THE CHARACTERIZATION OF ARSENOSUGARS IN COMMERCIALLY AVAILABLE ALGAL PRODUCTS INCLUDING A NOSTOC SPECIES OF TERRESTRIAL ORIGIN

The arsenic species present in a range of commercially available dried -algal food products were characterized by HPLC-ICP-MS, The products o f marine origin contain up to four dimethylarsinylribosides (1) in the 8-49 ppm range and some also contain dimethylarsinic acid (DMAA). The se species are easily extracted and account for most of the arsenic bu rden. One sample of a freshwater alga Nostoc sp, was found to contain a lower concentration of arsenic, 3 ppm, and only 34% of this was extr actable, The extract representing 1 ppm of arsenic contained one of th e arsenosugars 1 found in the marine samples (93%), the rest being DMA A, This is the first report of the identification of an arsenosugar fr om an organism of terrestrial origin, The implications of this result in connection with the global arsenic cycle are discussed. (C) 1997 Jo hn Wiley & Sons, Ltd.