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1.
Food Chem ; 444: 138684, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38359701

RESUMEN

A research platform for food authentication was set up by combining stable isotope ratio analysis, metabolomics by gas and liquid mass-spectrometry and NMR investigations, chemometric analyses for food excellences. This multi-analytical approach was tested on samples of elephant garlic (Allium ampeloprasum L.), a species belonging to the same genus of common garlic (Allium ampeloprasum L.), mainly produced in southern Tuscany-(Allium ampeloprasum). The isotopic composition allowed the product to be geographically characterized. Flavonoids, like (+)-catechin, cinnamic acids, quercetin glycosides were identified. The samples showed also a significant amount of dipeptides, sulphur-containing metabolites and glutathione, the latter of which could be considered a molecular marker of the analyzed elephant garlic. For nutraceutical profiling to reach quality labels, extracts were investigated in specific biological assays, displaying interesting vasorelaxant properties in rat aorta by mediating nitric oxide release from the endothelium and exhibited positive inotropic and negative chronotropic effects in rat perfused heart.


Asunto(s)
Allium , Ajo , Animales , Ratas , Ajo/química , Allium/química , Cebollas/química , Antioxidantes/análisis , Suplementos Dietéticos , Italia
2.
Foods ; 9(5)2020 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-32375293

RESUMEN

Unripe grapes are a potential source of bioactive compounds which can exert antioxidant and antimicrobial activity. However, very little information is available about the composition of unripe grapes extracts and their extraction techniques. This study aims to evaluate the recovery of bioactive compounds and the antioxidant activity of the extract from unripe Sangiovese grapes obtained at an industrial-scale and the composition of the extract during processing. The extraction yield was approximately 75%. During the extraction, the total phenol (TP), antioxidant activity (AA) total anthocyanin (TAnt), pantothenic acid and choline content significantly increased. High concentrations of TP (2522 mgCATeq/L), AA (8227 µmolTEAC/L) and total water-soluble vitamins (1397 µg/L) were reached at the end of process. The antioxidant activity of the extract was positively correlated with all the phenol compounds and the highest correlations were found with procyanidin B1 (r = 0.994; p-value < 0.004), procyanidin B2 (r = 0.989; p-value < 0.004), kaempferol 3-O-glucoside (r = 0.995; p-value < 0.004) and quercetin 3-O-hexoside (r = 0.995; p-value < 0.071). Our findings contribute to the knowledge of the bioactive composition of unripe grapes. An efficient industrial-scale "green" extraction method, ready to be transferred to the wine sector, was developed to obtain a safe extract with a high concentration of bioactive compounds.

3.
Antioxidants (Basel) ; 7(2)2018 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-29419774

RESUMEN

The wine industry is well known for its production of a large amount of wastes and by-products. Among them, unripe grapes from thinning operations are an undervalued by-product. Grapes are an interesting source of natural antioxidants such as flavonoids, non-flavonoids and stilbenes. A potential strategy to exploit unripe grapes was investigated in this study. Juice from unripe grapes, v. Sangiovese, was obtained by an innovative technique of solid-liquid extraction without the use of solvents. The juice was dried by a spray-drying technique with the addition of arabic gum as support to obtain powder; juice and powder were characterized for antioxidant activity, phenolic concentration and profile. Phenolic acids, flavonols, flava-3-ols, procyanidins and resveratrol were detected in the juice and powder. The powder was used as anti-browning additive in white wine to test the potential re-use of the unripe grapes in the wine industry. The results indicated that the antioxidant complex from unripe grapes contributed to increasing the anti-browning capacity of white wine. Other applications, such as food and nutraceutical products development, can be considered for the antioxidant complex extracted from unripe grapes. In conclusion, the method proposed in this study may contribute to the exploitation of unripe grapes as a by-product of the winemaking process.

4.
Mar Pollut Bull ; 115(1-2): 465-468, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-27894725

RESUMEN

Growth of the aquaculture industry has triggered the need for research into the potential environmental impact of chemicals used by salmon farms to control diseases. In this study, the antiparasitic pesticides emamectin benzoate (EB), diflubenzuron (DI), teflubenzuron (TE), and cypermethrin (CP) were measured in sediments near salmon cages in southern Chile. Concentrations for EB were between 2.2 and 14.6ngg-1, while the benzoylphenyl ureas DI and TE were detected in the ranges of 0.1 to 1.2ngg-1 and 0.8 to 123.3ngg-1, respectively. These results were similar to data reported for the Northern Hemisphere. On the other hand, the pyrethroid CP was detected in higher concentrations, ranging from 18.0 to 1323.7ngg-1. According to reported toxicity data, this range represents a potential risk for benthic invertebrates. This report is the first baseline attempt at assessing antiparasitic pesticide levels in the Chilean Patagonia.


