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1.
Rev. chil. cardiol ; 42(2): 82-89, ago. 2023. tab
Artículo en Español | LILACS | ID: biblio-1515099

RESUMEN

Objetivo: Obtener un fitofármaco a base de extracto seco de limón con estándares de calidad, procesamiento amigable con el medio ambiente y con antecedentes de efectividad y seguridad, evaluando sus efectos en pacientes hipertensos con frecuentes crisis hipertensivas. Métodos y resultados: Se seleccionó la población de limónes de las Regiones Metropolitana y Coquimbo con las concentraciones más altas de ácido ascórbico y flavonoides totales, respectivamente. Se utilizó liofilización para obtener jugo de limón en polvo. Sólo durante el período de estudio, se informó un caso de aumento/ crisis hipertensiva. La formulación con la concentración más alta de ácido ascórbico disminuyó la presión arterial sistólica y diastólica en 16 mmHg desde 10 minutos hasta 60 minutos. Por otro lado, la formulación con mayor concentración de flavonoides disminuyó la presión arterial en 12 a 30 mmHg desde 5 a 60 minutos. Conclusión: Se obtuvo un producto innovador como complemento al manejo de los aumentos de presión arterial. Los principios activos con mayor contribución al mecanismo antihipertensivo del jugo de limón corresponden a compuestos fenólicos, específicamente, flavonoides.


Aim: To obtain a product based on a dry extract of standardized phytodrug lemon with high quality standards, using an environmentally friendly process; to evaluate its effects in hypertensive patients suffering frequent episodes of hypertensive crisis. Methods and Results: Lemons with high concentration of ascorbic acid (Coquimbo Region) or total flavonoids (Metropolitan Region) were selected. Lyophilization was used to obtain juice powder. During the study period only one case of hypertensive crisis was reported. The formula with the highest concentration of ascorbic acid decreased systolic and diastolic blood pressure by 16 mmHg from 10 minutes up to 60 minutes. On the other hand, the formula with the highest concentration of flavonoids decreased blood pressure from 12 to 30 mmHg between 5 and 60 minutes. Conclusion: An novel product to help decrease acutely elevated blood pressure was obtained that can be used as a complement to the management of acute blood pressure rises. The active principles with greater contribution to the antihypertensive mechanism of lemon juice corresponded to phenolic compounds, specifically flavonoids.


Asunto(s)
Humanos , Extractos Vegetales/uso terapéutico , Citrus/química , Jugos de Frutas y Vegetales , Hipertensión Maligna/tratamiento farmacológico , Ácido Ascórbico/análisis , Espectrofotometría , Factores de Tiempo , Flavonoides/análisis , Extractos Vegetales/farmacología , Cromatografía Líquida de Alta Presión , Medicamento Fitoterápico , Presión Arterial/efectos de los fármacos
2.
Biol Res ; 53(1): 55, 2020 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-33228801

RESUMEN

BACKGROUND: Gunnera tinctoria has been collected by Mapuche-Pewenche people for food and medicinal purposes. The high polyphenol content of methanolic extract from G. tinctoria leaves with chemical constituents such as ellagic acid and quercetin derivatives suggests its application to prevent endothelial dysfunction and oxidative stress. The aim of this study was to provide evidence of the protective effect of this extract on endothelial function by reducing oxidative stress induced by high D-glucose and H2O2, as well as by stimulating nitric oxide (NO) levels in human umbilical vein endothelial cells (HUVECs). RESULTS: A methanolic extract with a high content of polyphenols (520 ± 30 mg gallic acid equivalents/g dry extract) was obtained from G. tinctoria leaves. Its main constituent was ellagic acid. The results of Ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays of the extract confirmed its antioxidant activity by inhibition pathway of radical species. The incubation of HUVECs with the extract decreased the apoptosis and reactive oxygen species (ROS) synthesis induced by high extracellular concentration of D-glucose or hydrogen peroxide. The extract increased endothelial NO levels and reduced vasoconstriction in human placental vessels. CONCLUSIONS: This study provides evidence about the antioxidant and endothelial protective properties of methanolic G. tinctoria leaf extract. The extract improves the availability of NO in HUVECs, inhibiting the production of ROS and vasoconstriction.


