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1.
Environ Sci Technol ; 58(35): 15755-15765, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39163250

RESUMEN

Lithium, as an emerging contaminant, lacks sufficient information regarding its environmental and ecotoxicological implications within soil-plant systems. Employing maize, wheat, pea, and water spinach, we conducted a thorough investigation utilizing a multispecies, multiparameter, and multitechnique approach to assess the pollution characteristics and ecotoxicological effects of lithium. The findings suggested that lithium might persist in an amorphous state, altering surface functional groups and chemical bonds, although semiquantitative analysis was unattainable. Notably, lithium demonstrated high mobility, with a mild acid-soluble fraction accounting for 29.66-97.02% of the total, while a minor quantity of exogenous lithium tended to be a residual fraction. Plant analysis revealed that in 10-80 mg Li/kg soils lithium significantly enhanced certain growth parameters of maize and pea, and the calculated LC50 values for aerial part length across the four plant species varied from 173.58 to 315.63 mg Li/kg. Lithium accumulation in the leaves was up to 1127.61-4719.22 mg/kg, with its inorganic form accounting for 18.60-94.59%, and the cytoplasm fraction (38.24-89.70%) predominantly harbored lithium. Furthermore, the model displayed that growth stimulation might be attributed to the influence of lithium on phytohormone levels. Water spinach exhibited superior accumulation capacity and tolerance to lithium stress and was a promising candidate for phytoremediation strategies. Our findings contribute to a more comprehensive understanding of lithium's environmental behavior within soil-plant systems, particularly within the context of global initiatives toward carbon neutrality.


Asunto(s)
Litio , Contaminantes del Suelo , Suelo , Suelo/química , Contaminantes del Suelo/toxicidad , Ecotoxicología , Plantas/efectos de los fármacos
2.
Phytochem Anal ; 35(4): 903-922, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38403936

RESUMEN

INTRODUCTION: The safety and quality of many medicinally important herbs are compromised since farmers and small organizations are involved in the cultivation, aggregation, and primary processing of these herbs. Such organizations often lack adequate quality control facilities. To improve the safety and quality of herbal products, simple, rapid, and affordable quality control systems are required. OBJECTIVES: The aim of this study was to assess the suitability of microwave oven-drying for moisture content (MC) determination and sample preparation of herbs in small organizations. METHODS: Microwave oven-drying (720 W) and convective oven-drying at 105°C for MC determination were compared. The effects of three different drying methods (microwave oven-drying, low-temperature convective drying, and freeze-drying) on in vitro antioxidant and polyphenol oxidase (PPO) activity were determined, similarity analysis was conducted using HPLC signature spectra, and validation was performed with LC-MS focusing on one herb. RESULTS: Microwave oven-drying at 720 W significantly reduced the drying time (from hours to minutes), whereas the spatial variation of temperature in convective ovens set at 105°C can cause about 10% underestimation of MC. Microwave oven-drying showed similar macro-properties like freeze-drying and higher extractability (10%-20%) and in vitro antioxidant capacity (33%-66%) and lower PPO activity compared to low-temperature convective drying. HPLC signature spectra revealed strong similarity of soluble components between freeze-dried and microwave oven-dried herbs. LC-MS analysis demonstrated more common compounds between freeze-dried and microwave oven-dried Centella asiatica extracts, whereas convective tray-dried samples had fewer compounds common with samples obtained by freeze-drying or microwave oven-drying. CONCLUSIONS: Microwave oven-drying is rapid (tens of min) and shows small batch-to-batch variation compared to oven-drying at 105°C. The in vitro antioxidant assays and signature spectra can be used for assessing the source and purity or quality of a specific herb variety.


