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1.
Biotechnol Lett ; 45(9): 1133-1145, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37395870

RESUMEN

Metabolic engineering has shown that optimizing metabolic pathways' fluxes for industrial purposes requires a methodical approach. Accordingly, in this study, in silico metabolic modeling was utilized to characterize the lesser-known strain Basfia succiniciproducens under different environmental conditions, followed by the use of industrially relevant substrates for succinic acid synthesis. Based on RT-qPCR carried out in flask experiments, we discovered a relatively large difference in the expression levels of ldhA gene compared to glucose in both xylose and glycerol cultures. In bioreactor-scale fermentations, the impact of different gas phases (CO2, CO2/AIR) on biomass yield, substrate consumption, and metabolite profiles was also investigated. In the case of glycerol, the addition of CO2 increased biomass as well as target product formation, while using CO2/AIR gas phase resulted in higher target product yield (0.184 mM⋅mM-1). In case of xylose, using CO2 alone would result in higher succinic acid production (0.277 mM⋅mM-1). The promising rumen bacteria, B. succiniciproducens, has shown to be suitable for succinic acid production from both xylose and glycerol. As a result, our findings present new opportunities for broadening the range of raw materials used in this significant biochemical process. Our study also sheds light on fermentation parameter optimization for this strain, namely that, CO2/AIR supply has a positive effect on target product formation.


Asunto(s)
Dióxido de Carbono , Ácido Succínico , Animales , Ácido Succínico/metabolismo , Glicerol , Xilosa , Fermentación
2.
Environ Monit Assess ; 195(7): 798, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37266820

RESUMEN

Modern societies are characterized by increased air pollution, and particulate matter (PM) is one of the most significant air pollutants and is a major environmental health problem. Therefore, long- and short-term exposure via inhalation, ingestion, and dermal absorption of particulate matter may cause series health issues, such as cardio pulmonary and lung cancer disease. Air pollutants accumulation is significantly higher in closed regions or basins characterized by strong thermal inversions, especially during the cold period such in case of the Ciuc basin. The aim of this study was to carry out the time series analysis of PM2.5, PM10 and TSP in the Ciuc basin for the period 2010-2019, in order to decipher the main characteristics of air pollution in this region.The data obtained were analyzed on a daily, monthly and annual basis by different statistical methods. The average monthly concentration of TSP (60.03 µg m-3), PM10 (19.21 µg m-3) and PM2.5 (14.73 µg m-3) particulate matter in the studied regions varied between 29.84-134.79 µg m-3, 4.38-63.51 µg m-3 and 4.01-54.41 µg m-3, respectively. Regarding the ratio of PM2.5 and PM10 in the total particulate matter (TPM) was 0.25 and 0.33. Due to meteorological factors and emission fluctuations, particulate matter exhibits high seasonal variations, therefore the highest concentrations were recorded during the cold period, while the lowest values were observed in summer. The percentage of PM10 exceedances (50 µg m-3) represents 24.8% in winter, meanwhile in autumn and spring a significantly lower exceedances percentage was observed, 2.6% and 1.7%, respectively. The correlation analysis revealed that the correlation level of the studied pollutants varied between 0.73-0.78.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Material Particulado/análisis , Microclima , Monitoreo del Ambiente/métodos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Estaciones del Año
3.
Environ Monit Assess ; 193(4): 176, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33751243

RESUMEN

In the present study, the concentrations of trace elements in PM10 were determined and analyzed at 115 monitoring stations in Romania throughout the period 2009-2018. The spatiotemporal distribution of trace element concentrations of PM10, the source apportionment and health impact assessment, was carried out. The results showed a very high multi-annual mean concentration for PM10 and trace elements as well. The multiannual average concentration of PM10 was higher by 29.75% than the World Health Organization recommendation. All studied air pollutants showed a decreasing trend during the studied years, showing with 17.84%, 50.21%, 43.36%, 11.27%, and 72.09% lower values for PM10, As-, Cd-, Ni-, and Pb-, respectively, due to environmental regulations. To assess the human health impact, the hazard quotient (HQ) and cancer risk (CR) were calculated using the health risk model developed by the US Environmental Protection Agency (EPA). The Cd and Ni might present a non-carcinogenic risk to both adults and children; however, the hazard quotient values are higher than the safe limit, with 9.53 and 1.93, respectively. In addition, our study results revealed that the inhalation of As, Cd and the dermal absorption of all studied trace elements were considered as the most important risk factors for developing cancer, especially in case of adults.