Asunto(s)
Antiparasitarios/análisis , Acuicultura , Sedimentos Geológicos/química , Salmón , Animales , Benzamidas/análisis , Chile , Diflubenzurón/análisis , Ivermectina/análogos & derivados , Ivermectina/análisis , Plaguicidas/análisis , Piretrinas/análisis
5.
Int J Endocrinol ; 2013: 510703, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23710174

RESUMEN

Significant evidence supports that many endocrine disrupting chemicals could affect female reproductive health. Aim of this study was to compare the internal exposure to bisphenol A (BPA), perfluorooctane sulphonate (PFOS), perfluorooctanoic acid (PFOA), monoethylhexyl phthalate (MEHP), and di(2-ethylhexyl) phthalate (DEHP) in serum samples of 111 infertile women and 44 fertile women. Levels of gene expression of nuclear receptors (ER α , ER ß , AR, AhR, PXR, and PPAR γ ) were also analyzed as biomarkers of effective dose. The percentage of women with BPA concentrations above the limit of detection was significantly higher in infertile women than in controls. No statistically significant difference was found with regard to PFOS, PFOA, MEHP and DEHP. Infertile patients showed gene expression levels of ER α , ER ß , AR, and PXR significantly higher than controls. In infertile women, a positive association was found between BPA and MEHP levels and ER α , ER ß , AR, AhR, and PXR expression. PFOS concentration positively correlated with AR and PXR expression. PFOA levels negatively correlated with AhR expression. No correlation was found between DEHP levels and all evaluated nuclear receptors. This study underlines the need to provide special attention to substances that are still widely present in the environment and to integrate exposure measurements with relevant indicators of biological effects.

6.
Gynecol Endocrinol ; 29(5): 444-7, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23347089

RESUMEN

Several studies report that endocrine disrupting chemicals (EDC) able to interfere with endocrine homeostasis may affect women's reproductive health. We analyzed EDC serum levels and nuclear receptors (NRs) expression in order to have an indication of the internal dose of biologically active compounds and a measurement of indicators of their effects, as a result of the repeated uptake from environmental source. The percentage of patients with detectable bisphenol A (BPA) concentrations was significantly higher in the infertile patients compared with fertile subjects. No significant difference was found between the groups with regard to perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), mono-ethylhexyl phthalate (MEHP) and di-(2-ethylhexyl) phthalate (DEHP) concentrations. Among infertile women, the mean expression of estrogen receptor alpha (ERα) and beta (Erß), androgen receptor (AR) and pregnane X receptor (PXR) was significantly higher than fertile patients. The mean expression of aryl hydrocarbon receptor (AhR) and peroxisome proliferator-activated receptor gamma (PPARγ) did not show significant differences between two groups. Patients with endometriosis had higher levels of PPARγ than all women with other causes of infertility. This study led further support to EDC exposure as a risk factor for women's fertility.


Asunto(s)
Disruptores Endocrinos/efectos adversos , Infertilidad Femenina/inducido químicamente , Receptores Citoplasmáticos y Nucleares/metabolismo , Adulto , Estudios de Casos y Controles , Disruptores Endocrinos/sangre , Femenino , Humanos , Infertilidad Femenina/sangre , Leucocitos Mononucleares/metabolismo , Embarazo
7.
J Hazard Mater ; 194: 135-43, 2011 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-21871720

RESUMEN

Exposure to mercury is often assessed by the measurement of molecular and biochemical antioxidant defences against an excessive production of reactive oxygen species. Here we examined some selected biomarkers of oxidative stress in the earthworm Lumbricus terrestris short- (2d) and long-term (44 d) exposed to Hg-contaminated soils (up to 1287 mg/kg dry wt). This level of Hg exposure did not cause earthworm mortality, however it yielded organisms to a situation of oxidative stress which was evidenced by the time-dependent responses of biomarkers. The reduced to oxidized glutathione ratio was a sensitive and early biomarker of Hg exposure, although the glutathione reductase activity back returned their normal physiological concentrations. Metallothioneins and total glutathione seemed to have a significant role in reducing Hg-induced oxidative stress when exposure to Hg prolonged up to 44 d. We combined biomarker responses into an integrate biomarker index which positively correlated with the Hg concentrations measured in the postmitochondrial fraction of the earthworm muscle, and with the available Hg fraction in soil. Current results suggest that glutathione redox cycle can be a complementary tool in the exposure and effect assessment of Hg-polluted soils.


