Elucidating metabolic pathways through genomic analysis in highly heavy metal-resistant strains.

The annotated and predicted genomes of five archaeal strains (AS1, AS2, AS8, AS11 and AS19), isolated from Sfax solar saltern sediments (Tunisia) and affiliated with , were performed by RAST webserver (Rapid Annotation using Subsystem Technology) and NCBI prokaryotic genome annotation pipeline (PGAP). The results showed the ability of strains to use a reduced semi-phosphorylative Entner-Doudoroff pathway for glucose degradation and an Embden-Meyerhof one for gluconeogenesis. They could use glucose, fructose, glycerol, and acetate as sole source of carbon and energy.

Influence of localized sources and meteorological conditions on dry-deposited particles: A case study of Gabès, Tunisia.

This study investigates the spatial and temporal variations of dry-deposited particles on the surface (by turbulence or gravity) in various sites within Gabès city and its surroundings, South-eastern Tunisia. Monthly samples were collected from five distinct locations: suburban-industrial (S2), suburban-residential (S3), and urban sites (S1, S4, and S5). The average monthly particle deposition flows ranged from 7.

Glyphosate and other plant protection products in size-segregated urban aerosol: Occurrence and dimensional trend.

Plant protection products (PPPs) play a fundamental role in the maintenance of agricultural fields and private/public green areas, however they can contaminate zones nearby the application point due to wind drift, resuspension, and evaporation. Several studied have deepened the relationship between PPPs and living beings' health, suggesting that these products might have a negative influence. Some PPPs belong to the class of Emergent Contaminants, which are compounds whose knowledge on the environmental distribution and influence is limited.

Analysis of Daily and Diurnal O-NO Relationships and Assessment of Local/Regional Oxidant (OX = O + NO) Levels and Associated Human Health Risk at a Coastal Suburban Site of Sfax (Tunisia).

The present study investigated the temporal variability of surface ozone and its nitrogen precursors at the proximity of a traffic crossroad (≈ 22,580 vehicles per day) located in a coastal suburban site of Sfax city (Tunisia). It was performed during January-October, 2010. The study results show that the surface ozone is characterized by a slightly modulated regime between day and night.

Hydrolytic enzyme screening and carotenoid production evaluation of halophilic archaea isolated from highly heavy metal-enriched solar saltern sediments.

This paper aimed to screen the enzymatic activities and evaluate the carotenoid production level of twenty-two halophilic archaea isolated from Sfax solar saltern sediments. The molecular identification performed by sequencing the 16S rRNA genes showed that all strains have a high similarity degree (99.7-100%) with Halobacterium salinarum NRC-1.

Genomic analysis of heavy metal-resistant Halobacterium salinarum isolated from Sfax solar saltern sediments.

The draft genome sequences of five archaeal strains, isolated from Sfax solar saltern sediments and affiliated with Halobacterium salinarum, were analyzed in order to reveal their adaptive strategies to live in hypersaline environments polluted with heavy metals. The genomes of the strains (named AS1, AS2, AS8, AS11, and AS19) are found to contain 2,060,688; 2,467,461; 2,236,624; 2,432,692; and 2,428,727 bp respectively, with a G + C content of 65.5, 66.

Resistance of a Halobacterium salinarum isolate from a solar saltern to cadmium, lead, nickel, zinc, and copper.

The current study focuses on the tolerance of a strain of Halobacterium salinarum isolated from Sfax solar saltern (Tunisia) towards cadmium (Cd), lead (Pb), nickel (Ni), zinc (Zn), and copper (Cu) by using agar dilution methods in complex and minimal media. The results showed the least inhibitory metals based on Minimum Inhibitory Concentrations (MICs) were lead (MIC = 4.5 mM), cadmium (MIC = 4 mM), and nickel (MIC = 2.

Spatial and temporal variations of dust particle deposition at three "urban/suburban" areas in Sfax city (Tunisia).

Particle deposition in three selected "urban/suburban" sites in Sfax city, southern Tunisia, was studied through biweekly monitoring particulate deposits from April 12 to November 26, 2014. Two sites (S1 and S2) were located at the proximity of well-exposed cross-roads; however, the third (S3) was located at a street canyon. A very high fluctuation in those particle fluxes, ranging from 0.

