Assessment of antibacterial activity, modes of action, and synergistic effects of Origanum vulgare hydroethanolic extract with antibiotics against avian pathogenic Escherichia coli.

This study evaluates the antibacterial effectiveness of Origanum vulgare hydroethanolic extract, both independently and in combination with antibiotics, against Escherichia coli strains associated with avian colibacillosis-a significant concern for the poultry industry due to the rise of antibiotic-resistant E. coli. The urgent demand for new treatments is addressed by analyzing the extract's phytochemical makeup via High-Performance Liquid Chromatography (HPLC), which identified sixteen phenolic compounds.

What are the growth kinetics and biochemical compositions of microalgae isolated from diverse aquatic ecosystems in Morocco, France, and Tunisia?

Thirty-six microalgae belonging to five taxonomic groups (Cyanobacteria, Chlorophyceae, Diatomophyceae, Euglenophyceae, and Eustigmatophyceae) were identified from six freshwater ecosystems in Morocco, two treatment stations in Etueffont landfill in France and three hot spring waters in Tunisia. Investigations on species growth kinetics and growth rates showed that the cyanobacterium Leptolyngbya gelatinosa exhibited both the highest biomass and growth rate with 4 g L and 0.282 day, respectively.

Assessing the status of Ichkeul Lake and its catchment through identifying potentially toxic cyanobacteria, simultaneously extracted metals and use of acid-volatile-sulfide model.

Lake Ichkeul is considered one of the most significant wetlands in the Mediterranean basin. It serves as a crucial wintering area for numerous western Palearctic birds. A notable decline in species diversity has been observed in the past decade, attributed to excessive water usage for irrigation and the effects of climate change.

Assessment of single and combined effects of bisphenol-A and its analogue bisphenol-S on biochemical and histopathological responses of sea cucumber Holothuria poli.

Bisphenols (BPs) are among emerging pollutants that have been frequently detected in different compartments of marine ecosystems and elicited great concern due to their potential toxicity to marine organisms. This work aimed to investigate the toxicity of bisphenol A (BPA) and bisphenol S (BPS) on oxidative stress markers, neurotoxicity and histopathological alterations in sea cucumbers (Holothuria poli). The results showed that exposure to 200 μg/L of BPA and BPS produced oxidative stress, neurotoxicity in the digestive tract and respiratory tree, and several types of histopathological lesions in tissues of the respiratory tree of the sea cucumber, posing a health hazard to this aquatic organism.

Assessment of trace elements and fluoride originating from phosphogypsum in the sediment of Gulf of Gabes (southeastern Tunisia): what are the potential sources of accumulation and bioavailability?

To assess potential impacts of industrial activities on the pollution status of Gulf of Gabes, twenty sediment and water samples along with phytoplankton enumeration were achieved at different stations with specific features. Comparing trace element concentrations in sediment to applicable SQG standards, we were intrigued by an accumulation of Zn, Cr, Ni, and especially Cd, which exhibited relatively high content compared to these standards. Moreover, trace metal bioavailability was high in front of industrial discharge areas.

Microalgae colonization and trace element accumulation on the plastisphere of marine plastic debris in Monastir Bay (Eastern Tunisia).

In this study, we examined the toxicity potential of the epiplastic microalgal community that developed on low-density polyethylene (LD-PE) plastic debris found in two distinct regions of the Monastir Bay (Tunisia): the coast exposed to anthropogenic discharges and the open sea in front of the Kuriat Islands. Concentrations of potentially toxic elements (PTEs) accumulated in sediments and plastisphere were compared in order to determine their toxicity potential to biological life. The collected plastispheres were predominantly composed of cyanobacteria, chlorophytes, and diatoms.

Occurrence and antibiotic resistance of Vibrio parahaemolyticus isolated from the Tunisian coastal seawater.

Vibrio parahaemolyticus is a gram-negative bacterium ubiquitous in seawater or estuarine water throughout the world. It is a major cause of seafood gastroenteritis complications. In this study, the presence of V.

Does thermal stress modulate the biochemical and physiological responses of Ruditapes decussatus exposed to the progestin levonorgestrel?

In this study, we investigated the effects of 1000 ng/l levonorgestrel (LNG) alone or combined with increased temperature of 20, 24, and 28 °C on the biochemical and physiological responses of the clam (Ruditapes decussatus) for 28 days. Our results revealed that female clams treated with levonorgestrel (LNG) alone showed enhancement of the antioxidant defense against oxidative stress related to the inductions of catalase (CAT), gluthatione -S -transferase (GST), and protein sulfhydryl (PSH), while the elevated temperatures of 20, 24, and 28 °C diminished most of the specific responses to LNG and was the main factor in the determining the responses to combine exposures. The responses of lysosomal membrane stability, alkaline phosphatase, and NADP-dependent isocitrate dehydrogenase detected were the most common signs of an adverse effect in all exposures.

