COMPARATIVE STUDY ON THE ANTIMICROBIAL ACTIVITY OF ORGANIC EXTRACTS OF TWO SEAWEEDS: STYPOCAULON SCOPARIUM AND HALOPITYS INCURVUS.

Six organic and aqueous extracts of two marine algae Stypocaulon scoparium and Halopitys incurvus were collected and studied from the Algerian west coast for their antimicrobial activities against Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli), Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus) and fungi (Candida albicans, Fusarium oxysporum f. sp. albedinis). The positive antibacterial activity with more than 10 mm diameter of inhibition zone was found by the ethanolic toluene extracts and the extract obtained by the Ethanol/Chloroform mixture of the two algae. Also, the results of the antifungal tests against Fusarium oxysporoum f. sp. albedinis have shown that the best results were obtained by the aqueous, methanol/dichloromethane and ethanolic extracts of the two algae. The methanolic and toluene extracts of Halopitys incurvus were very active with mycelial growth inhibition rates of 60% and 50%, respectively. The purification and the determination of chemical structure of active compounds from the two algae yet to be. [ABSTRACT FROM AUTHOR]