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1.
Molecules ; 24(14)2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31336918

RESUMEN

An aminoborane side product from the nicergoline manufacture process was identified by single-crystal X-ray diffraction. As boranes of pharmaceutical molecules are quite rare, the binding potential of the BH3 group was investigated and compared with similar compounds using Cambridge Structural Database (CSD). Surprisingly, the packing was stabilized by a dihydrogen bond, which triggered a false alert for too-short contact of hydrogen atoms in IUCR checkCIF. As the dihydrogen bond concept is not widely known, such an alert might mislead crystallographers to force -CH3 optimal geometry to -BH3 groups. The B-H distances equal to or less than 1.0 Å (17% of the CSD structures) are substantially biased when analyzing the structures of aminoborane complexes in CSD. To conduct proper searching, B-H bond length normalization should be applied in the CSD search.


Asunto(s)
Boranos/química , Enlace de Hidrógeno , Hidrógeno/química , Nicergolina/química , Cristalografía por Rayos X , Modelos Moleculares , Conformación Molecular , Estructura Molecular
2.
Toxins (Basel) ; 11(8)2019 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-31349616

RESUMEN

Ergot, fungal genus Claviceps, are worldwide distributed grass pathogens known for their production of toxic ergot alkaloids (EAs) and the great agricultural impact they have on both cereal crop and farm animal production. EAs are traditionally considered as the only factor responsible for ergot toxicity. Using broad sampling covering 13 ergot species infecting wild or agricultural grasses (including cereals) across Europe, USA, New Zealand, and South Africa we showed that the content of ergochrome pigments were comparable to the content of EAs in sclerotia. While secalonic acids A-C (SAs), the main ergot ergochromes (ECs), are well known toxins, our study is the first to address the question about their contribution to overall ergot toxicity. Based on our and published data, the importance of SAs in acute intoxication seems to be negligible, but the effect of chronic exposure needs to be evaluated. Nevertheless, they have biological activities at doses corresponding to quantities found in natural conditions. Our study highlights the need for a re-evaluation of ergot toxicity mechanisms and further studies of SAs' impact on livestock production and food safety.


Asunto(s)
Claviceps/química , Alcaloides de Claviceps/toxicidad , Micotoxinas/toxicidad , Xantenos/toxicidad , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Alcaloides de Claviceps/análisis , Células HeLa , Humanos , Células Jurkat , Mitocondrias/efectos de los fármacos , Micotoxinas/análisis , Micotoxinas/farmacología , Xantenos/análisis
3.
Nat Prod Commun ; 11(5): 681-3, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27319150

RESUMEN

Callus cultures of Juniperus virginiana L. (varieties 'Hetzii', 'Glauca', 'Grey Owl') were derived from fresh leaves of garden-grown trees on Schenk and Hildebrandt medium supplemented with 3.0 mg/L of α-naphthaleneacetic acid, 0.2 mg/L of kinetin and 15 mg/L of ascorbic acid. The growth characteristics of one-year-old and two-years-old cultures were determined. The maximum biomass in all varieties was achieved on the 35th day of the cultivation period. The increase in fresh weights of two-years-old callus cultures, when compared with one-year-old callus cultures, was as follows: variety 'Hetzii' by 25%, variety 'Glauca' by 29% and variety 'Grey Owl' by 49%. J. virginiana suspension cultures (varieties 'Hetzii', 'Glauca', 'Grey Owl') were derived from two-years-old callus cultures on Schenk and Hildebrandt medium supplemented with 3.0 mg/L of α-naphthaleneacetic acid, 0.2 mg/L of kinetin and 15 mg/L of ascorbic acid. The maximum biomass of all varieties was found on the 21st day of the cultivation period. These results indicate that a sub-cultivation interval of 35 days for callus cultures and of 21st days for suspension cultures can be recommended. The callus and suspension cultures of J. virginiana of the variety 'Glauca' have the best survivability and thus provide the most biomass.