Asunto(s)
Antioxidantes , Desecación , Liofilización , Microondas , Plantas Medicinales , Control de Calidad , Plantas Medicinales/química , Antioxidantes/análisis , Antioxidantes/química , Desecación/métodos , Liofilización/métodos , Cromatografía Líquida de Alta Presión/métodos , Catecol Oxidasa/análisis
3.
Toxicol Ind Health ; 40(8): 441-464, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38748851

RESUMEN

The water extractability and acute aquatic toxicity of seven aliphatic diisocyanate-based prepolymer substances were investigated to determine if lesser reactivity of the aliphatic isocyanate groups, as well as increased ionization potential of the expected (aliphatic amine-terminated) polymeric hydrolysis products, would influence their aquatic behavior compared to that of previously investigated aromatic diisocyanate-based prepolymers. At loading rates of 100 and 1,000 mg/L, only the substances having log Kow ≤9 exhibited more than 1% extractability in water, and a maximum of 66% water extractability was determined for a prepolymer having log Kow = 2.2. For the more hydrophobic prepolymer substances (log Kow values from 18-37), water extractability was negligible. High-resolution mass spectrometric analyses were performed on the water-accommodated fractions (WAF) of the prepolymers, which indicated the occurrence of primary aliphatic amine-terminated polymer species having backbones and functional group equivalent weights aligned to those of the parent prepolymers. Measurements of reduced surface tension and presence of suspended micelles in the WAFs further supported the occurrence of these surface-active cationic polymer species as hydrolysis products of the prepolymers. Despite these characteristics, the water-extractable hydrolysis products were practically non-toxic to Daphnia magna. All of the substances tested exhibited 48-h EL50 values of >1,000 mg/L, with one exception of EL50 = 157 mg/L. The results from this investigation support a grouping of the aliphatic diisocyanate-based prepolymers as a class of water-reactive polymer substances having predictable aquatic exposure and a uniformly low hazard potential, consistent with that previously demonstrated for the aromatic diisocyanate-based prepolymers.


Asunto(s)
Isocianatos , Contaminantes Químicos del Agua , Animales , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Isocianatos/química , Isocianatos/toxicidad , Polímeros/química , Polímeros/toxicidad , Daphnia/efectos de los fármacos , Relación Estructura-Actividad , Poliuretanos/química , Poliuretanos/toxicidad
4.
Int J Inf Secur ; 23(1): 431-445, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39221453

RESUMEN

Zero-knowledge succinct non-interactive arguments of knowledge (zk-SNARKs) are the most efficient proof systems in terms of proof size and verification. Currently, Groth's scheme from EUROCRYPT 2016, Groth 16 , is the state-of-the-art and is widely deployed in practice. Groth 16 is originally proven to achieve knowledge soundness, which does not guarantee the non-malleability of proofs. There has been considerable progress in presenting new zk-SNARKs or modifying Groth 16 to efficiently achieve strong Simulation extractability, which is shown to be a necessary requirement in some applications. In this paper, we revise the Random oracle based variant of Groth 16 proposed by Bowe and Gabizon, BG18, the most efficient one in terms of prover efficiency and CRS size among the candidates, and present a more efficient variant that saves 2 pairings in the verification and 1 group element in the proof. This supersedes our preliminary construction, presented in CANS 2020 (Baghery et al. in CANS 20, volume 12579 of LNCS, Springer, Heidelberg. pp 453-461, 2020), which saved 1 pairing in the verification, and was proven in the generic group model. Our new construction also improves on BG18 in that our proofs are in the algebraic group model with Random Oracles and reduces security to standard computational assumptions in bilinear groups (as opposed to using the full power of the generic group model (GGM)). We implement our proposed simulation extractable zk-SNARK (SE zk-SNARK) along with BG18 in the Arkworks library, and compare the efficiency of our scheme with some related works. Our empirical experiences confirm that our SE zk-SNARK is more efficient than all previous simulation extractable (SE) schemes in most dimensions and it has very close efficiency to the original Groth 16 .

