Bioaccumulation Processes Research Articles

Study of organic pollution in superficial sediments of Meliane river catchment area: aliphatic and polycyclic aromatic hydrocarbons.

Organic contaminants can be accumulated in aquatic systems even at trace concentrations with potential threats to the environment and human health. The present study has been performed to evaluate the effects of organochlorines and polyaromatic hydrocarbons on surface sediments of the Meliane river catchment. Their determination provides an essential scientific approach for a better understanding of the expected sources and the processes of bioaccumulation. The concentrations of saturated hydrocarbons in extractable organic matter of the dry sediment were found ranging from 0.58 to 3 83μgkg-1 and PAHs content ranged from 63 to 131μgkg-1. These results indicated the adherence of Oued Meliane to the pollution of the Tunis Gulf. The fraction of saturated hydrocarbons extracted from the sediments of Oued Meliane included a majority of organic compounds of biogenic nature with a small oil input. In addition, characterization with the TAR index and the LMW/HMW index confirmed that terrigenous inputs in this fraction are more abundant than aquatic inputs. The characterization of PAHs fraction has shown its pyrolitic origin with a predominance of high molecular weight PAHs.

Metal accumulation by plants growing in China: Capacity, synergy, and moderator effects

Plant accumulation of heavy metals (HMs) has become a global concern, however, the bio-accumulation distributions, their inter-correlations, and relationships with influencing factors remain unknown at the national scale in China. Here, we investigate the bio-accumulation capacity, as indicated as bio-concentration factors (BCFs), for chromium (Cr), cadmium (Cd), lead (Pb), copper (Cu), and Zinc (Zn) across plants growing on China (span 22 provinces) and their relationships, based on national meta-analysis of 46 publications (210 species, and 66 families). Results showed that: (1) Plants show diverse capacity of HM accumulation. About 20.6% of the plant tissue cases indicates strong phytoremediation ability for HMs (i.e., Ln BCF > 0), including 38.5% of Cd, 28.5% of Cr, 11.9% of Cu, 7.6% of Pb, and 16.6% of Zn. The families with the greatest numbers of published strong HMs phytoremediation cases are Poaceae, Asteraceae, and Brassicaceae. (2) The capacity to uptake and accumulation one of these HMs is significantly correlated with the ability to absorb the others (p < .001) for both all plants and organs but differ in strength and degree of correlations. The synergistic effect of the accumulation of these metals is more stable in stems than other parts. Leaves and roots differ significantly in metal co-accumulating strengths and enrichment patterns. (3) Experimental factors affect the HM bio-accumulation processes and bio-mediated mechanisms and responsible for substantial heterogeneous in phytoremediation effectiveness. These findings suggest that the use of plant as a soil pollution indicator and phytoremediation technique, synergistic strategies of bio-accumulation as ecological indicators and bio-mediated mechanisms for phytoremediation of polymetallic contaminated areas, with considering sensitivity of influencing factors, might have a crucial effect on the eco-service, eco-environment, and land management and could reduce material hazards by increasing bio-accumulation efficiency, or could reduce human health risk by decreasing potential intake of HMs. We argue that this meta-analysis would aid the assessment of the strength of general HM risks, the evaluation of regional soil contamination hazards and consequences, and the configuration of plant species and traits efficiently for phytoremediation potential.

Influence of Pulsed Electric Field on Accumulation of Calcium in Lactobacillus rhamnosus B 442.

Calcium is an element that performs many important functions in the human body. A study was conducted on the use of a pulsed electric field (PEF) to enrich cells of Lactobacillus rhamnosus B 442 in calcium ions. The highest concentration of calcium ions in bacterial cells (7.30 mg/g d.m.) was obtained at ion concentration of 200 µg/ml of medium and with the use of the following PEF parameters: field strength 3.0 kV/cm, exposure time 10 min, pulse width 75 ms and 20 h of culturing after which bacteria were treated with the field. Cell biomass varied in the range from 0.09 g/g d.m. to 0.252 g/g d.m., and the total number of bacteria ranged from 1010 CFU/ml to 1012 CFU/ml. Microscope photographs prove that calcium ions were situated within the cells of the bacteria, and electroporation contributed to an increase in the effectiveness of the ion bioaccumulation process. Samples containing calcium and subjected to electroporation displayed intensive fluorescence. The significance of this research was the possibility of using probiotic bacteria enriched with calcium ions for the production of functional food in subsequent studies.