Asunto(s)
Antioxidantes/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Peróxido de Hidrógeno , Estrés Oxidativo , Extractos Vegetales/farmacología , Apoptosis , Femenino , Humanos , Polifenoles/farmacología , Embarazo , Especies Reactivas de Oxígeno
3.
Front Pharmacol ; 11: 780, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32536867

RESUMEN

Weinmannia trichosperma Cav. (Cunoniaceae) (local name, tineo; Mapuche names, madén, mëdehue) is an endemic species of Chile and Argentina used in Mapuche traditional medicine in the treatment of chronic diarrhea, inflammation, and wound healing. This study focused on the isolation, analysis, and characterization of the biological activity of compounds and bark extracts from this plant for the first time. The infusion and tincture of the bark were characterized regarding antioxidant and important enzyme inhibitory activities, phenolics, and flavonoids content and UHPLC-ESI-OT-MS metabolite profiling. Twenty-five metabolites were detected in the medicinal infusion of W. trichosperma, three flavonols were isolated: isoastilbin, neoisoastilbin, and neoastilbin ((2R,3S)-, (2S,3R)-, and (2S,3S)-dihydroquercetin 3-O-alpha-l-rhamnoside) by countercurrent chromatography, and the isomers were quantified in the bark using a validated analytical HPLC methodology. The antioxidant properties were measured by ABTS, DPPH, FRAP, ORAC, and TEAC methods. The infusion displayed a strong DPPH and ABTS scavenging activity (IC50 = 20.58 and 3.070 µg ml-1, respectively) while a moderated effect was observed in the FRAP, ORAC, and ABTS assays. The infusion showed a content of phenolic and flavonoid compounds of 442.1 mg GAE g-1 and 15.54 mg QE g-1, respectively. Furthermore, the infusion showed a good and promissory inhibitory activity (33.80%, 33.12%, and 82.86% for AChE, BuChE, and 5-hLOX, respectively) and isoastilbin (51.70%, 50.10%, and 34.29-80.71% for AChE, BuChE, and 5-hLOX, respectively). The biomolecules identified in this study support the traditional uses of this bark and the potential industrial interest from this Valdivian plant species.

4.
Food Chem ; 314: 126166, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31972406

RESUMEN

The occurrence of the quercetin oxidation metabolite 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (BZF), whose antioxidant potency is notably higher than the antioxidant potency of quercetin, was investigated in twenty quercetin-rich plant foods. BZF was identified (HPLC-DAD-ESI-MS/MS) only in the dry outer scales of onions and shallots. Aqueous extracts of onions (OAE) and shallots (SAE) were evaluated for their antioxidant and cytoprotective properties. OAE, whose potency did not differ from SAE, protected ROS-exposed Caco2 cells against oxidative (78%) and cellular (90%) damage at a 3 µg/L concentration (corresponding to 0.03 nM of BZF). After chromatographic resolution of OAE, the BZF peak accounted fully and exclusively for its antioxidant effect. The antioxidant effects of OAE and of a pure BZF were described by two perfectly overlapping curves whose concentration-dependence was within the 3 × 10-4 to 102 nM BZF range. Such unprecedented low concentrations place BZF-containing plants on the frontier of the search for novel sources of antioxidants.


Asunto(s)
Antioxidantes/farmacología , Benzofuranos/análisis , Benzofuranos/farmacología , Cebollas/química , Quercetina/metabolismo , Antioxidantes/química , Benzofuranos/metabolismo , Células CACO-2 , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Frutas/química , Humanos , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Sustancias Protectoras/química , Sustancias Protectoras/farmacología , Espectrometría de Masas en Tándem , Verduras/química
5.
Biol. Res ; 53: 55-55, 2020. ilus, graf, tab
Artículo en Inglés | LILACS | ID: biblio-1505781

RESUMEN

BACKGROUND: Gunnera tinctoria has been collected by Mapuche-Pewenche people for food and medicinal purposes. The high polyphenol content of methanolic extract from G. tinctoria leaves with chemical constituents such as ellagic acid and quercetin derivatives suggests its application to prevent endothelial dysfunction and oxidative stress. The aim of this study was to provide evidence of the protective effect of this extract on endothelial function by reducing oxidative stress induced by high D-glucose and H2O2, as well as by stimulating nitric oxide (NO) levels in human umbilical vein endothelial cells (HUVECs). RESULTS: A methanolic extract with a high content of polyphenols (520 ± 30 mg gallic acid equivalents/g dry extract) was obtained from G. tinctoria leaves. Its main constituent was ellagic acid. The results of Ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays of the extract confirmed its antioxidant activity by inhibition pathway of radical species. The incubation of HUVECs with the extract decreased the apoptosis and reactive oxygen species (ROS) synthesis induced by high extracellular concentration of D-glucose or hydrogen peroxide. The extract increased endothelial NO levels and reduced vasoconstriction in human placental vessels. CONCLUSIONS: This study provides evidence about the antioxidant and endothelial protective properties of methanolic G. tinctoria leaf extract. The extract improves the availability of NO in HUVECs, inhibiting the production of ROS and vasoconstriction.


