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1.
Plants (Basel) ; 12(24)2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38140506

RESUMEN

Red grapes are rich in phytochemicals such as phenolics and flavonoids, which are strongly correlated with their antioxidant activity. Thus, grapes as-harvested and grape extracts, especially those obtained from their seeds and pulp, have been reported to have health benefits, and accordingly, grapes and their derivatives are considered potential functional food ingredients. The total phenolic content, total flavonoid content, and the antioxidant activity of skin, pulp, and seeds of four grape varieties grown both in conventional and organic vineyards were examined in this study. Phytochemical characteristics of one native Romanian variety, Feteasca Neagra, were compared with data measured for three red grape varieties more commonly cultivated worldwide (Merlot, Pinot Noir, and Muscat Hamburg). It was found that the seeds of the Pinot Noir variety grown in an organic system contained the highest total phenolics of 169.53 ± 7.32 mg gallic acid equivalents/g and the highest total flavonoid content of 388.25 ± 10.72 mg quercetin equivalents/g, values corresponding to high antioxidant activity (312.84 ± 12.81 mg ascorbic acid equivalents/g). The total flavonoid content in the hydroalcoholic extracts obtained from seeds of Pinot Noir (organic vineyard) was around 24.5-fold higher than that of the skin of Pinot Noir (conventional vineyard). Experiments showed that seeds of all four tested grape varieties are good sources of total flavonoids, not only of total phenolics. When referring to the organic vineyard, the skin and pulp grapes showed good results for the total phenolic content. The antioxidant activities of the hydroalcoholic extracts were well-correlated with the total phenolic content and total flavonoid content. Lower values of these parameters were found for extracts obtained from skin and pulp than for those obtained from seeds of the same grape variety regardless of the culture management system (organic/conventional). Data mining techniques such as regression analysis, principal component analysis, and clustering analysis were applied to establish the potential correlation between the phytochemical content and the antioxidant activities of the red grapes on the one hand, and grape variety, anatomical parts, and vineyard type (organic/conventional) on the other hand.

2.
Polymers (Basel) ; 15(6)2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36987138

RESUMEN

The food industry is a high consumer of polymer packing materials, sealing materials, and engineering components used in production equipment. Biobased polymer composites used in the food industry are obtained by incorporating different biogenic materials into the structure of a base polymer matrix. Renewable resources such as microalgae, bacteria, and plants may be used as biogenic materials for this purpose. Photoautotrophic microalgae are valuable microorganisms that are able to harvest sunlight energy and capture CO2 into biomass. They are characterized by their metabolic adaptability to environmental conditions, higher photosynthetic efficiency than terrestrial plants, and natural macromolecules and pigments. The flexibility of microalgae to grow in either low-nutrient or nutrient-rich environments (including wastewater) has led to the attention for their use in various biotechnological applications. Carbohydrates, proteins, and lipids are the main three classes of macromolecular compounds contained in microalgal biomass. The content in each of these components depends on their growth conditions. In general, proteins represent 40-70% of microalgae dry biomass, followed by carbohydrates (10-30%) and lipids (5-20%). A distinctive feature of microalgae cells is the presence of light-harvesting compounds such as photosynthetic pigments carotenoids, chlorophylls, and phycobilins, which are also receiving growing interest for applications in various industrial fields. The study comparatively reports on polymer composites obtained with biomass made of two species of green microalgae: Chlorella vulgaris and filamentous, gram-negative cyanobacterium Arthrospira. Experiments were conducted to reach an incorporation ratio of the biogenic material into the matrix in the 5-30% range, and the resulting materials were characterized by their mechanical and physicochemical properties.

3.
Artículo en Inglés | MEDLINE | ID: mdl-36673692

RESUMEN

Chemical analysis was performed on sediment core samples collected from three salt lakes, Amara Lake, Caineni Lake, and Movila Miresii Lake, located in the northeast of the Romanian Plain. The concentration of 10 main elements, 6 heavy metals (HMs), 8 rare earth elements (REEs), and 10 trace elements (TEs)-determined using neutron activation analysis (NAA)-showed variability dependent on the depth sections, lake genesis and geochemical characteristics (oxbow, fluvial harbor/liman and loess saucer type). The assessment of pollution indices (contamination factor, pollution load index, geoaccumulation index, and enrichment factor) highlighted low and moderate degrees of contamination for most of the investigated elements. Principal component analysis (PCA) extracted three principal components, explaining 70.33% (Amara Lake), 79.92% (Caineni Lake), and 71.42% (Movila Miresii Lake) of the observed variability. The principal components extracted were assigned to pedological contribution (37.42%-Amara Lake, 55.88%-Caineni Lake, and 15.31%-Movila Miresii Lake), salts depositions (due to the lack of a constant supply of freshwater and through evaporation during dry periods), atmospheric deposition (19.19%-Amara Lake, 13.80%-Caineni Lake, and 10.80%-Movila Miresii Lake), leaching from soil surface/denudation, rock weathering, and mixed anthropogenic input (e.g., agricultural runoff, wastewater discharges) (13.72%-Amara Lake, 10.24%-Caineni Lake, and 45.31%-Movila Miresii Lake).