Asunto(s)
Contaminantes Atmosféricos , Metales Pesados , Oligoelementos , Adulto , Aerosoles , Contaminantes Atmosféricos/análisis , Cadmio , Niño , Monitoreo del Ambiente , Europa (Continente) , Evaluación del Impacto en la Salud , Humanos , Plomo , Metales Pesados/análisis , Medición de Riesgo , Rumanía , Oligoelementos/análisis
4.
Environ Res ; 188: 109872, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32846651

RESUMEN

A comprehensive analysis of the chemical composition of precipitation was performed on rainwater samples collected between 1978 and 2017 over the conterminous US. A total of 86470 data records downloaded from the National Atmospheric Deposition Program were statistically analyzed and assessed in terms of precipitation chemistry. The ion abundance followed the Cl⁻ > Na⁺ > SO42⁻ > Ca2⁺ > H⁺ > NH4⁺ > NO3⁻ > Mg2⁺ > HCO3⁻ > K⁺ downward trend, showing that chloride and sodium were the most dominant among anions and cations. Ca2+, SO42- and NH4+ concentrations were notable in desert areas or in regions with significant anthropogenic activity. Frequency analysis of pH values showed that the 87.90% of the pH is acidic, exhibiting values under 5.6. According to the acidifying and neutralization potential, rainwater pH is mostly alkaline in the Western region, presenting acidic values in highly industrialized areas, in the Central and Eastern Regions. Fractional acidity showed that in the majority of the studied sampling sites 61% of the acidity in precipitation is neutralized, due to the presence of the main neutralizing agents (NH4+, Ca2+, Na+), fact sustained by the neutralization factor values. The relationship between acidic and alkaline components was thoroughly examined by ionic ratios and the ammonium availability index. Wet deposition rates of major ions confirmed the dominance of acidic species over neutralizing ones, as well as the significant imprint of regional climate and heavily industrialized areas on the precipitation chemistry. The complex major ion source apportionment, including marine and crustal enrichment factors, sea salt and non-sea salt fractions, Spearman's rank correlation analysis and Principal Component Analysis, showed that anthropogenic influences are the most significant, including coal-fired power plants, oil refineries, major industries and agricultural activities. Crustal and marine sources also presented a prominent imprint on the rainwater chemistry of the conterminous US.


Asunto(s)
Contaminantes Atmosféricos , Lluvia , Contaminantes Atmosféricos/análisis , Aniones/análisis , Cationes , Cloruros , Monitoreo del Ambiente , Estaciones del Año , Estados Unidos
5.
Sci Rep ; 14(1): 881, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-38195806

RESUMEN

The physical-chemical characteristics of different types of flours are essential for understanding their composition, nutritional value, and functional properties as well. The aim of this research was to identify the variability of the different wheat flours available in Romania. In this study 39 different wheat flours were selected and the following parameters were analyzed in the laboratory: moisture content, ash content, gluten content (wet and dry) and wet gluten spreading. The tested flours were classified into four different classes according to their ash content: 480 (ash content 0.48%) (N = 11), 550 (0.55%) (N = 9), 650 (0.65%) (N = 8), 1100 (1.1%) (N = 11). Mathematical and statistical methods were used to analyze the obtained results: descriptive statistics, box-plot, Spearman correlation and hierarchical cluster analysis. The results revealed that moisture content varied between 9.5 and 11.8%. In terms of ash content, the lowest and highest measured values were 0.427-2.04 g/100 g. The average wet gluten content of the studied flours varied between 30 and 32%, while the average dry gluten content was 12.8%. The findings indicate that the moisture content of all examined flour samples was within permissible levels for extended storage, aligning with established standards. Gluten is a key and essential parameter for bread making because influences the dough mixing and baking properties. The mineral content, represented by ash content, is influenced by cereal type and milling process, with wheat's ash content ranging between 1.5 and 2%. Flours with high wet gluten content (> 34%) can be used to improve the properties of lower quality flours. Further studies are necessary in order to determine the possible health effects of different cereal varieties.


