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1.
J Agric Food Chem ; 68(14): 4176-4186, 2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-32181655

RESUMEN

Worldwide, parasitic gastrointestinal nematodes continue to threaten animal health, welfare, and production in outdoor breeding systems of small ruminants. For more than 50 years, the control of these parasitic worms has relied on the use of commercial synthetic anthelmintics. However, anthelmintic resistance in worm populations is nowadays widespread and requires novel solutions. The use of tannin-rich plants has been suggested as an alternative to synthetic anthelmintics to control gastrointestinal nematodes. The majority of previous studies have focused on the activity of proanthocyanidins (syn condensed tannins), and less is known about ellagitannins. In this study, the effects of 30 structurally unique ellagitannins on the exsheathment of third-stage infective larvae were examined on Haemonchus contortus and Trichostrongylus colubriformis by the in vitro larval exsheathment inhibition assay. Ellagitannins were found to be promising natural anthelmintics as they showed direct inhibition on larval exsheathment for both nematode species. In general, ellagitannins were more efficient at inhibiting the exsheathment of H. contortus larvae than those of T. colubriformis. The efficiency of inhibition increased as the degree of oligomerization or the molecular weight of the ellagitannin increased. Otherwise, we found no other structural features of ellagitannins that significantly affected the anthelmintic activity on the third-stage infective larvae. The effective concentrations were physiologically relevant and should be achievable in the gastrointestinal tract also in in vivo conditions.


Asunto(s)
Haemonchus/efectos de los fármacos , Taninos Hidrolizables/química , Larva/efectos de los fármacos , Extractos Vegetales/química , Tricostrongiloidiasis/tratamiento farmacológico , Trichostrongylus/efectos de los fármacos , Animales , Antihelmínticos/farmacología , Resistencia a Medicamentos , Haemonchus/parasitología , Taninos Hidrolizables/farmacología , Larva/parasitología , Estructura Molecular , Peso Molecular , Extractos Vegetales/farmacología , Polifenoles/química , Relación Estructura-Actividad , Trichostrongylus/parasitología
2.
Food Res Int ; 113: 115-130, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30195504

RESUMEN

In order to assist developing a natural, safe food-preservative, aqueous ethanolic extracts of leaves and berries of eight Finnish berry plants were fractionated with Sephadex LH-20 column chromatography. For each fraction, phenolic compounds were analyzed with NMR, UPLC-DAD-ESI-MS and HPLC-DAD. The antioxidant activities of the fractions were investigated using oxygen radical absorbance capacity (ORAC) assay, and the antibacterial activities were evaluated against foodborne pathogens Staphylococcus aureus and Escherichia coli. Antioxidant activities of the fractions correlated highly with both the total concentration and structural feature of phenolic compounds, including both flavonoids and non-flavonoid phenolics. ORAC value correlated strongly with the concentration of (+)-catechin, (-)-epicatecin, quercetin glycosides, and anthocyanins. Increase in size and number of sugar moieties may reduce the antioxidative activities of quercetin glycosides. Type of sugar moieties may have a significant role in influencing peroxyl-radicals scavenging ability of quercetin glycosides with monosaccharides as a single sugar moieties. Most of the fractions inhibited the target microbes. S. aureus strains expressed a higher sensitivity to phenolic compounds than E. coli strains.


Asunto(s)
Fraccionamiento Químico/métodos , Dextranos , Frutas/química , Fenoles/aislamiento & purificación , Extractos Vegetales/química , Hojas de la Planta/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Cromatografía/métodos , Cromatografía Líquida de Alta Presión , Escherichia coli/efectos de los fármacos , Finlandia , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Fenoles/farmacología , Rosaceae/química , Rosales/química , Espectrometría de Masa por Ionización de Electrospray , Staphylococcus aureus/efectos de los fármacos , Vaccinium vitis-Idaea/química
3.
Food Chem ; 220: 266-281, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-27855899

