Antifoulant property of the marine sponge Hymeniacidon heliophila (Demospongiae: Halichondrida)

Abstract

Universidade Federal de Santa Catarina Centro de Ciencias da Saude, Pos-graduacao em Farmacia - Laboratorio de Produtos Naturais (Campus Universitario da Trindade, 88.040-970 Florianopolis, SC, Brasil) *Corresponding author e-mail: suzimr@yahoo.com.br Marine sponges (Porifera) produce a plethora of different chemicals with important biological and ecological roles, such as antipredatory (PAWLIK et al., 1995), antioxidant (LYSEK et al., 2003), allelopathic (ENGEL; PAWLIK, 2000; PAWLIK et al., 2007; CHAVES-FONNEGRA et al., 2008), antimicrobial (THOMPSON et al., 1985; YALCIN, 2007), and antifoulant (HENRIKSON; PAWLIK, 1998; CHAVES-FONNEGRA et al., 2005), among others. Hymeniacidon heliophila is a marine sponge found throughout the Atlantic ocean (GINN et al., 1998; LERNER et al., 2005). This species is distributed along the coast of the State of Rio de Janeiro, living in various habitats including some highly polluted ones, such as Guanabara Bay, into which large quantities of untreated sewage have been discharged since the 1950s (BREVES-RAMOS et al., 2005; BORGES et al., 2009). Several compounds have already been reported for the genus Hymeniacidon , such as peptides, alkaloids, lipids and steroids (INABA et al., 1998; GRANATO et al., 2000; NECHEV et al., 2004; BLUNT et al., 2009), but little is known about their ecological roles. Previous studies have shown that L-5-hydroxytryptophan isolated from H. heliophila acts as a protection against UV radiation (LYSEK et al., 2003). Crude extract obtained from H. heliophila collected in North Carolina (U.S.A.) were assayed as antifoulants in a field experiment, however, no activity wasdetected (HENRIKSON; PAWLIK 1998). Recently, some crude extracts from H. heliophila collected on the Brazilian coast were recorded as active defense against predation by sea urchins, hermit crabs and fishes (RIBEIRO et al., 2010). Based on previous knowledge of the multiple functionality of secondary metabolites from marine organisms, this study reports on the antifouling property of three crude extracts of H. heliophila with distinct polarities acting against the byssal attachment of the mussel Perna perna (Linnaeus) (Bivalvia, Mytillidae) (PAUL, 1992; SCHMITT et al., 1995; MCCLINTOCK et al., 2001). This note is the first record of antifoulants from H. heliophila in the South Atlantic. Sponges and mussels were collected by free diving and by hand on Itaipu beach, Niteroi city (Rio de Janeiro State, 22o58’19’’S – 43o02’44’’W) in July 2005 and freeze-dried to yield 75 g of dry-mass, which was extracted with n-hexane, ethyl acetate and acetone/methanol (1:1), furnishing three extracts named HE, EA and AM, respectively. Laboratory experiments were performed following the method detailed by Da Gama et al. (2003). For each of ten replicates utilized we used two overlapped filter papers (treatment and control) in a Petri dish of 9 cm diameter. Treatment filters were cut in a chessboard pattern (1.5 cm-side squares) and placed above the control filters which were used whole, without any cut chessboard pattern. Treatment filters were soaked in crude extract diluted in dichloromethane (CH