Antimicrobial, Antiprotozoal, and Toxic Activities of Cnidarian Extracts from the Mexican Caribbean Sea

Abstract

Antimicrobial, antiprotozoal, and toxic activities of crude extracts obtained from six cnidarian species [Cassiopea xamachana. (R.R. Bigelow, 1892), Carybdea marsupialis. (Linné, 1758), Linuche unguiculata. (Swartz, 1788), Bartholomea annulata. (Leseur, 1817), Lebrunia danae. (Duchassaing and Michelotti, 1860), and Stichodactyla helianthus. (Ellis, 1768)] from the Mexican Caribbean Sea were studied. The extract obtained from Linuche unguiculata. was found to be the most active against the yeast Candida albicans. and the protozoan Giardia lamblia. with 24 mm of inhibition zone diameter and an IC50 of 63.2 µg mL−1, respectively. Additionally, in an effort to assess the effects caused by the treatment of cnidarian's toxins in vertebrates, we used tilapias (Oreochromis niloticus.) as a laboratory model. The results showed that only 44 mg kg−1 of jellyfish (Carybdea marsupialis.) toxin were necessary to cause significant mortality in fish. Tilapias treated with the Stichodactyla. toxin demonstrated hemolytic damage and cellular abnormalities.