MS-guided Fractionation as a Fast Way to the Identification of New Natural Products – MALDI-TOF-MS Screening of the Marine Sponge Stylissa caribica

Abstract

MALDI-TOF-MS was used for the first time as a direct screening method to analyse sponge tissue (Stylissa caribica). In order to validate this method the results were compared with a HPLC-ESI-MS analysis of the crude extract from the investigated sponge. Both methods showed a good agreement in their results, allowing for the rapid identification of 15 pyrrole-imidazole alkaloids.

New Tricks with an Old Sponge: Feature-Based Molecular Networking Led to Fast Identification of New Stylissamide L from Stylissa caribica

“…Twenty different brominated pyrrole-imidazole alkaloids have been detected in S. caribica so far, and nine of them have been reported for the first time from this sponge, including N-methyldibromoisophakellin, oxocyclostylidol, 4-bromopyrrole-2-carboxy- N (ε)-lysine, and 4-bromopyrrole-2-carboxyarginine. In addition, 13 cyclic heptapeptides have been found in S. caribica [ 17 , 18 , 19 , 20 , 21 ], and ten of them were new compounds at the time of the report ( Table S1 ). Among them, it is worth mentioning stylissamide G and H, which exhibited cytotoxic activity towards HCT-116, human colon tumor cell line [ 21 ].…”