first report of homopipecolic acid esters isolated from higher plants.


Assuntos
Isoflavonas/análise , Ononis/química , Ácidos Pipecólicos/análise , Extratos Vegetais/química , Raízes de Plantas/química , Cromatografia Líquida de Alta Pressão/métodos , Ésteres , Isoflavonas/química , Isoflavonas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Ácidos Pipecólicos/química , Ácidos Pipecólicos/isolamento & purificação , Espectrometria de Massas em Tandem
11.
Fitoterapia ; 127: 413-419, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29653155

RESUMO

While analyzing the fruit composition of nine European Cirsium species representing three sections (i.e., Cephalonoplos, Chamaeleon and Eriolepis), four lignans, three neolignans and three sesquineolignans were determined and used as chemotaxonomic markers. Among them, desmethyl balanophonin and desmethyl picrasmalignan were determined for the first time in the plant kingdom, as the main metabolites of the Chamaeleon section. Prebalanophonin and prepicrasmalignan, identified so far exclusively in C. eriophorum, were also confirmed in C. boujartii and C. vulgare, highlighting the chemotaxonomic significance of these compounds in the Eriolepis section. The antiproliferative assay of the compounds isolated from their optimum sources, confirmed a dose-dependent inhibitory effect of the structures bearing the 4',7-epoxy moiety (balanophonin, picrasmalignan, desmethyl balanophonin, desmethyl picrasmalignan) against SW480 colon cancer cells, while those bearing the 4',7-dihydroxy motif (prebalanophonin, prepicrasmalignan) were inactive.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Cirsium/química , Frutas/química , Lignanas/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Humanos , Lignanas/farmacologia , Estrutura Molecular , Compostos Fitoquímicos/análise
12.
J Pharm Biomed Anal ; 149: 488-493, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29182998

RESUMO

Feverfew (Tanacetum parthenium L.) as a perennial herb has been known for centuries due to its medicinal properties. The main sesquiterpene lactone, parthenolide is considered to be responsible for the migraine prophylactic effect, however the pharmacological benefits of the lipophilic flavonoid components can not be neglected. Supercritical fluid extraction (7% ethanol, 22MPa, 64°C) was carried out on the leaves of Tanacetum parthenium L. from which the presence of methylated flavonoids beside parthenolide and other sesquiterpene lactones were indicated by preliminary LC-MS analyses. Specific Parallel Artificial Membrane Permeability Assay (PAMPA) was applied to identify the components capable to cross the Blood-Brain Barrier (BBB). Three lipophilic flavonoids were detected on the acceptor side, that were isolated (Prep-HPLC) and identified as sudachitin, aceronin and nevadensin (LC-MS/MS, NMR). These flavonoids were also characterized individually by PAMPA-BBB model. The presence of sudachitin and nevadensin was proven in the Asteraceae family, but neither of the three flavonoids were reported in Tanacetum parthenium L.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Flavonoides/farmacocinética , Extratos Vegetais/farmacocinética , Plantas Medicinais/química , Tanacetum parthenium/química , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/instrumentação , Cromatografia com Fluido Supercrítico/métodos , Flavonas/química , Flavonas/farmacocinética , Flavonoides/química , Glicosídeos/química , Glicosídeos/farmacocinética , Lipídeos/química , Extratos Vegetais/química , Folhas de Planta/química , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos
13.
J Chromatogr A ; 1533: 213-220, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29269147

RESUMO

High-performance thin-layer chromatography (HPTLC) coupled with effect-directed analysis was used for non-targeted screening of sunflower leaf extract for components exhibiting antioxidant, antibacterial and/or cholinesterase enzyme inhibitory effects. The active compounds were characterized by HPTLC-electrospray ionization-high resolution mass spectrometry (ESI-HRMS) and HPTLC-Direct Analysis in Real Time (DART)-MS/MS. The latter ambient ionization technique (less soft than ESI) resulted in oxidation and fragmentation products and characteristic fragment ions. NMR spectroscopy after targeted isolation via preparative normal phase flash chromatography and semi-preparative reversed phase high-performance liquid chromatography supported the identification of two diterpenes to be (-)-kaur-16-en-19-oic acid and 15-α-angeloyloxy-ent-kaur-16-en-19-oic acid. Both compounds found to be multi-potent as they inhibited acetylcholinesterase and butyrylcholinesterase and showed antibacterial effects against Gram-positive Bacillus subtilis and Gram-negative Aliivibrio fischeri bacteria. Kaurenoic acid was also active against the Gram-negative pepper pathogenic Xanthomonas euvesicatoria bacteria.


