Antifouling activity of crude extracts isolated from two Red Sea puffer fishes

Crude extracts were isolated from the ovary and mucus of the puffer fish Amblyrhynchotes hypselogenion and Lagocephalus sceleratus. The crude toxin extracts (from the ovaries of L. sceleratus puffer fish (4.5, 9.0, and 18.0g crude extract/100g paint) and only one concentration (3.0g crude extract/100g paint) from the skin mucus of A. hypselogenion puffer fish were mixed) with an inert simple paint formulation (consists of (vinyl chloride–vinyl acetate) copolymer using tricresyl phosphate as plasticizer. The viscosity of paints was adjusted using a blend of solvents consisting of methyl isobutyl ketone and toluene) applied to poly vinyl chloride (PVC) plates and exposed to Suez Gulf water for about 24weeks. Percentage covers of fouling organisms on plates were estimated for coated panels over six weeks, and the wet weight (gram/plate) of fouling organisms on experimental plates was recorded till about 24weeks. The percentage of plates coated by formulation with (2007 for 24weeks) the crude toxic extracts from the ovaries of L. sceleratus and the mucus of A. hypselogenion ranged from 22% to 24% and 11% to 12%, respectively. The wet weights of the plates covered by formulation with the same crude toxic extracts of the previous two species were 124–147g and 82–93g, respectively. Antifouling properties were observed for the extracts of the two species under investigation, however, extracts from A. hypselogenion showed better properties.