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1.
PLoS Comput Biol ; 14(3): e1006018, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29494588

RESUMO

Nuclear Magnetic Resonance (NMR) spectroscopy is, together with liquid chromatography-mass spectrometry (LC-MS), the most established platform to perform metabolomics. In contrast to LC-MS however, NMR data is predominantly being processed with commercial software. Meanwhile its data processing remains tedious and dependent on user interventions. As a follow-up to speaq, a previously released workflow for NMR spectral alignment and quantitation, we present speaq 2.0. This completely revised framework to automatically analyze 1D NMR spectra uses wavelets to efficiently summarize the raw spectra with minimal information loss or user interaction. The tool offers a fast and easy workflow that starts with the common approach of peak-picking, followed by grouping, thus avoiding the binning step. This yields a matrix consisting of features, samples and peak values that can be conveniently processed either by using included multivariate statistical functions or by using many other recently developed methods for NMR data analysis. speaq 2.0 facilitates robust and high-throughput metabolomics based on 1D NMR but is also compatible with other NMR frameworks or complementary LC-MS workflows. The methods are benchmarked using a simulated dataset and two publicly available datasets. speaq 2.0 is distributed through the existing speaq R package to provide a complete solution for NMR data processing. The package and the code for the presented case studies are freely available on CRAN (https://cran.r-project.org/package=speaq) and GitHub (https://github.com/beirnaert/speaq).


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Algoritmos , Cromatografia Líquida/métodos , Imageamento por Ressonância Magnética/métodos , Software , Fluxo de Trabalho
2.
J Nat Prod ; 80(4): 1187-1191, 2017 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-28211687

RESUMO

Four new colchicinoids were isolated from the seeds of Gloriosa superba together with the known compounds colchicoside (4) and 3-de-O-methylcolchicine-3-O-ß-d-glucopyranosyl-(1→4)-3-O-ß-d-glucopyranoside (6), by means of conventional column chromatography and LC-DAD-SPE-NMR. The new compounds were identified as N-deacetyl-N-formyl-3-de-O-methylcolchicine-3-O-ß-d-glucopyranoside (1), 3-de-O-methylcolchicine-3-O-ß-d-glucopyranosyl-(1→6)-3-O-ß-d-glucopyranoside (2), N-deacetyl-N-formyl-3-de-O-methylcolchicine-3-O-ß-d-glucopyranosyl-(1→6)-3-O-ß-d-glucopyranoside (3), and 3-de-O-methylcolchicine-3-O-ß-d-glucopyranosyl-(1→3)-3-O-ß-d-glucopyranoside (5). The structure elucidation was performed by means of NMR (COSY, HSQC, and HMBC), HRESIMS/MS, and GCMS data analysis.


Assuntos
Colchicaceae , Colchicina , Glicosídeos , Saponinas , Sementes , Colchicaceae/química , Colchicina/análogos & derivados , Colchicina/química , Colchicina/isolamento & purificação , Glicosídeos/química , Glicosídeos/isolamento & purificação , Índia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Saponinas/química , Saponinas/isolamento & purificação , Sementes/química
3.
Planta Med ; 83(9): 790-796, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28152554

RESUMO

Hymenocardine is a cyclopeptide alkaloid present in the root bark of Hymenocardia acida. In traditional African medicine, the leaves and roots of this plant are used to treat malaria, and moderate in vitro antiplasmodial activity has been reported for hymenocardine. However, in view of its peptide-like nature, potential metabolisation after oral ingestion has to be taken into account when considering in vivo experiments. In this study, the stability and small intestinal absorption of hymenocardine was assessed using an in vitro gastrointestinal dialysis model. In addition, potential liver metabolisation was investigated in vitro by incubation with a human S9 fraction. Moreover, hymenocardine was administered to rats per os, and blood and urine samples were collected until 48 and 24 h after oral administration, respectively. All samples resulting from these three experiments were analyzed by LC-MS. Analysis of the dialysate and retentate, obtained from the gastrointestinal dialysis model, indicated that hymenocardine is absorbed unchanged from the gastrointestinal tract, at least in part. After S9 metabolisation, several metabolites of hymenocardine could be identified, the major ones being formed by the reduction and/or the loss of an N-methyl group. The in vivo study confirmed that hymenocardine is absorbed from the gastrointestinal tract unchanged, since it could be identified in both rat plasma and urine, together with hymenocardinol, its reduction product.


