Identification and Dereplication of Lipopeptides from Cyanobacteria

Cyanobacteria have been a focus of research as a prominent producer of secondary metabolites which possess unique activities and structural components. In this thesis, we showcase the value of dereplication strategies using untargeted MS/MS, GNPS molecular networking, NMR spectroscopy, and bioassay guided fractionation to identify known and novel natural products from cyanobacterial cultures UIC 10885 and UIC 10832. Within this paper we report the isolation and identification of a series of Hassallidin C and D analogues from UIC 10885, which were isolated by semi-preparative HPLC and analyzed using MS/MS and H1 NMR methods. The third chapter of this thesis is dedicated to the preliminary identification of a potential novel lipopeptide from UIC 10832, which was isolated using the same methods listed above. All compounds were screened against cancer cell lines in order to identify anti-proliferative properties.