Sustainable microbial cell nanofactory for zinc oxide nanoparticles production by zinc-tolerant probiotic Lactobacillus plantarum strain TA4

BackgroundThe use of microorganisms in the biosynthesis of zinc oxide nanoparticles (ZnO NPs) has recently emerged as an alternative to chemical and physical methods due to its low-cost and eco-friendly method. Several lactic acid bacteria (LAB) have developed mechanisms in tolerating Zn2+ through prevention against their toxicity and the production of ZnO NPs. The LAB’s main resistance mechanism to Zn2+ is highly depended on the microorganisms’ ability to interact with Zn2+ either through biosorption or bioaccumulation processes. Besides the inadequate studies conducted on biosynthesis with the use of zinc-tolerant probiotics, the understanding regarding the mechanism involved in this process is not clear. Therefore, this study determines the features of probiotic LAB strain TA4 related to its resistance to Zn2+. It also attempts to illustrate its potential in creating a sustainable microbial cell nanofactory of ZnO NPs.ResultsA zinc-tolerant probiotic strain TA4, which was isolated from local fermented food, was selected based on the principal component analysis (PCA) with the highest score of probiotic attributes. Based on the 16S rRNA gene analysis, this strain was identified as Lactobacillus plantarum strain TA4, indicating its high resistance to Zn2+ at a maximum tolerable concentration (MTC) value of 500 mM and its capability of producing ZnO NPs. The UV–visible spectroscopy analysis proved the formations of ZnO NPs through the notable absorption peak at 380 nm. It was also found from the dynamic light scattering (DLS) analysis that the Z-average particle size amounted to 124.2 nm with monodisperse ZnO NPs. Studies on scanning electron microscope (SEM), energy-dispersive X-ray (EDX) spectroscopy, and Fourier-transform infrared spectroscopy (FT-IR) revealed that the main mechanisms in ZnO NPs biosynthesis were facilitated by the Zn2+ biosorption ability through the functional groups present on the cell surface of strain TA4.ConclusionsThe strong ability of zinc-tolerant probiotic of L. plantarum strain TA4 to tolerate high Zn2+ concentration and to produce ZnO NPs highlights the unique properties of these bacteria as a natural microbial cell nanofactory for a more sustainable and eco-friendly practice of ZnO NPs biosynthesis.

The trophic ecology of marine catfishes in south-eastern Brazil

AbstractThe stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) and total mercury concentrations (THg) of the three marine catfish speciesAspistor luniscutis,Bagre bagreandGenidens genidenswere evaluated to understand their trophic relationship in northern Rio de Janeiro state, south-eastern Brazil. The δ13C was similar among the three marine catfishes, whereas δ15N was similar inA. luniscutisandB. bagreand lower inG. genidens. THg was higher inG. genidensand lower inB. bagre. The greater assimilation of Sciaenidae fishes and squids byA. luniscutisandB. bagreresulted in smaller isotopic niche areas and trophic diversity but higher isotopic niche overlap, trophic redundancy and evenness. ForG. genidens, the similar assimilation of all prey items resulted in the broadest isotopic niche among the marine catfishes. The higher mercury content inG. genidensis consistent with an increased important contribution of prey with a higher Hg burden. The bioaccumulation process was indicated by significant correlations of δ15N and THg with total length and total mass. Additionally, a significant correlation between THg and δ15N reflected the biomagnification process through the food web.