Assuntos
Cromatografia em Camada Fina , Helianthus/química , Extratos Vegetais/química , Folhas de Planta/química , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Colinesterases/metabolismo , Ativação Enzimática/efeitos dos fármacos , Extratos Vegetais/análise , Espectrometria de Massas por Ionização por Electrospray
14.
Nat Prod Res ; 32(17): 2058-2061, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28750545

RESUMO

Quantitative phytochemical characterisation of the chief flavonoid aglycones in the hydrolysed Lysimachia extracts revealed the dominance of kaempferol, quercetin and myricetin in L. vulgaris, L. nummularia, L. punctata, L. christinae, L. ciliata and L. clethroides, respectively. Due to the significant radical scavenging capacity of the samples, the contribution of the individual aglycones to the total antioxidant activity became of interest. Therefore, a HPLC method coupled to pre-column DPPH scavenging assay was developed. Differences in the six Lysimachia species' phenolic composition regarding their participation to the antioxidant activity were revealed. The participation of the three investigated flavonoids to the radical quenching activity was the highest (91.2%) in the L. vulgaris sample, the lowest in L. christinae sample with 29.6%. In L. vulgaris sample, the 76.3% contribution of quercetin to the scavenger capacity was the highest peak area decrement ratio among the investigated samples.


Assuntos
Antioxidantes/isolamento & purificação , Flavonoides/farmacologia , Primulaceae/química , Antioxidantes/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Fenóis/química , Extratos Vegetais/química
15.
J Chromatogr A ; 1524: 266-272, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-28989030

RESUMO

The antibacterial profiling of Onopordum acanthium L. leaf extract and subsequent targeted identification of active compounds is demonstrated. Thin-layer chromatography (TLC) and off-line overpressured layer chromatography (OPLC) coupled with direct bioautography were utilized for investigation of the extract against eight bacterial strains including two plant and three human pathogens and a soil, a marine and a probiotic human gut bacteria. Antibacterial fractions obtaining infusion-transfusion OPLC were transferred to HPLC-MS/MS analysis that resulted in the characterization of three active compounds and two of them were identified as, linoleic and linolenic acid. OPLC method was adopted to preparative-scale flash chromatography for the isolation of the third active compound, which was identified after a further semi-preparative HPLC purification as the germacranolide sesquiterpene lactone onopordopicrin. Pure onopordopicrin exhibited antibacterial activity that was specified as minimal inhibitory concentration in the liquid phase as well.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bioensaio , Cromatografia em Camada Fina , Onopordum/química , Extratos Vegetais/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Humanos , Lactonas/isolamento & purificação , Lactonas/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Folhas de Planta/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Espectrometria de Massas em Tandem
16.
Artigo em Inglês | MEDLINE | ID: mdl-28384606

RESUMO

High amount of the valuable lignan pinoresinol (PR) was determined in Carduus nutans fruit (7.8mg/g) for the first time. A preparative separation method using two consecutive, identical steps of centrifugal partition chromatography (CPC) was developed in order (i) to isolate PR and (ii) to subsequently isolate PR and its 7' epimer epipinoresinol (EPR) simultaneously after an optimized acid treatment which resulted in PR epimerization forming equal amounts of PR and EPR, from C. nutans fruit. As optimal conditions, a two-phase solvent system consisting of methyl tert-butyl ether:acetone:water (4:3:3, v/v/v) for CPC separation, and an acid treatment performed at 50°C for 30min for the epimerization were applied. Thus, 33.7mg and 32.8mg PR and EPR, in as high as 93.7% and 92.3% purity, were isolated from 10.0gC. nutans fruit, representing 86.4% and 84.1% efficiency, respectively. Conversion characteristic of PR and EPR in acidic medium, determined as a function of time and temperature of acid treatment provides their unambiguous identification by on-line high performance liquid chromatography (HPLC). Antiproliferative assay of isolated PR and EPR in two different types of colon cancer cell lines (HCT116 and SW480) confirmed that both epimers caused a more significant decrease of viability in HCT116 cells than in SW480 cells, suggesting their similar mechanism of antiproliferative action.


Assuntos
Antineoplásicos Fitogênicos/análise , Carduus/química , Cromatografia Líquida de Alta Pressão/métodos , Furanos/análise , Lignanas/análise , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Frutas/química , Furanos/isolamento & purificação , Furanos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Células HCT116 , Humanos , Lignanas/isolamento & purificação , Lignanas/farmacologia , Extratos Vegetais/química , Estereoisomerismo
17.
Anal Chem ; 88(16): 8202-9, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27433973

RESUMO

A nontargeted, effect-directed screening (bioprofiling) and a subsequent highly targeted characterization of antibacterial compounds from plant matrices is demonstrated on the example of Solidago virgaurea root extracts. The procedure comprises high-performance thin-layer chromatography (HPTLC) coupled with six bacterial bioassays including two plant pathogens, a radical scavenging assay, an acetylcholinesterase assay as well as in situ and ex situ mass spectrometric analyses. In situ mass spectra were directly recorded from the adsorbent using the Direct Analysis in Real Time interface (HPTLC-DART-MS), whereas ex situ mass spectra were recorded using an elution head-based interface (HPTLC-ESI-MS). For further bioassay-guided isolation of the main antimicrobial compounds, flash chromatographic fractionation and semipreparative high-performance liquid chromatographic purification were used and nuclear magnetic resonance data allowed the identification of the unknown antimicrobial compounds as 2Z,8Z- and 2E,8Z-matricaria esters. The discovered antibacterial activity was confirmed and specified by a luminometric assay and as minimal inhibitory concentration in the liquid phase.


