Marine Biotechnology

Biofilms

Electronic Journal of Biotechnology ISSN: 0717-3458 Vol. 10 No. 1, Issue of January 15, 2007
© 2007 by Pontificia Universidad Católica de Valparaíso -- Chile Received November 7, 2005 / Accepted July 27, 2006
DOI: 10.2225/vol10-issue1-fulltext-6  
RESEARCH ARTICLE

The inhibitory effect of biofilms produced by wild bacterial isolates to the larval settlement of the fouling ascidia Ciona intestinalis and Pyura praeputialis

Manuel Zapata
Laboratorio de Ecología Microbiana
Departamento de Acuicultura
Facultad de Recursos del Mar
Universidad de Antofagasta
Av. Jaime Guzmán s/n Casilla 170
Antofagasta, Chile
Tel: 56 55 637881
Fax: 56 55 637804
E-mail: mzarcos@gmail.com 

Fernando Silva
Laboratorio de Ecología Microbiana
Departamento de Acuicultura
Facultad de Recursos del Mar
Universidad de Antofagasta
Av. Jaime Guzmán s/n Casilla 170
Antofagasta, Chile
Tel: 56 55 637881
Fax: 56 55 637804
E-mail: fsaciares@gmail.com 

Yery Luza
Laboratorio de Ecología Microbiana
Departamento de Acuicultura
Facultad de Recursos del Mar
Universidad de Antofagasta
Av. Jaime Guzmán s/n Casilla 170
Antofagasta, Chile
Tel: 56 55 637881
Fax: 56 55 637804
E-mail: yerynaram@gmail.com 

Marcela Wilkens
Laboratorio de Microbiología Molecular
Departamento de Biología
Universidad de Santiago
Av Lib Bernardo O'Higgins 3363
Estación Central, Santiago, Chile
Tel: 56 55 637881
Fax: 56 55 637804
E-mail: mwilkens@lauca.usach.cl 

Carlos Riquelme*
Laboratorio de Ecología Microbiana
Departamento de Acuicultura
Facultad de Recursos del Mar
Universidad de Antofagasta
Av. Jaime Guzmán s/n Casilla 170
Antofagasta, Chile
Tel: 56 55 637881
Fax: 56 55 637804
E-mail: ceriquelme@gmail.com

*Corresponding author

Financial support: Chilean National Fund for Promotion of Scientific and Technological Development (FONDEF) project Nº DO1I1166. 

Keywords: antifouling extracts, ascidian bioassays, bacterial biofilms, Ciona intestinalis, marine biofouling, natural antifoulants, Pyura praeputialis.

Abbreviations:

EP: extracellular products
HPLC: high pressure liquid chromatrography
MMM: marine minimal medium
TBT: tributyl-tin

Abstract
Full Text

Marine biofouling is a present and potentially increasing future problem at molluscan culture centres. The problem is highly variable, exists on different scales, and its negative impact on cultured organisms and related economic losses at these centres has not been significantly controlled. One approach to fouling control has been the incorporation of natural substances into anti-fouling paints which inhibit the settlement of common fouling organisms. The main objective of the present study was the isolation of naturally occurring substances from marine bacteria which were inhibitory to the settlement of Ciona intestinalis and Pyura praeputialis, two tunicate species causing serious fouling problems in scallop culture systems in Chile. Numerous bacterial strains were isolated from microfouling on natural and artificial substrates submerged in the sea; of 73 strains isolated, 20% demonstrated inhibitory effects on the settlement of the larvae of the above cited tunicates. The inhibitory substances produced by the active bacteria were extracellular, and could be incorporated in an inert matrix (PhytagelTM) without losing their inhibitory properties. Some properties of the inhibitory substance isolated from bacterial strain Clon Nil-LEM (Alteromonas sp) included thermostability, MW < 3500 Da, peptidase lability (against C. intestinalis), and undiminished inhibitory activity when incorporated in the inert matrix.

Supported by UNESCO / MIRCEN network