Assuntos
Alcaloides/metabolismo , Embriófitas/química , Absorção Gastrointestinal , Peptídeos Cíclicos/metabolismo , Extratos Vegetais/metabolismo , Alcaloides/sangue , Alcaloides/química , Alcaloides/urina , Animais , Fracionamento Químico , Humanos , Fígado/metabolismo , Masculino , Medicinas Tradicionais Africanas , Estrutura Molecular , Peptídeos Cíclicos/sangue , Peptídeos Cíclicos/química , Peptídeos Cíclicos/urina , Extratos Vegetais/sangue , Extratos Vegetais/química , Extratos Vegetais/urina , Ratos , Ratos Wistar
4.
Pharm Biol ; 55(1): 1500-1512, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28372473

RESUMO

CONTEXT: Several Cecropia (Cecropiaceae) species are traditionally used in Latin America for the treatment of a variety of diseases including diabetes, arterial hypertension, asthma, bronchitis, anxiety, and inflammation. At present, a number of commercial products based on these plants have been introduced into the market with very little information on methods for guaranteeing their quality and safety. OBJECTIVE: This work proposes potential chemical markers for the quality control of the raw materials of Cecropia obtusifolia Bertol., Cecropia peltata L., Cecropia glaziovii Snethl., Cecropia pachystachya Trécul, and Cecropia hololeuca Miq. METHODS: The Herbal Chemical Marker Ranking System (Herb MaRS) developed by the National Institute of Complementary Medicine (NICM) at the University of Western Sydney was used for selecting chemical markers for the quality control of selected medicinal species of Cecropia. This review covers the period from 1982 to 2016. RESULTS: Chlorogenic acid, flavonoidal glycosides (orientin, isoorientin, vitexin, isovitexin, and rutin), catechin, epicatechin, procyanidins (B2, B5, and C1), steroids (ß-sitosterol), and triterpenoids (α-amyrin, pomolic, tormentic and ursolic acids) were selected as chemical markers for the quality control of the leaves. CONCLUSION: It is necessary to establish comprehensive standards for guaranteeing quality, safety and efficacy of herbal drugs. The selection of adequate chemical markers for quality control purposes requires a good knowledge about the chemical composition of medicinal plants and their associated biological properties. To the best of our knowledge this review article is the first to address the identification and quantitative determination of the chemical markers for the genus Cecropia.


Assuntos
Cecropia/química , Compostos Fitoquímicos/normas , Extratos Vegetais/normas , Controle de Qualidade , Animais , Cecropia/classificação , Humanos , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/uso terapêutico , Fitoterapia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Plantas Medicinais
5.
Anal Bioanal Chem ; 408(6): 1643-56, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26753972

RESUMO

Counterfeit medicines are a global threat to public health. High amounts enter the European market, which is why characterization of these products is a very important issue. In this study, a high-performance liquid chromatography-photodiode array (HPLC-PDA) and high-performance liquid chromatography-mass spectrometry (HPLC-MS) method were developed for the analysis of genuine Viagra®, generic products of Viagra®, and counterfeit samples in order to obtain different types of fingerprints. These data were included in the chemometric data analysis, aiming to test whether PDA and MS are complementary detection techniques. The MS data comprise both MS1 and MS2 fingerprints; the PDA data consist of fingerprints measured at three different wavelengths, i.e., 254, 270, and 290 nm, and all possible combinations of these wavelengths. First, it was verified if both groups of fingerprints can discriminate between genuine, generic, and counterfeit medicines separately; next, it was studied if the obtained results could be ameliorated by combining both fingerprint types. This data analysis showed that MS1 does not provide suitable classification models since several genuines and generics are classified as counterfeits and vice versa. However, when analyzing the MS1_MS2 data in combination with partial least squares-discriminant analysis (PLS-DA), a perfect discrimination was obtained. When only using data measured at 254 nm, good classification models can be obtained by k nearest neighbors (kNN) and soft independent modelling of class analogy (SIMCA), which might be interesting for the characterization of counterfeit drugs in developing countries. However, in general, the combination of PDA and MS data (254 nm_MS1) is preferred due to less classification errors between the genuines/generics and counterfeits compared to PDA and MS data separately.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos Falsificados/análise , Espectrometria de Massas/métodos , Citrato de Sildenafila/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Espectrometria de Massas/instrumentação , Análise de Componente Principal , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador
6.
J Nat Prod ; 79(7): 1746-51, 2016 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-27351950

