Rosalva Defreece

A diffusion chamber for assessing efficacy of natural anti-fouling defenses in marine organisms [An article from: Journal of Experimental Marine Biology and Ecology] : This digital document is a journal article from Journal of Experimental Marine Biology and Ecology, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
A slow-release diffusion chamber is here described for use in assessing the effectiveness of potentially bioactive compounds as anti-fouling agents. Its settlement surface is a porous 15 mm thick slab of Portites lobata skeleton, through which an aqueous extract of a given marine organism is permitted to diffuse. The chamber is placed at an underwater site for 30 days at a time, and settlement of sessile, benthic organisms, particularly algae, is permitted to occur. Comparative settlement levels were compared between chambers containing an extract and a seawater control. An extract of Sinularia flexibilis (Octocorallia, Alcyonacea) was assessed using such chambers and found to be an effective natural anti-fouling agent or defense mechanism against Ectocarpus sp. and pennate diatoms, reducing their cover by ~ 50% when compared to experimental conditions using seawater as a control. Intra-chamber variability in extract concentration was found to be minimal. No significant differences were found in extract concentrations between replicate chambers through time. The chamber is a highly cost-effective and efficient tool by which such assessments can be made and easily replicated. It is recommended that coral which has recently died be collected and used as a source of substratum for this purpose.
A diffusion chamber for assessing efficacy of natural anti-fouling defenses in marine organisms [An article from: Journal of Experimental Marine Biology and Ecology]