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1.
Chem Biodivers ; 21(6): e202400159, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38563619

RESUMEN

While the flowers of Matricaria recutita L., German chamomile, are widely used for medicinal and cosmetic purposes, little is known about its roots, which are used in complementary medicine for the preparation of aqueous fermented extracts for the treatment of cramps and anxiety. To broaden the understanding of the active principles involved, a model fermentation approach was developed and fermentates were compared to commercially manufactured tinctures. Coumarins and hydroxycinnamates were among the major secondary metabolites characterized using HPLC-MSn. After six months of fermentation and storage, low-molecular organic acids were detected by GC-MS. Fermentation contributed to the stabilization of antioxidant and radical scavenging activities, which were in a range of about 8-10 mg gallic acid equivalents/g dry weight and 20-24 mg trolox equivalents/g dry weight, determined by Folin-Ciocalteu and DPPH assays, respectively. In addition, antibacterial activities of the extracts against Gram-positive and -negative bacteria increased during the first week of fermentation. Fermentates were neither cytotoxic nor pro- or anti-inflammatory. Thus, fermentation of chamomile roots is a suitable method for the safe production of biofunctional aqueous chamomile root extracts that remain stable without the addition of synthetic preservatives.


Asunto(s)
Antioxidantes , Fermentación , Matricaria , Fitoquímicos , Extractos Vegetales , Raíces de Plantas , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Matricaria/química , Matricaria/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/aislamiento & purificación , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/metabolismo , Fitoquímicos/química , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Fitoquímicos/metabolismo , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Agua/química , Animales , Picratos/antagonistas & inhibidores , Compuestos de Bifenilo/antagonistas & inhibidores , Supervivencia Celular/efectos de los fármacos
2.
Molecules ; 29(12)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38930889

RESUMEN

The Equisetaceae family, commonly known as horsetails, has been of scientific interest for decades due to its status as one of the most ancient extant vascular plant families. Notably, the corresponding species have found their place in traditional medicine, offering a wide array of applications. This study presents a comprehensive phytochemical analysis of polar secondary metabolites within the sterile stems of five distinct Equisetum species using HPLC-DAD-ESI-MSn. For this purpose, fresh plant material was extracted with acetone/water, and the resulting crude extracts were fractionated using dichloromethane, ethyl acetate, and n-butanol, respectively. The results reveal a complex array of compounds, including hydroxycinnamic acids, hydroxybenzoic acids, flavonoids, and other phenolic compounds. In addition, total phenolic contents (Folin-Ciocalteu assay) and antioxidant activities (DPPH assay) of the plant extracts were evaluated using spectrophotometric methods. The present comparative analysis across the five species highlights both shared and species-specific metabolites, providing valuable insights into their chemical diversity and potential pharmacological properties.


Asunto(s)
Antioxidantes , Equisetum , Fitoquímicos , Extractos Vegetales , Tallos de la Planta , Antioxidantes/química , Antioxidantes/farmacología , Fitoquímicos/química , Extractos Vegetales/química , Equisetum/química , Tallos de la Planta/química , Cromatografía Líquida de Alta Presión , Fenoles/química , Fenoles/análisis , Flavonoides/química , Flavonoides/análisis
3.
Chem Biodivers ; 19(2): e202100850, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34882948

RESUMEN

Preparations derived from roots and rhizomes of Geum urbanum L. are traditionally used for the treatment of ulcers and irritations of mucous membranes of the mouth, stomach, and intestinal tract. In complementary medicine, fermentation is one of the methods applied to recover plant extracts used for the production of such pharmaceutical preparations. The present study was performed to characterize the secondary metabolites and to evaluate the antimicrobial potential of different G. urbanum root and rhizome extracts. For this purpose, individual metabolites of fresh and fermented G. urbanum root and rhizome extracts were analyzed by HPLC-DAD-MSn and GC/MS. Among others, rare ellagitannin-sulfates could be characterized by LC/MSn . In addition, the antibacterial activity of various extracts of fresh and dried G. urbanum roots and rhizomes against Staphylococcus aureus (ATCC 6538) and Cutibacterium acnes (CP033842.1; FDAARGOS 503 chromosome) were assessed and compared to that of G. rivale. Furthermore, low- and high-molecular tannins were fractionated by column chromatography, demonstrating the latter to exhibit highest antibacterial activity.