Bioconcentration of Essential and Nonessential Elements in Black Sea Turbot (Psetta Maxima Maeotica Linnaeus, 1758) in Relation to Fish Gender

This study investigates the influence of gender in the bioconcentration of essential and nonessential elements in different parts of Black Sea turbot (Psetta maxima maeotica) body, from an area considered under high anthropogenic pressure (the Constanta City Black Sea Coastal Area in Romania). A number of 13 elements (Ca, Mg, Na, K, Fe, Zn, Mn, Cu, Ni, Cr, As, Pb and Cd) were measured in various sample types: muscle, stomach, stomach content, intestine, intestine content, gonads, liver, spleen, gills and caudal fin. Turbot adults (4–5 years old) were separated, according to their gender, into two groups (20 males, 20 females, respectively), and a high total number of samples (1200 from both groups) were prepared and analyzed, in triplicate, with Flame Atomic Absorption Spectrometry and High-Resolution Continuum Source Atomic Absorption Spectrometry with Graphite Furnace techniques. The results were statistically analyzed in order to emphasize the bioconcentration of the determined elements in different tissues of wild turbot males vs. females, and also to contribute to an upgraded characterization of the Romanian Black Sea Coast, around Constanta City, in terms of heavy metals pollution. The essential elements Mg and Zn have different roles in the gonads of males and females, as they were the only elements with completely different patterns between the analyzed groups of specimens. The concentrations of studied elements in muscle were not similar with the data provided by literature, suggesting that chemistry of the habitat and food plays a major role in the availability of the metals in the body of analyzed fish species. The gender influenced the bioaccumulation process of all analyzed elements in most tissues since turbot male specimens accumulated higher concentration of metals compared to females. The highest bioaccumulation capacity in terms of Ca, Mg, Na, Ni, As, Zn and Cd was registered in caudal fin, liver and intestine tissues. Also, other elements such as K, Fe, Cu and Mn had the highest bioaccumulation in their muscle, spleen, liver and gills tissues. The concentrations of toxic metals in Black Sea turbot from this study were lower in the muscle samples compared with the studies conducted in Turkey, suggesting that the anthropogenic activity in the studied area did not pose a major impact upon the habitat contamination.

The distribution distance of polycyclic aromatic hydrocarbons in the tundra zone under the impact of thermal power plant

Being widely distributed in the tundra zone and highly sensible to temporal or spatial changes in composition of polycyclic aromatic hydrocarbons (PAHs) in ecosystems, Pleurozium schreberi Brid. can serve a pollution indicator of tundra biocenoses with polyarenes. The purpose of the present study is estimating the PAH distribution distance in the tundra zone under the impact of thermal power plant (TPP). The study was conducted in the Bolshezemelskaya tundra area of the Vorkuta region (Komi Republic, Russia). The surface accumulation and total content of PAHs in Pleurozium schreberi and organic horizon of tundra surfacegley soils (Stagnic Cambisols) at the background site and sites removed from the TPP at 0.5; 1; 1.5; 3; 5 and 12 km were studied. The PAH content in Pleurozium schreberi under the impact of TPP changes with distance not linearly. The maximum accumulation was noted at 3 km distance, then the content of PAHs decreased and reached a background level of 12 km from the source. The high molecular weight structures seemed to be transported at distance of no more than 3 km and fell down to the moss surface. The light structures could fly further. This fact responded for concentration of heavy and light structures on particles with different diameter. The moss surface at the background and polluted sites did not contain naphthalene. The total polyarene capacity on the moss surface is relatively the same for the background and polluted sites. At 3 km site, there was a sharp increase in the mass fraction of surface PAH by a factor of 3 due to an increase in the mass fraction of 4-5 - nuclear polyarenes. Being contaminated, the moss activates the bioaccumulation processes of PAHs and so transports polyarenes from its surface to inner organs. The exclusion is a site at a distance of 3 km where the proportion of surface accumulation increased with maximum pollution, i.e., PAH ingress into moss decreased. Determined that the dead part of Pleurozium schreberi or the whole plant is to be used for true identification of polyarenes. The changes in polyarene content in organic soil horizons are the same as in Pleurozium schreberi . By the obtained data, PAHs in tundra can move at large distances. The background-like PAH values are estimated for the site as 12 km from the pollution source for Pleurozium schreberi . The background-like PAH values for organic soil horizons are not estimated. The obtained results agree with the cluster analysis data.