RESUMO

Four cyclopeptide alkaloids (1-4) were isolated from the root bark of Hymenocardia acida by means of semipreparative HPLC with DAD and ESIMS detection and conventional separation methods. Structure elucidation was performed by spectroscopic means. In addition to the known compound hymenocardine (1), three other alkaloids were isolated for the first time from a natural source. These included a hymenocardine derivative with a hydroxy group instead of a carbonyl group that was named hymenocardinol (2), as well as hymenocardine N-oxide (3) and a new cyclopeptide alkaloid containing an unusual histidine moiety named hymenocardine-H (4). The isolated cyclopeptide alkaloids were tested for their antiplasmodial activity and cytotoxicity. All four compounds showed moderate antiplasmodial activity, with IC50 values ranging from 12.2 to 27.9 µM, the most active one being hymenocardine N-oxide (3), with an IC50 value of 12.2 ± 6.6 µM. Compounds 2-4 were found not to be cytotoxic against MRC-5 cells (IC50 > 64.0 µM), but hymenocardine (1) showed some cytotoxicity, with an IC50 value of 51.1 ± 17.2 µM.


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antimaláricos/isolamento & purificação , Magnoliopsida/química , Peptídeos Cíclicos/isolamento & purificação , Alcaloides/química , Antimaláricos/química , Antimaláricos/farmacologia , Guiné , Concentração Inibidora 50 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Casca de Planta/química , Raízes de Plantas/química , Plasmodium falciparum/efeitos dos fármacos
7.
J Nat Prod ; 79(11): 2865-2872, 2016 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-27933893

RESUMO

Nine cyclopeptide alkaloids (1-9), of which five (compounds 2, 3, 5, 8, and 9) are described herein for the first time, were isolated from roots of Ziziphus oxyphylla by means of conventional separation methods as well as semipreparative HPLC with DAD and ESIMS detection and LC-DAD-SPE-NMR. Structure elucidation was done by spectroscopic means. Nummularine-R (1), a previously known constituent from this species, was isolated along with its new derivatives O-desmethylnummularine-R (2) and O-desmethylnummularine-R N-oxide (3). In addition, the known compounds hemsine-A (4) and ramosine-A (6), as well as hemsine-A N-oxide (5), were isolated. Moreover, oxyphylline-C (7), a known constituent of Z. oxyphylla stems, was obtained, and two new compounds were identified, oxyphyllines-E (8) and -F (9). Just like oxyphylline-C, oxyphyllines-E and -F belong to the relatively rare class of neutral cyclopeptide alkaloids. The antiplasmodial activity and cytotoxicity of compounds 1, 2, 4, 6, and 9 were evaluated, and the most promising activity was found for O-desmethylnummularine-R (2), which exhibited an IC50 value of 3.2 ± 2.6 µM against Plasmodium falciparum K1, whereas an IC50 value of >64.0 µM was evident for its cytotoxicity against MRC-5 cells.