Asunto(s)
Humanos , Femenino , Embarazo , Extractos Vegetales/farmacología , Estrés Oxidativo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Peróxido de Hidrógeno , Antioxidantes/farmacología , Especies Reactivas de Oxígeno , Apoptosis , Polifenoles/farmacología
6.
J Agric Food Chem ; 67(42): 11616-11626, 2019 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-31542929

RESUMEN

Avocado peel, a byproduct from the avocado pulp industry, is a promising source of polyphenolic compounds. We evaluated the effect of a proanthocyanidin-rich avocado peel polyphenol extract (AvPPE) on the composition and metabolic activity of human fecal microbiota cultured for 24 h in a bioreactor in the presence of high protein (HP) amounts and the effect of the resulting culture supernatants (CSs) on HT-29Glc-/+ and Caco-2 cells. AvPPE decreased the HP-induced production of ammonia, H2S, propionate, and isovalerate and increased that of indole and butyrate. Microbiota composition was marginally affected by HP, whileAvPPE increased the microorganisms/abundance of phylum Actinobacteria, families Coriobacteriaceae and Ruminococcaceae, and genus Faecalibacterium. AvPPE failed to prevent the HP-induced decrease of HT-29Glc-/+ cell viability and energy efficiency but prevented the HP-induced alterations of barrier function in Caco-2 cells. Additionally, the genotoxic effect of the CSs upon HT-29Glc-/+ was attenuated by AvPPE. Therefore, AvPPE may be considered as a promising product for improving colonic homeostasis.


Asunto(s)
Colon/efectos de los fármacos , Homeostasis/efectos de los fármacos , Persea/química , Extractos Vegetales/farmacología , Polifenoles/farmacología , Proantocianidinas/farmacología , Amoníaco/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Butiratos/metabolismo , Células CACO-2 , Colon/microbiología , Dieta Rica en Proteínas , Heces/microbiología , Frutas/química , Microbioma Gastrointestinal/efectos de los fármacos , Humanos , Proantocianidinas/análisis
7.
Food Funct ; 10(7): 4022-4035, 2019 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-31218325

RESUMEN

The consumption of high-protein diets (HPDs) increases the flux of undigested proteins moving to the colon. These proteins are hydrolyzed by bacterial proteases and peptidases, releasing amino acids, which in turn are metabolized by the intestinal microbiota (IM) for protein synthesis and production of various metabolites that can exert positive or deleterious effects, depending on their concentrations, at the colonic or systemic level. On the other hand, proanthocyanidins are polymers of flavan-3-ols which cannot be absorbed at the intestinal level, accumulating in the colon where they are fermented by the IM producing metabolites that appear beneficial for colonocytes and also at the peripheral level. This study evaluated the effect of an avocado peel polyphenol extract (AvPPE) rich in proanthocyanidins on the production of cecal bacterial metabolites and microbiota composition in rats fed a HPD. Compared with the normal-protein (NP) group, HPD did not markedly affect the body weight gain of the animals, but increased the kidney weight. Additionally, the HPD induced a higher cecal concentration of ammonia (NH4+/NH3), hydrogen sulfide (H2S) and branched-chain fatty acids (BCFAs). The supplementation with AvPPE attenuated the production of H2S and increased the production of indole. On the other hand, the HPD affected the composition of the cecal microbiota, increasing the relative abundance of the genera Bacteroides and Lactobacillus, while decreasing Prevotella. The AvPPE counteracted the increase induced by the HPD on the genus Lactobacillus, and increased the relative abundance of [Prevotella]. Our results contribute towards explaining the health-promoting effects of proanthocyanidin-rich dietary foodstuffs including fruits and vegetables.