Asunto(s)
Harina , Glútenes , Rumanía , Pan , Cromatografía de Gases , Grano Comestible
6.
Heliyon ; 10(11): e31513, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38841466

RESUMEN

The aim of this study was to provide customers with additional information by analyzing and comparing the nutritional data of different dairy product varieties in Romania. Milk is an ideal source of nutrition because it contains a balanced combination of carbohydrates, proteins, fats, minerals, and vitamins. In this study, the nutritional constituents of dairy products from Romania were examined. In total, the nutritional characteristics of 143 dairy products: milk (N-42), sour cream (N-37), cheese (N-40) and butter (N-24) (energetic value, fat content, fat of which saturated fatty acids, carbohydrates, sugar, proteins, salt, calcium) were collected from the market and statistically analyzed. The average energy values of the studied dairy products were 188/261 kJ/100 ml for milk, 610/739/1091 kJ/100 g for sour cream, 2359/3022 kJ/100 g for butter and 1306 kJ/100 g for cheese. The fat concentration of the studied products was standardized. Based on the cluster analysis, some products whose characteristics differed significantly included Gordon milk (1.5%, 3.5%), Keresztúri and Szépvízi cheese.

7.
Heliyon ; 9(11): e21810, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38027749

RESUMEN

To detect the spatial differences of atmospheric pollutants in urban and suburban areas is important for observing their aspects on regional air quality, climate, and human health. This study is focused on the evolution of PM2.5, PM10, NOx and SO2, concentrations, and meteorological parameters from 2010 to 2022, at urban and suburban area in the two Romanian city: Brasov and Iasi. The daily patterns of most pollutants in urban and suburban areas, are strongly linked to land-traffic emissions. The seasonal differences were observation of the studied air pollutants displays visible decreasing in warm period and increased concentrations in cold period. Significant higher (25%- Brasov, 28%- Iasi) PM10 were found in urban area concentration probably caused by enhanced vehicular emissions over these areas induced by urban planning and mobility policies. The average relative risk caused by PM10 for all-cause mortality in the urban region was 1.021 (±0.004) in Brasov, and significantly higher in Iasi 1.030 (±0.005). In suburban regions this risk was lower with 33 % 1.014 (±0.006) in Brasov and 30 % 1.021 (±0.003) in Iasi. The main objective of this research was to identify the difference of air pollutants and meteorological parameters in the urban and suburban region of the studied city.

8.
Sci Rep ; 12(1): 11817, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35821520

RESUMEN

Refineries and petrochemical industries are known to be the principal sources of emissions for a number of air pollutants, such as Volatile Organic Compounds (VOCs), greenhouse gases and particulate matter, which negatively affect the air quality. The primary goal of this research was the time series analysis of PM2.5, PM10, As, Cd, Ni, Pb, benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, CO, NO, NO2, NOx, SO2 and O3 over an eleven-year period (2009-2019) and the connection between air pollution and meteorological parameters (air temperature, precipitation quantity and relative humidity). Regarding the pollution level of the major pollutants, the minimum pollution levels, except SO2 and O3, were recorded during warmer periods, meanwhile increased levels, were detected during the cold period (in winter). The air pollutants' concentration and distribution are affected by meteorological parameters, such as wind speed and direction, rainfall or even relative humidity. Therefore, the highest concentrations in the winter season were 1.25 times higher than in autumn, 1.3 times higher than the average annual value, 1.57 times higher than in spring and 1.79 times higher than in summer. Monthly variation of O3 showed lower concentration during winter (27.62 µg/m3) and higher in summer (46.42 µg/m3). Based on the statistical analysis, a significant Spearman correlation was detected between the studied air pollutants and meteorological parameters, and according to the Principal Component Analysis (PCA) and cluster analysis, some common sources were also detected.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente , Rumanía , Factores de Tiempo
9.
Toxicol Rep ; 9: 556-562, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35386513

RESUMEN

Air pollution, especially the concentration of particulate matter (PM2.5, PM10) is a major issue and is the biggest environmental risk for early death. In the present study, we aimed to estimate the human health risk and to describe the spatial and temporal variation of particulate matter in Romania between 2009 and 2018. The average concentration of PM2.5 and PM10 particulate matter in the eight studied regions varied between 17.01 and 22.91 µg m-3 and 23.02-33.29 µg m-3, while the PM2.5/PM10 ratio varied between 0.52 and 0.76, respectively. The relative risk generated by PM10 in all-cause mortality had a significant variation between the regions, a relative risk of 1.017 in case of Bucharest and1.025 for western regions, with an average of 1.020 ( ± 0.002). According to our observations, a positive relative risk was identified in the case of cardiopulmonary and lung cancer morbidity mainly attributed to PM2.5 exposure, hence the resulted risk for the country average values was 1.26 ( ± 0.023) and 1.42 ( ± 0.037), respectively. The results revealed that the excess risk and attributable fraction for cardiopulmonary mortality can be reduced by 26.7% and 21.0%. Analyzing the evolution of particulate matters and the possible health impacts of PM2.5 and PM10 in all region of Romania a strong positive correlation was observed. Since the distributions of PM in different region had significant variation, more investigation is required to understand and decipher the most important regional emission sources for each region. In order to address this issue an in-depth investigation should separately analyze the regional characteristics of air pollution.