Assuntos
Alcaloides/farmacologia , Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Ziziphus/química , Alcaloides/química , Alcaloides/isolamento & purificação , Antimaláricos/química , Antimaláricos/isolamento & purificação , Cromatografia Líquida , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Paquistão , Peptídeos Cíclicos/química , Raízes de Plantas/química , Teofilina/análogos & derivados , Teofilina/química
8.
Planta Med ; 82(18): 1568-1575, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27737476

RESUMO

Within an ongoing research program on saponins with potential antileishmanial activity, four previously undescribed saponins were isolated from Maesa argentea leaves and identified by LC-MS/MS, GC-MS, and 1D and 2D NMR spectroscopy as 3ß-O-{([ß-D-glucopyranosyl-(1 → 2)-α-L-rhamnopyranosyl-(1 → 2)-ß-D-galactopyranosyl-(1 → 3)]-[ß-D-galactopyranosyl-(1 → 2)]-ß-D-glucuronopyranosyl)}-21ß-angeloyloxy-22α-butanoyloxy-13ß,28-oxidoolean-16α,28α-diol (1), 3ß-O-{([ß-D-glucopyranosyl-(1 → 2)-α-L-rhamnopyranosyl-(1 → 2)-ß-D-galactopyranosyl-(1 → 3)]-[ß-D-galactopyranosyl-(1 → 2)]-ß-D-glucuronopyranosyl)}-21ß,22α-angeloyloxy-13ß,28-oxidoolean-16α,28α-diol (2), 3ß-O-{([ß-D-glucopyranosyl-(1 → 2)-α-L-rhamnopyranosyl-(1 → 2)-ß-D-galactopyranosyl-(1 → 3)]-[ß-D-galactopyranosyl-(1 → 2)]-ß-D-glucuronopyranosyl)}-21ß-angeloyloxy-22α-(E)-cinnamoyloxy-13ß,28-oxidoolean-16α,28α-diol (3), and 3ß-O-{([α-L-rhamnopyranosyl-(1 → 2)-ß-D-galactopyranosyl-(1 → 3)]-[ß-D-galactopyranosyl-(1 → 2)]-ß-D-glucuronopyranosyl)}-21ß-angeloyloxy-22α-(E)-cinnamoyloxy-13ß,28-oxidoolean-16α,28α-diol (4). Leaf material was obtained from a germinated seed that was clonally propagated using in vitro tissue culturing. Compounds 1-4 showed structural similarity with maesasaponins and maesabalides reported before from other Maesa spp. All four compounds showed in vitro activity against Plasmodium falciparum K1 and Leishmania infantum at micromolar concentrations. However, the observed inhibitory action must be considered nonspecific since they were also cytotoxic in the same concentration range.


Assuntos
Antiprotozoários/farmacologia , Primulaceae/química , Saponinas/farmacologia , Triterpenos/farmacologia , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/química , Folhas de Planta/química , Saponinas/química , Saponinas/isolamento & purificação , Triterpenos/química , Triterpenos/isolamento & purificação
9.
Planta Med ; 82(6): 559-72, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26845709

RESUMO

Filipendula ulmaria (meadowsweet) is traditionally used for the treatment of inflammatory diseases and as a diuretic and antirheumatic. Extracts of Filipendulae herba are on the market in the European Union as food supplements. Nevertheless, its active constituents remain to be revealed. During this study, the phytochemical composition of Filipendulae Ulmariae Herba was comprehensively characterised for the first time with two complementary generic ultrahigh-performance liquid chromatography-photodiode array-accurate mass mass spectrometry methods. Selective ion fragmentation experiments with a hybrid quadrupole-orbital trap mass spectrometer significantly contributed to compound identification: a total of 119 compounds were tentatively identified, 69 new to F. ulmaria. A rich diversity of phenolic constituents was detected and only a few non-phenolic phytochemicals were observed. Metabolisation and pharmacological studies should be conducted to investigate which of these constituents or metabolites there of contribute to the activity of F. ulmaria after oral intake.


Assuntos
Cromatografia Líquida/métodos , Filipendula/química , Espectrometria de Massas em Tandem/métodos , Flavonoides/análise , Flavonoides/química , Fenóis/análise , Fenóis/química , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Fitosteróis/análise , Fitosteróis/química , Plantas Medicinais/química , Proantocianidinas/análise , Proantocianidinas/química
10.
Planta Med ; 82(18): 1576-1583, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27776377

