Publications by authors named "Ranya Amer"

Article Synopsis
  • Antibiotic contamination in the Litani River, a heavily polluted river in Lebanon, was studied, focusing on amoxicillin, ciprofloxacin, and azithromycin, with a thorough analysis of water quality and microbial resistance.
  • Analysis showed amoxicillin and ciprofloxacin were present at 250 ng/L and 107.2 ng/L respectively, while azithromycin was not detected; significant levels of antibiotic-resistant bacteria like E. coli and Pseudomonas aeruginosa were also identified.
  • Although various water quality parameters exceeded safe levels, the ecological risk assessment indicated that the presence of these antibiotics poses a low risk to the environment.
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In this work, the efficiency of a conventional chlorination pretreatment is compared with a novel modified low-fouling polyethersulfone (PES) ultrafiltration (UF) membrane, in terms of bacteria attachment and membrane biofouling reduction. This study highlights the use of membrane modification as an effective strategy to reduce bacterial attachment, which is the initial step of biofilm formation, rather than using antimicrobial agents that can enhance bacterial regrowth. The obtained results revealed that the filtration of pretreated, inoculated seawater using the modified PES UF membrane without the pre-chlorination step maintained the highest initial flux (3.

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Nostoc sp. is one of the most widely distributed cyanobacterial genera that produce potentially protein phosphatase (PP) inhibitor; microcystins (MCs). MCs have posed a worldwide concern due to predominant hepatotoxicity to human health.

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Pesticides occupy a critical position among many chemicals to which man can be exposed; their diffusion into the environment causes killing and damaging of some forms of life. The lack of highly selective pesticide action represents risk both for man and other desirable forms of life present in the environment. The present study was designed to evaluate the relation between exposure to pesticides and disorder on hematological parameters and kidney function of male agricultural workers with the mean age 37.

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Coastal environments worldwide are threatened by the effects of pollution, a risk particularly high in semienclosed basins like the Mediterranean Sea that is poorly studied from bioremediation potential perspective especially in the Southern coast. Here, we investigated the physical, chemical, and microbiological features of hydrocarbon and heavy metals contaminated sediments collected at El-Max bay (Egypt). Molecular and statistical approaches assessing the structure of the sediment-dwelling bacterial communities showed correlations between the composition of bacterial assemblages and the associated environmental parameters.

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Two of the largest crude oil-polluted areas in the world are the semi-enclosed Mediterranean and Red Seas, but the effect of chronic pollution remains incompletely understood on a large scale. We compared the influence of environmental and geographical constraints and anthropogenic forces (hydrocarbon input) on bacterial communities in eight geographically separated oil-polluted sites along the coastlines of the Mediterranean and Red Seas. The differences in community compositions and their biodegradation potential were primarily associated (P < 0.

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Uric acid is a promising hydrophobic nitrogen source for biostimulation of microbial activities in oil-impacted marine environments. This study investigated metabolic processes and microbial community changes in a series of microcosms using sediment from the Mediterranean and the Red Sea amended with ammonium and uric acid. Respiration, emulsification, ammonium and protein concentration measurements suggested a rapid production of ammonium from uric acid accompanied by the development of microbial communities containing hydrocarbonoclastic bacteria after 3 weeks of incubation.

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Optimized denaturing gradient gel electrophoresis (DGGE) fingerprinting and real-time PCR were performed to identify and quantify the potential hepatotoxic microcystin- and nodularin-producing cyanobacteria present in freshwater samples collected during different seasons at three different sites from the Nile River Delta. The combined use of molecular gene markers (targeting the aminotransferase domain of the hepatotoxin synthetase modules and the 16S rRNA gene) and light microscopy demonstrated the dominance of different freshwater Microcystis phylotypes, including the potential hepatotoxin producers M. wesenbergii and M.

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