A unique arsenic profile with unusual arsenic compounds discovered in the edible mushroom Sparassis crispa

The edible and medicinal mushroom Sparassis crispa contains a diverse profile of arsenic species. We investigated the arsenic profile of extracts from four different fruiting bodies of S. crispa originating from Austria and Czechia. Besides the previously known arsenic species arsenocholine, trimethylarsine oxide, trimethyl(2-carboxyethyl)arsonium, arsenobetaine amide, and the tetramethylarsonium ion, we were able to identify the uncommon α-glycerophosphorylarsenocholine-previously only identified as a minor arsenic species in marine animals-as a major arsenic species. Furthermore, a novel arsenic compound, i.e., β-methyl arsenocholine, was identified as a naturally occurring compound in all investigated samples of S. crispa. We present methods for the preparation of synthetic α-glycerophosphorylarsenocholine and β-methyl arsenocholine, which were used to confirm their presence in S. crispa.