NOTE High levels of acrylate in the Great Barrier Reef coral Acropora millepora D. M. Tapiolas • C. A. Motti • P. Holloway • S. G. Boyle Received: 28 September 2009 / Accepted: 19 February 2010 / Published online: 10 April 2010 Ó Springer-Verlag 2010 Abstract High concentrations of acrylate, 542– 683 lmol g -1 of the non-skeletal dry mass (DM), were measured in the Great Barrier Reef coral, Acropora millepora, using quantitative nuclear magnetic resonance spectroscopy (qNMR). As the amount of NaCl salt in the samples was substantial but variable, the total carbon (TC) in the coral extracts was determined, and the carbon due to acrylate found to represent 13–15% of the TC present in the total organic extracts (TOE). Acrylate, a C 3 compound, is thus a substantial carbon source in the coral holobiont and is known to be derived from dimethylsulfoniopropio- nate (DMSP), which has previously been found in corals and other organisms that harbor Symbiodinium spp. The reason for such high levels of acrylate in the corals is unknown; possible functions include antimicrobial and/or antioxidant roles, as well as playing a role in the structuring of the healthy resident coral bacteria. Keywords Acrylate Á Acrylic acid Á Acropora millepora Á qNMR Á Dimethylsulfoniopropionate Introduction Acrylate in the marine environment is thought to be derived primarily from the catabolism of the tertiary sul- fonium metabolite dimethylsulfoniopropionate (DMSP) (Cantoni and Anderson 1956), which is a critical source of carbon and sulfur in the marine food web and central to the global cycling of sulfur (Yoch 2002). DMSP is found widespread in marine organisms, including phytoplankton (Stefels 2000), macroalgae (Van Alstyne 2008), flat worms (Van Bergeijk and Stal 2001), giant clams (Hill et al. 2000), anemones (Van Alstyne et al. 2006), corals and associated coral mucus (Broadbent et al. 2002; Broadbent and Jones 2004; Van Alstyne et al. 2006) and fish (Ackman et al. 1972; Levasseur et al. 1994). DMSP in cnidarians has been attributed to their symbiotic zooxanthellae (Symbi- odinium spp), and the presence of DMSP in cultured Symbiodinium sp. (Hill et al. 1995; Broadbent et al. 2002; Coffroth et al. 2008; Van Alstyne et al. 2009) corroborates the symbiotic Symbiodinium as the source. In contrast to the numerous studies looking at DMSP in marine organisms, there are limited studies looking at biologically synthesized acrylate, its fate and possible ecological roles. The earliest reports dealt with the antibi- otic properties of acrylate in the Antarctic marine phyto- plankton Phaeocystis and in the gastrointestinal content of Antarctic penguins feeding in areas of Phaeocystis blooms (Sieburth 1960, 1961). Slezak et al. (1994) examined the potential of acrylic acid, the protonated form of acrylate, to inhibit the growth of marine bacterioplankton and showed that at concentrations present in the normal water column Communicated by Biology Editor Dr. Ruth Gates P. Holloway is on leave from Department of Biology, University of Winnipeg. Electronic supplementary material The online version of this article (doi:10.1007/s00338-010-0608-3) contains supplementary material, which is available to authorized users. D. M. Tapiolas (&) Á C. A. Motti Á S. G. Boyle Australian Institute of Marine Science, PMB No 3, Townsville MC, QLD 4810, Australia e-mail: d.tapiolas@aims.gov.au P. Holloway Department of Biology, University of Winnipeg, Manitoba R3B 2E9, Canada 123 Coral Reefs (2010) 29:621–625 DOI 10.1007/s00338-010-0608-3