5.
Crit Rev Food Sci Nutr ; : 1-19, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37203963

RESUMEN

To achieve a more sustainable global food production, a shift from animal to plant protein based food is necessary. At the same time, these plant proteins are preferentially derived from side-streams of industrial processes. Wheat bran and germ represent two major side-streams of the wheat milling industry, and contain aqueous-phase soluble proteins with a well-balanced amino acid composition. To successfully use wheat bran and germ proteins in novel plant-based liquid and semi-solid foods, they need to (i) be rendered extractable and (ii) contribute functionally to stabilizing the food system. Prior heat treatment and the occurrence of intact cell walls are important barriers in this regard. Several strategies have been applied to overcome these issues, including physical processing and (bio)chemical modification. We here present a comprehensive, critical overview of the aqueous-phase extraction of protein from (modified) wheat bran and germ. Moreover, we discuss the functionality of the extracted protein, specifically in the context of liquid (foam- and emulsion-type) and semi-solid (gel-type) food applications. In each section, we identify important knowledge gaps and highlight several future prospects that could further increase the application potential of wheat bran and germ proteins in the food industry.

6.
J Sci Food Agric ; 103(10): 5039-5049, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36977630

RESUMEN

BACKGROUND: The wine sector is constantly evolving, in order to adapt to consumer tastes. The organoleptic characteristics in wines are the main factors to obtain quality wines. Proanthocyanidins (PAs) are responsible in an important way for positive aspects in quality wines, such as body and color stability in red wines, but they are also responsible for sensory characteristics that can be negative for their quality when found in excessive concentrations. One strategy to improve grapevines and wines is to obtain new varieties, so our research institute has been selecting some of them from direct crosses between Monastrell and other considered premium varieties such as Cabernet Sauvignon and Syrah. RESULTS: A quantitative analysis in grapes, seeds and wines was carried out during three consecutive seasons (2018, 2019 and 2020) in order to characterize PAs composition and concentration in the following new varieties: MC80 (Monastrell × Cabernet Sauvignon), MC98, MC4, MC18 and MS10 (Monastrell × Syrah). Other aspect to study was the extraction capacity of the different new varieties of PAs during maceration process into must/wine. CONCLUSION: In general, the results showed higher concentrations in PAs in most crosses for the three seasons studied compared to Monastrell variety. It was remarkable that a higher concentration of epigallocatechin was found in most of the wines elaborated with the crosses, being a positive aspect from an organoleptic point of view, since this compound provides softness to the wines. © 2023 Society of Chemical Industry.


Asunto(s)
Proantocianidinas , Vitis , Vino , Proantocianidinas/análisis , Vino/análisis , Vitis/química , Semillas/química , Sensación
7.
J Sci Food Agric ; 103(7): 3457-3467, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36727418

RESUMEN

BACKGROUND: Grapevine red blotch virus (GRBV) is the causal agent of grapevine red blotch disease and is known to delay grape ripening. However, grape cell-wall modifications during GRBV infection are largely unknown, even though the cell wall plays a large role in pathogenicity, viral interactions with host plants, and phenolic extractability during winemaking. Understanding the impact of GRBV infection on cell-wall metabolism is important for the development of potential mitigations strategies. In this study, high-throughput transcriptome sequencing was conducted on Vitis vinifera L. 'Merlot' grapes during ripening. The cell-wall composition, phenolic content, and phenolic extractability at two different commercial harvest points were also determined. RESULTS: Log fold changes indicated a strong induction in diseased grapes at harvest of several transcripts involved in cell-wall solubilization and degradation. However, these observations did not translate to changes in cell-wall composition at either harvest point in diseased grapes, potentially suggesting post-transcriptional regulation. Moderate induction of pectin methylesterase inhibitor transcripts and transcripts associated with pathogenesis-related proteins coincided with increases in pectin and soluble proteins in cell walls of diseased grapes at harvest. Both pectin and pathogenesis-related proteins are known to retain phenolic compounds during winemaking. CONCLUSION: Our study corroborates this finding when the percentage extractability of flavonols in wines was significantly lower when made from GRBV-infected fruit. These results suggest GRBV alters the grape cell walls, consequently decreasing phenolic extraction during winemaking. © 2023 Society of Chemical Industry.