RESUMO

Stone diseases present a major health problem in the Western society, since both urinary and biliary stones occur with a relatively high prevalence of 10-12 % and 10-20 %, respectively, and demonstrate a high recurrence rate. At the moment treatment is mainly based on interventional procedures, or prophylactic and dissolution therapy. However, many of the current drugs cause severe side effects, and therefore, there is an increasing interest in natural medicines. At the moment no registered herbal medicinal products are available for treatment of gallstones. Since an infusion of Herniaria hirsuta L. has a proven efficacy against urolithiasis and cholelithiasis, its phytochemical composition has been investigated. Two previously undescribed triterpene saponins, 28-O-{[ß-D-xylopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 2)]-[ß-D-glucopyranosyl-(1-6)]-ß-D-glucopyranosyl}-medicagenic acid and 3-O-[α-L-rhamnopyranosyl-(1 → 3)-ß-D-glucuronopyranosyl]-28-O-{[ß-D-glucopyranosyl-(1 → 3)-ß-D-xylopyranosyl-(1 → 4)]-[ß-D-apiofuranosyl-(1 → 3)]-α-L-rhamnopyranosyl-(1 → 2)-ß-D-fucopyranosyl}-medicagenic acid and three known flavonoids, quercetin-3-O-(2″-O-α-L-rhamnopyranosyl)-ß-D-glucuronopyranoside, rutin, and narcissin (isorhamnetin-3-O-rutinoside), were isolated using flash chromatography and successive semi-preparative HPLC and were well characterized by MS and 1D and 2D NMR spectroscopic techniques. These findings could contribute to the development of a standardized extract that can be used in prophylaxis and treatment of gall and kidney stones.


Assuntos
Caryophyllaceae/química , Flavonoides/química , Saponinas/química , Cromatografia Líquida de Alta Pressão , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Ressonância Magnética Nuclear Biomolecular , Saponinas/isolamento & purificação , Saponinas/farmacologia
11.
Contact Dermatitis ; 75(5): 276-284, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27538353

RESUMO

BACKGROUND: Octylisothiazolinone (OIT) is used as an antifungal agent by the leather industry. OBJECTIVES: To show sensitization to OIT from leather, and to highlight the potential implications when cross-reactivity between OIT and methylisothiazolinone (MI) is studied. METHODS: Two patients with allergic contact dermatitis caused by a leather belt and shoes, respectively, were patch tested with methylchloroisothiazolinone (MCI)/MI, MI, MCI, OIT, and benzisothiazolinone (BIT). High-performance liquid chromatography with ultraviolet detection (HPLC-UV) was used to detect isothiazolinone derivatives in leather goods. Additionally, files of OIT-sensitized patients, observed at the KU Leuven department during the period 1990-2015, were retrospectively analysed. RESULTS: Both patients had been primarily sensitized to OIT, but the diagnosis in one of them could be achieved only when a higher patch test concentration of OIT (1000 ppm pet.) was used. HPLC-UV confirmed the presence of OIT in their leather goods. Non-relevant sensitization to MI was noted in both cases. Four additional cases of OIT sensitization from leather could be retrieved from the KU Leuven database. CONCLUSIONS: Non-occupational sensitization to OIT from leather may occur. Patch test concentrations of >250 ppm pet. may be necessary for diagnosis, and to show cross-reactivity with MI. Safer use limits for OIT in the leather industry may be needed.


Assuntos
Dermatite Alérgica de Contato/etiologia , Dermatoses do Pé/etiologia , Fungicidas Industriais/efeitos adversos , Sapatos/efeitos adversos , Tiazóis/efeitos adversos , Abdome , Adulto , Cromatografia Líquida de Alta Pressão , Vestuário/efeitos adversos , Reações Cruzadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Conservantes Farmacêuticos/efeitos adversos
12.
Phytother Res ; 30(10): 1624-1633, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27282639