Asunto(s)
Geum , Antibacterianos/farmacología , Cromatografía Líquida de Alta Presión , Geum/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Taninos/análisis
4.
Molecules ; 27(23)2022 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36500602

RESUMEN

Matricaria recutita L., German chamomile, is one of the most widely used medicinal plants, whose efficacy has been proven in numerous studies. However, its roots have attracted only little interest so far, since mainly above-ground plant parts are used for medicinal purposes. To broaden the knowledge of chamomile roots, a profound phytochemical characterization was performed along with a bioactivity screening of corresponding root extracts. While volatile constituents such as chamomillol and polyynes were detected using GC-MS, HPLC-MSn analyses revealed the occurrence of four coumarin glycosides, more than ten phenolic acid esters and five glyceroglycolipids. Furthermore, the antioxidant activity of the extracts was evaluated. Polar extracts revealed IC50 values ranging from 13 to 57 µg/mL in the DPPH radical scavenging assay, which is in the same range as reported for chamomile flower extracts. In addition, superoxide radical scavenging potential and mild antibacterial effects against S. aureus und B. subtilis were demonstrated. Moreover, to assess interspecies variation in chamomile roots, extracts of M. recutita were compared to those of M. discoidea DC. Interestingly, the latter revealed stronger antioxidant activity. The presented results aim at the valorization of chamomile roots, previously discarded as by-product of chamomile flower production, as a sustainable source of bioactive phytochemicals.


Asunto(s)
Matricaria , Aceites Volátiles , Matricaria/química , Antioxidantes/farmacología , Staphylococcus aureus , Aceites Volátiles/química , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Extractos Vegetales/química
5.
Molecules ; 26(6)2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33799635

RESUMEN

In the present study, Achillea atrata L. and A. millefolium L. were compared for the first time with regard to their phenolic compound profile and antioxidant activity by applying the 2,2-diphenyl-picryl hydrazyl radical assay. For this purpose, aerial plant parts were consecutively extracted with solvents of increasing polarity (dichloromethane, n-butanol, ethyl acetate), revealing that the A. atrata ethyl acetate fraction showed the highest antioxidant activity with an IC50 value of 12.2 ± 0.29 µg/mL compared to 17.0 ± 0.26 µg/mL for A. millefolium. Both species revealed the presence of luteolin, apigenin, centaureidin, and nevadensin exclusively in this most polar fraction, which are known as effective 2,2-diphenyl-picryl hydrazyl radical scavengers. The antioxidant capacity of the aforementioned fractions strikingly correlated with their total phenolic contents, which was highest in the ethyl acetate fraction of A. atrata. Characterization of the metabolite profiles of both Achillea species showed only marginal differences in the presence of key compounds, whereas the concentrations of individual compounds appeared to be species-specific. Our results suggest that A. atrata, based on its compound pattern and bioactivity characteristics, has similar qualities for phytotherapy as A. millefolium.


Asunto(s)
Achillea/química , Achillea/metabolismo , Fenoles/análisis , Antioxidantes/química , Apigenina , Flavonas , Flavonoides , Luteolina , Fenoles/química , Componentes Aéreos de las Plantas/química , Extractos Vegetales/química , Solventes
6.
Chem Biodivers ; 17(4): e1900724, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32096590