Asunto(s)
Juniperus , Técnicas de Cultivo de Tejidos
4.
J Agric Food Chem ; 56(24): 11883-9, 2008 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-19112647

RESUMEN

The fruit of Lonicera caerulea L. (blue honeysuckle; Caprifoliaceae) and its phenolic fraction were analyzed for nutrients and micronutrients. The phenolic fraction was prepared from berries percolated with 0.1% H3PO4 and SPE using Sepabeads SP207. The sugar and lipid content was analyzed by HPLC and GC-MS. The total content of anthocyanins was determined using the pH differential absorbance method and aliphatic acids by capillary electrophoresis. MicroLC-MS/MS was used for determination of cyanidin-3-glucoside (the predominant anthocyanin), 3,5-diglucoside, and 3-rutinoside, paeonidin-3-glucoside, 3,5-diglucoside, and 3-rutinoside, delphinidin-3-glucoside and 3-rutinoside, pelargonidin-3-glucoside, 3,5-diglucoside, and 3-rutinoside, quercetin, its 3-glucoside, and 3-rutinoside, epicatechin, protocatechuic, gentisic, ellagic, ferulic, caffeic, chlorogenic, and coumaric acids. The phenolic fraction displayed Folin-Ciocalteu reagent reducing (335 +/- 15 microg of gallic acid equivalent/mg) and DPPH and superoxide scavenging activity (IC50 12.1 +/- 0.1 and 115.5 +/- 6.4 microg/mL) and inhibited rat liver microsome peroxidation (IC50 160 +/- 20 microg/mL). The freeze-dried fruit and its phenolic fraction reduced the biofilm formation and adhesion to the artificial surface of Candida parapsilosis, Staphylococcus epidermidis, Escherichia coli, Enterococcus faecalis, and Streptococcus mutans.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Lonicera/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Antocianinas/química , Bacterias/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Hongos/efectos de los fármacos , Hongos/fisiología , Peroxidación de Lípido/efectos de los fármacos , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Extractos Vegetales/química
5.
J Chromatogr A ; 1081(1): 87-91, 2005 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-16013603

RESUMEN

Butorphanol tartrate is a synthetic opioid agonist-antagonist used as analgesic, possessing three chiral centres in the basic part of the molecule. Its chiral purity is routinely controlled only by optical rotation. A new capillary zone electrophoresis method, capable to separate the enantiomers of butorphanol and intermediate of its synthesis, cycloamine, was developed. Different electrolyte composition (type and concentration of carrier ion, pH, and organic solvent addition), and type and concentration of several chiral selectors (natural and modified cyclodextrins) were tested. Using the optimized conditions (acidic electrolyte with the addition of highly sulphated gamma-cyclodextrin) as low as 0.05% of undesirable enantiomers can be detected. Selected method characteristics, i.e., linearity (0-50 mg/l), precision (2.5% at 20 mg/l), and accuracy (101 +/- 2% at 20 mg/l) were evaluated. The optimized method was applied for the analysis of real batches of butorphanol and cycloamine. It was found that butorphanol tartrate manufactured by IVAX Pharmaceuticals contains less than 0.05% of undesirable enantiomer.


Asunto(s)
Butorfanol/análogos & derivados , Butorfanol/aislamiento & purificación , Electroforesis Capilar/métodos , Butorfanol/normas , Reproducibilidad de los Resultados , Estereoisomerismo
6.
J Chromatogr A ; 1066(1-2): 255-8, 2005 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-15794580

RESUMEN

Lisuride is an ergot alkaloid derivative with dopaminergic activity. It is used for treatment of Parkinsonism and some other diseases associated with high level of prolactine. Lisuride is a chiral compound derived from natural ergot alkaloids. A new capillary zone electrophoresis (CZE) method capable of separating the enantiomers of lisuride was developed. Using the optimized conditions (acidic electrolyte with the addition of gamma-cyclodextrin (gamma-CD)) as low as 0.02% of undesirable L-lisuride can be detected. Selected method characteristics, i.e., linearity (0-20 mg/l), precision (2.0% at 5 mg/I), and accuracy (101 +/- 4% at 5 mg/l) were evaluated. The optimized method was applied for the analysis of real batches of Lisuride hydrogenmaleate and Lisuride base manufactured by IVAX Pharmaceuticals. It was found that they contain less than 0.02% of undesirable L-enantiomer.