Asunto(s)
Geminiviridae , Vitis , Vino , Vitis/química , Enfermedades de las Plantas , Vino/análisis , Pared Celular/química , Frutas/química , Fenoles/análisis , Geminiviridae/fisiología , Pectinas/análisis
8.
Environ Geochem Health ; 45(7): 4737-4760, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36928804

RESUMEN

Composting can turn organic waste into a valuable soil amendment that can improve physical, chemical, and biological soil quality. Compost amendments can also contribute to the remediation of areas anthropogenically degraded by metals. However, it is well known that compost, particularly self-produced compost, can show enrichment in metals. An experimental study was conducted to examine the short- and long-term distribution and the mobility of metals in soils amended with a self-produced compost when it was added alone or in combination with different doses of a natural zeolite to soil. The aim was also to study the interest of managing moderately metal-contaminated kitchen garden soils by assessing the chemical extractability, phytoavailability, and oral bioaccessibility of metals. When zeolite was added to compost alone, it had the tendency to better reduce extractability of Cd and Zn at 25%, and those of Pb at 15%. When the self-produced compost alone or in co-application with zeolite at these doses was applied to soils, the results showed (1) a decrease of NH4NO3-extractable Zn; (2) a reduction of Pb environmental availability, but not Pb bioaccessibility, and (3) an increase of ryegrass biomass. Nevertheless, the risk posed by the self-produced compost was minimal when applied at the proper rate (0.6% w/w). In the selected experimental conditions, the study recommends that self-produced compost be mixed with 15% zeolite to maximize vegetal biomass and minimize environmental risk. The question of sustainability of the results with repeated compost addition is also raised.


Asunto(s)
Compostaje , Metales Pesados , Contaminantes del Suelo , Zeolitas , Jardines , Contaminantes del Suelo/análisis , Metales/toxicidad , Suelo , Metales Pesados/análisis
9.
Bull Environ Contam Toxicol ; 111(5): 63, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37904061

RESUMEN

The risk assessment of heavy metals (HMs) in sewage sludge (SS) is essential before land application. Six HMs in nineteen SS collected in the Yangtze River Delta were analyzed to assess risks to environment, ecosystem, and human health. HMs concentrations were ranked in the order of Zn > Cu > Cr > Ni > Pb > Cd, with Cu, Zn, and Ni in a total of 16% of samples exceeding the legal standard. Zn showed greatest extractability according to EDTA-extractable concentrations. HMs in 16% of SS samples posed heavy contamination to the environment with Zn as the major pollutant. HMs in 26% of samples posed ecological risk to the ecosystem and Cd was the highest risky HM. The probabilistic health risk assessment revealed that HMs posed carcinogenic risks to all populations, but non-carcinogenic risks only to children. This work will provide fundamental information for land application of SS in this area.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Niño , Humanos , Aguas del Alcantarillado , Ecosistema , Monitoreo del Ambiente , Ríos , Cadmio , Contaminantes del Suelo/análisis , Medición de Riesgo , Metales Pesados/análisis , China
10.
Molecules ; 27(15)2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35956834

RESUMEN

In this study, we evaluated the extractability of three curcuminoids (curcumin, demethoxycurcumin, and bisdemethoxycurcumin) from turmeric powder in several solvents using high-performance liquid chromatography (HPLC) with the diode-array detection method. These solvents include water, milk (homogenized, 2% reduced fat, low fat, fat free, soy, almond, coconut, and milkadamia), and aqueous ethanols (0%, 4%, 10%, 20%, 30%, 40%, 50%, and 100%). Ambient water was able to extract only 0.55 mg/g of curcuminoids, whereas warm water extracted more than four-fold higher amounts (2.42 mg/g). Almond, coconut, and milkadamia milk were able to extract only small amounts of curcuminoids at ambient temperatures (0.01-0.07 mg/g). The extractability of curcuminoids in these milk types did not improve, even in warm conditions (0.08-0.37 mg/g). Whereas dairy and soy milk extracted 6.76-9.75 mg/g of curcuminoids under ambient conditions, their extractability increased significantly in warm conditions by 30-100% higher (11.7-14.9 mg/g). The solubility of curcuminoids also varied remarkably in different proportions of aqueous-alcohol mixtures. With 4% ethanol, only 1.7 mg/g of curcuminoids were extracted, and the amounts improved with the increase in ethanol content up to 50% (32.2 mg/g), while 100% ethanol extracted a similar amount as 50% ethanol (34.2 mg/g). This study suggests that the extractability of curcuminoids from turmeric will be dependent on the type of diets consumed with the turmeric supplements.