RESUMEN

Phenolic compounds of berries and leaves of thirteen various plant species were extracted with aqueous ethanol and analyzed with UPLC-DAD-ESI-MS, HPLC-DAD, and NMR. The total content of phenolics was consistently higher in leaves than in berries (25-7856 vs. 28-711mg/100g fresh weight). Sea buckthorn leaves were richest in phenolic compounds (7856mg/100g f.w.) with ellagitannins as the dominant compound class. Sea buckthorn berries contained mostly isorhamnetin glycosides, whereas quercetin glycosides were typically abundant in most samples investigated. Anthocyanins formed the dominating group of phenolics in most dark-colored berries but phenolic acid derivatives were equally abundant in saskatoon and chokeberry berries. Caffeoylquinic acids constituted 80% of the total phenolic content (1664mg/100g f.w.) in bilberry leaves. B-type procyanidins and caffeoylquinic acids were the major phenolic compounds in hawthorn and rowanberry, respectively. Use of leaves of some species with prunasin, tyramine and ß-p-arbutin, may be limited in food applications.


Asunto(s)
Frutas/química , Fenoles/análisis , Extractos Vegetales/análisis , Hojas de la Planta/química , Antocianinas/análisis , Cromatografía Líquida de Alta Presión , Crataegus/química , Glicósidos/análisis , Hippophae/química , Hidroxibenzoatos/análisis , Espectroscopía de Resonancia Magnética , Prunus/química , Quercetina/análogos & derivados , Quercetina/análisis , Ribes/química , Sorbus/química , Vaccinium macrocarpon/química , Vaccinium myrtillus/química , Vaccinium vitis-Idaea/química
4.
Talanta ; 161: 245-252, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27769403

RESUMEN

A direct quantitative proton nuclear magnetic resonance spectroscopy method was developed for the measurement of saccharides, organic acids and amino acids in potato (Solanum tuberosum L.) tuber filaments, a complex gel-like food matrix. The method requires minimal sample preparation. It is thus a faster alternative compared to liquid sample matrices, as well as an extension to methods analyzing only selected metabolites in the sample. The samples in this study were either raw or steamed potato strips that were either measured as D2O extracts or directly without extraction or derivatization steps (in situ technique). A total of 22 compounds were identified in extracts and 18 in potato strips. Of these, 20 compounds were quantifiable in potato extracts and 13 compounds in potato strips. The effect of thermal processing was reflected in the profile of analyzed compounds. One example was fumaric acid, which was completely lost in steamed samples in both measurement techniques. Additionally, the content of γ-aminobutyric acid in steamed potato strips was lower. In potato extracts, the contents of additional 7 compounds were statistically different. The raw and steamed samples separated into two groups with multivariate models both in extracts and potato strips, and these groups were linked to changes in aforementioned compounds. These results demonstrated that the in situ quantitative 1H NMR technique is a useful tool to analyze potato metabolites. This technique could be further applied to any gel-like complex matrix, meaning that lengthy sample pretreatment could be skipped.


Asunto(s)
Culinaria , Extractos Vegetales/química , Tubérculos de la Planta/química , Solanum tuberosum/química , Ácidos Acíclicos/análisis , Aminoácidos/análisis , Fructosa/análisis , Glucosa/análisis , Espectroscopía de Protones por Resonancia Magnética , Sacarosa/análisis
5.
Ren Fail ; 37(7): 1198-207, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26382171

RESUMEN

The hepatoprotective and nephroprotective activity of a polyphenol-rich fraction (BHPF) obtained from Bauhinia hookeri was investigated against CCl4-induced acute hepatorenal toxicity in mice. BHPF was administered (100, 200 and 400 mg/kg/day) for 5 days, then CCl4 was administered. BHPF pretreatment significantly (p < 0.001) inhibited the CCl4-induced increase in ALT, AST, ALP, LDH, total bilirubin, cholesterol, creatinine, uric acid, urea and malondialdehyde in a dose-dependent manner. In contrast, BHPF pretreatment markedly increased the contents of glutathione and superoxide dismutase in the liver and kidney tissues, indicating the strong in vivo antioxidant activity of BHPF. Pretreatment with BHPF preserved the hepatic architecture and conferred marked protection against necrosis and ballooning degeneration. Pretreatment with BHPF reduced the inflammatory cell aggregation and degenerative changes in the lining epithelium of the kidney tubules. It can be concluded that BHPF has a remarkable hepato- and nephroprotective activity by enhancing the antioxidant defense status, reducing lipid peroxidation and protecting against the histopathological changes induced by CCl4 in the liver and kidney tissues.