Mercury dynamics in macroinvertebrates in relation to environmental factors in a highly impacted tropical estuary: Buenaventura Bay, Colombian Pacific

The environmental health of Buenaventura Bay, a highly impacted tropical estuary, is influenced by numerous human activities, including mining upstream. Large- and small-scale fishing plays an important role in the local economy, so we investigated the dynamic processes of bioaccumulation of mercury at basal trophic levels. Four samples were taken at each of the four locations in Buenaventura Bay during each of the four seasons of 2015. We measured the total mercury content (T-Hg, dry weight) in sediments and in muscle tissue across 17 macroinvertebrate species. The most abundant were the blue crab (C. arcuatus) and the mantis shrimp (S. aculeata aculeata). Blue crab showed an average muscle T-Hg value ​​exceeding the limit of 0.2 g·g-1, which is the maximum T-Hg level suggested for food consumption by vulnerable humans and populations: pregnant women, children, and the community that feeds from this source of protein on a daily basis. It was found that, 6.22% of individuals exceeded the 0.5 g·g-1 level, which is the maximum T-Hg level suggested for food consumption by the general population: the population that consumes it sporadically. Significantly high values ​​of T-Hg in blue crab and mantis shrimp occurred during low salinity conditions in the estuary, suggesting that Hg mainly originates from river runoff during the rainy season. Nevertheless, the biota-sediment accumulation factor (BSAF) was favored in high salinity, which could mean greater availability of Hg for higher levels of the estuarine food web in the dry season and in marine waters. In general, the T-Hg levels in some samples exceeded 0.2 g·g−1. Therefore this pollutant must be monitored due to its biomagnification potential and as a threat to human health, especially that for the local population of fishermen and their families.

A new pseudo-partition coefficient based on a weather-adjusted multicomponent model for mushroom uptake of pesticides from soil

In this study, a weather-based multicomponent model was developed based on the unique biostructures and metabolic processes of mushrooms to evaluate their uptake of pesticides from soils, and the effects of temperature and relative humidity on the bioaccumulation of pesticides in mushrooms was comprehensively quantified. Additionally, a new pseudo-partition coefficient between mushrooms and soils was introduced to assess the impacts of different physiochemical properties on the pesticide uptake process. The results indicate that, in general, the pseudo-partition coefficient increases as the relative humidity increases for both the air and soil according to Fick’s law of gas diffusion and the spatial competition of molecules, respectively. Meanwhile, the effect of temperature on the pesticide bioaccumulation process is more complex. For most pesticides (e.g., atrazine), the pseudo-partition coefficient that was computed from the transpiration component had a maximum value at a specific temperature due to the temperature dependency of the transpiration and biodegradation processes. For some pesticides (e.g., ethoprophos), the pseudo-partition coefficient of the air-deposition component had a maximum value at a certain temperature that was caused by the ratio of the soil–air internal transfer energy and degradation activation energy of the pesticide. It was also concluded that for relatively low-volatility pesticides, transpiration dominated the bioaccumulation process; this was mainly determined from the pesticide water solubility. For nonbiodegradable pesticides (e.g., lindane), the computed coefficient values were relatively low due to their insolubility in water, which inhibits bioaccumulation in mushrooms and is one of the main reasons for their long-term persistence in soils.

REVIEW POTENSI TANAMAN OBAT AKAR WANGI (Vetiveria Zizanioides) SEBAGAI TANAMAN HIPERAKUMULATOR DALAM FITOREMIDIASI PADA LAHAN TERCEMAR LOGAM.

Increased population growth results in increasing human needs over time. Meeting the high needs triggered the development of industries that meet the needs. Problems arise from the many industries that emerge, one of which is an environmental problem. Many industries in Indonesia have not used good waste treatment standards, causing pollution from the rest of the production process in the industry, one of which contains heavy metals such as Pb, Zn, Mercury and so on. Heavy metal is a type of pollutant that is harmful to plants, animals and humans through the process of bioaccumulation in the food chain. The purpose of this research is the content of heavy metals that are harmful to the sustainability of ecosystems in the environment requires a long time so that one way to prevent heavy metal compounds that can be released to the environment is by managing the bioremediasi process with fragrant root medicinal plants (Vetiveria Zizanioides) which has hyperaccumulator properties which can absorb one of the heavy metals namely Cadmium (Cd) and Lead (Pb).