Asunto(s)
Curcumina , Extractos Vegetales , Curcuma/química , Curcumina/química , Diarilheptanoides , Etanol/química , Extractos Vegetales/química , Solventes/química , Agua/química
11.
Environ Geochem Health ; 44(4): 1317-1327, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34008142

RESUMEN

The phytostabilization of mine tailings requires a previous assessment of the effects of soil amendments on metal mobility. The goal of this work was to evaluate the response of metal availability (both labile and potentially available pools) to the addition of two organic amendments (a municipal waste biosolid and a tree biochar), separately and in combination, in a mine tailings substrate. For this purpose, a comprehensive comparison among several single extraction procedures and a sequential extraction procedure was performed. The effects on metals phytotoxicity were assessed through a germination test using seeds of Zygophyllum fabago. When evaluating the effect of the amendments in the labile metal pool, the biochar resulted effective in decreasing metal-extractable concentrations, especially for Cd, Mn and Zn. The treatment with biochar also showed better germination parameters (percentage of germinated seeds and sooner germination) than the rest of the unamended and amended treatments. The use of the municipal organic biosolid increased labile metal concentrations and potentially available metal pools assessed with EDTA and did not contribute to achieve better results of seed germination. Compared to the single biosolid treatment, the combination of biochar/biosolid modulated some labile metal concentrations and showed similar germination parameters to those obtained for the treatment amended only with biochar. This positive effect of biochar in modulating the soluble metal concentrations associated with certain urban/agricultural organic materials supported the suitability of using these combinations in field applications, although a higher rate of biochar application would be recommended to obtain a more beneficial effect.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Biosólidos , Carbón Orgánico , Metales Pesados/análisis , Suelo , Contaminantes del Suelo/análisis , Árboles
12.
Ecotoxicol Environ Saf ; 205: 111316, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33007600

RESUMEN

The interaction between multi-walled carbon nanotubes (MWCNTs) and soil heavy metals was rarely studied. With the convenience of detecting multiple metal elements by ICP-AES, this paper examined the potential effectiveness of MWCNTs on extractability of antimony (Sb) and cadmium (Cd) in contaminated soil. Three-step sequential extraction procedure, toxicity characteristic leaching procedure, bioaccessibility and CaCl2 single extraction were employed to evaluate Sb and Cd speciations and their extractabilities. According to our results, only at low Sb content level of 100 mg/kg, antimony bioavailability reduced with MWCNTs addition of 0.3% and 0.9% by 22.97% and 20.74%, respectively, which might due to the increase of adsorption point, nevertheless, the excess Sb(OH)6- was not adsorbed more efficiently. Secondly, due to the difference in effective specific surface area, only under the condition of high content level and MWCNTs addition of 0.1%, the mild acid-soluble fraction increased at most by 15.40% for Sb and 9.40% for Cd, respectively. However, in terms of TCLP-extractable Sb and Cd and CaCl2-extractable Sb and Cd, no significant, continuous, regular extractability pattern were found. Overall, MWCNTs were selective on extractability of soil heavy metals due to mechanisms of physical adsorption. This paper provides data reference for the interaction between MWCNTs and soil heavy metals extractability.