Asunto(s)
Mercurio/toxicidad , Oligoquetos/metabolismo , Estrés Oxidativo/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Biomarcadores/metabolismo , Glutatión/metabolismo , Glutatión Reductasa/metabolismo
8.
Int J Antimicrob Agents ; 34(1): 50-9, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19386474

RESUMEN

Rubus spp. (Rosaceae) provide extracts used in traditional medicine as antimicrobial, anticonvulsant, muscle relaxant and radical scavenging agents. Resistance to antibiotics used to treat Helicobacter pylori infection as well as their poor availability in developing countries prompted us to test the antimicrobial activity of Rubus ulmifolius leaves and isolated polyphenols against two H. pylori strains with different virulence (CagA+ strain 10K and CagA(-) strain G21). The antioxidant activity (TEAC values) of the tested compounds ranged from 4.88 (gallic acid) to 1.60 (kaempferol), whilst the leaf extract gave a value of 0.12. All the isolated polyphenols as well as the leaf extract showed antibacterial activity against both of the H. pylori strains. The minimum bactericidal concentrations (MBCs) of the extract for H. pylori strains G21 and 10K, respectively, were 1200 microg/mL and 1500 microg/mL after 24h of exposure and 134 microg/mL and 270 microg/mL after 48 h exposure. Ellagic acid showed very low MBC values towards both of the H. pylori strains after 48 h (2 microg/mL and 10 microg/mL for strains G21 and 10K, respectively) and kaempferol toward G21 strain (MBC=6 microg/mL). A relationship between antimicrobial activity and antioxidant capacity was found only for H. pylori strain G21 CagA(-) strain.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Helicobacter pylori/efectos de los fármacos , Extractos Vegetales/farmacología , Hojas de la Planta/química , Rosaceae/química , Secuencia de Aminoácidos , Antibacterianos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Flavonoides/aislamiento & purificación , Flavonoides/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana , Datos de Secuencia Molecular , Fenoles/aislamiento & purificación , Fenoles/farmacología , Extractos Vegetales/aislamiento & purificación , Polifenoles , Factores de Tiempo
9.
Mar Environ Res ; 65(4): 349-57, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18281086

RESUMEN

The present paper assesses the use of the supralittoral amphipod Talitrus saltator as a bioindicator of the effects of human trampling on the supralittoral sandy band. Samplings in delimited areas were carried out at sites subjected to different human impact. The results showed a strong negative correlation between the number of swimmers and the sandhopper population density, while there was no clear relationship between sandhopper abundance and the other factors considered: granulometry, compactness and organic carbon content of the sand, and trace metal contents in the sand and sandhoppers. A field test of trampling conducted in a confined space showed its direct negative effect on sandhopper survival. However, trace metal analysis confirmed the ability of T. saltator to bioaccumulate some elements (Hg, Zn, Cu, Cd). Our study demonstrates that T. saltator is a good bioindicator of human impact in the supralittoral zone of sandy shores.


Asunto(s)
Anfípodos/fisiología , Playas , Ecosistema , Actividades Humanas , Dióxido de Silicio , Caminata , Animales , Carbono/análisis , Humanos , Metales Pesados/análisis , Tamaño de la Partícula , Densidad de Población , Dióxido de Silicio/química , Análisis de Supervivencia
10.
Environ Sci Technol ; 39(21): 8150-5, 2005 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-16294848

RESUMEN

Mercury emitted by anthropogenic and natural sources occurs in the atmosphere mostly in the gaseous elemental form, which has a long lifetime in tropical and temperate regions. Once deposited in terrestrial and aquatic ecosystems the metal is partly re-emitted into the air, thus assuming the characteristics of global pollutants such as persistent volatile chemicals. In polar regions, during and after the sunrise, the photochemically driven oxidation of gaseous Hg by reactive halogens may result in areas of greatly enhanced Hg deposition. Mercury concentrations in soils, lichens, and mosses collected in a stretch between 74 degrees 30' S and 76 degrees 00' S, in ice-free coastal areas of Victoria Land facing the Terra Nova Bay coastal polynya, were higher than typical Antarctic baselines. The finding of enhanced Hg bioaccumulation in Antarctic terrestrial ecosystems facing a coastal polynya strongly supports recent speculations on the role of ice crystals ("frost flowers") growing in polynyas as a dominant source of sea salt aerosols and bromine compounds, which are involved in springtime mercury depletion events (MDEs). These results raise concern aboutthe possible environmental effects of changes in regional climate and sea ice coverage, and on the possible role of Antarctica as a sink in the mercury cycle.