Characteristics of the bioaccumulation process of mercury in the benthic ecosystem in the enclosed coastal seas

Characteristics of the bioaccumulation process of mercury in the benthic ecosystem in the enclosed coastal seas

Viral uptake and stability in Crassostrea gigas oysters during depuration, storage and steaming.

More stable than bacteria in environmental samples, enteric viruses are generally related to outbreaks of gastroenteritis caused by the consumption of contaminated oysters. This study evaluated: i) the dynamic processes of enteric viral models bioaccumulation by Crassostrea gigas oysters artificially contaminated; ii) the stability of these viruses in oysters in controlled temperature conditions and iii) the effect of UV light in inactivating these viruses in depurated oysters. Plaque assay (PA) was used to assess the infectivity of both viral models. Cell culture coupled with RT-qPCR (ICC-RT-qPCR) was used to measure infectious adenovirus type 2 (HAdV-2) genomes and qPCR to measure genome copies of murine norovirus (MNV-1). The virus uptake through bioaccumulation behave differently: HAdV-2 reached its peak of uptake faster than MNV-1. Both viruses showed high stability in oysters when maintained under 4 °C, but were completely inactivated in steamed oysters. The HAdV-2 was completely inactivated after 12 h of depuration with UV light and after 24 h without UV light. After 72 h of depuration, MNV-1 was still detected in both tanks, probably due to the stronger interaction of this virus with the oyster's tissues. This study demonstrated the importance of a secure depuration time in ensuring a clean and safe product, and that the steaming process is the safest way to prepare oysters for consumption.

Role of Curtobacterium herbarum strain CAH5 on aluminum bioaccumulation and enhancement of Lactuca sativa growth under aluminum and drought stresses

Aluminum (Al) bioaccumulation by a novel Al and drought tolerant Curtobacterium herbarum strain CAH5 isolated from rhizosphere soil of Beta vulgaris grown in acidic Andisols were examined. The rhizobacterial strain also presented important plant growth promoting traits even with Al and drought stresses under in-vitro conditions in broth. In experiments with a 2–6 mM as initial Al concentrations, the percentages of Al removal by bacteria were 89–93% and 78–91% within 72 h incubation under the normal and drought conditions, respectively. Cytogenotoxicity assay revealed that the toxicity of Al was reduced after bioaccumulation process. In the greenhouse study, formulated bio-inoculant CAH5 significantly improves the Lactuca sativa growth under Al and drought stress by reducing oxidative stress, lipid peroxidation and Al accumulation in plant parts. Our results highlighted that strain CAH5 could be used as a promising bioresource for restoration of agricultural soil with presence of phytotoxic Al improving crop production even under drought conditions.

Metal ions removal from different type of industrial effluents using Spirulina platensis biomass

The biomass of the cyanobacterium Spirulina platensis was used for metal removal from four industrial effluents with different chemical composition. The process of metal bioaccumulation (alive biomass) and biosorption (dry biomass) was studied at the native effluents pH as well as the pH 9.5. Metal uptake by S. platensis biomass was determined by means of neutron activation analysis (NNA). The obtained results show different affinity of biomass to metals presented in effluents. The results of this study have indicated that S. platensis is a very good candidate for the removal of heavy metals from complex industrial effluents.

Stabilization of hydrophobic organic contaminants in sediments by natural zeolites: bioavailability-based assessment of efficacy using equilibrium passive sampling