Asunto(s)
Cadmio/química , Nanotubos de Carbono/química , Contaminantes del Suelo/química , Adsorción , Antimonio , Disponibilidad Biológica , Contaminación Ambiental , Metales Pesados , Suelo
13.
Molecules ; 24(18)2019 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-31540067

RESUMEN

The effects of temperature and ethanol concentration on the kinetics of anthocyanin adsorption and desorption interactions with five cell wall materials (CWM) of different composition were investigated. Using temperatures of 15 °C and 30 °C and model wine with ethanol concentrations of 0% and 15% (v/v) over 120 min, the adsorption and desorption rates of five anthocyanin-glucosides were recorded in triplicate. Small-scale experiments were conducted using a benchtop incubator to mimic a single berry fermentation. Results indicate that more than 90% of the adsorption occurs within the first 60 min of the addition of anthocyanins to CWM. However, desorption appears to occur much faster, with maximum desorption being reached after 30 min. The extent of both adsorption and desorption was clearly dependent not only on temperature and ethanol concentration but also on the CWM composition.


Asunto(s)
Antocianinas/química , Pared Celular/química , Etanol/química , Frutas/química , Calor , Vitis/química , Glucósidos/química
14.
Ecotoxicol Environ Saf ; 161: 281-289, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29886315

RESUMEN

The aim of this study was to evaluate the use of drinking-water treatment residuals (DWTR) in the amendment of a soil affected by mining activities (Aljustrel mine, Portuguese sector of the Iberian Pyrite Belt), considering the effects on its chemical, biochemical and ecotoxicological characteristics. The DWTR had neutral characteristics (pH 6.7) and an organic matter (OM) content of 575 g kg-1 dry matter (DM), which makes them a potential amendment for the remediation of mine degraded soils, as they may correct soil acidity and reduce the extractable metal fraction. An incubation assay, with soil and DWTR, with or without lime, was carried out to test the doses to be used in the assisted-phytostabilization experiment. Based on the results obtained, the doses of DWTR used were the equivalent to 48, 96, and 144 t DM ha-1, with and without lime application (CaCO3 11 t DM ha-1). Agrostis tenuis Sibth was used as the test plant. Some amendments doses were able to improve soil characteristics (pH and OM content), to decrease metal extractability by 0.01 M CaCl2 (especially for Cu and Zn), and to allow plant growth, that did not occur in the non-amended soil. Copper, Pb and Zn concentrations in the plant material were lower than the maximum tolerable level for cattle feed, used as an indicator of risk of entry of those metals into the human food chain. The simultaneous application of DWTR (96 and 144 t ha-1), with lime, allowed a reduction in the mine soil ecotoxicity, as evaluated by some lethal and sub-lethal bioassays, including luminescence inhibition of Vibrio fischeri, Daphnia magna acute immobilization test, mortality of Thamnocephalus platyurus, and 72-h growth inhibition of the green microalgae Pseudokirchneriella subcapitata. However, DWTR were unable to increase soil microbial activity, evaluated by dehydrogenase activity, an important soil-health indicator. Also, OM content and NKjeldahl, concentrations increased slightly but remained low or very low (P and K extractable concentrations were not affected). In general, the bioassays highlighted a decrease in soil ecotoxicity with the presence of lime and DWTR (144 t DM ha-1). In conclusion, DWTR are recommended to amend acidic soils, with high concentrations of trace elements, but an additional application of organic or mineral fertilizers should be considered.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Fertilizantes/análisis , Minería , Suelo/química , Residuos/análisis , Purificación del Agua , Aliivibrio fischeri/efectos de los fármacos , Animales , Daphnia/efectos de los fármacos , Ecotoxicología , Metales Pesados/análisis , Metales Pesados/toxicidad , Desarrollo de la Planta/efectos de los fármacos , Portugal , Eliminación de Residuos , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad
15.
Sensors (Basel) ; 18(8)2018 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-30049946