Asunto(s)
Electroforesis Capilar/métodos , Lisurida/aislamiento & purificación , Indicadores y Reactivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estereoisomerismo , gamma-Ciclodextrinas
7.
Eur J Nutr ; 42(1): 61-6, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12594543

RESUMEN

BACKGROUND & AIMS: Yacon ( Smallanthus sonchifolius, Asteraceae) is a native Andean plant, cultivated for its tubers throughout South America. The leaves are used in folk medicine as a medicinal tea for hypoglycemia. This paper describes the antioxidant activity of various extracts from S. sonchifolius leaves for their content of phenolic components. METHODS: The dried leaves were extracted in several ways. Two fractions were selected for their high content of phenolic compounds and analyzed by RP-HPLC. The antioxidant activity of these fractions was tested in 1,1-diphenyl-2-picrylhydrazyl (DPPH) and xanthine/XOD superoxide radical scavenging assays, as inhibition of lipoperoxidation of subcellular membranes and as protective activity against oxidative injury of rat hepatocytes in primary cultures. RESULTS AND CONCLUSIONS: The presence of protocatechuic (2.5 and 0.12 mg/g), chlorogenic (9.9 and 1.7 mg/g), caffeic (14.7 and 0.09 mg/g) and ferulic (traces) acids were determined in the two fractions. Both fractions showed potent antioxidant activity in DPPH (IC(50) = 16.1 +/- 3.4 and 24.3 +/- 2.7 mg/ml) and xanthine/XOD superoxide radical scavenging (42.0 +/- 20.3 and 34.3 +/- 11.4 SOD equivalents (U/mg)) tests, they inhibited the lipoperoxidation of rat liver subcellular membranes and they protected rat hepatocytes against oxidative injury. Our results may predetermine the use of S. sonchifolius leaves in human diet as a potential remedy in the prevention of chronic diseases caused by radicals, e. g., arteriosclerosis.


Asunto(s)
Antioxidantes/farmacología , Asteraceae/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Animales , Antioxidantes/análisis , Células Cultivadas , Cromatografía Líquida de Alta Presión/métodos , Relación Dosis-Respuesta a Droga , Cinética , Peroxidación de Lípido/efectos de los fármacos , Hígado/citología , Hígado/metabolismo , Masculino , Fenoles/análisis , Extractos Vegetales/análisis , Hojas de la Planta/química , Ratas , Ratas Wistar
8.
Pharmacol Res ; 47(1): 17-26, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12526857

RESUMEN

To study the influence of polymerised polyphenolics (PP), a fraction of silymarin (SM), on lipids and oxidant status, rats were fed high-cholesterol (1%), high-fat (10%) diets containing either lard fat (LFD) rich in saturated/monounsaturated fatty acids, or currant oil (COD) rich in polyunsaturated fatty acids. PP and SM were administered as dietary supplements (0.1-0.5-1.0%) for 3 weeks. PP (1%) decreased cholesterol (C) in VLDL (from 0.72+/-0.08 mmol l(-1) in LFD control to 0.35+/-0.07 mmol l(-1), P<0.01, and from 0.33+/-0.05 mmol l(-1) in COD control to 0.09+/-0.02 mmol l(-1), P<0.001), and increased HDL-C/VLDL-C ratio, however, without effect on the total plasma C and LDL-C. Liver C content (LFD 19.32+/-1.50 micromol g(-1), COD 18.64+/-2.13 micromol g(-1), N.S.) decreased after PP (1%) to 12.24+/-0.76 micromol g(-1), P<0.01, and 8.78+/-0.95 micromol g(-1), P<0.001, respectively. Triacylglycerols (TAG) in plasma and VLDL decreased after PP in the LFD group only, which displayed higher TAG levels than the COD group. Likewise, LFD caused a higher liver TAG content than did COD (31.16+/-3.00 micromol g(-1) versus 17.31+/-1.48 micromol g(-1), P<0.01), and PP (1%) decreased liver TAG only in rats fed LFD (19.55+/-2.43 micromol g(-1), P<0.02). Blood glutathione (GSH) increased after PP (1%) in the LFD group from 0.97+/-0.11 to 1.54+/-0.19 mmol l(-1) (P<0.05) and in the COD group from 0.58+/-0.15 to 1.23+/-0.10 mmol l(-1) (P<0.01), while liver GSH and plasma TBARS did not change. On principle, effects of PP were dose-dependent and parallel to SM. These results suggest that the polyphenolic fraction of SM positively modifies lipoprotein profile, counteracts the development of fatty liver and ameliorates an antioxidant status in circulation.


Asunto(s)
Colesterol en la Dieta/metabolismo , Colesterol en la Dieta/farmacología , Flavonoides , Lipoproteínas/sangre , Fenoles/farmacología , Polímeros/farmacología , Silimarina/farmacología , Animales , Grasas de la Dieta/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratas , Ratas Wistar
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