As natural zeolites have been widely used as cost-effective adsorbents for plant nutrients and heavy metals in sediments, it is worthwhile to verify the potential of natural zeolites for mixed-contaminant stabilization including hydrophobic organic contaminants (HOCs). The effectiveness of natural zeolite amendment in sediment on reducing the bioaccumulation of sediment-associated HOCs in V. philippinaram (Cb) was assessed. Then, the role of sediment pore water freely dissolved HOCs (Cfree) in Cb prediction was further identified and modeled. In this study, a bioavailability-based assessment of the HOC-stabilization efficacy of natural zeolites in maricultural sediments was performed using equilibrium passive sampling. V. philippinaram was adopted as a biological indicator for HOC bioaccumulation. Polydimethylsiloxane (PDMS) was used as a passive sampler for monitoring the concentration of the Cfree. The assumption that Cfree is a central mediator driving the bioaccumulation process of HOCs from the bulk sediment to the exposed organisms was validated by correlating the reductions in Cb and Cfree of the sediments amended with natural zeolites. Subsequently, a model based on this assumption was built and verified for the bioavailability-based assessment of the stabilization efficacy of natural zeolite amendment on sediment-associated HOCs. The results showed the bioaccumulations of four kinds of HOCs (including polycyclic aromatic hydrocarbons, polybrominated diphenyl ethers, pyrethroids, and organochlorine pesticides) in V. philippinaram were reduced by 7.3–38% after the natural zeolite amendment (10% dry weight in sediments), and the Cfree values measured with PDMS were reduced proportionally. It supported the assumption that Cfree is a central mediator driving the bioaccumulation process of HOCs. Kow of HOCs and two properties of sediment were found to be significantly correlated with the reductions of the Cfree values. Based on these findings, a model to predict the Cb values of PAHs and PBDEs in V. philippinaram was built. The model was then verified by a significant correlation between the predicted and measured values of Cb. The potential of natural zeolites for the stabilization of mixed-contaminants in sediments, including HOCs, was proved as notable reductions of Cb and Cfree of HOCs in the sediments amended by natural zeolite were observed. The results also suggested PDMS is a promising tool for predicting the bioaccumulation of sediment-associated HOCs in V. philippinaram and further for assessing the stabilization efficacy of natural zeolites in maricultural sediments. Modifying natural zeolites to further improve the effectiveness of HOC stabilization is warranted.

Bioaccumulation of Mercury in the Copepod Pseudodiaptomus marinus: A Comparative Study Between Waterborne and Dietary Pathways

The fate and the accumulation kinetics of mercurychloride (HgCl2) were investigated in the invasive copepod species Pseudodiaptomus marinus, which originates from the North-Western Pacific Ocean and was recently recorded from the Atlantic and Mediterranean coasts. The main objective of this study was to determine lethal concentrations (LC50 %) of HgCl2 in P. marinus and to study its bioaccumulation kinetics in the laboratory. Lethality experiments were performed for 24, 48, 72, and 96 h. Experiments in presence and absence of food source using one sub-lethal concentration of HgCl2 (14.15 μg/L) were carried out to study the uptake, the accumulation and the influence of exposure pathways of HgCl2 in P. marinus. LC50 for 96 h was calculated as 42.4 μg/L in response to HgCl2. The uptake and bioaccumulation kinetics of HgCl2 in P. marinus are not depending on the exposure pathways, where no significant differences were depicted between the uptake/accumulation of HgCl2 from the micro-algal diet and from the seawater medium. Those results could be helpful in the understanding of mercury uptake, bioaccumulation and bio-amplification processes especially concerning invasive copepod species.

The Potential of Bacillus cereus S1 as an Environmentally Friendly Bioaccumulator of Gold Nanoparticle Waste

Gold (Au) is one of the metals that is widely used for jewellery and electroplating. Although in the nanoparticle form, the waste that produced still has high economic value. Since its belong to heavy metals, gold nanoparticle waste need to be removed even in the very low concentration. One of the alternatives is utilized gold-resistant bacteria, namely Bacillus cereus S1. The purpose of our study was to determine the ability of B. cereus S1 to accumulates gold. Reconfirmation test of B. cereus S1 gold resistant ability was figured out using Minimal Salt Medium (MSM), 2% glucose and 0.1 ppm gold. The bioaccumulation process was used 1 ppm, 5 ppm, and 10 ppm concentration of gold; and the incubation periods were 6, 12, and 24 hours. Gold bioaccumulation performed by B. cereus S1 was measured using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-EOS). The results showed that the longer incubation periods of B. cereus S1, the higher gold concentration will be accumulated at exposure concentration 1 ppm, 5 ppm and 10 ppm. B. cereus S1 showed good viability after 24 hours metal exposure.