RESUMEN

Near infrared hyperspectral data were collected for 200 Syrah and Tempranillo grape seed samples. Next, a sample selection was carried out and the phenolic content of these samples was determined. Then, quantitative (modified partial least square regressions) and qualitative (K-means and lineal discriminant analyses) chemometric tools were applied to obtain the best models for predicting the reference parameters. Quantitative models developed for the prediction of total phenolic and flavanolic contents have been successfully developed with standard errors of prediction (SEP) in external validation similar to those previously reported. For these parameters, SEPs were respectively, 11.23 mg g-1 of grape seed, expressed as gallic acid equivalents and 4.85 mg g-1 of grape seed, expressed as catechin equivalents. The application of these models to the whole sample set (selected and non-selected samples) has allowed knowing the distributions of total phenolic and flavanolic contents in this set. Moreover, a discriminant function has been calculated and applied to know the phenolic extractability level of the samples. On average, this discrimination function has allowed a 76.92% of samples correctly classified according their extractability level. In this way, the bases for the control of grape seeds phenolic state from their near infrared spectra have been stablished.

16.
J Environ Manage ; 217: 297-304, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29614478

RESUMEN

Excavated soils with low-level As contamination obtained from construction projects during city development have been of great concern in Japan. Water-extractable As represents the most easily mobilized and ecotoxicologically relevant fraction in the soil environment. In the present study, the water-extractability of As in excavated alkaline urban soils was assessed using sequential leaching tests (SLTs) with a focus on the effects of test parameters. In addition, the potentially water-leachable As over an extremely long period was assessed using the pollution potential leaching index (PPLI), from which one can estimate the number of extractions required to reduce the As in the cumulative leachates to below the Japanese environmental standard (10 µg L-1). Total As concentrations varied from 6.75 to 79.4 mg kg-1, and As was continuously detectable among replicate SLT experiments. The water-extractable As obtained in the first step of the SLT accounted for 0.41%-7.60% of total As (average: 2.36%), while the cumulative released As in the SLTs corresponded to 1.30%-21.6% of the total (average: 10.6%). The variability of the water-soluble fractions was sensitive to the test conditions. The shaking time at each SLT step had the largest effect on the As water-extractability; followed by sample storage, shaking speed and shaking interruption. A longer shaking time in the standard leaching test of excavated soils is suggested for regulatory purposes in Japan. The use of the PPLI concept for quick estimation of the potential As leachability from excavated soils was supported by the good reproducibility of PPLI results obtained from SLTs under different test parameters.


Asunto(s)
Arsénico/química , Contaminantes del Suelo , Agua , Arsénico/aislamiento & purificación , Japón , Reproducibilidad de los Resultados , Suelo
17.
Environ Monit Assess ; 190(6): 345, 2018 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-29761238

RESUMEN

The availability of cadmium (Cd) for plants and its impact in the environment depends on Cd sorption in soil colloids. The study of Cd sorption in soil and its fractionation is an interesting tool for the evaluation of Cd affinity with soil pools. The objective with this study was to evaluate Cd sorption and desorption in tropical soils with variable charge (three Oxisols), in a Mollisol and in two Entisols with diverse physical, chemical, and mineralogical attributes. We used a thermodynamic approach to evaluate Cd sorption and performed a chemical fractionation of Cd in the six soils. Data from Cd sorption fit the Langmuir model (r > 0.94), and the sorption capacity ranged from 0.33 to 11.5 mmol kg-1. The Gibbs standard free energy was positively correlated to Cd sorption capacity (r = 0.74, except for the Quartzipsamments), and it was more favorable in soils with great sorption capacity. Distribution of Cd among fractions was not affected (t test, α = 0.05) by initial concentration, and there was a predominance of Cd extractable in 0.1 mol L-1 CaCl2.