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Lagos , Monitoreo del Ambiente , Rumanía , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos/análisis , Metales Pesados/análisis , China , Medición de Riesgo
4.
Artículo en Inglés | MEDLINE | ID: mdl-36429587

RESUMEN

This study is the third in a series of investigations conducted by the authors, and certainly the most comprehensive research regarding the former uranium, copper, and charcoal mines from a particular geographical area of Romania. In this respect, the present scientific incursion focused on two areas containing former extraction uranium ore sites, Ciudanovita and Lisava, as well as copper ore from Moldova Noua and charcoal mines from Anina, Banat Region, Romania. It highlighted that, for the first time, the heavy metal concentration was correlated with the values of physicochemical indicators of water (i.e., EC, DO, pH, resistivity, salinity, and ORP), by using multivariate analysis, to shape a regional based model on spatial distributions and the variability of toxic contaminants from the hydrographic basin of Banat, Romania, as a consequence of former uranium, copper, and charcoal mines. In this regard, 11 metals including Al, Cr, Mn, Fe, Ni, Co, Cu, Zn, Sr, Cd, and Pb from different water samples (well, spring, river, and lake), collected from three mining areas (uranium, copper, and coal mines) were investigated. Non-carcinogenic and carcinogenic health risks of seven heavy metals were assessed using the EDI, DIM, and THQ. The obtained THQ values were within the acceptable limits for cancer risks for adults, but as regards children, eight samples out of 18 proved toxic. However, the HRI and THQ average values for Cd (0.265 adults/0.996 children) and Pb (0.025 adults/0.095 children) for children were 3-4 times higher than those for adults. This is a source of concern as their prevalence in well water exposes children and residents in the Banat Region to the risk of various types of cancers.


Asunto(s)
Ríos , Uranio , Adulto , Niño , Humanos , Calidad del Agua , Lagos , Cobre , Carbón Orgánico , Cadmio , Plomo , Monitoreo del Ambiente/métodos , Medición de Riesgo
5.
Artículo en Inglés | MEDLINE | ID: mdl-36078359

RESUMEN

Groundwater, which is the main source of water for human consumption in many rural areas, has its quality determined by the complex interaction of environmental factors and anthropogenic activities. The present study evaluated the quality of shallow groundwater (1 to 25 m depth) in the rural area of the Târgoviste Plain, a densely populated area (200 inhabitants/km2) using 80 water samples collected from public wells. In order to explain the spatial distribution of the concentrations of the 19 physicochemical parameters considered (including heavy metals), the evaluation of groundwater quality for human consumption and potential impact on human health was conducted using the Water Quality Index (WQI), Integrated Weight Water Quality Index (IwWQI), Total Hazard Index (THI), and cumulative carcinogenic risk (CCR). For the WQI/IwWQI the comparative analysis of the two indices showed that for the WQI, it is important to select an optimal set of parameters, because use of a large number of physicochemical parameters can eclipse the values that exceed WHO guideline limits. In contrast, the use of entropy in the calculation of the IwWQI did not lead to eclipsing of exceedance, no matter the number of parameters used. Areas with poor and very poor groundwater quality according to the WQI/IwWQI overlapped, with a moderate risk to human health (THI > 1) for noncarcinogenic contaminants and also a risk of developing cancer according to the CCR average value (1.15 × 10-2). The health of 43% of the rural population in the Târgoviste Plain can be affected if they drink contaminated groundwater, and it is estimated that about 600 people can develop cancer during their lifetime. If the risk of developing cancer is reduced only in the rural population that does not have access to a water source from a centralized and verified network, the results suggest that 385 people (1.15%) can develop cancer as a result of consuming groundwater contaminated with heavy metals based on the average value of CCR. This value is lower than the general mortality rate in areas with high CCR and below the average number of cancer patients in Romania (2.65%). The quality of groundwater and the risk of developing diseases and cancer due to water consumption is directly proportional to the intensity of agricultural land use and inversely proportional to the depth of the groundwater layer, the distance from the main hydrographic network and the reservoirs, and the distance from the main city, Târgoviste. The complex and integrated analysis of groundwater quality using quality indices and indicators of health risk for the population, validated by hot-spot analysis and compared to the mortality rate, is an approach with practical applicability. This integrated approach allows public authorities, policymakers, and health services to implement an efficient monitoring program and optimize anthropogenic activities in order to prevent groundwater contamination and finally improve the quality of life for the residents in the area of this study.


