Browse by author
Lookup NU author(s): Dr Gary Caldwell,
Dr Rebecca Taylor,
Emeritus Professor Peter Olive,
Emeritus Professor Matt Bentley
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Diatoms have traditionally been regarded as the ‘grass of the sea’, essentially an inert parcel of nutrients in a silica casing. Research within the last decade has begun to challenge this view. It has come to light that diatoms possess a sophisticated chemical defence strategy that revolves around the production of reactive chemical species following lipid peroxidation. The production of defensive chemicals is initiated following mechanical damage to the diatom frustule and cell membranes. The bioactive molecules produced include unsaturated shortchain aldehydes and oxo-acids. These toxins specifically target invertebrate reproductive processes including the oocyte fertilization current, sperm motility and embryonic mitosis. The aldehydes are highly cytotoxic and induce apoptosis and necrosis in exposed cells, embryos and larvae. We have extracted the toxic aldehyde decadienal from the planktonic diatom Skeletonema costatum and the benthic diatom Nitzschia commutata. We have also investigated the toxicity of diatom-derived aldehydes to benthic marine macroinvertebrates. The polychaete worms Nereis virens and Arenicola marina exhibit extreme sensitivity to decadienal compared with echinoderm, crustacean and ascidian comparators. We suggest that the aldehydes are functioning as endocrine disrupters in these polychaetes. We argue that diatom toxicity represents a strong selective pressure in benthic systems for the evolution of seasonal spawning strategies. We will also discuss the possible impacts of diatom aldehydes to the aquaculture industry either from the application of diatoms as larval feeds or from direct environmental exposure.
Author(s): Caldwell GS, Taylor RL, Olive PJW, Bentley MG
Publication type: Article
Publication status: Published
Journal: Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology
Pages: S35 abstract no. A5.2
ISSN (print): 1095-6433
ISSN (electronic): 1531-4332
Publisher: Elsevier Inc.
Altmetrics provided by Altmetric