RESUMEN

The investigations reported here focus on an in-depth characterization of the secondary metabolite profile of Sanguisorba officinalis flowers. For this purpose, fresh flowers were extracted with MeOH/H2 O and EtOH/H2 O and the resulting crude extracts fractionated using CH2 Cl2 , AcOEt, and BuOH. Individual compounds were characterized by high performance liquid chromatography and gas chromatography coupled with mass spectrometric detection (HPLC-DAD-MSn and GC/MS). MeOH/H2 O extraction and LC/MSn investigations revealed the occurrence of flavonoid glycosides (quercetin, kaempferol), ellagitannin glycosides and four anthocyanins. Among the latter, two components, i. e., cyanidin-malonyl-glucose and cyanidin-galloyl-hexose, have not been reported for S. officinalis so far. Furthermore, phenylethylamine was characterized for the first time in Sanguisorba by pH value dependent extraction with CH2 Cl2 . In addition, AcOEt and BuOH extracts were analyzed by GC/MS both prior to and after acid hydrolysis of secondary metabolites. For this purpose, the extracts were treated with 1 n HCl solution (105 °C, 1 h) and derivatized with BSTFA. Analyses revealed the occurrence of several classes of phenolic compounds, such as gallic acid, hydroxybenzoic acid, hydroxycinnamic acid and ellagic acid derivatives. Additionally, the most prominent ursane-type triterpenoid (ziyu-glycoside I) from Sanguisorba and its corresponding aglycone isomers were detected and assigned based on their characteristic fragmentation patterns.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Sanguisorba/química , Espectrometría de Masas en Tándem , Aminas/análisis , Aminas/química , Aminas/metabolismo , Antocianinas/análisis , Antocianinas/química , Antocianinas/metabolismo , Cromatografía Líquida de Alta Presión , Flores/química , Flores/metabolismo , Glicósidos/análisis , Glicósidos/química , Glicósidos/metabolismo , Isomerismo , Fenoles/análisis , Fenoles/química , Fenoles/metabolismo , Extractos Vegetales/química , Sanguisorba/metabolismo
7.
Chem Biodivers ; 17(10): e2000485, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32860459

RESUMEN

Extracts of kidney vetch (Anthyllis vulneraria L.) are becoming increasingly interesting as ingredients for the health and cosmetics industry. However, comprehensive phytochemical investigations of this plant are scant in the literature. Thus, the aim of the present work was an in-depth characterization of semi-polar constituents from A. vulneraria. To capture a broad spectrum of compounds, the aerial parts of A. vulneraria were extracted with EtOH/water and the resulting crude extracts fractionated by partition between AcOEt and BuOH. Secondary plant metabolites were analyzed by HPLC-ESI-MSn and GC/MS. In a fraction obtained from the BuOH extract via Amberlite® XAD-7 purification glycosides of kaempferol, quercetin, isorhamnetin and rhamnocitrin were detected by LC/MSn , besides flavonoids acylated with meglutol (3-hydroxy-3-methylglutaric acid), acetic and ferulic acids. Moreover, aglycons were analyzed in extracts after 1 N HCl hydrolysis and derivatization with BSTFA. GC/MS analysis of the hydrolysates revealed the incidence of compounds like meglutol, OH/OMe-substituted benzoic acids, ferulic and fatty acids, flavonoids, sugars and the triterpenoid medicagenic acid. Furthermore, a hemolytic activity was detected in the AcOEt extract using a blood-agar assay, and this was ascribed to the occurrence of saponins. In a saponin fraction, obtained from the AcOEt extract by chromatographic purification, two main saponins were characterized by LC/MSn and HR-ESI-MSn . A pure sapogenin could be isolated via VLC and CC purification upon acid hydrolysis of the saponins and assigned to saikogenin D by NMR analysis.


Asunto(s)
Fabaceae/química , Fitoquímicos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Medicina de Hierbas , Estructura Molecular , Fitoquímicos/química , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray
8.
BMC Complement Altern Med ; 19(1): 105, 2019 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-31113420

RESUMEN

BACKGROUND: The therapeutic use of Helleborus niger L. is manifold due to its specific phytochemical composition. Two compound groups, the ranunculin derivates including protoanemonin and the steroidal saponins, are also associated with toxicity (genotoxicity, disintegration of membrane structures). Therefore, in vitro investigations were performed on safety aspects of a Helleborus niger aqueous fermented extract (HNE). In addition its therapeutic potential against various cancer cell lines was assessed to gain insight into the respective mechanisms of action. METHODS: To evaluate the safe use of HNE, Ames and hemolytic tests were carried out. Two angiogenesis assays in 2D and 3D design were conducted to assess the anti-angiogenetic potential, for which human umbilical vein endothelial cells (HUVEC) were chosen. A panel of tumor cell lines was used in 2D and 3D proliferation assays as well in the migration- and invasion-assay. All investigations were performed with HNE compared to reference substances. The 2D proliferation assay was additionally performed with isolated compounds of HNE (characteristic steroidal saponins). RESULTS: HNE did not exhibit any genotoxic potential. Concentrations up to 10 µl/ml were classified as non-hemolytic. HNE exerted anti-angiogenetic effects in HUVEC and anti-proliferative effects in five cancer cell lines, whereas hellebosaponin A and D as well macranthosid I did not show comparable effects neither singly nor in combination. Due to the inherent instability of protoanemonin in isolated form, parallel investigations with protoanemonin could not be performed. HNE (600-1000 µg/ml) inhibited the migration of certain cancer cells by > 80% such as Caki-2, DLD-1 and SK-N-SH. CONCLUSION: HNE exhibit neither genotoxic nor hemolytic potential. The present investigations verify the anti-angiogenetic effects on HUVEC, the anti-proliferative effects and migration-inhibiting properties on tumor cells. The lower effect of the relevant steroidal saponins compared to the whole extract underlines the fact that the latter is more effective than a blend of isolated pharmacologically active components.