Asunto(s)
Aminoácidos/biosíntesis , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Dieta Rica en Proteínas , Microbioma Gastrointestinal/efectos de los fármacos , Persea/química , Extractos Vegetales/farmacología , Proantocianidinas/farmacología , Amoníaco , Animales , Peso Corporal , Ciego/metabolismo , Ciego/microbiología , Colon/microbiología , Ácidos Grasos Volátiles , Fermentación , Flavonoides/química , Frutas/química , Lactobacillus , Masculino , Modelos Animales , Tamaño de los Órganos , Polifenoles , Ratas , Ratas Wistar
8.
Amino Acids ; 50(6): 755-763, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29700653

RESUMEN

Hydrogen sulfide (H2S), a metabolic end product synthesized by the microbiota from L-cysteine, has been shown to act at low micromolar concentration as a mineral oxidative substrate in colonocytes while acting as an inhibitor of oxygen consumption at higher luminal concentrations (65 µM and above). From the previous works showing that polyphenols can bind volatile sulfur compounds, we hypothesized that different dietary proanthocyanidin-containing polyphenol (PACs) plant extracts might modulate the inhibitory effect of H2S on colonocyte respiration. Using the model of human HT-29 Glc-/+ cell colonocytes, we show here that pre-incubation of 65 µM of the H2S donor NaHS with the different polyphenol extracts markedly reduced the inhibitory effect of NaHS on colonocyte oxygen consumption. Our studies on HT-29 Glc-/+ cell respiration performed in the absence or the presence of PACs reveal rapid binding of H2S with the sulfide-oxidizing unit and slower binding of H2S to the cytochrome c oxidase (complex IV of the respiratory chain). Despite acute inhibition of colonocyte respiration, no measurable effect of NaHS on paracellular permeability was recorded after 24 h treatment using the Caco-2 colonocyte monolayer model. The results are discussed in the context of the binding of excessive bacterial metabolites by unabsorbed dietary compounds and of the capacity of colonocytes to adapt to changing luminal environment.


Asunto(s)
Colon/metabolismo , Frutas/química , Sulfuro de Hidrógeno/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Extractos Vegetales/farmacología , Polifenoles/farmacología , Proantocianidinas/farmacología , Línea Celular Tumoral , Colon/citología , Humanos , Extractos Vegetales/química , Proantocianidinas/química
9.
Rev Chilena Infectol ; 33(4): 433-437, 2016 Aug.
Artículo en Español | MEDLINE | ID: mdl-27905627

RESUMEN

INTRODUCTION: Pediculosis capitis is a public health problem with a high prevalence. The emergence of parasite resistance to conventional pediculicide is of great concern worldwide. OBJECTIVE: To develop alternatives pediculicide, effective and safe, based on the essential oil of Eucaliptus globulus. METHOD: Through bioassays active concentrations ranges of the essential oil were established, and proceeded to develop a standardized, stable, pharmaceutical form, evaluating its effects on our population. RESULTS: The results showed 100% effectiveness; short time of death, ovicidal action, activity on the adhesion of the egg, and low toxicity. DISCUSSION: In addition to great effect, the inability of the parasite to become resistant to the chemical composition of the essential oil makes this formulation an alternative to the problem of head lice solution.


Asunto(s)
Insecticidas/farmacología , Aceites Volátiles/farmacología , Pediculus/efectos de los fármacos , Animales , Bioensayo , Eucalyptus , Aceite de Eucalipto , Humanos , Monoterpenos/farmacología
10.
Rev. chil. infectol ; Rev. chil. infectol;33(4): 433-437, ago. 2016. graf, tab
Artículo en Español | LILACS | ID: biblio-830114

RESUMEN

Introduction: Pediculosis capitis is a public health problem with a high prevalence. The emergence of parasite resistance to conventional pediculicide is of great concern worldwide. Objective: To develop alternatives pediculicide, effective and safe, based on the essential oil of Eucaliptus globulus. Method: Through bioassays active concentrations ranges of the essential oil were established, and proceeded to develop a standardized, stable, pharmaceutical form, evaluating its effects on our population. Results: The results showed 100% effectiveness; short time of death, ovicidal action, activity on the adhesion of the egg, and low toxicity. Discussion: In addition to great effect, the inability of the parasite to become resistant to the chemical composition of the essential oil makes this formulation an alternative to the problem of head lice solution.