RESUMO

Nymphoides indica (L.) Kuntze (Menyanthaceae) is traditionally used in the Indian subcontinent. However, scientific data reporting its constituents are poor. This study aimed at evaluating its phytochemical constituents and various biological activities. Phytochemical investigations of the extracts and fractions resulted in the isolation of 5 lipophilic compounds, i.e. azelaic (nonanedioic) acid (1) and 4-methyl-heptanedioic acid (3), hexadecanoic (2) and stearic acid (5) and the fatty alcohol hexadecanol (4); 3 seco-iridoids, i.e. 7-epiexaltoside (6), 6″,7″-dihydro-7-epiexaltoside (7) and menthiafolin (8); 3 flavonoids, i.e. 3,7-di-O-methylquercetin-4'-O-ß-glucoside (9), 3-O-methylquercetin-7-O-ß-glucoside (10) and 3,7-di-O-methylquercetin (11); scopoletin (12) and ferulic acid (13); and the monoterpenoids foliamenthoic acid (14) and 6,7-dihydrofoliamenthoic acid methyl ester (15). Compounds 1-5 showed moderate antimicrobial activities, whereas compound 9 presented mild antiprotozoal activities against Trypanosoma brucei (IC50 8 µM), Leishmania infantum (IC50 32 µM) and Trypanosoma cruzi (IC50 30 µM). Antiglycation activity was shown by compounds 7 (IC50 0.36 mM), 10 (IC50 0.42 mM) and 15 (IC50 0.61 mM). Finally α-glucosidase inhibition was shown by compounds 7, 9, 11 and 13-15. It could be concluded that N. indica leaf extracts possess mild to moderate antimicrobial, antiprotozoal, antioxidant and antidiabetic activities. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Araceae/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Folhas de Planta/química
13.
Molecules ; 21(10)2016 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-27681714

RESUMO

The exudate of Ferula narthex Boiss. (Apiaceae) is widely used in the Indian subcontinent as a spice and because of its health effects. Six sesquiterpene coumarins have been isolated from this exudate: feselol, ligupersin A, asacoumarin A, 8'-O-acetyl-asacoumarin A, 10'R-karatavacinol and 10'R-acetyl-karatavacinol. Based on its use in infectious and diabetic conditions, the isolated constituents were evaluated for antimicrobial and antiglycation activities. Some compounds showed activity against protozoal parasites, asacoumarin A being the most active one against Plasmodium falciparum K1 (IC50 1.3 µM). With regard to antiglycation activity, in the BSA-glucose test, ligupersin A displayed the highest activity (IC50 0.41 mM), being more active than the positive control aminiguanidine (IC50 1.75 mM). In the BSA-MGO assay, the highest activity was shown by 8'-O-acetyl-asacoumarin A (IC50 1.03 mM), being less active than aminoguanidine (IC50 0.15 mM). Hence, the antiglycation activity of the isolated constituents was due to both oxidative and non-oxidative modes of inhibition.

14.
Contact Dermatitis ; 73(3): 142-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26256947

RESUMO

BACKGROUND: Methylisothiazolinone (MI) contact allergy is severely affecting consumers with allergic contact dermatitis, owing to its presence in cosmetics, household detergents, and water-based paints, in particular. Data on the true isothiazolinone concentrations in these products are scarce, and labelling may be incorrect. OBJECTIVES: To report on the MI concentrations in such products marketed in Belgium, in order to verify the accuracy of labelling (when applicable) and compliance with EU regulations. MATERIALS AND METHODS: Thirty cosmetics (18 leave-on and 12 rinse-off), eight detergents and four paints were analysed for MI by the use of high-performance liquid chromatography with ultraviolet detection. RESULTS: The analysed leave-on, and to a lesser extent the rinse-off, cosmetics, contained MI at concentrations far exceeding the permitted 100 ppm use concentration. Household detergents contained high concentrations of MI, and mislabelling occurred for both cosmetics and detergents. The (limited) data on paints are in line with the existing literature. CONCLUSION: Cosmetics and detergents may facilitate contact sensitization because of a (too) high MI concentration, and mislabelling may make its avoidance extremely difficult. Safer use concentrations and correct labelling should be ensured by adequate quality control.