Asunto(s)
Tetracloruro de Carbono/toxicidad , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Riñón/patología , Extractos Vegetales/farmacología , Polifenoles/administración & dosificación , Sustancias Protectoras/administración & dosificación , Animales , Bauhinia , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Cromatografía Líquida de Alta Presión , Glutatión/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Ratones , Estrés Oxidativo/efectos de los fármacos , Superóxido Dismutasa/metabolismo
6.
J Agric Food Chem ; 62(49): 12015-26, 2014 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-25408277

RESUMEN

Leaves of bilberry (Vaccinium myrtillus L.) and lingonberry (Vaccinium vitis-idaea L.) are potential raw materials for food and health care products. Targeted (HPLC-DAD, HPLC-MS, and GC-FID) and nontargeted ((1)H NMR) approaches were applied to study the metabolomic profiles of these leaves. Chlorogenic acid was the major phenolic compound in bilberry leaves and arbutin in lingonberry leaves. Flavonol glycosides were another major group of phenolics in bilberry [5-28 mg/g DM (dry mass)] and lingonberry (15-20 mg/g DM) leaves. Contents of fatty acids were analyzed using GC-FID. The changes in the metabolomics profile during the season were apparent in bilberry but not lingonberry leaves. Negative correlation was found between the contents of lipids and phenolics. The consistency between the key results obtained by targeted and nontargeted analyses suggests nontargeted metabolomic analysis is an efficient tool for fast screening of various leaf materials.


Asunto(s)
Fenoles/química , Extractos Vegetales/química , Hojas de la Planta/química , Vaccinium myrtillus/química , Vaccinium vitis-Idaea/química , Cromatografía Líquida de Alta Presión , Espectrometría de Masas , Metabolómica , Fenoles/metabolismo , Extractos Vegetales/metabolismo , Hojas de la Planta/metabolismo , Vaccinium myrtillus/metabolismo , Vaccinium vitis-Idaea/metabolismo
7.
Phytochemistry ; 76: 178-83, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22273040

RESUMEN

A procyanidin dimer xyloside, catechin-(4α→8)-7-O-ß-xylopyranosyl-catechin, was isolated from the inner bark of Betula pendula and its structure was determined using 1D and 2D NMR, CD and high-resolution ESIMS. Interestingly, the 7-O-ß-xylopyranose unit was found to be present in the lower terminal unit of the dimer. In addition to this procyanidin dimer xyloside, an entire series of oligomeric and polymeric procyanidin xylosides was detected. Their structures were investigated by hydrophilic interaction HPLC-HRESIMS. Procyanidin glycosides are still rarely found in nature.


Asunto(s)
Betula/química , Biflavonoides/aislamiento & purificación , Catequina/análogos & derivados , Glicósidos/aislamiento & purificación , Corteza de la Planta/química , Proantocianidinas/aislamiento & purificación , Biflavonoides/química , Catequina/química , Catequina/aislamiento & purificación , Fraccionamiento Químico/métodos , Cromatografía Líquida de Alta Presión/métodos , Dicroismo Circular , Glicósidos/química , Interacciones Hidrofóbicas e Hidrofílicas , Conformación Molecular , Extractos Vegetales , Proantocianidinas/química
8.
J Sep Sci ; 34(22): 3158-65, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21998029

RESUMEN

A complex mixture of procyanidin aglycones was isolated by Sephadex LH-20 column chromatography from the silver birch inner bark, which is a polyphenol-rich source of natural antioxidants. Procyanidins were studied by using hydrophilic interaction liquid chromatography combined with high-resolution ESI-TOF-MS. A good chromatographic separation was achieved and procyanidins eluted according to their increasing degree of polymerization. Individual procyanidins were detected from dimers up to the degree of polymerization of 22 by their negative-ion mass spectra. The results showed that hydrophilic interaction liquid chromatography can be successfully applied for the analysis of high-molecular-weight procyanidins with enhanced sensitivity in electrospray mass spectrometry.


