Arsenosugar

Arsenosugars, also known as arsenic-containing ribofuranosides, are a class of organoarsenic compound and ribose derivative predominantly found in algae, seaweed and marine animals.¹

There are several types of arsenosugar with the main ones being: oxo-, where an oxygen is double bonded to the arsenic; thio-, where a sulfur double bonds to the arsenic; and methyl-arsenosugars, where the arsenic atom is bonded to 2 or 3 methyl groups. The R-group represents an organic group with common groups including glycerol, sulfate, sulfonate and phosphate. There are a total of over 70 types of arsenosugars with a known structure.²

Arsenosugars were first isolated and identified in 1981 from Ecklonia radiata and are found predominantly in marine organisms.³ Arsenosugars are produced by some algae and bacteria, such as Synechocystis and Chlorella vulgaris⁴ which can convert inorganic arsenic, such as arsenite ions, into various organo-arsenic compounds including methlyarsenous acid and dimethylarsinous acid which then get converted to arsenosugars. These arsenosugars may then further be converted into arsenolipids.³

Compared to many other organo-arsenic compounds, but similar to arsenobetaine, arsenosugars are generally non-toxic and pose less of a health concern to humans.⁵ However, some possible products of metabolism can be toxic, however, little research has been performed into their exact toxicities.⁶