Homoarsenocholine – A novel arsenic compound detected for the first time in nature

The arsenic speciation was determined in macrofungi of the Ramaria genus with HPLC coupled to inductively coupled plasma mass spectrometry. Besides arsenic species that are already known for macrofungi, like arsenobetaine or arsenocholine, two compounds that were only known from marine samples so far (trimethylarsoniopropanate and dimethylarsinoylacetate) were found for the first time in a terrestrial sample. An unknown arsenical was isolated and identified as homoarsenocholine. This could be a key intermediate for further elucidation of the biotransformation mechanisms of arsenic. [Display omitted] •First identification of homoarsenocholine in nature.•First report of trimethylarsoniopropanate and dimethylarsinoylacetate in fungi.•First comprehensive arsenic speciation analysis of Ramaria macrofungi.