Asunto(s)
Antineoplásicos , Helleborus/química , Extractos Vegetales , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/toxicidad , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/toxicidad , Saponinas
9.
Chem Biodivers ; 15(5): e1800035, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29575712

RESUMEN

Seeds from Hypericum species have recently been identified as an interesting source of xanthone derivatives. Extraction of seeds from H. perforatum with MeOH and subsequent concentration via polyamide adsorption yielded a fraction enriched in tetrahydroxyxanthones (THX), which were further semipurified by silica gel chromatography. Based on tentative structure assignment of the two main THX X1 and X2 by NMR a total synthesis was performed for both compounds (THX 1 and 2, respectively), starting with an Ullmann ether synthesis. The synthesized 1 and 2 were characterized via 1D- and 2D-NMR methods as well as by LC/HR-MS analysis and proven to be 1,4,6,7-THX (1) and 1,2,6,7-THX (2). Final structure assignment of the natural Hypericum THX constituents was accomplished by comparing chromatographic and spectroscopic data (LC/MSn and GC/MS) with those of 1 and 2 which were obtained by synthesis. Beyond, investigations into the seeds of H. perforatum and H. tetrapterum by scanning electron microscopy (SEM) provided insights of the structure of the testa (seed coat), which is established by two cell layers, with the lignified sclerenchyma presumably being the depository of the xanthones.


Asunto(s)
Hypericum/química , Xantonas/química , Estructura Molecular , Extractos Vegetales/química , Semillas/química , Xantonas/síntesis química , Xantonas/aislamiento & purificación
10.
Chem Biodivers ; 14(2)2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28134470

RESUMEN

Mercurialis tomentosa L. has been used in Spanish ethnomedicine. In the present study the first phytochemical characterisation of a lipid fraction from M. tomentosa was performed. The CHCl3 extraction of aerial parts from M. tomentosa and GC/MS investigations revealed the occurrence of cuticular lipid and wax constituents, like long chain n-alcohols and n-aldehydes (C22  - C30 ), besides several aromatic constituents, i.e., phenylpropanoids and n-alkylresorcinols. The latter were further purified by CC and analysed by LC/MSn . In contrast to other Mercurialis species, i.e., M. annua, M. perennis, which exclusively contain 5-n-alkylresorcinols (1a - j, Cn ), mainly 5-n-alkyl-2-methylresorcinols (2a - j, Cn *) with side chain lengths of C15  - C25 were found in M. tomentosa, in addition to 1a - j. Thus, the latter compounds may be utilised for analytical characterisation and authentication of M. tomentosa based on fingerprinting methods. For structure elucidation a novel facile total synthesis of one representative 5-n-alkyl-2-methylresorcinol homologue (2d, C19 *) was developed, starting with a Grignard reaction from a substituted benzoic acid chloride (19). The compound obtained by synthesis was identical to the natural product 2d in terms of its chromatographic and spectroscopic features. Futhermore, 2d exhibited satisfactory DPPH free radical scavenging activity (IC50  = 37.8 µm) when compared to trolox (IC50  = 21.0 µm), corroborating the antioxidant features of these amphipathic molecules.


