Development of a High-Resolution Tandem Mass Spectral Library for Pyrrolizidine Alkaloids (PASL)

This Data Descriptor reports the submission of a High-Resolution Orbitrap Mass Spectral Library of Pyrrolizidine Alkaloids (PASL) to public repositories. The library contains 165 tandem mass spectra (MS/MS) from 84 pyrrolizidine alkaloid (PA) standards, along with 18 additional PAs manually annotated in crude plant extracts. This collection comprises most commercially available PAs and a unique selection of annotated (in crude extracts) and synthesized compounds. The PASL serves as a valuable resource for identifying PAs in complex mixtures without analytical standards and facilitates the annotation of novel PAs through molecular networking approach. To ensure high quality, the library was validated by dereplicating its spectra against the GNPS libraries and applying it to the annotation of two PA-producing plant species. The spectra of the PASL can be accessed through GNPS ( https://gnps.ucsd.edu/ProteoSAFe/gnpslibrary.jsp?library=PYRROLIZIDINE-ALKALOID-SPECTRAL-LIBRARY ), with accession numbers ranging from CCMSLIB00014205782 to CCMSLIB00014205946 . The PASL in .mgf format can be downloaded from GNPS under: https://external.gnps2.org/gnpslibrary . The PASL enables rapid and straightforward annotation of both known and novel PAs, accelerating research in food safety and related fields.