Hydrology, biogeochemistry and metabolism in a semi-arid mediterranean coastal wetland ecosystem.

A LOICZ Budget Model is applied to the Ichkeul Lake, a wetland ecosystem of the South Mediterranean-North African region, to evaluate its functioning in order to boost water management. The Ichkeul Lake water and nutrient budget, net ecosystem metabolism (NEM), nutrient availability, and their seasonal changes are estimated using field data. A considerable anthropogenic-driven amount of nitrogen is transferred into N/NO to the atmosphere during the dry season with predominance of denitrification-anammox processes.

Application of the Paracentrotus lividus sea-urchin embryo-larval bioassay to the marine pollution biomonitoring program in the Tunisian coast.

The pollution of the marine environment by treated and untreated effluents has increased due to human activities. Monitoring the marine ecosystem is nowadays a global concern. In this work, we evaluated the effect of contaminated and uncontaminated seawater, from different Tunisian coastal areas, on the fertilization, gastrulation, and embryo-larval development events of sea urchins (Paracentrotus lividus).

Bisphenol A removal by the Chlorophyta sp.: optimization and kinetic study.

The Chlorophyta sp. isolated from a Tunisian household sewage pond appears promising for effective removal of Bisphenol A (BPA). Efficient and cost-effective technology for contaminants remediation relies on a tradeoff between several parameters such as removal efficiency, microorganism growth, and its tolerance to contaminant toxicity.

Enhancement of extracellular polymeric substances (EPS) production in Spirulina (Arthrospira sp.) by two-step cultivation process and partial characterization of their polysaccharidic moiety.

The interactive effects of light intensity and NaCl concentration were investigated for Spirulina two-step cultivation process using Full Factorial Design. In the experiment interval, light intensity had no effect while the NaCl concentration had significant effect on the enhancement of extracellular polymeric substances (EPS) production. Interestingly, results revealed a significant negative interaction between light and NaCl concentration indicating that high NaCl concentration (40gL) and low light intensity (10μmol photons ms) enhanced the EPS production.

Therapeutic properties in Tunisian hot springs: first evidence of phenolic compounds in the cyanobacterium Leptolyngbya sp. biomass, capsular polysaccharides and releasing polysaccharides.

Background: In Tunisia, the use of hot spring waters for both health and recreation is a tradition dating back to Roman times. In fact, thermal baths, usually called "Hammam" are recommended as a therapeutic and prophylactic measure against many types of illness and toxicity. While the chemical concentration of thermal water is admittedly associated with its therapeutic effects, the inclusion in spa waters of efficient bioproduct additives produced by photosynthetic microorganisms and that act against oxidative stress may comprise a significant supplementary value for thermal centers.

Prevalence of Biofilm Formation and Wide Distribution of Virulence Associated Genes among Vibrio spp. Strains Isolated from the Monastir Lagoon, Tunisia.

In the current study, 65 Vibrio spp. were isolated from the Monastir lagoon water, were characterized phenotypically and genotypically. In addition, we looked for the presence of three Vibrio parahaemolyticus virulence genes (tlh, trh and tdh) and ten Vibrio cholerae virulence genes (ctxA, vpi, zot, ace, toxR, toxT, tosS, toxRS, tcpA and cpP).

Partial characterization and antioxidant and antiproliferative activities of the aqueous extracellular polysaccharides from the thermophilic microalgae Graesiella sp.

Background: For thousands of years, Tunisian geothermal water has been used in bathing. Indeed, thermal baths "Hammam" were recommended in the treatment of different type of illnesses as, for instance, for relaxing joints and soothing. The ability of microalgae to sustain at the high temperature makes them potential producers of high value thermostable bio-products.

The effects of temperature and light intensity on growth, reproduction and EPS synthesis of a thermophilic strain related to the genus Graesiella.

Tunisian microalgae are diverse and rarely been studied. This study reports a first investigation of thermophile Chlorophyta isolated from mats community colonizing the geothermal springs in the north of Tunisia at water temperature 60 °C. In the study, the combined effect of temperature and light intensity was investigated on the cell growth, the mother and daughter cells abundance and the extracellular polymeric substances synthesis in batch culture of the isolated species.

Evaluation of Arthrospira platensis extracellular polymeric substances production in photoautotrophic, heterotrophic and mixotrophic conditions.

The kinetic study of Arthrospira platensis extracellular polymeric substances (EPS) production under different trophic modes-photoautotrophy (100 μmol photons m(-2) s(-1)), heterotrophy (1.5 g/L glucose), and mixotrophy (100 μmol photons m(-2) s(-1) and 1.5 g/L glucose)-was investigated.