Introducción: La pediculosis capitis es un problema de salud pública con una alta prevalencia. La aparición de resistencia del parásito a los pediculicidas convencionales es de gran preocupación a nivel mundial. Objetivo: Desarrollar alternativas pediculicidas, efectivas y seguras, en base al aceite esencial de Eucaliptus globulus. Método: A través de bioensayos se establecieron rangos de concentraciones activas del aceite esencial, y se procedió al desarrollo de una forma farmacéutica, estandarizada, estable, evaluando sus efectos en nuestra población. Resultados: Los resultados mostraron 100% de efectividad; corto tiempo de muerte, acción ovicida, actividad sobre la adherencia del huevo, y baja toxicidad. Discusión: Además de la gran efectividad, la imposibilidad del parásito de adquirir resistencia a la composición química del aceite esencial hace de esta formulación una solución alternativa al problema de la pediculosis.


Asunto(s)
Humanos , Animales , Pediculus/efectos de los fármacos , Aceites Volátiles/farmacología , Insecticidas/farmacología , Bioensayo , Monoterpenos/farmacología , Eucalyptus , Aceite de Eucalipto
11.
J Agric Food Chem ; 64(18): 3574-83, 2016 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-27039931

RESUMEN

The protective effect of proanthocyanidin-containing polyphenol extracts from apples, avocados, cranberries, grapes, or proanthocyanidin microbial metabolites was evaluated in colonic epithelial cells exposed to p-cresol, a deleterious compound produced by the colonic microbiota from l-tyrosine. In HT29 Glc(-/+) cells, p-cresol significantly increased LDH leakage and decreased ATP contents, whereas in Caco-2 cell monolayers, it significantly decreased the transepithelial electrical resistance and increased the paracellular transport of FITC-dextran. The alterations induced by p-cresol in HT29 Glc(-/+) cells were prevented by the extracts from cranberries and avocados, whereas they became worse by extracts from apples and grapes. The proanthocyanidin bacterial metabolites decreased LDH leakage, ameliorating cell viability without improving intracellular ATP. All of the polyphenol extracts and proanthocyanidin bacterial metabolites prevented the p-cresol-induced alterations of barrier function. These results suggest that proanthocyanidin-containing polyphenol extracts and proanthocyanidin metabolites likely contribute to the protection of the colonic mucosa against the deleterious effects of p-cresol.


Asunto(s)
Bacterias/metabolismo , Cresoles/efectos adversos , Células Epiteliales/microbiología , Frutas/metabolismo , Microbioma Gastrointestinal , Extractos Vegetales/metabolismo , Polifenoles/metabolismo , Proantocianidinas/metabolismo , Adenosina Trifosfato/metabolismo , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Cresoles/metabolismo , Células Epiteliales/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología
12.
Phytother Res ; 28(11): 1637-45, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24853276

RESUMEN

In this work, the anti-Helicobacter pylori effect of an aqueous extract from dried leaves of Peumus boldus Mol. (Monimiaceae) was evaluated. This extract displayed high inhibitory activity against H. pylori urease. Therefore, in order to clarify the type of substances responsible for such effect, a bioassay-guided fractionation strategy was carried out. The active compounds in the fractions were characterized through different chromatographic methods (RP-HPLC; HILIC-HPLC). The fraction named F5 (mDP = 7.8) from aqueous extract was the most active against H. pylori urease with an IC50 = 15.9 µg gallic acid equivalents (GAE)/mL. HPLC analysis evidenced that F5 was composed mainly by catechin-derived proanthocyanidins (LC-MS and phloroglucinolysis). The anti-adherent effect of boldo was assessed by co-culture of H. pylori and AGS cells. Both the aqueous extract and F5 showed an anti-adherent effect in a concentration-dependent manner. An 89.3% of inhibition was reached at 2.0 mg GAE/mL of boldo extract. In conjunction, our results suggest that boldo extract has a potent anti-urease activity and anti-adherent effect against H. pylori, properties directly linked with the presence of catechin-derived proanthocyanidins.


