Eight micropeptins from a Microcystis spp. bloom collected from a fishpond near Kibbutz Lehavot HaBashan, Israel

Eight new micropeptin-type cyclic depsipeptides, micropeptins LH920, LH1021, LH1048, LH1062, LH911A, LH911B, LH911C, and LH925, along with five known micropeptins, three known anabaenopeptins and two known microcystins (LR and RR), were isolated from a water bloom biomass of Microcystis spp. assembly that was collected from a fishpond near Kibbutz Lehavot HaBashan, Israel. The structures of the pure compounds were elucidated using 1D and 2D NMR techniques, as well as high-resolution mass spectrometry. The stereochemistry of the new natural products was determined using Marfeyʹs method for amino acids. The inhibitory activity of the compounds was determined for the serine proteases, trypsin, and chymotrypsin.