10.
Sci Rep ; 11(1): 7049, 2021 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-33782481

RESUMEN

The present study aims to analyze the temporal variations of PM10 and to assess the health risk indexes caused by trace elements from particulate matter (PM10) via inhalation, ingestion, and dermal absorption by adults and children in Copșa Mica (Romania) during 2009-2019. The results revealed a high multi-annual mean concentration of PM10 and trace elements. The analyzed air pollutants showed a decreasing trend during the studied years, therefore 44.11%, 43.48%, 36.07%, 16.02%, and 15.80% lower values were observed for As, Cd, Ni, PM10, and Pb, respectively, due to environmental regulations. The daily exceedance percentage of Pb and Cd was very high, representing 21.74% and 11.26%, followed by PM10 and As concentrations with 4.72% and 3.92%. The ratio between the trace element concentration measured in Copșa Mica and the country average was 2.46, 4.01, 2.44 and 10.52 times higher for As, Cd, Ni and Pb. The calculated Hazard Quotient values via inhalation were higher than the safe limit (1), which accounted 1.81, 3.89 and 4.52, for As, Cd and Ni, respectively, indicating that the trace elements might present a non-carcinogenic risk to both adults and children. Furthermore, the concentration of all studied trace elements in Copșa Mica showed cancer risk for adults via inhalation and dermal absorption as well.


Asunto(s)
Evaluación del Impacto en la Salud , Material Particulado/análisis , Oligoelementos/análisis , Adulto , Niño , Humanos , Material Particulado/toxicidad , Rumanía , Oligoelementos/toxicidad , Tiempo (Meteorología)
11.
Environ Sci Pollut Res Int ; 27(30): 38181-38199, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32617823

RESUMEN

The air quality decrease, especially in urban areas, is related to local-scale conditions and to dispersion of air pollutants (regional and long-range) as well. The main objective of this study was to decipher the seasonal variation of PM10, NO, NO2, NOx, SO2, O3, and CO over a 1-year period (2017) and the possible relationships between air pollution and meteorological variables. Furthermore, trajectory cluster analysis and concentration-weighted trajectory (CWT) methods were used to assess the trajectories and the source-receptor relationship of PM10 in the Ciuc basin Transylvania, known as the "Cold Pole" of Romania. The pollutants show lower concentrations during warmer periods, especially during summer, and significantly higher concentrations were observed on heating season in winter due to seasonal variations in energy use (biomass burning) and atmospheric stability. Subsequently, in February, the highest concentration of PM10 was 132 µg/m3, which is 4 times higher than the highest recorded monthly mean. Our results indicate a negative correlation between CO/temperature (- 0.89), NOx/temperature (- 0.84) and positive between NOx/PM10 (0.95), CO/PM10 (0.9), and NOx/CO (0.98), respectively. Dominant transport pathways were identified and the results revealed that slow-moving southerly (~ 45%) and northwesterly (~ 32%) air masses represent almost 80% and mainly regional flows were discerned. During 2017, increased PM10 levels were measured at the study site when air masses arrived mostly from northwest and southeast. The CWT and polarplot models show a strong seasonal variation and significant differences were observed between weekdays and weekends, namely highest PM10 concentrations during weekends at low wind speed (2-4 m/s).


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Rumanía , Estaciones del Año
12.
Environ Sci Pollut Res Int ; 27(9): 9382-9402, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31916162

RESUMEN

The aim of this study is the assessment of rainwater composition, regarding the various sources of major ions and heavy metals, taking into account the characteristic atmospheric circulations and the main air mass transport routes. Rainwater samples were analyzed for pH, electrical conductivity, major ions, and heavy metals. At all sampling sites, the most abundant anions were SO42- and Cl-, while the dominant cations were Ca2+ and Mg2+. Regarding heavy metals, the dominance of Pb and Cd was found. The contribution of soil dust from the mining activities and the dissolution of CaCO3, MgCO3, and CaSO4·2H2O in the rainwater explains the high concentrations of Ca2+, Mg2+, and SO42-. The overall precipitation contamination with heavy metals at the three sampling sites was assessed by the degree of contamination, showing that Pb and Cd presents the highest risks of all heavy metals. The values of toxicity potential suggested an elevated risk for human health in case of rainwater ingestion, especially in rural areas. Spearman correlation and PCA indicated that the chemical characteristic of the rainwater is primarily controlled by sources such as agricultural activities, mixed and crustal sources, traffic, and other anthropogenic, industrial influences, mining activities, smelting operations, coal combustion, and metal production.