Asunto(s)
Antioxidantes/farmacología , Euphorbiaceae/química , Lípidos/análisis , Extractos Vegetales/análisis , Resorcinoles/análisis , Cromatografía de Gases y Espectrometría de Masas , Lípidos/química , Extractos Vegetales/química , Resorcinoles/química , España
11.
Chem Biodivers ; 14(8)2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28557380

RESUMEN

Seeds of Hypericum perforatum and H. tetrapterum were extracted with dichloromethane and methanol and investigated by chromatographic and mass spectrometric methods. Both species yielded a fatty oil fraction amounting to 30.5% and 18.0% of the seed weight, respectively. Linoleic acid (C18:2n-6) was shown to be the predominant fatty acid constituent. Moreover, xanthone derivatives, i.e. tetrahydroxyxanthones (THX), xanthone-glycosides and xanthone-sulfonates, were assigned in methanolic extracts. For structure elucidation, one representative xanthone, namely 1,3,6,7-THX, was synthesized and analyzed via HPLC-DAD/MSn and GC/MS. Total THX contents were quantitated applying a validated HPLC-DAD method, resulting in 1.25 g/kg (H. perforatum) and 0.27 g/kg (H. tetrapterum), respectively. Moreover, the free radical scavenging capacity of the methanol extracts was tested using the DPPH antioxidant assay. Both, H. perforatum (IC50 = 8.7 mg/l) and 1,3,6,7-THX (IC50 = 3.0 mg/l), exhibited good DPPH free radical scavenging activity compared to Trolox (IC50 = 6.6 mg/l).


Asunto(s)
Hypericum/química , Lípidos/química , Lípidos/farmacología , Fenoles/química , Fenoles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Hypericum/metabolismo , Lípidos/análisis , Espectroscopía de Resonancia Magnética , Oxidación-Reducción/efectos de los fármacos , Fenoles/análisis , Semillas/química , Semillas/metabolismo , Espectrometría de Masa por Ionización de Electrospray , Xantonas/análisis , Xantonas/química , Xantonas/farmacología
12.
Int J Mol Sci ; 18(1)2017 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-28098796

RESUMEN

Primula veris L. is an important medicinal plant with documented use for the treatment of gout, headache and migraine reaching back to the Middle Ages. Triterpenoid saponins from roots and flowers are used in up-to-date phytotherapeutic treatment of bronchitis and colds due to their expectorant and secretolytic effects. In addition to the wild type plants with yellow petals, a red variant and an intermediate orange form of Primula veris L. have recently been found in a natural habitat. The secondary metabolite profiles of roots, leaves and flowers of these rare variants were investigated and compared with the wild type metabolome. Two flavonoids, six flavonoid glycosides, four novel methylated flavonoid glycosides, five anthocyanins and three triterpenoid saponins were identified in alcoholic extracts from the petals, leaves and roots of the three variants by high performance liquid chromatography (HPLC)-diode array detection (DAD)/mass spectrometry (MSn) analyses. Anthocyanins were detected in the petals of the red and orange variety, but not in the wild type. No other effects on the metabolite profiles of the three varieties have been observed. The possibility is discussed that a regulatory step of the anthocyanin biosynthetic pathway may have been affected by mutation thus triggering color polymorphism in the petals.


Asunto(s)
Flavonoides/metabolismo , Flores/metabolismo , Metabolómica/métodos , Mutación/genética , Pigmentación/genética , Primula/metabolismo , Saponinas/metabolismo , Triterpenos/metabolismo , Cromatografía Líquida de Alta Presión , Espectrometría de Masas , Metaboloma , Fitoquímicos/análisis , Metabolismo Secundario , Espectrofotometría Ultravioleta
13.
Chem Biodivers ; 13(5): 602-12, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27039891

RESUMEN

Five homologous acetylated acylglycerols of 3-hydroxyfatty acids (chain lengths C(14) - C(18)), named euphrasianins A - E, were characterized for the first time in Euphrasia rostkoviana Hayne (Orobanchaceae) by gas chromatography/mass spectrometry (GC/MS) and high-performance liquid chromatography/atmospheric pressure chemical ionization-mass spectrometry (HPLC/APCI-MS(n) ). In addition to mass spectrometric data, structures of euphrasianins were verified via a three-step total synthesis of one representative homologue (euphrasianin A). The structure of the latter was confirmed by 1D- and 2D-NMR experiments as well as high-resolution electrospray ionization-mass spectrometry (HR-ESI-MS). The absolute configuration of the 3-hydroxyfatty acid moiety at C(3) was found to be R in the natural euphrasianins, which was determined by alkaline hydrolysis and methylation of a purified fraction, followed by chiral GC analysis. Furthermore, in extracts of Euphrasia tetraquetra (Bréb.) Arrond. euphrasianins C and E were detected exclusively, indicating that this subclass of lipid constituents is possibly valuable for fingerprinting methods.


