Novel cyanobacterial metabolites, cyanopeptolin 1081 and anabaenopeptin 899, isolated from an enrichment culture dominated byWoronichinia naegeliana(Unger) Elenkin

Cyanobacteria synthesize many secondary metabolites of various chemical structures and biological activity and release them into the aquatic environment. Two new oligopeptides belonging to anabaenopeptins and cyanopeptolins were isolated from an enrichment culture dominated byWoronichinia naegeliana(Unger) Elenkin. The application of mass spectrometry and nuclear magnetic resonance spectroscopy allowed determination of their structure and identification of these compounds as cyanopeptolin 1081 and anabaenopeptin 899 with a molecular formula C(52)H(75)N(9)O(16)and C48H65N7O10, respectively. The preliminary evaluation of their toxicity was conducted via tests based on crustaceanThamnocephalus platyurus. Although these peptides did not exert acute toxic effects at the concentration up to 40 mu g ml(-1), deterioration of the physiological state of the studied crustaceans, indicated by reduced mobility, was observed. Considering the limited knowledge of cyanopeptide presence in the aquatic environment, it is important to identify and characterize these compounds.

Automated summary

Cyanobacteria produce various secondary metabolites, including two new oligopeptides identified in this study. While these peptides did not show acute toxic effects on crustaceans at high concentrations, they led to a deterioration of physiological state. Identifying and characterizing cyanopeptides in aquatic environments is crucial due to limited knowledge in this area.