Asunto(s)
Agua Potable , Agua Subterránea , Metales Pesados , Contaminantes Químicos del Agua , Agua Potable/análisis , Monitoreo del Ambiente/métodos , Agua Subterránea/análisis , Humanos , Metales Pesados/análisis , Calidad de Vida , Medición de Riesgo/métodos , Contaminantes Químicos del Agua/análisis , Calidad del Agua
6.
Foods ; 10(8)2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34441634

RESUMEN

Food plants provide a regulated source of delivery of functional compounds, plant secondary metabolites production being also tissue specific. In grape berries, the phenolic compounds, flavonoids and non-flavonoids, are distributed in the different parts of the fruit. The aim of this study was to investigate the applicability of FTIR and Raman screening spectroscopic techniques combined with multivariate statistical tools to find patterns in red grape berry parts (skin, seeds and pulp) according to grape variety and vineyard type (organic and conventional). Spectral data were acquired and processed using the same pattern for each different berry part (skin, seeds and pulp). Multivariate analysis has allowed a separation between extracts obtained from organic and conventional vineyards for each grape variety for all grape berry parts. The innovative approach presented in this work is low-cost and feasible, being expected to have applications in studies referring to the authenticity and traceability of foods. The findings of this study are useful as well in solving a great challenge that producers are confronting, namely the consumers' distrust of the organic origin of food products. Further analyses of the chemical composition of red grapes may enhance the capability of the method of using both vibrational spectroscopy and chemometrics for discriminating the hydroalcoholic extracts according to grape varieties.

7.
Materials (Basel) ; 14(11)2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34063918

RESUMEN

This paper presents the relative humidity (RH) sensing response of a resistive sensor employing sensing layers based on a ternary nanocomposite comprising graphene oxide-oxidized carbon nanohorns-polyvinylpyrrolidone (GO-CNHox-PVP), at 1/1/1, 1/2/1, and 1/3/1 w/w/w mass ratios. The sensing structure is composed of a silicon substrate, a SiO2 layer, and interdigitated transducers (IDT) electrodes, on which the sensing layer is deposited via the drop-casting method. The morphology and the composition of the sensing layers are investigated through scanning electron microscopy (SEM) and RAMAN spectroscopy. The RH sensing capability of each carbonaceous nanocomposite-based thin film was analyzed by applying a current between the two electrodes and by measuring the voltage difference when varying the RH from 0% to 100% in humid nitrogen. The sensors have a room temperature response comparable to that of a commercial humidity sensor and are characterized by a rapid response, excellent linearity, good sensitivity, and recovery time. The manufactured sensing devices' transfer functions were established, and we extracted the response and recovery times. While the structures with GO/CNHox/PVP at 1/1/1 ratio (w/w/w) had the best performance in terms of relative sensibility, response time, and recovery time, the sensors employing the GO/CNHox/PVP nanocomposite at the 1/2/1 ratio (w/w/w) had the best linearity. Moreover, the ternary mixture proved to have much better sensing properties compared to CNHox and CNHox-PVP-based sensing layers in terms of sensitivity and linearity. Each component of the ternary nanocomposites' functional role is explained based on their physical and chemical properties. We analyzed the potential mechanism associated with the sensors' response; among these, the effect of the p-type semiconductor behavior of CNHox and GO, correlated with swelling of the PVP, was dominant and led to increased resistance of the sensing layer.

8.
Plants (Basel) ; 9(11)2020 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-33143382

RESUMEN

The therapeutic benefits of extracts obtained from different red grape fractions were thoroughly studied, however, data regarding the comparison of phytochemical extracts prepared from the same varieties coming from organic versus conventional management systems are rather lacking. The present study aimed at comparing some of the phytochemical characteristics and antimicrobial activity of hydroalcoholic (50% v/v) extracts obtained from four varieties of red grapes cultivated respectively in organic and conventional vineyards. Total flavonoid content, total phenolic compounds, and antioxidant activity were determined by molecular absorption spectroscopy. Antimicrobial activity of the studied extracts was evaluated against common bacterial strains isolated from different habitats according to specific lab procedures. The analyses were performed in solid broths by applying the disk diffusion method, which allowed for the simultaneous determination of the spectrum of the sensitivity of the tested bacteria as well as the values of the minimum inhibition concentration (MIC). It was found that favorable antagonistic activities against the tested bacteria strains were exhibited by the hydroalcoholic extracts from the seeds of the organic varieties, respectively the skin of the conventional varieties.