Asunto(s)
Euphrasia/química , Glicerol/análogos & derivados , Glicerol/aislamiento & purificación , Lípidos/aislamiento & purificación , Orobanchaceae/química , Extractos Vegetales/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Glicerol/química , Lípidos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray
14.
Z Naturforsch C J Biosci ; 71(3-4): 55-64, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26974139

RESUMEN

The seeds of Strophanthus kombé Oliv. are known to contain high levels of cardioactive compounds. However, the therapeutic use of Strophanthus in the treatment of cardiopathy requires more detailed knowledge of the compound profile to profit from the full potential of Strophanthus preparations. Therefore, the objective was to characterize the cardenolide profile and lipophilic constituents in S. kombé seeds using methods applicable in routine quality control. Freshly prepared S. kombé seed extracts were analyzed without previous sample clean-up using a novel HPLC-DAD-MSn method. In addition, seed oils were analyzed by GC-MS following derivatization of the lipids. More than 20 cardenolides were tentatively assigned in the seed extracts including strophanthidin, strophanthidol, periplogenin and strophanthidinic acid aglycones, carrying various saccharide moieties. The findings revealed the presence of eight novel cardenolides, which have not been described for S. kombé so far. The occurrence of strophanthidinic acid derivatives was verified by comparison with synthesized strophanthidinic acid-cymaropyranoside. GC-MS characterization of the oils mainly revealed the presence of fatty acids, especially oleic acid and linoleic acid, as well as phytosterols, the latter representing intermediates of cardenolide biosynthesis. In summary, these findings broaden our knowledge on the secondary metabolism of Strophanthus.


Asunto(s)
Glicósidos Cardíacos/análisis , Lípidos/análisis , Semillas/química , Strophanthus/química , Cromatografía Líquida de Alta Presión , Digitoxigenina/análogos & derivados , Digitoxigenina/análisis , Ácidos Grasos/análisis , Cromatografía de Gases y Espectrometría de Masas , Ácido Linoleico/análisis , Espectrometría de Masas , Estructura Molecular , Ácido Oléico/análisis , Fitosteroles/análisis , Extractos Vegetales/química , Estrofantidina/análisis
15.
Chem Res Toxicol ; 27(4): 611-26, 2014 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-24547959

RESUMEN

Oxidative stress has been proposed to be an important factor in the pathogenesis of Alzheimer's disease (AD), playing a central role in amyloid ß-protein (Aß) generation and neuronal apoptosis. Oxidative damage directly correlates with the presence of Aß deposits. Aß and oxidative stress jointly induce neuronal death, Aß deposits, gliosis, and memory impairment in AD. In order to counteract AD neurodegeneration, the inhibition of the vicious cycle of Aß generation and oxidation is an attractive therapeutic strategy, and antiamyloidogenic and antioxidant herbal drugs could represent an alternative and valid approach. In this context, an alcoholic extract from Laurus nobilis leaves (LnM) and seven fractions obtained therefrom were of interest. All extracts prepared through extractive and chromatographic techniques were phytochemically studied by chromatographic techniques including gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS(n)). The potential antioxidant efficacy of the obtained fractions was screened by DPPH(•) and ABTS(•+) assays, as well as specific assay media characterized from the presence of highly reactive ROS and RNS species (ROO(•), OH(•), O2(•-), and NO). In order to evaluate the preparation of safe and nontoxic extracts, MTT, SRB, and LDH assays toward SH-5YSY and SK-N-BE(2)-C human neuronal cell lines, as well as on C6 mouse glial cell line, were performed. The apoptosis-inducing properties by spectroscopic evaluation of the extracts' ability to activate caspase-3 and by a DNA fragmentation assay were also investigated. Data thus obtained allowed us to state the absence of toxic effects induced by phenolic-rich fractions (LnM, LnM-1, LnM-1a, LnM-1b, and LnM-2c), which at the same time exerted significant cytoprotective and antioxidant responses in hydrogen peroxide and Aß(25-35)-fragment-oxidized cell systems. The potential antiamyloidogenic efficacy of Laurus nobilis leaf polar extracts in the Aß(25-35) fragment oxidized cell systems was further analyzed by Congo red staining.