Assuntos
Cosméticos/química , Detergentes/química , Pintura/análise , Conservantes Farmacêuticos/análise , Rotulagem de Produtos/normas , Tiazóis/análise , Bélgica , Dermatite Alérgica de Contato/etiologia , Humanos
15.
BMC Complement Altern Med ; 15: 52, 2015 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-25879228

RESUMO

BACKGROUND: Metabolic syndrome (MetS) comprises a spectrum of clinical phenotypes in which dyslipidemia, dysglycemia and hypertension are clustered and where all share a high level of oxidative stress and an increased risk of cardiovascular disease. This study examines the effect of a nutritional supplement combining red yeast rice and olive fruit extract on the lipid profile and on oxidative stress in a population of patients with MetS. METHODS: In a double blind placebo controlled randomized trial, 50 persons with MetS, as defined by the ATPIII criteria, received the study product or placebo for 8 weeks. The study product contained 10.82 mg of monacolins and 9,32 mg of hydroxytyrosol per capsule, and is commercialized as Cholesfytol plus. The primary outcome measure was the difference in LDL reduction between intervention and control groups. Furthermore, differences in changes of CH, HDL, ApoA1, ApoB, HbA1c and oxLDL were measured, as well as side-effects, CK elevation, changes in clinical parameters and in cardiovascular risk. RESULTS: In the intervention group, LDL cholesterol was lowered by 24% whereas it increased by 1% in the control group (p < 0.001). Other effects observed were a change in total cholesterol (-17% in the intervention group vs +2% in the control group, p < 0.001), apolipoprotein B (-15% vs +6%, p < 0.001), and TG (-9% vs + 16%, p = 0.02). Oxidized LDL decreased by 20% vs an increase of 5% in the control group (p < 0.001). Systolic and diastolic arterial blood pressure decreased significantly by 10 mmHg (vs 0% in the control group, p = 0.001) and 7 mmHg (vs 0% in the control group, p = 0.05) respectively. One person in the intervention group, who suffered from Segawa's syndrome, dropped out because of severe muscle ache. CONCLUSIONS: The combination of active products in this study may be an alternative approach to statins in people who do not need, or cannot or do not want to be treated with chemical statins. Side effects, effects on oxidative stress and on glucose metabolism need to be examined more thoroughly. TRIAL REGISTRATION: Clinicaltrials.gov NCT02065180 (February 2014).


Assuntos
Produtos Biológicos/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipídeos/sangue , Síndrome Metabólica/tratamento farmacológico , Olea/química , Extratos Vegetais/uso terapêutico , Adulto , Produtos Biológicos/farmacologia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Colesterol/sangue , LDL-Colesterol/sangue , Suplementos Nutricionais , Método Duplo-Cego , Dislipidemias/tratamento farmacológico , Feminino , Frutas , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Lipoproteínas LDL/sangue , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Fitoterapia , Extratos Vegetais/farmacologia , Fatores de Risco
16.
Planta Med ; 80(12): 1001-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25098935

RESUMO

Both advanced glycation endproducts and advanced lipoxidation endproducts are implicated in many age-related chronic diseases and in protein ageing. In this study, kawain, methysticin, and dihydromethysticin, all belonging to the group of kavalactones, were identified as advanced glycation endproduct inhibitors. With IC50 values of 43.5 ± 1.2 µM and 45.0 ± 1.3 µM for kawain and methysticin, respectively, the compounds inhibited the in vitro protein glycation significantly better than aminoguanidine (IC50 = 231.0 ± 11.5 µM; p = 0.01), an established reference compound. Kawain and methysticin also inhibited the formation of dicarbonyl compounds, which are intermediates in the process of advanced glycation endproduct formation. Similarly, kawain and aminoguanidine prevented the formation of thiobarbituric reactive substances in both low-density lipoprotein and linoleic acid oxidation. Moreover, kawain and aminoguanidine prevented advanced glycation endproduct formation by chelating Fe(3+) and Cu(2+) two to three times better than aminoguanidine. Furthermore, kawain increased the mean life span of Caenorhabditis elegans exposed to high glucose. With glycation inhibiting, lipid peroxidation inhibiting, metal chelating properties, and life span extending ability, kavalactones show a high potential as advanced glycation endproducts and advanced lipoxidation endproduct inhibitors.


