Field experimental evaluation of secondary metabolites from marine invertebrates as antifoulants

Abstract

The crude organic extracts of the endemic gorgonian Phyllogorgia dilatata and two sponge species Aplysina fulva and Mycale microsigmatosa were evaluated for anti-fouling properties through field experiments. To investigate this property in ecologically meaningful conditions, crude extracts from these invertebrates were incorporated at concentrations naturally found in these marine organisms into a stable gel used as a substratum for fouling settlement. Crude extract from A. fulva showed no significant anti-fouling property at the natural concentrations used in the field experiments. In fact, fouling organisms settled significantly more on gels treated with A. fulva extract than on the control gel. On the other hand, both M. microsigmatosa and P. dilatata yielded crude extracts that exhibited a selective action inhibiting only the settlement of barnacles. The evidences obtained here by means of field experiments can provide a basis for future development of one kind of natural antifoulant technology to prevent marine biofouling.Key words: marine invertebrates, anti-fouling, secondary metabolites. RESUMO Avaliação experimental de metabólitos secundários de invertebrados marinhos como antiincrustantes em campoAs propriedades antiincrustantes dos extratos brutos da gorgônia endêmica Phyllogorgia dilatata e de duas espécies de esponja, Aplysina fulva e Mycale microsigmatosa, foram avaliadas por intermédio de ensaios de campo. Para investigar essas propriedades sob condições ecologicamente relevantes, as concentrações naturais dos extratos brutos encontrados nesses invertebrados foram incorporadas a um gel estável que serviu de substrato para o assentamento de organismos incrustantes. O extrato bruto de A. fulva não mostrou efeito antiincrustante na concentração natural usada nos experimentos. De fato, os organismos incrustantes colonizaram significativamente mais o gel contendo extrato de A. fulva do que o gel-controle. Por outro lado, ambos os invertebrados, M. microsigmatosa e P. dilatata, produzem extratos brutos que foram seletivamente ativos contra o estabelecimento de balanídeos. As evidências obtidas aqui, por meio de experimentos em campo, podem ser importantes subsídios para futuras investigações visando à aplicação industrial de produtos naturais antiincrustantes em tecnologias de prevenção da bioincrustação marinha.Palavras-chave: invertebrados marinhos, antiincrustação, metabólitos secundários.

Exploitation of marine algae: biogenic compounds for potential antifouling applications

“…There have been numerous studies, across the globe, reporting the bioactivities of marine-sourced organisms (e.g. Tziveleka et al 2003;Peters et al 2003;Yim et al 2004;Iken and Baker 2003;Tsoukatou et al 2002;Bhosale et al 2002;de Nys and Steinberg 2002;Pereira et al 2002;Wilsanand et al 2001;Armstrong et al 2000;Abarzua et al 1999;Ko¨nig et al 1999a;Siddhanta et al 1997;Badria et al 1997;Bernan et al 1997;Carte 1996;Sato 1996;Dhawan et al 1993;Sridhar and Vidyavathi 1991). Biogenic compounds belonging to several classes of marine micro-and macro-algae have been identified over the last few decades, and their chemical constitution and pharmacological activity have been studied in detail (e.g.…”

Epibenthic colonization on an artificial reef in a stressed environment off the north coast of the Rio de Janeiro State, Brazil

“…The highest negative correlations among the dominant taxa were between Balanus and Ostrea (-0.44), Ostrea and Obelia (-0.51), Bougainvillia and Obelia (-0.55), Balanus and Bougainvillia (-0.65). Chemical inhibitions among epibenthic species frequently occur in submerged substrates (Engel and Pawlik, 2000;Pereira et al, 2002;Pisut and Pawlik, 2002). Concerning the interactions among the recruits and the residents, facilitation interaction was mainly observed (sensu Connell and Slatyer, 1977) among organisms of the same taxonomic category.…”

Antifouling activity of twelve demosponges from Brazil

“…The antifouling property of marine benthic invertebrates from the Brazilian coast are still poorly known; to this date, only a single species of gorgonian, Phyllogorgia dilatata (Esper) and three of sponges were investigated: Geodia corticostylifera Hajdu et al, Mycale microsigmatosa Arndt and Aplysina fulva (Pallas). The extract of G. corticostylifera had strong antifouling activity, preventing the establishment of the bivalve Perna perna in laboratorial tests (Clavico et al, 2006), while extracts of M. microsigmatosa and P. dilatata selectively inhibited the establishment of barnacles and A. fulva did not showed antifouling effects in field experiments (Pereira et al, 2002). As there are more than 300 species of marine sponges in the Brazilian coast, this area of knowledge is clearly little explored in Brazil and there is great potential for the discovery of new antifouling compounds.…”