Asunto(s)
Ecosistema , Mercurio/análisis , Contaminantes del Suelo/análisis , Regiones Antárticas , Líquenes/química , Oxidación-Reducción
11.
Environ Pollut ; 136(2): 253-66, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15840533

RESUMEN

Semi-volatile organochlorine compounds (OC) were analyzed in remote Andean soils and lake sediments. The sampling sites covered a wide latitudinal gradient from 18 degrees S to 46 degrees S along Chile and an altitudinal gradient (10-4500 m). The concentrations were in the order of background levels, involving absence of major pollution sources in the high mountain areas. Significant correlations were found between log-transformed concentrations of hexachlorobenzene, alpha- and gamma-hexachlorocyclohexane in soils and total organic content (TOC). In addition, TOC-normalized concentrations of the most volatile OC showed a significant linear dependence with air temperature. This good agreement points to temperature as a significant factor for the retention of long range transported OC in remote ecosystems such as the Andean mountains, although other variables should not be totally excluded. The highest concentrations of OCs were achieved in the sites located at highest altitude and lowest temperature of the dataset.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/análisis , Hidrocarburos Clorados/análisis , Contaminantes del Suelo/análisis , Altitud , Chile , Agua Dulce , Temperatura
12.
Chemosphere ; 58(3): 271-8, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15581930

RESUMEN

The major organochlorine (OC) pollutants, i.e. pentachlorobenzene (PCBz), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), polychlorobiphenyls (PCBs) and DDTs have been analyzed in soils and mosses from coastal areas of Victoria Land (70-80 degrees S, 160-170 degrees E). PCBs (23-34 ng g(-1) dry wt.) and PCBz (0.38-1.3 ng g(-1) dry wt.) were the dominant OCs in mosses and soils, respectively. In general, the concentrations of OC in soils, i.e. HCB (0.034-0.17 ng g(-1) dry wt.), PCBs (0.36-0.59 ng g(-1) dry wt.) and 4,4'-DDE (0.053-0.086 ng g(-1) dry wt.), range among the lowest reported in remote regions. These concentrations exhibited high correlation coefficients when represented vs. total organic carbon (TOC) which is consistent with the general correlation between OC and TOC in soils from remote areas recently observed (Meijer, S.N., Ockenden, W.A., Seetman, A., Breivik, K., Grimalt, J.O., Jones, K.C., 2003. Global distribution and budget of PCBs and HCB in background surface soils: implications for sources and environmental processes. Environ. Sci. Technol. 37, 667-672). Statistically significant dependences between reciprocal of temperature and log-transformed concentrations of HCB and 4,4'-DDE in mosses and alpha-HCH in soils have been found. These observations provide further data illustrating that temperature is a major factor determining the planetary scale distribution and accumulation of OCs giving additional ground to the general validity of the global distillation effect for description of planetary OC distribution.


Asunto(s)
Briófitas/química , Contaminantes Ambientales/análisis , Hidrocarburos Clorados/análisis , Bifenilos Policlorados/análisis , Contaminantes del Suelo/análisis , Regiones Antárticas , Monitoreo del Ambiente , Temperatura
13.
Environ Sci Technol ; 38(20): 5386-92, 2004 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-15543741

RESUMEN

Organochlorine compounds (OC), namely pentachlorobenzene, hexachlorobenzene, hexachlorocyclohexanes, polychlorobiphenyls (PCBs), and DDTs, have been studied in mosses distributed over three altitude gradients of the Andean mountains in Chile at 18 degrees S (3200-4500 m above sea level), 37 degrees S (345-1330 m), and 45 degrees S (10-700 m). The observed concentrations range among the lowestvalues ever reported in remote sites, but they are still higher than those found in previously studied Antarctic areas. The log transformed OC concentrations show a significant linear dependence from reciprocal of temperature independently of the origin of the compounds, e.g. industrial, agricultural, or mixed. In the case of the more volatile OC these correlations involve variance percentages higher than 50%. This good agreement gives further ground to temperature as the driving factor for the retention of long-range transported OC in remote ecosystems, including those in the southern hemisphere such as the Andean mountains. In the context of the samples selected for study, the temperature dependences in the areas of similar latitude are related to altitude. Thus, all OC in the highest altitude gradient (18 degrees S) and most compounds in the other two profiles (37 degrees S and 45 degrees S) exhibit higher concentrations with decreasing annual average temperature and thus increase with elevation above sea level. However, theoretical examination of the exponential equation relating OC concentrations to reciprocal of absolute temperatures shows that besides the temperature differences between highest and lowest elevation, the most relevant factor determining the OC concentration gradients is the lowest temperature value of each altitudinal series. That is, the point at highest elevation.


Asunto(s)
Contaminantes Atmosféricos/análisis , Briófitas/química , Hidrocarburos Clorados/análisis , Movimientos del Aire , Chile , Monitoreo del Ambiente , Fenómenos Geológicos , Geología , Temperatura
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