9.
Molecules ; 25(14)2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32708236

RESUMEN

Starting from isoniazid and carboxylic acids as precursors, thirteen new hydrazides and 1,3,4-oxadiazoles of 2-(4-substituted-phenoxymethyl)-benzoic acids were synthesized and characterized by appropriate means. Their biological properties were evaluated in terms of apoptosis, cell cycle blocking, and drug metabolism gene expression on HCT-8 and HT-29 cell lines. In vitro antimicrobial tests were performed by the microplate Alamar Blue assay for the anti-mycobacterial activities and an adapted agar disk diffusion technique for other non-tubercular bacterial strains. The best antibacterial activity (anti-Mycobacterium tuberculosis effects) was proved by 9. Compounds 7, 8, and 9 determined blocking of G1 phase. Compound 7 proved to be toxic, inducing apoptosis in 54% of cells after 72 h, an effect that can be predicted by the increased expression of mRNA caspases 3 and 7 after 24 h. The influence of compounds on gene expression of enzymes implicated in drug metabolism indicates that synthesized compounds could be metabolized via other pathways than NAT2, spanning adverse effects of isoniazid. Compound 9 had the best antibacterial activity, being used as a disinfectant agent. Compounds 7, 8, and 9, seemed to have antitumor potential. Further studies on the action mechanism of these compounds on the cell cycle may bring new information regarding their biological activity.


Asunto(s)
Antiinfecciosos/química , Antineoplásicos/síntesis química , Antituberculosos/química , Hidrazinas/síntesis química , Oxadiazoles/síntesis química , Antiinfecciosos/farmacología , Antineoplásicos/farmacología , Antituberculosos/farmacología , Arilamina N-Acetiltransferasa/metabolismo , Benzoatos/química , Ácidos Carboxílicos/química , Evaluación Preclínica de Medicamentos , Fase G1/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Hidrazinas/farmacología , Isoniazida/química , Isoniazida/farmacología , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/efectos de los fármacos , Oxadiazoles/química , Oxadiazoles/farmacología , ARN Mensajero/efectos de los fármacos
10.
Bioelectrochemistry ; 129: 124-134, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31158797

RESUMEN

The antioxidant properties of different plant extracts are usually claimed and used by food, medicine and cosmetic industry due to their health promoting capacities. In this study the presence of antioxidant compounds and the total antioxidant capacity of water-soluble extracts, prepared using two extraction methods and a variety of solvents, have been determined and a rapid screening method has been developed. Plant extracts characterisation, composition and antioxidant properties were confirmed by FTIR and Raman spectroscopies. Voltammetry, amperometry and electrochemical impedance were used to highlight the total antioxidant capacity of each extract using an electrochemical gold nanozyme-sensor based on the enzyme-like catalytic activity of gold nanoparticles. Both anodic area of cyclic voltammograms (10.31 µA V) and electrochemical index (153) calculated using differential potential voltammetry show the total content of antioxidant compounds, allowing to discriminate between different extracts. Amperometric total antioxidant capacity measurements were associated with those from classical chemiluminescence and good correlation has been found (Pearson's correlation coefficient of 0.958).


Asunto(s)
Antioxidantes/química , Técnicas Electroquímicas/métodos , Oro/química , Hippophae/química , Lavandula/química , Nanopartículas del Metal/química , Extractos Vegetales/química , Antioxidantes/farmacología , Técnicas Biosensibles/métodos , Espectroscopía Dieléctrica , Peróxido de Hidrógeno/química , Extractos Vegetales/farmacología , Espectroscopía Infrarroja por Transformada de Fourier
11.
Bull Environ Contam Toxicol ; 102(4): 504-510, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30759262

RESUMEN

This study aims to investigate the dose rate and pollution level of Ciudanovita, Lisava, Anina, and Moldova Noua mining tailing dumps. In order to accomplish this, soil samples were collected according to LUCAS 2009/2012, in the summer of 2017. To start with, these samples were measured in situ for dose rate and revealed some interesting aspects, following this, they were investigated in the laboratory using different physico-chemical methods for more complex data. Therefore, two techniques have been used for structural investigation that revealed some particularities in terms of morphology, color and shape (optical microscopy, scanning electron microscopy) and, two for chemical composition (Fourier transform infrared spectroscopy and inductive coupled plasma mass spectrometry), which provided the qualitative confirmation of chemical groups involved in soil composition along with the heavy and radioactive metals presence (i.e. Pb, U, Cu, Cr, Cd, Ni, Zn, and Mn), expressed also by contamination factor.


