Cytotoxic Activities of Actinobacteria Isolated from the Saudi Habitats by the Brine Shrimp Lethality Assay

摘要

The recent studies have increased our interest in the cytotoxic activities of actinobacteria. In the present study, ten actinobacterial isolates were randomly selected from 56 isolated recovered from the Saudi habitats to be screened for their cytotoxic potential by the brine shrimp lethality assay. The isolates were subjected to fermentation for production of their secondary metabolites and then extracted by ethyl acetate. The crude extracts dissolved in methanol were used for the screening. The brine shrimp lethality test was condi'cted on each of the extracts at five different concentrations 5, 10, 25, 50 and 100 mug/ml. The extracts of the actinobacteria isolates showed IC 50 in the range from 4.56 to 88.38ug/ml. Based on their characters; fourisolates were found to belong to genus Streptomyces, three isolates to genus Micromonospora, one isolate to genus Nonomurea, one isolate to genus Actinomadura and one isolate could not be assigned to a genus. This work reveals that actinobacteria from the Saudi habitats have high potential anti-cancer activities and can provide a definite source for novel drugs.