Antimicrobial activity in the tissue extracts of five species of cowries <i>Cypraea</i> spp. (Mollusca: Gastropoda) and an ascidian <i style="">Didemnum psammathodes </i>(Tunicata: Didemnidae)

Abstract

Five species of Cypraea (<i style="">Cypraea errones, C. arabica, C. onyx, C. tigris</i> and <i style="">C. vitellus</i>) were assayed for their antibacterial and antifungal activity against 15 bacterial pathogens and 3 fungal pathogens. Antibacterial and antifungal activities were exhibited only by <i style="">C. errones</i> extracts. An ascidian, <i style="">Didemnum psammathodes</i>, the principal diet of <i style="">C. errones</i> was also assayed for antimicrobial activity to evaluate whether the activity exhibited by <i style="">C. errones</i> was derived from its diet. The ascidian extract exhibited broad-spectrum antibacterial activity. Chromatographic fractionation of the extracts of <i style="">C. errones</i> and <i style="">Didemnum psammathodes </i>confirmed that the activity exhibited by <i style="">C. errones</i> was not diet derived.