Asunto(s)
Cobre/análisis , Monitoreo del Ambiente/métodos , Minería , Contaminantes del Suelo/análisis , Uranio/análisis , Moldavia , Monitoreo de Radiación/métodos , Medición de Riesgo , Suelo/química
12.
Environ Sci Pollut Res Int ; 23(15): 15395-406, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27115705

RESUMEN

The aim of this study was to link the concentrations of particulate matter with an aerodynamic diameter below 2.5 µm (PM2.5) and associated heavy metals with occurrence of wheezing and hospitalizations due to wheezing in 111 children who live near metallurgical plants in Targoviste City, Romania. A group of 72 children with high levels of immunoglobulin E (IgE) and eosinophils, as well as frequent wheezing episodes, was geolocated on digital thematic maps. Monitoring campaigns and medical assessments were performed over two consecutive years (2013-2014). The multiannual average concentrations of PM2.5 ranged from 4.6 to 22.5 µg m(-3), up to a maximum value of 102 µg m(-3). Significant correlations (p < 0.01) were observed between the locations of the children with respiratory issues and the PM2.5 multiannual average (r = 0.985) and PM2.5 maximum (r = 0.813). Fe, Ni, Cd, and Cr were the main marker elements of the emissions from steel production and metal-working facilities in the Targoviste area. The results support the hypothesis that increased PM2.5 levels directly influence wheezing symptom and asthma attacks in the analyzed group. IgE, eosinophils, and wheezing episodes may be considered key indicators with which to evaluate the adverse effects of PM2.5 air pollution on children's health.


Asunto(s)
Contaminantes Atmosféricos/análisis , Asma/epidemiología , Monitoreo del Ambiente/métodos , Metalurgia , Metales Pesados/análisis , Material Particulado/análisis , Asma/inducido químicamente , Niño , Humanos , Tamaño de la Partícula , Ruidos Respiratorios/efectos de los fármacos , Rumanía
13.
Bull Environ Contam Toxicol ; 89(3): 580-6, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22760846

RESUMEN

Our study was dedicated to the analysis of air pollution level with metals in Dambovita County, Romania; maps of the concentration distributions for air pollutants were drawn; statistical analysis includes calculation of the background concentrations and the contamination factors. The highest values of the contamination factor CF is 63.1 ± 6.63 for mosses samples and 33.12 ± 3.96 for lichens and it indicates extreme contaminations in the surroundings of steel works and an electric plant. The comparison of the distribution maps for Cr, Cu, Fe, Ni, Pb and Zn concentrations enables the identification of the pollution sources, the limits of areas with very high levels of pollution, the comparison of the concentration gradients in some areas and the influence of woodlands on the spread of pollutants through the air.


Asunto(s)
Contaminantes Atmosféricos/análisis , Briófitas/química , Monitoreo del Ambiente/métodos , Líquenes/química , Metales/análisis , Espectrometría por Rayos X/métodos , Espectrofotometría Atómica/métodos
14.
Bull Environ Contam Toxicol ; 84(5): 641-6, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20405104

RESUMEN

The aim of this work was to determine the heavy metal content of the fruiting bodies of four species of wild edible mushrooms and their respective substrates. The samples were collected from Dambovita County, Romania, at various distances from of a metal smelter, to asses the concentration of Cr, Mn, Fe, Ni, Cu, Zn, Se and Cd in the wild edible mushrooms and their substrate using Energy Dispersive X-ray Fluorescence (EDXRF) spectrometry together with Flame Atomic Absorption (FAAS) spectrometry. A quantitative evaluation of the relationship of element uptake by mushrooms from substrate was made by calculating the coefficient accumulation (K(a)). A high accumulation of Zn (K(a) range 1.01 to 2.01) was observed in mushrooms growing in the vicinity of the metal smelter.


Asunto(s)
Agaricales/metabolismo , Contaminación de Alimentos/análisis , Metalurgia , Metales Pesados/metabolismo , Biotransformación , Monitoreo del Ambiente , Cuerpos Fructíferos de los Hongos/química , Cuerpos Fructíferos de los Hongos/metabolismo , Metales Pesados/análisis , Espectrometría por Rayos X , Espectrofotometría Atómica , Zinc/análisis , Zinc/metabolismo
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