The toxic effects of herbicides (Machete, Saturn) and pesticides (Diazinon and Malathion) on green algae, Scenedesmus obtusiusculus, and cyanobacteria, Anabaena flos aquae, were studied. The results indicated that Machete and Saturn, in comparison to Diazinon and Malathion, were more toxic. On the other hand it was revealed that green algae was more sensitive to the pesticides than the cyanobac...

Cyanobacteria are considered a promising source for new ‎pharmaceutical lead compounds and a large number of chemically diverse and ‎bioactive metabolites have been obtained from cyanobacteria. Despite of ‎several worldwide studies on prevalence of NRPSs and PKSs among the ‎cyanobacteria, none of them included Iranian cyanobacteria of Kermanshah ‎province. Therefore, the aim of this study was t...

The toxic effects of herbicides (Machete, Saturn) and pesticides (Diazinon and Malathion) on green algae, Scenedesmus obtusiusculus, and cyanobacteria, Anabaena flos aquae, were studied. The results indicated that Machete and Saturn, in comparison to Diazinon and Malathion, were more toxic. On the other hand it was revealed that green algae was more sensitive to the pesticides than the cyanoba...

Biological nitrogen (N) fixation, the microbial conversion of N2 gas to ammonia, makes N available food webs. Low-N streams often have a high relative abundance N-fixing taxa, suggesting that fixation is an important source in these systems. Despite this potential, stream has not been well-characterised, particularly compared lakes and marine environments. One unknown contributions various orga...

The regulation of glutamine synthetase (EC 6.3.1.2) from Prochlorococcus was previously shown to exhibit unusual features: it is not upregulated by nitrogen starvation and it is not inactivated by darkness (El Alaoui et al. (2001) Appl Environ Microbiol 67: 2202-2207). These are probably caused by adaptations to oligotrophic environments, as confirmed in this work by the marked decrease in the ...

Trichodesmium sp. is a filamentous, colonial cyanobacterium which contributes substantially to the input of nitrogen in tropical and subtropical oceanic waters through nitrogen fixation (N(2) fixation). We applied a N tracer technique to assess the rate of release of dissolved organic nitrogen (DON) from this cyanobacterium and compared those rates with rates of N(2) fixation determined for the...

 The main goal of this study was to examine the use of cyanobacteria for evaluating the quality of running water. Accordingly epilithic cyanobacterial communities were collected in Dez River and Ojeyreb drain in south of Iran. Samples were collected in two seasons: autumn and spring. Effective physical and chemical factors on the structure of cyanobacterial communities and the dispersi...

conclusions the results of the present study revealed that soil resources of these areas were contaminated with opportunistic amoebas such as acanthamoeba and hartmannella spp. and this may lead to severe diseases in high-risk people, such as immunocompromised patients. background free-living amoebas are very abundant in nature, especially in water and soil. some species of amoebas cause seriou...

Cyanobacteria are an important part of phytoplankton communities, however, they also known for forming massive blooms with potentially deleterious effects on recreational use, human and animal health, ecosystem functioning. Emerging high-frequency imaging flow cytometry applications, such as Imaging FlowCytobot (IFCB), crucial in furthering our understanding the factors driving bloom dynamics, ...

Cyanobacteria-plant symbioses play an important role in many ecosystems due to the fixation of atmospheric nitrogen (N) by the cyanobacterial symbiont. The ubiquitous feather moss Pleurozium schreberi (Brid.) Mitt. is colonized by cyanobacteria in boreal systems with low N deposition. Here, cyanobacteria fix substantial amounts of N₂ and represent a potential N source. The feather moss appears ...