Assuntos
Antibacterianos/análise , Extratos Vegetais/química , Solidago/química , Espectrometria de Massas por Ionização por Electrospray , Antibacterianos/isolamento & purificação , Inibidores da Colinesterase/análise , Inibidores da Colinesterase/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Espectroscopia de Ressonância Magnética , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Microextração em Fase Sólida , Solidago/metabolismo
18.
Nat Prod Commun ; 11(4): 469-74, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27396195

RESUMO

Semnpervivum tectorum L. and Corylus avellana L. are traditional herbal remedies exhibiting antioxidant activity and representing diverse phenolic composition. The aim of this study was to reveal the contribution of certain compounds to total radical scavenging activity by studying S. tectorum and C. avellana extracts prepared with solvents of different selectivity for diverse classes of phenolics. Antioxidant activity of S. tectorum and C. avellana samples was determined in the ABTS and DPPH radical scavenging assays, and phenolic composition was evaluated by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Correlations between antioxidant activity and phenolic content of houseleek extracts have been revealed. Significant differences regarding antioxidant activity have been shown between S. tectorum 80% (v/v) methanol extract and its fractions. Additionally, synergism among the constituents present together in the whole extract was assumed. Significantly higher radical scavenging activity of hazel extracts has been attributed to the differences in phenolic composition compared with houseleek extracts.


Assuntos
Corylus/química , Crassulaceae/química , Sequestradores de Radicais Livres/análise , Fenóis/análise , Extratos Vegetais/química
19.
Biomed Chromatogr ; 30(12): 2031-2037, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27324458

RESUMO

Feverfew (Tanacetum parthenium L., Asteraceae) is a perennial medicinal plant which has been used to alleviate the symptoms of migraine, headache and rheumatoid arthritis and possesses numerous pharmacological activities. An ultra-high-performance supercritical fluid chromatographic method (UHPSFC) was developed and validated in accordance with the International Conference on Harmonization guidelines in order to determine the camphor content of the volatile oil, which was accurate, precise, robust and selective. The method was validated for specificity, accuracy (100.2%), repeatability and intermediate precision, linearity (r2 > 0.999), limit of detection (2.055 µg/mL), limit of quantification (6.228 µg/mL) and robustness. The common range of accuracy and linearity was between 0.125 and 1.000 mg/mL. Steam distillation was carried out in order to study the essential oil yield of three different T. parthenium L. samples originating from Hungarian medicinal herb collections. The camphor content of the essential oils from the aerial parts of feverfew samples from different origin was compared. Although the composition of the essential oil is well reported, a validated quantitative UHPSFC method for the determination of the constituents is presented herein for the first time.


Assuntos
Cânfora/análise , Cromatografia Líquida/métodos , Óleos Voláteis/química , Tanacetum parthenium/química , Limite de Detecção , Reprodutibilidade dos Testes
20.
Nat Prod Res ; 30(20): 2372-7, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27104751

RESUMO

UPLC-DAD method was developed and validated for the quantitative determination of free flavonol aglycones (kaempferol, quercetin and myricetin) after acidic hydrolysis in six Lysimachia species. Quantitative analyses showed that the amounts of various flavonol aglycones were significantly different in Lysimachia vulgaris, Lysimachia nummularia, Lysimachia punctata, Lysimachia christinae, Lysimachia ciliata and Lysimachia clethroides. The L. clethroides sample was found to be the richest in kaempferol (25.77 ± 1.29 µg/mg extract) and quercetin (97.67 ± 4.61 µg/mg extract), while the L. nummularia sample contained the highest amount of myricetin (20.79 ± 1.00 µg/mg extract). The antioxidant capacity of hydrolysed extracts was evaluated using in vitro DPPH(•) (2,2-diphenyl-1-picrylhydrazyl) and ABTS(•+) [2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid)] decolourisation tests. The observed radical scavenging capacities of the extracts showed a relationship with the measured flavonol aglycone content and composition. The acidic treatment resulted in an increased free radical scavenging activity compared to the untreated methanol extract.


Assuntos
Flavonóis/análise , Primulaceae/química , Antioxidantes/análise , Antioxidantes/química , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Flavonóis/química , Sequestradores de Radicais Livres/análise , Quempferóis/análise , Extratos Vegetais/química , Quercetina/análise
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