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.

Harmful epiphytic dinoflagellate assemblages on macrophytes in the Gulf of Tunis.

The spatio-temporal distribution of epiphytic and planktonic microalgae coupled with environmental factors was investigated for a one-year period in the Gulf of Tunis (northeastern Tunisia). Harmful microalgae assemblages were dominated by three toxic epiphytic dinoflagellates: Ostreopsis sp., Prorocentrum lima and Coolia monotis.

Alexandrium pacificum Litaker sp. nov (Group IV): Resting cyst distribution and toxin profile of vegetative cells in Bizerte Lagoon (Tunisia, Southern Mediterranean Sea).

A high spatial resolution sampling of Alexandrium pacificum cysts, along with sediment characteristics (% HO, % organic matter (OM), granulometry), vegetative cell abundance and environmental factors were investigated at 123 study stations in Bizerte Lagoon (Tunisia). Morphological examination and ribotyping of cells obtained from a culture called ABZ1 obtained from a cyst isolated in lagoon sediment confirmed that the species was A. pacificum.

Phylogeny and biogeography of the invasive cyanobacterium Cylindrospermopsis raciborskii.

Cylindrospermopsis raciborskii is a toxic cyanobacterium with an invasive nature. The species is found in all the main continents but its origin and dispersal routes on a worldwide perspective remain yet mostly unknown. In this study, 27 isolates of C.

African origin and europe-mediated global dispersal of the cyanobacterium Microcystis aeruginosa.

Microcystis aeruginosa is a bloom-forming cyanobacteria, which currently has a cosmopolitan distribution. Since M. aeruginosa can produce toxic compounds across all continents that it inhabits, it is of major public health relevance to assess its origin and dispersal.

Molecular and phylogenetic characterization of potentially toxic cyanobacteria in Tunisian freshwaters.

This study presents a genetic characterization of 27 potentially toxic cyanobacterial strains isolated from seven reservoirs located in the north and centre of Tunisia. These strains belonged mainly to Microcystis aeruginosa, Cylindrospermopsis raciborskii and Planktothrix agardhii species. Their toxicological potential was evaluated by molecular biology tools, which showed that none of the isolated strains carried segments of the gene cluster responsible for the production of cylindrospermopsin and saxitoxin.

Genetic variability of the invasive cyanobacteria Cylindrospermopsis raciborskii from Bir M'cherga reservoir (Tunisia).

Cylindrospermopsis raciborskii is an invasive freshwater cyanobacteria of tropical origin, also found in temperate regions. Due to its known ability to produce potent toxins, such as cylindrospermopsin and the paralytic shellfish poisoning, this species is of major concern from a water quality perspective. This study presents a genetic characterization of four C.

Genetic diversity and structure of the invasive toxic cyanobacterium Cylindrospermopsis raciborskii.

Strains of the invasive toxic cyanobacteria Cylindrospermopsis raciborskii were genetically evaluated with four genetic markers encompassing in total 2.9 kb (16S rRNA, ITS longer spacer, ITS shorter spacer and rpoC1) to assess the phylogenetic relationships, genetic variation and population differentiation of the species across all five continents. The phylogenetic analysis showed that the C.

Seasonal occurrence and toxicity of Microcystis spp. and Oscillatoria tenuis in the Lebna Dam, Tunisia.

Physicochemical and biological water quality, including the total microcystin concentrations, was investigated for the first time from January to December 2005 in the Lebna Dam, Tunisia. Microcystin levels and characterization of the different microcystin variants present were measured by protein phosphatase (PP2A) inhibition assays and by LC/MS/MS, respectively. Nutrient values were high, with total inorganic nitrogen and phosphorus concentrations ranging from 0.