Asunto(s)
Adhesión Bacteriana/efectos de los fármacos , Biflavonoides/farmacología , Catequina/farmacología , Helicobacter pylori/efectos de los fármacos , Peumus/química , Extractos Vegetales/farmacología , Proantocianidinas/farmacología , Ureasa/antagonistas & inhibidores , Adenocarcinoma , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Helicobacter pylori/enzimología , Humanos , Concentración 50 Inhibidora , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Polifenoles/química
13.
Bol. latinoam. Caribe plantas med. aromát ; 10(3): 265-280, mayo 2011. ilus, tab
Artículo en Español | LILACS | ID: lil-687016

RESUMEN

Chronic infection by Helicobacter pylori produce chronic gastritis leading to other more severe pathologies as peptic ulcer and gastric adenocarcinoma. New anti-H. pylori agents has been found in natural products, particularly polyphenols. The inhibition of enzymes such us urease appears to be an interesting strategy by which polyphenols could limit the colonization by H. pylori. From the exocarp of Persea americana (avocado fruit), we obtain a procyanidin-rich extract with a 77 percent of gallic acid equivalents (GAE). Such procyanidins derived from epicatechin. with a mean degree of polymerization DPm = 6.10. The antioxidant capacity was assessed by different methods as TEAC-DPPH, TEAC-CUPRAC, TEAC-FRAP, TEAC-crocin. The extract shown inhibitory activity against H. pylori urease with an IC50 = 1.02 ug GAE/mL. In order to obtain clusters of procyanidins with different molecular weights, avocado peel extract was fractioned. A clear relation between the molecular size of procyanidins and their urease inhibitory activity was observed.


La infección crónica por Helicobacter pylori produce gastritis crónica o patologías más severas como la úlcera péptica y adenocarcinoma gástrico. Nuevos agentes anti-H. pylori se han encontrado en los productos naturales, donde destacan los polifenoles. La inhibición de enzimas como la ureasa, resulta ser una estrategia interesante mediante la cual los polifenoles pueden limitar la colonización por H. pylori. A partir del epicarpio del fruto de Persea americana (palto) se obtuvo un extracto polifenólico (77 por ciento de EAG), rico en procianidinas derivadas de epicatequina, con un grado de polimerización DPm = 6.10. La capacidad antioxidante fue evaluada mediante TEAC-DPPH, TEAC-CUPRAC, TEAC-FRAP, TEAC-crocina. El extracto mostró una actividad inhibitoria de la ureasa de H. pylori con un IC50 = 1.02 ug EAG/mL. El fraccionamiento de las procianidinas permitió agruparlas según su peso molecular, observándose una clara relación entre su tamaño y la capacidad de inhibir la ureasa.


Asunto(s)
Antioxidantes/farmacología , Extractos Vegetales/farmacología , Helicobacter pylori , Persea/química , Ureasa/antagonistas & inhibidores , Polifenoles/farmacología , Ureasa
14.
Bol. latinoam. Caribe plantas med. aromát ; 10(6): 507-524, ene. 2011. tab, ilus
Artículo en Español | LILACS | ID: lil-618847

RESUMEN

The aim of this work was to identify an effective method to improve the rate and percentage of germination and the rooting of seeds and cuttings of Lepechinia chamaedryoides (Balb.) Epling. Morphological changes experienced by the seed during the germination process also were followed by microscopy. This research was conducted during 2009 and 2010 in the Faculty of Agronomy of the University of Concepción. Four germination tests were assayed: a) sulfuric acid scarification and further stratification, b) leaching of inhibitors with different water temperatures plus different concentrations of gibberellic acid, c) thermal scarification plus stratification and d) gibberellic acid application at different concentrations. The highest percentage of germination was obtained with thermal scarification and stratification. Vegetative propagation test consisted of different concentrations of indole butyric acid (IBA) applied to the stem base. Significant differences between treatments were not found. The morphological changes of the seed during the germination process were observed by scanning electron microscope (SEM). These findings allowed identifying characteristics of highly lignified pericarp.


Con el propósito de identificar un método efectivo para obtener un alto porcentaje de germinación y enraizamiento en semillas y estacas de Lepechinia chamaedryoides (Balb.) Epling y observar los cambios morfológicos que experimenta la semilla durante el proceso de germinación, se realizó esta investigación durante el año 2009 y 2010 en la Facultad de Agronomía de la Universidad de Concepción. Se efectuaron cuatro ensayos de germinación: a) escarificación con ácido sulfúrico y estratificación, b) lixiviación de inhibidores con agua a diferentes temperaturas más concentraciones de ácido giberélico, c) escarificación térmica más estratificación y d) aplicación de ácido giberélico, en diferentes concentraciones. El mayor porcentaje de germinación se obtuvo con el tratamiento de escarificación térmica y estratificación. Con respecto a la propagación vegetativa, se realizaron ensayos con diferentes concentraciones de ácido indolbutírico (IBA) aplicado a la base de las estacas, no observándose diferencias significativas entre tratamientos. Los cambios morfológicos de la semilla durante el proceso de germinación se observaron mediante Microscopio Electrónico de Barrido (MEB) lo que permitió identificar características anatómicas y estructurales de un pericarpio altamente lignificado.