The Haematococcus pluvialis extract enriched by bioaccumulation process with Mg(II) ions improves insulin resistance in equine adipose-derived stromal cells (EqASCs)

Insulin resistance (IR) is one of the characteristic features of equine metabolic syndrome (EMS). Presently, the only therapies of choice are caloric restrictions combined with mineral supplementation, which might improve insulin sensitivity. In this study we investigated the effect of Haematococcus pluvialis algae water extract enriched in bioaccumulation process in magnesium ions (Hp_Mg(II)) on equine adipose derived mesenchymal stromal stem cells, in which insulin resistance was induced by palmitic acid (IR-EqASCs). For this purpose, chemical characterization of H. pluvialis was performed with special emphasis on the analysis of minerals composition, total phenolic and carotenoids contents, as well as scavenging activity. To examine the influence of H. pluvialis extract on IR-EqASCs, various methods of molecular biology and microscopic observations (i.e., immunofluorescence staining, SEM, gene expression by RT-qPCR, proliferative and metabolic cells activity analysis) were applied to investigate in vitro viability, oxidative stress markers and apoptosis-related factor accumulation, along with insulin resistance-related genes expression. Obtained results show, that Hp_Mg(II) significantly improves proliferative and metabolic activity of IR-EqASCs, shortens their population doubling time, improves their clonogenic potential and reduces expression of apoptosis related genes. Moreover, anti-oxidative effect of extract was presented.

Trophic position and individual feeding habits as drivers of differential PCB bioaccumulation in fish populations

Despite PCBs being banned since the 1980's, some European peri-alpine lakes, and consequently their fish populations, are still contaminated by these xenobiotics. We investigated the relative contribution of physiological and trophic factors that could be implicated in fish PCB bioaccumulation in Lake Bourget (France), one of the most contaminated in Europe, by collecting Arctic char (n = 55) and European whitefish (n = 89) from 2013 to 2016. Concentrations of 7 indicator PCBs were 9–168 ng.g w.w−1 in whitefish and 90–701 ng.g w.w−1 in Arctic char. The fish trophic positions calculated from δ 15N values were positively correlated with PCB concentrations (r2 = 0.45; p < 0.001). A biomagnification model relying on TP and lipid content of fish was then designed, and it confirmed this result. A Bayesian mixing model based on δ 13C and δ 15N values was used to estimate the relative contribution of preys in the fish diet, which explained a significant proportion of the biomagnification model residuals (i.e., 17%). Zooplankton consumption was negatively correlated with PCB concentrations, whereas consumption of chironomids enhanced the PCB burden in fish. Correction of the biomagnification model for individual diets of fish increased the correlation between the predicted and measured fish PCB contents (R2 = 0.71; p < 0.001), highlighting the importance of fish feeding habits in the bioaccumulation process.

Research on Improving Fertility Sandy Soils from Dabuleni Field by Administration of Loess

In order to solve and clarifying certain aspects of the clay content (particles [0.002 mm) sands and sandy soils, humus, respectively, the process of bioaccumulation and mineralization the organic matter of the land, in the Research and Development Centre for Plant Growing on Sand Dabuleni, have initiated research aimed at finding methods and means for accumulating and thus the increase in the content of clay in the soil, respectively humus.Therefore, to improve radical of sandy soils, we found it necessary to resort to what is called loess process. It consists in enriching the horizon the surface soil (20-25 cm) the fraction with 8-10% clay, to 1.5-5%, as currently it contains. It is primarily intended to influence various amounts loess material on physical, hydro- physical and chemical properties of soils, then the plant response to changes products in the soil, increasing the guaranteed potential fertility of these soils, which will result in production high and constant.Obtaining appropriate agricultural production on sandy soils (eutric psamosol) it is limited not only by the soil, but also other factors such as relief, drainage and even climate. Because coarse texture, water-holding capacity in the case of sandy soils it is very low in all soils, the clay content below 5% production capacity of soils it is particularly low in the absence of agropedoameliorative measures and especially irrigation. Wind erosion occurs in all perimeters sandy soils, with higher intensity is observed in Oltenia Plain (Dabuleni Field).