ANTIMICROBIAL PROPERTIES OF SEVEN BROWN ALGAE HARVESTED FROM THE COAST OF SIDI BOUZID (EL JADIDA-MOROCCO)

Objective: This work aims at the screening of the antimicrobial activity of the seven brown marine algae of theCoast of Sidi Bouzid (El Jadida-Morocco). Methods: The aim of this study was to evaluate the antimicrobial activity of seven brown marine algae against three Gram-positive bacteria (Staphylococcus epidermidis, Staphylococcus aureus and Streptococcus pyogenes). Three Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia) and two fungi (Aspergillus Niger and Candida tropicalis). Thus, 35 algal extracts were prepared with five organic solvents methanol/water, methanol, dichloromethane/methanol, dichloromethane and ethyl acetate. The antibacterial activity was evaluated through the disk diffusion method. Results: Data revealed that the Staphylococcus aureus bacteria was the most sensitive pathogen by showing the highest zone of inhibitions of 20 mm with the lowest Minimum Inhibitory Concentration (MIC) of 2 μgmL⁻¹ methanol/water extract of Cystoseira tamariscifolia. Whereas, antifungal activity, the highest zone of inhibitions of 21 mm and 22 mm with the lowest Minimum Inhibitory Concentration (MIC) of 5 μgmL-¹ was respectively shown in the methanol/water extract of Laminaria ochroleuca against Candida tropicalis and in the dichloromethanolic extract of Sargassum vulgare against Aspergillus niger. Conclusion: The results indicate that these algal extracts can further be analyzed and purified for relevant antibacterial and antifungal compounds which can be used in therapeutics and other applications.