Résumé:
The diversity of living marine world offers a substantial potential for the exploitation and the
discovery of bioactive natural substances. Within this considerable chemodiversity,
continually exposed to the surrounding marine invertebrates pathogenic microorganisms and
only provided with a primitive immune system, without memory, represent a single reservoir
of bioactive molecules defenses. This work aims to explore the antimicrobial properties of
bioactive substances, and hemolymph peptide fraction of the mussel (Mytilus
galloprovincialis) of the Mostaganem region. The protein content was assayed by the Lowry
method. The antimicrobial activity was tested vis-a-vis a reference range of microorganisms
using the microdilution method. The results obtained showed that the protein content
increases with mold contamination by E. Coli, also hemolymph has a higher antimicrobial
potency compared to peptides. It turned out that the S. aureus strain is the strain sensitive to
the action of the hemolymph with MIC of 0.7177 g / ml. As regards the results of the peptide
moiety, the behavior of stem was different. The S. typhimurium strain was the most sensitive
strain with an MIC of 0.1495 g / ml. All these results suggest that substances associated with
the immune system may play a critical role in the defense of bivalves.