Asunto(s)
Antioxidantes/farmacología , Laurus/química , Fármacos Neuroprotectores/farmacología , Extractos Vegetales/farmacología , Hojas de la Planta/química , Polifenoles/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Humanos , Especies Reactivas de Oxígeno/metabolismo , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
16.
Rapid Commun Mass Spectrom ; 28(16): 1801-12, 2014 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-25559450

RESUMEN

RATIONALE: Isolation and extensive nuclear magnetic resonance (NMR) analyses revealed polyhydroxy steroid saponins to be characteristic constituents in Helleborus niger L. roots. A comprehensive study including various multi-stage mass spectrometry (MS(n) ) experiments provided first solid chromatographic and mass spectrometric information facilitating future analysis and structural assessment of polyhydroxy saponins by LC/MS(n) techniques without isolation and NMR analyses. METHODS: The polyhydroxy saponins were analyzed by direct syringe injection or chromatographically separated on a capillary high-performance liquid chromatography (HPLC) system coupled to an electrospray ionization (ESI) source. MS(n) spectra were recorded on an ion trap mass spectrometer including up to four fragmentation stages (LC/ESI-MS/MS). Additionally, high-resolution mass spectra were recorded on an Orbitrap Fourier transform (FT) mass spectrometer equipped with a nanospray-ESI interface. RESULTS: The polyhydroxy hellebosaponins A and D were discovered to be significant constituents from H. niger roots. Extensive study of their MS(n) data revealed that they readily fragmented in the positive ion mode providing diagnostic fragments for elucidation of the steroidal character and number of OH groups. The negative ion mode yielded valuable information on the [M-H](-) ion, number and location of acetyl groups and sugar units. Additionally, fragmentation pathways for positive and negative ion modes were proposed. CONCLUSIONS: These results not only extend the knowledge about H. niger saponins, but also provide a facilitated approach to the analysis of polyhydroxy saponins by LC/MS(n) without prior isolation and extensive NMR identification. Additionally, proposed fragmentation pathways for positive and negative ionization modes provide a solid complementary database for further, more detailed MS(n) studies.


Asunto(s)
Helleborus/química , Raíces de Plantas/química , Saponinas/análisis , Saponinas/química , Espectrometría de Masas en Tándem/métodos , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Extractos Vegetales/química
17.
Anal Bioanal Chem ; 406(24): 6035-50, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25027721

RESUMEN

Mediterranean sea squill (Drimia maritima (L.) Stearn) is used in the production of medicinal products. Current HPLC methods comprise tedious sample clean-up and have been merely focused on the analysis of cardiac glycosides, whereas a thorough characterization of D. maritima considering both the latter compound class and more hydrophilic secondary metabolites in one HPLC run has not been performed so far. Consequently, a novel HPLC-DAD-MS(n) method has been developed allowing the simultaneous determination of both cardiac glycosides and phenolic compounds, which is characterized by simplified sample preparation. This method was applied to characterize sea squill, revealing a complex profile of its extractive compounds derived from the two classes. Furthermore, the potential of the method reported here to quantitate the predominant compounds, i.e., dihydroquercetin derivatives and bufadienolides, was demonstrated. The occurrence of phenolic compounds, not described for sea squill so far, and of characteristic compounds specific to individual plant parts or vegetation stages was further addressed. The data revealed that classification of various vegetation phases based on quantitative evaluation of bufadienolides and dihydroquercetin derivatives applying principal component analysis (PCA) appears possible. Thus, the methodology presented here forms the basis for future routine application in quality control of raw materials and pharmaceutical preparations derived from sea squill. This will allow systematic comparison of different plant parts, vegetation stages and origins based on an extended sample set.


Asunto(s)
Bufanólidos/química , Cromatografía Líquida de Alta Presión/métodos , Liliaceae/química , Liliaceae/crecimiento & desarrollo , Espectrometría de Masas/métodos , Fenoles/química , Extractos Vegetales/química , Liliaceae/clasificación
18.
Chem Biodivers ; 11(2): 276-98, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24591317

RESUMEN

The aerial parts of the medicinal plant Helleborus niger L. comprise a substantial number of constituents with only few of them identified so far. To expand the knowledge of its secondary metabolite profile, extracts from H. niger leaves and stems were investigated by liquid chromatography/tandem mass spectrometry (LC/MS(n) ). Specific identification strategies using LC/MS are established and discussed in detail. The leaves turned out to contain acylated and non-acylated quercetin and kaempferol oligoglycosides, protoanemonin and its precursor ranunculin, ß-ecdysone, and a variety of steroidal saponins, mainly in the furostanol form. The sapogenins were elucidated as of sarsasapogenyl, diosgenyl, and macranthogenyl structures, and confirmed by comparison with the respective reference compounds. The secondary metabolite profiles were almost identical in both plant parts except that the stems lacked kaempferol derivatives and some saponins. The ranunculin derivatives and ß-ecdysone were found in both plant parts. Correlations between the location of the compound groups and the plant's defense strategies are proposed. Additionally, the role of the detected secondary metabolites as protective substances against exogenic stress and as a defense against herbivores is discussed.