Geochemical behaviour of PM10 aerosol constituents under the influence of succeeding anticyclonic/cyclonic situations: case of Sfax City, southern Tunisia.

The present study investigates the geochemical behaviour of PM10 aerosol constituents (Cl, Na, Si, Al, Ca, Fe, Mg, Mn, Pb, Zn, S) at Sfax City (Tunisia) under succeeding meteorological conditions, including short-lived anticyclonic, cyclonic and prolonged anticyclonic situations. The results revealed daily total concentrations fluctuating between 4.07 and 88.

Sediment Quality and Potential Toxicity Assessment in Two Open/Semiclosed Mediterranean Sea Areas: A Case Study of Sfax Coast (Tunisia).

The Gulf of Gabès (southeastern Tunisia), characterized by the abundance of halieutic resources, is nowadays facing strong anthropogenic pressures. This paper aims to assess and compare metallic pollution in two open/semiclosed areas bordering the coastline of Sfax (a part of the Gulf). The first area covers the outlet zone of many anthropogenic effluents of urban Sfax, whereas the second area, located at a distance of 15 km from the first one, was selected as being representative of numerous semiclosed areas bordering the Gulf that have served for harvesting clams.

Climatological aspects of aerosol physical characteristics in Tunisia deduced from sun photometric measurements.

Atmospheric and climatic data measured at Thala site (Tunisia) for a long-time period (1977-2001) are used to analyse the monthly, seasonal, and annual variations of the aerosol optical depth at 1 μm wavelength. We have shown that aerosol and microphysical properties and the dominating aerosol types depend on seasons. A comparison of the seasonal cycle of aerosol optical characteristics at Thala site showed that the contribution of long-range transported particles is expected to be larger in summer as a consequence of the weather stability typical of this season.

Assessment of sediment quality in the Mediterranean Sea-Boughrara lagoon exchange areas (southeastern Tunisia): GIS approach-based chemometric methods.

Concentrations of selected heavy metals (Cd, Pb, Zn, Cu, Mn, and Fe) in surface sediments from 66 sites in both northern and eastern Mediterranean Sea-Boughrara lagoon exchange areas (southeastern Tunisia) were studied in order to understand current metal contamination due to the urbanization and economic development of nearby several coastal regions of the Gulf of Gabès. Multiple approaches were applied for the sediment quality assessment. These approaches were based on GIS coupled with chemometric methods (enrichment factors, geoaccumulation index, principal component analysis, and cluster analysis).

Heavy metal concentrations in the surface marine sediments of Sfax Coast, Tunisia.

Sixty-seven surface marine sediment samples in the <63 μm fraction collected from the coast of Sfax (Tunisia) were analyzed by inductively coupled plasma-atomic emission spectrometry for seven heavy metals (Pb, Ni, Cu, Cr, Zn, Cd, and Fe). Metal concentrations were compared with natural values, marine sediment quality standards, and also with other results concerning sediments from several Mediterranean coasts. The study of their spatial distributions refined by complementary approaches including principal component analysis, enrichment factors, and geoaccumulation index showed a significant impact of multiple anthropogenic sources.

Time-dependent evolution of olive mill wastewater sludge organic and inorganic components and resident microbiota in multi-pond evaporation system.

The physico-chemical and microbiological characterizations of olive mill wastewater sludge (OMWS) were investigated in five OMW evaporation ponds of the open-pond system in Sfax (Tunisia), during the olive oil production period in 2004. Time-dependent changes in both physico-chemical parameters and the microbiota were investigated. Mathematical models and principal component analysis (PCA) were used to establish the correlations between the studied parameters.

Olive mill wastewater evaporation management using PCA method Case study of natural degradation in stabilization ponds (Sfax, Tunisia).

Olive mill wastewater (OMW) evaporation ponds management was investigated in five serial evaporation open-air multiponds of 50 ha located in Sfax (Tunisia). Physico-chemical parameters and microbial flora evolution were considered. Empirical models describing the OMW characteristic changes with the operation time were established and Principal Component Analysis (PCA) described the correlation between physico-chemical and biological parameters.