Asunto(s)
Metales Pesados/análisis , Contaminantes del Suelo/análisis , China , Monitoreo del Ambiente , Contaminación Ambiental/análisis , Humanos , Minería , Medición de Riesgo , Rumanía
13.
Sci Total Environ ; 647: 275-289, 2019 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-30081365

RESUMEN

A comprehensive study on the chemical composition of precipitation, the influence of peat fires and their relations with atmospheric circulation was conducted in the year of 2012, in two intra-mountain basins, the Ciuc basin (CB) and the Giurgeu basin (GB), Eastern Carpathians, Romania. Atmospheric circulation types showed the presence of a westerly anticyclonic circulation, characterized by a strong development of the Azores High to the northern Atlantic, contributing to the appearance of peat-fires. Using ROCADA daily gridded climatic datasets, the maximum and minimum daily temperatures were extracted, showing deviation from 2 °C to 6 °C in the studied year against the multiannual mean for the 1981-2016 period. Rainwater samples were analyzed for pH, major anions and cations; HCO3- concentrations were calculated based on the empirical relationship between pH and HCO3-. The results showed that 45.16% and 54.55% of precipitation had pH > 7.0 at CB and GB, respectively. NH3, NH4+ and Ca2+ are the main neutralizing agents. The significant correlation between SO42- and NH4+ (r = 0.711 - CB; r = 0.736 - GB) indicated neutralization by NH3 in the forms of (NH4)2SO4 and NH4HSO4. Positive regression coefficient between the sum of (H+ + [NH4+] + [Ca2+]) and the sum of ([nss - SO42-] + [NO3-]) (r = 0.855 - CB; r = 0.796 - GB), showed that acid neutralization was primarily brought by NH4+ and/or CaCO3. Using Na as an indicator of marine origin, the proportions of sea salt and non-sea-salt were estimated from elemental ratios. According to correlation analysis and PCA, main acidic ions (SO42- and NO3-) and NH4+ were mainly derived from anthropogenic activities (biomass burning, peat fires, fertilization), while Ca2+ and Mg2+ originated from terrestrial sources. The behavior of gaseous pollutants and smoke distribution resulted from peat fires were deciphered using the HYSPLIT model in a case study.

15.
J Biomol Struct Dyn ; 35(9): 1874-1889, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27492654

RESUMEN

Recently, several approaches have been published in order to develop a functional biosynthesis route for the non-natural compound 1,4-butanediol (BDO) in E. coli using glucose as a sole carbon source or starting from xylose. Among these studies, there was reported as high as 18 g/L product concentration achieved by industrial strains, however BDO production varies greatly in case of the reviewed studies. Our motivation was to build a simple heterologous pathway for this compound in E. coli and to design an appropriate cellular chassis based on a systemic biology approach, using constraint-based flux balance analysis and bi-level optimization for gene knock-out prediction. Thus, the present study reports, at the "proof-of concept" level, our findings related to model-driven development of a metabolically engineered E. coli strain lacking key genes for ethanol, lactate and formate production (ΔpflB, ΔldhA and ΔadhE), with a three-step biosynthetic pathway. We found this strain to produce a limited quantity of 1,4-BDO (.89 mg/L BDO under microaerobic conditions and .82 mg/L under anaerobic conditions). Using glycerol as carbon source, an approach, which to our knowledge has not been tackled before, our results suggest that further metabolic optimization is needed (gene-introductions or knock-outs, promoter fine-tuning) to address the redox potential imbalance problem and to achieve development of an industrially sustainable strain. Our experimental data on culture conditions, growth dynamics and fermentation parameters can consist a base for ongoing research on gene expression profiles and genetic stability of such metabolically engineered E. coli strains.


Asunto(s)
Bacterias Aerobias/metabolismo , Butileno Glicoles/metabolismo , Escherichia coli/genética , Ingeniería Metabólica , Bacterias Aerobias/química , Bacterias Aerobias/genética , Vías Biosintéticas/genética , Butileno Glicoles/química , Simulación por Computador , Escherichia coli/química , Fermentación , Técnicas de Inactivación de Genes , Glucosa/química , Glucosa/metabolismo , Glicerol/química , Xilosa/química , Xilosa/genética
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