Asunto(s)
Betula/química , Cromatografía Líquida de Alta Presión/métodos , Corteza de la Planta/química , Extractos Vegetales/análisis , Proantocianidinas/análisis , Espectrometría de Masa por Ionización de Electrospray/métodos , Sensibilidad y Especificidad
9.
Nat Prod Commun ; 5(10): 1639-42, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21121264

RESUMEN

Two new phenolic compounds, 2,4,6-trihydroxy-5-methyl-acetophenone 2-O-beta-D-glucopyranoside (3), and benzyl alcohol 7-O-(3',4',6'-tri-O-galloyl)-beta-D-glucopyranoside (8), together with eight known phenolic compounds, were isolated from the 70% aqueous acetone extract of Eucalyptus gomphocephala DC. (Myrtaceae). The isolated compounds were elucidated based on their 1H, 13C, DQF-COSY, selective 1D-TOCSY, HSQC, and HMBC NMR spectroscopic and ESI-MS data. The antioxidant effect of the phenolic compounds was tested using 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl radical and super oxide anion radical scavenging assays. The cytotoxicity of the isolated compounds was evaluated using HeLa cell line.


Asunto(s)
Acetofenonas/aislamiento & purificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Eucalyptus/química , Depuradores de Radicales Libres/aislamiento & purificación , Ácido Gálico/análogos & derivados , Glucósidos/aislamiento & purificación , Fenoles/aislamiento & purificación , Acetofenonas/química , Antineoplásicos Fitogénicos/química , Ensayos de Selección de Medicamentos Antitumorales , Depuradores de Radicales Libres/química , Ácido Gálico/química , Ácido Gálico/aislamiento & purificación , Glucósidos/química , Células HeLa , Humanos , Fenoles/química , Extractos Vegetales/química
10.
Nat Prod Commun ; 5(4): 545-50, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20433069

RESUMEN

A liquid chromatography-diode array detection-electrospray ionization mass spectrometric (HPLC-PDA-ESI/MS/MS) method was used for the analysis of the phenolic composition of the ethanolic extract obtained from the leaves of Pleiogynium timorense (DC.) Leenh. Twenty compounds were detected and tentatively characterized. In addition, further phytochemical investigations of the extract resulted in the isolation of twelve major phenolic compounds. Evidence of the structures of these compounds was obtained based on the interpretation of the UV, 1H NMR, 13C NMR and DQF-COSY spectral data. The antioxidant effect of the ethanolic extract was examined in vitro using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and super oxide anion radical scavenging assays. DPPH radical scavenging activity was observed for the extract, with an IC50 of 21.9 microg/mL, while its super oxide anion scavenging activity was less pronounced, with an IC50 of 123.5 microg/mL The ethanolic extract showed significant hypoglycemic, antioxidant and anti-inflammatory properties. This study suggests that the ethanolic extract of Pleiogynium timorense is a potential source of antioxidant compounds, relatively non-toxic, and have possible beneficial health effects.


Asunto(s)
Anacardiaceae/química , Fenoles/química , Fenoles/farmacología , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Bioensayo , Compuestos de Bifenilo/química , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Hipoglucemiantes/farmacología , Masculino , Ratones , Resonancia Magnética Nuclear Biomolecular , Fenoles/aislamiento & purificación , Picratos/química , Hojas de la Planta/química , Ratas , Ratas Sprague-Dawley , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta , Superóxidos/química
11.
Magn Reson Chem ; 46(2): 195-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18098157

RESUMEN

Two phenylbutanoids, 7-{3R-[(4-hydroxyphenyl)butyl] beta-glucopyranosid-O-6-yl} 4-O-beta-glucopyranosylvanillin and 3-beta-glucopyranosyloxy-1-(4-hydroxyphenyl)-butanone were isolated from an aqueous methanol extract of the inner bark of Betula pendula. Their structures were determined by NMR spectroscopy and mass spectrometry. The complete assignment of proton and carbon signals was achieved by 1D and 2D NMR experiments: selective 1D TOCSY, HSQC, HMBC and DQF-COSY.