Asunto(s)
Helleborus/química , Fenoles/química , Saponinas/química , Cromatografía Liquida , Fenoles/aislamiento & purificación , Hojas de la Planta/química , Tallos de la Planta/química , Saponinas/aislamiento & purificación , Espectrometría de Masas en Tándem
19.
Chem Biodivers ; 10(9): 1706-23, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24078603

RESUMEN

Dog's mercury (Mercurialis perennis L.) is an old medicinal plant, nowadays used in complementary medicine. Aqueous fermented extracts of the plant are being mainly applied in remedies to treat external inflammations, but a thorough phytochemical characterization is still lacking. Therefore, the conversion of characteristic compound classes from M. perennis extracts during fermentation and storage was investigated. The microbial transformation of the two main depsides phaselic acid (=(2R)-O-[(E)-caffeoyl]malic acid; 1) and mercurialis acid (=(2R)-[(E)-caffeoyloxy]glutaric acid; 2) was monitored by HPLC-DAD. The degradation followed a second-order kinetic, and the calculated half-life periods of both constituents were 67 and 30 months, respectively. Several depside metabolites were detected by GC/MS in AcOEt extracts as (t) BuMe2 Si (TBDMS) derivatives after derivatization, mainly dihydrocinnamic acids. Moreover, numerous α-hydroxy acids were found, allegedly as degradation products from amino acids or peptides. The microbial alteration of the main alkaloid hermidin was also examined. After three days of fermentation, three novel N-metabolites were formed and thoroughly assigned in CH2 Cl2 extracts as a mixture of 3-ethylhermidin, 3-ethylhermidin quinone, and (E/Z)-3-ethylidenehermidin by GC/MS and NMR methods, as well as by means of total synthesis. A mechanism for the formation of these N-metabolites starting from dimeric hermidin oxidation products is proposed. The obtained results reveal the complex pathways plant constituents may undergo during the fermentation of the extracts.


Asunto(s)
Alcaloides/química , Depsidos/química , Euphorbiaceae/química , Alcaloides/metabolismo , Cromatografía Líquida de Alta Presión , Depsidos/metabolismo , Euphorbiaceae/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Semivida , Cinética , Conformación Molecular , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Plantas Medicinales/química , Plantas Medicinales/metabolismo , Piridonas/síntesis química , Piridonas/química , Estereoisomerismo , Agua/química
20.
Z Naturforsch C J Biosci ; 68(1-2): 529-40, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23687690

RESUMEN

Acetone/water extracts from the leaves, including stalks, of Alchemilla vulgaris L. and A. mollis (Buser) Rothm. were investigated for their phenolic composition by liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 24 and 27 compounds were detected for A. vulgaris and A. mollis, respectively. Pedunculagin and agrimoniin, as described in earlier reports for A. vulgaris, as well as other monomeric and oligomeric ellagitannins such as sanguiin H-10, castalagin/vescalagin, and galloyl-bis-hexahydroxydiphenoyl (HHDP) hexose constituted the major phenolic fraction of both plant species. Also, gallic and chlorogenic acids were found in both extracts. Interestingly, catechin and a procyanidin trimer were detected only in A. mollis. The flavonoid fraction comprised quercetin glucuronide as major compound in addition to several other quercetin glycosides. Most interestingly, a tentatively identified kaempferol glucuronide and a methylated quercetin glucuronide were exclusively found in A. mollis. Finally, the overall phenolic fingerprints of both Alchemilla species, harvested in May and August, i.e. at the beginning and the end of the flowering period, were compared. A general accumulation of phenolic constituents was observed later in the year, especially with regard to the ellagitannins.


Asunto(s)
Alchemilla/química , Fenoles/aislamiento & purificación , Cromatografía Liquida , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem
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