Abstract
This dissertation looks at the resistance to heavy metals of bacteria isolated from marine
environments influenced by human activity, and their potential for use in the bioremediation of
hexavalent chromium. Faced with increasing industrial pollution and the limitations of traditional
treatment methods, research is turning towards more sustainable and economical biological solutions.
The work was carried out on samples taken from the mouths of the El Harrach and El
Hamiz wadis, sites subject to heavy anthropogenic pressure. The results reveal a high microbial
load and variable resistance to heavy metals between the sites studied, which remains low overall. The bacteria isolated showed multiple resistance to heavy metals and antibiotics, with a predominance of Gram-negative bacteria. The study then examined the bioremediation potential of
hexavalent chromium in three selected strains (Klebsiella pneumoniae, Staphylococcus aureus,
Pseudomonas aeruginosa), by examining the influence of various parameters (inoculum, pH and
chromium concentration) on their effectiveness. The results were promising and the strains demonstrated their ability to eliminate chromium.
Key words : heavy metals, resistance, bacteria, chromium removal, bioprocessing
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