Assuntos
Produtos Finais de Glicação Avançada/antagonistas & inibidores , Guanidinas/farmacologia , Lactonas/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Piranos/farmacologia , Pironas/farmacologia , Animais , Caenorhabditis elegans , Quelantes/farmacologia , Glucose/administração & dosagem , Glucose/metabolismo , Glicosilação/efeitos dos fármacos , Ácido Linoleico/metabolismo , Lipoproteínas LDL/metabolismo , Longevidade/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
17.
BMC Complement Altern Med ; 13: 178, 2013 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-23866314

RESUMO

BACKGROUND: In recent years, red yeast rice (RYR) supplements have been marketed aggressively as a natural way to lower cholesterol; however, the large majority of commercially available products have not been studied according to current research standards. METHODS: In a double blind placebo controlled randomized trial, 52 physicians and their spouses with a total cholesterol level of > 200 mg/dL were randomly allocated to receive a RYR extract or placebo for 8 weeks. As a primary outcome measure, we compared the before-after difference in lipid levels between both groups. As secondary outcome measures we looked at side-effects, CK elevation and a change in cardiovascular risk. RESULTS: LDL (low density lipoprotein) cholesterol was lowered with 36 mg/dL (22%) and total cholesterol with 37 mg/dL (15%) in the intervention group. This result was statistically significant as compared to the control group, in which no reduction in total cholesterol and LDL was observed (p < 0.001). There was no marked difference in CK (creatine kinase)-elevation or reported side-effects between study groups. In 5/31 participants in the intervention group, the lipid lowering effect resulted in lower cardiovascular risk as measured with SCORE (Systematic COronary Risk Evaluation). CONCLUSIONS: The RYR formulation under study was effective in lowering cholesterol and LDL cholesterol in this study population. RYR therapy may be an attractive and relatively well studied alternative in patients who are intolerant for statins or who have objections against pharmacological lipid lowering. However, consumers need to be warned that the actual content of commercially available preparations is not assured by governmental regulations, which raises effectiveness and safety issues. TRIAL REGISTRATION: Clinicaltrials.gov, nr: NCT01558050.


Assuntos
Anticolesterolemiantes/farmacologia , Produtos Biológicos/farmacologia , Colesterol/sangue , Suplementos Nutricionais , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Hipercolesterolemia/sangue , Adulto , Idoso , Anticolesterolemiantes/uso terapêutico , Ascomicetos , Produtos Biológicos/uso terapêutico , Doenças Cardiovasculares/etiologia , LDL-Colesterol/sangue , Método Duplo-Cego , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/prevenção & controle , Masculino , Pessoa de Meia-Idade , Médicos , Fatores de Risco
20.
Planta Med ; 77(11): 1139-48, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21328178

RESUMO

The extracts of two medicinal plants used in traditionalmedicine against malariawere characterized by means of an LC­SPE­NMR and LC­MS platform. The structure of a series of major constituents from Bafodeya benna, as well as minor constituents from Ormocarpum kirkii, was determined. Bafodeya benna was found to contain (2R,3R)-taxifolin-3-O-α-L-rhamnoside or astilbin, and its isomers neoastilbin, neoisoastilbin, and isoastilbin, as well as quercetin-3-O-α-L-rhamnoside. From Ormocarpum kirkii, a series of known flavonoids and biflavonoids was obtained, as well as three new compounds, i.e., 7,7''-di-O-ß-D-glucosyl-(−)-chamaejasmin, 7-O-ß-D-glucosyl-(I-3,II-3)-biliquiritigenin, and isovitexin-(I-3,II-3)-naringenin. The isolated constituents may explain, at least in part, the traditional use against malaria. LC­SPE­NMR, in combination with LC­MS, is a powerful tool for the fast characterization of plant extracts, in order to define priorities at an early stage of a fractionation procedure. In addition, herbal medicinal products can completely be characterized, both with regard to their major as well as their minor constituents.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Extratos Vegetais/química , Plantas Medicinais/química , Antimaláricos/química , Biflavonoides/química , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão , Chrysobalanaceae/química , Fabaceae/química , Flavonoides/química , Flavonóis/química , Malária/tratamento farmacológico , Folhas de Planta/química
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