Asunto(s)
Cadmio/química , Contaminantes del Suelo/química , Adsorción , Brasil , Cadmio/análisis , Fraccionamiento Químico , Monitoreo del Ambiente , Concentración de Iones de Hidrógeno , Contaminantes del Suelo/análisis , Termodinámica
18.
J Sci Food Agric ; 97(14): 4835-4846, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28382623

RESUMEN

BACKGROUND: Double maturation raisonnée (DMR) is a potential canopy measure that affects grape and wine composition. The aim of this work was to study for the first time the DMR impact on the physical, biochemical and sensorial characteristics of the berries and wines of Merlot, one of the world's fastest-expanding grapevine varieties. RESULTS: DMR significantly increased the content of soluble solids (1.2-fold), free amino nitrogen (1.8-fold) and acidity in berries but decreased the weight of 100 berries on harvest (approx. 28%). Irrespective of the vintage, DMR-treated grapes had a significantly higher content of non-astringent tannins (0.73-0.78 mg L-1 ) and anthocyanin extractability (34.7-36.4%) but a lower index of astringency (31.2-33.7) when compared to the control. Consequently, the DMR wines achieved higher alcohol, total acidity and extract, hydroxycinnamic acids, flavanol and flavonol contents, whereas the content of anthocyanins was similar to that of the control. Sensorial evaluation showed that DMR wines were not rated higher and would not be appreciated more than control wines. CONCLUSION: Changes in berries during DMR altered the wine characteristics only in terms of primary metabolites. A reduced accumulation of phenolics, especially anthocyanin content, in the berry skin of DMR-treated grapes was not reflected in their presence in wines. To the best of our knowledge, this is the first paper that has reported an impact of DMR on the grape and wine composition of Merlot, as one of the most promising red varieties. © 2017 Society of Chemical Industry.


Asunto(s)
Producción de Cultivos/métodos , Frutas/química , Vitis/química , Vino/análisis , Antocianinas/análisis , Antocianinas/metabolismo , Aromatizantes/análisis , Aromatizantes/metabolismo , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Hojas de la Planta/química , Hojas de la Planta/crecimiento & desarrollo , Polifenoles/análisis , Polifenoles/metabolismo , Vitis/crecimiento & desarrollo , Vitis/metabolismo
19.
Int J Food Sci Nutr ; 66(3): 282-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25690928

RESUMEN

Broccoli (Brassica oleracea L. var. Italica) is largely consumed all over the world and has a high economic importance. Likewise, broccoli contains high levels of glucosinolates, carotenoids and total phenols, which are related with the prevention of chronic diseases. The present project's objective was to evaluate the effect of industrial freezing on the stability of bioactive molecules in seven commercial broccoli cultivars (Tlaloc®, Endurance®, Florapack®, Domador®, Steel®, Iron Man® and Avenger®). In general, industrial freezing increased the extractability of total glucosinolates, whereas total phenols remained constant in most broccoli cultivars. Likewise, broccoli subjected to industrial freezing showed higher levels of total carotenoids (∼60-300% higher) as compared with fresh broccoli. Results suggest that bioactive compounds in frozen broccoli would be more bioavailable than in raw.


Asunto(s)
Antioxidantes/análisis , Brassica/química , Carotenoides/análisis , Manipulación de Alimentos/métodos , Congelación , Glucosinolatos/análisis , Fenoles/análisis , Disponibilidad Biológica , Brassica/clasificación , Humanos , Especificidad de la Especie , Verduras/química
20.
J Food Sci Technol ; 52(3): 1705-11, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25745244

RESUMEN

Whole flours of sorghum cultivars Dabar, WadAhmed and Karamaka were irradiated and then fermented and/or cooked. Tannin and phytic acid contents were assayed for all treatments. Traditional processings (fermentation and cooking) were significantly (P ≥ 0.05) decreased tannin and phytate of the cultivars and further reduction was observed when the flour was irradiated before processing for all cultivars. Radiation process alone had no great effect on tannin and phytate contents but when followed by traditional processing the reduction level was significant (P ≥ 0.05) for all cultivars. Radiation alone had no significant (P ≥ 0.05) effect in increment of total and extractable calcium (Ca). However, radiation followed by fermentation and/or cooking significantly (P ≥ 0.05) increased both total and extractable Ca. Total phosphorus (P) was not significantly (P ≥ 0.05) increased at all levels of radiation and/or processing but the extractable P was increased. Total iron (Fe) was not affected by radiation and/or processings but the extractable Fe was increased significantly (P ≥ 0.05) with the radiation dose for all cultivars.

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