MEPS 325:137-144 (2006)  -  doi:10.3354/meps325137

‘Chlorophyll-like’ compounds as novel biomarkers of stress in corals

K. E. McDougall1,*, S. W. Gibb1, K. G. Boyd1, B. E. Brown1,2

1Environmental Research Institute, North Highland College, UHI Millennium Institute, Castle Street, Thurso, Caithness KW14 7JD, UK
2School of Biology, University of Newcastle, Newcastle upon Tyne NE1 7RU, UK

ABSTRACT: The appearance of ‘bleached’ or pale-coloured corals at numerous locations around the world over the last 3 decades has been linked to various environmental stressors. However, the role and fate of zooxanthellar pigments in response to such stress has received little attention. We provide new insights into the adaptive response of coral zooxanthellae to environmental stress, based upon the analysis of chlorophyll pigments using high performance liquid chromatography. Manipulative field experiments were used to monitor induction and recovery of the reef coral Goniastrea aspera from photo-damage. Over a 6 d period the production of up to 6 compounds with very similar light absorbance spectra to chlorophyll a (chl a) was observed. Higher concentrations of a sub-set of these products were observed in response to elevated solar radiation levels. The fact that the same chl a-like compounds were consistently observed under the same experimental conditions means that they may have significant potential as biomarkers of stress in corals and may also provide a means of ‘fingerprinting’ environmental stress in corals.

KEY WORDS: Coral bleaching · Stress biomarkers · Symbiotic algae · Chlorophyll a · HPLC

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