Asunto(s)
Benzoatos/aislamiento & purificación , Betula/química , Glucósidos/aislamiento & purificación , Fenoles/aislamiento & purificación , Benzoatos/química , Glucósidos/química , Conformación Molecular , Fenoles/química , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación
12.
Magn Reson Chem ; 44(6): 633-6, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16489551

RESUMEN

Three lignans were isolated from a bioactive fraction of the 70% aqueous acetone extract of the pine (Pinus sylvestris L.) bark. Their structures were identified by high-resolution positive ion EI mass spectrometry and NMR spectroscopy. The complete assignment of proton and carbon signals was achieved by 2D NMR experiments: HSQC, HMBC, DQF-COSY and NOESY.


Asunto(s)
4-Butirolactona/análogos & derivados , Benzofuranos/química , Guayacol/análogos & derivados , Lignanos/química , Pinus sylvestris/química , Glicoles de Propileno/química , 4-Butirolactona/química , Acetona/química , Guayacol/química , Lignanos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/química , Espectrometría de Masa por Ionización de Electrospray , Agua/química
13.
Life Sci ; 78(23): 2724-33, 2006 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-16313926

RESUMEN

The 70% alcohol extract of the Egyptian Morus alba L. root bark was fractionated over cellulose CC eluted with water, 50% methanol and finally with 100% methanol to yield 3 fractions (MRBF-1, MRBF-2 and MRBF-3), respectively. In continuation of chromatographic purification of 70% alcohol extract fractions of the Egyptian M. alba L. root bark, 4 compounds namely: mulberroside A, 5,7,2'-trihydroxyflavanone-4'-O-beta-D-glucoside and albanols A and B were isolated from MRBF-2 for the first time from the Egyptian plant. Experimentally induced atherosclerosis was produced by feeding rats a diet enriched in coconut oil (25% by weight) and cholesterol (2% by weight) for 21 days. Then, hypercholesterolemic rats were orally administered (MRBF-1, MRBF-2 and MRBF-3 fractions) in a dose of 500 mg kg(-1) day(-1) for 15 successive days, in order to evaluate their expected hypocholesterolemic activity. Lipid profile parameters such as plasma total cholesterol, LDL-C, VLDL-C, LDL:HDL ratio and triglycerides, as well as plasma and liver lipid peroxides and glutathione-S-transferase enzyme levels, serum paraoxonase enzyme level, LDL oxidation, LDL aggregation and LDL retention, were measured. Plasma and liver glutathione-S-transferase enzyme levels were unaffected in all studied groups. The results revealed that the administration of (MRBF-2 and/or MRBF-3) fractions resulted in alleviation of atherosclerotic state. Administration of MRBF-3 significantly retained plasma and liver peroxides towards their normal levels, and also, produced significant increase in resistance towards major atherogenic modifications; namely LDL oxidation, LDL aggregation and LDL retention by 44%, 30%, and 33%, respectively. Thus, it can be concluded that the consumption of MRBF-2 and (MRBF-3, in some extent) fractions of M. alba L. root bark 70% alcohol extract may act as a potent hypocholesterolemic nutrient and powerful antioxidant via the inhibition of LDL atherogenic modifications and lipid peroxides formation in hypercholesterolemic rats.


Asunto(s)
Anticolesterolemiantes/uso terapéutico , Antioxidantes/uso terapéutico , Aterosclerosis/tratamiento farmacológico , Hipercolesterolemia/tratamiento farmacológico , Morus/química , Fitoterapia , Extractos Vegetales/uso terapéutico , Animales , Anticolesterolemiantes/farmacología , Antioxidantes/farmacología , Aterosclerosis/sangre , Aterosclerosis/complicaciones , Fraccionamiento Químico , Colesterol/sangre , Colesterol en la Dieta/administración & dosificación , Modelos Animales de Enfermedad , Hipercolesterolemia/sangre , Hipercolesterolemia/complicaciones , Masculino , Extractos Vegetales/farmacología , Raíces de Plantas/química , Ratas , Ratas Wistar
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