Asunto(s)
Plantas Medicinales/crecimiento & desarrollo , Salvia/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Germinación , Lamiaceae , Microscopía Electrónica de Rastreo , Percolación , Salvia/ultraestructura , Semillas/ultraestructura , Temperatura , Estratificación Térmica , Factores de Tiempo
15.
J Agric Food Chem ; 57(17): 7743-9, 2009 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-19691323

RESUMEN

In the present work, the in vitro effect of a standardized extract of apple peel APPE (60% of total polyphenols; 58% of flavonoids; 30% of flavan-3-ols and procyanidins) was evaluated with regard to the viability of Helicobacter pylori. The cytotoxic effect of APPE on H. pylori was also evaluated through the resazurin assay and ATP level determination. In both assays, APPE showed an early cytotoxic effect, which was both concentration and time-dependent. Additionally, the effect of APPE on the intra and extracellular production of reactive oxygen species (ROS) was evaluated in human neutrophils stimulated by H. pylori, phorbol myristate acetate (PMA), and formyl-methionyl-leucyl-phenylalanine (fMLP). The extracellular and intracellular production of ROS was evaluated through chemiluminiscence with the isoluminol-horseradish peroxidase (HRP) and luminol-superoxide dismutase (SOD)-catalase systems, respectively. APPE showed an inhibiting effect on the multiplication of two H. pylori strains (ATCC 43504 and TX136) with a miminnum inhibitory concentration (MIC) value of 112.5 microg gallic acid equivalent (GAE)/mL. APPE inhibited the respiratory burst of neutrophils induced by H. pylori, PMA, and fMLP in concentration-dependent form. Interestingly, this effect was observed on both the interior and exterior of the neutrophil. This result suggests that apple peel polyphenols have an attenuating effect on the damage to gastric mucosa caused by neutrophil generated ROS and, particularly, when H. pylori displays its evasion mechanisms.


Asunto(s)
Frutas/química , Helicobacter pylori/efectos de los fármacos , Malus/química , Neutrófilos/efectos de los fármacos , Extractos Vegetales/farmacología , Estallido Respiratorio/efectos de los fármacos , Adenosina Trifosfato/análisis , Flavonoides/análisis , Helicobacter pylori/química , Helicobacter pylori/crecimiento & desarrollo , Humanos , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/fisiología , Fenoles/análisis , Extractos Vegetales/química , Polifenoles , Proantocianidinas/análisis , Acetato de Tetradecanoilforbol/farmacología
16.
J Agric Food Chem ; 57(2): 416-24, 2009 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-19128009

RESUMEN

Apple peel extracts and their fractions pooled according to their molecular size were prepared and evaluated for their inhibitory activity against Helicobacter pylori and Jack bean ureases. Urease Inhibitory effect of apple peel polyphenols (APPE) extracted from the Granny Smith variety was concentration-dependent and reversible. High molecular weight polyphenols (HMW) were more active against Helicobacter pylori and Jack bean ureases than low molecular weight polyphenols with IC50 values of 119 and 800 microg GAE/mL, respectively. The results suggest that monomeric compounds (mainly flavan-3-ols-and quercetin-O-glycosides) will not be implicated in the antiurease effect displayed by the apple peel polyphenolic extract. Thus, as a byproduct, apple peel is suitable for developing functional ingredients that could be useful for neutralizing an important Helicobacter pylori colonization factor.


Asunto(s)
Proteínas Bacterianas/antagonistas & inhibidores , Flavonoides/farmacología , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/enzimología , Malus/química , Fenoles/farmacología , Extractos Vegetales/farmacología , Ureasa/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Flavonoides/química , Peso Molecular , Fenoles/química , Extractos Vegetales/química , Polímeros/farmacología , Polifenoles , Ureasa/metabolismo
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