Discovery Of Secondary Metabolites From Marine Hydrothermal Vent Microorganisms

Marine microorganisms,especially marine fungi were proven to be a rich source of novel biologically active compounds.Marine-derived fungi residing in extreme conditions like hydrothermal vents with unique living environment.Hydrothermal vents microorganisms become the hotspot of marine natural products research since the ability of producing structurally unique secondary metabolites.In this study,three fungi strains isolated from the sample collected from Taiwan Kueishantao hydrothermal vents sediment and crabs,were cultured in normal condition.The ethyl acetate extracts of their fermentation were studied and separated by TLC,column chromatography and preparative HPLC.The structure of pure compounds were identified by NMR,HR-MS,UV,CD and Gaussion calculation.The new compounds were evaluated for antibacterial activities in vitro.From strain Penicillium sp.Y-5-2 we got 15 compounds in total.Among them 5 compounds were identified as new compounds,named as Austinone,Penicillisocoumarin A,Penicillisocoumarin B,Penicillisocoumarin C,Penicillisocoumarin D,respectively.17 compounds were isolated from strain Penicillium sp.Y-50-10 in normal culture condition.Among them 4 compounds were identified as new natural products,named as Methyl isoverrucosidinol,norpenicyrone,methyl norpenicyrone,methyl penicyrone,respectively.From strain Aspergillus versicolour XZ-4 we got 28 compounds in total.Among them 8 compounds were identified as new compounds,named as Versicomide A,Versicomide B,Versicomide C,Versicomide D,7-methoxycyclopeptin,7-methoxydehydrocyclopeptin,7-methoxycyclopenin,9-hydroxy-3-methoxyviridicatin,respectively.The proposed biosynthetic pathway of cyclopeptin derivatives were given.Because of the special habitat condition,the hydrothermal vent microorganisms grew with strong tolerance ability and adapt to heavy metals in the environment.In this study,the Penicillium sp.Y-5-2 was cultured with metal-stress,newly produced one metabolite.Isolated by preparative HPLC and identified by NMR,structure was determined to be a known compound anhydromevalonolactone.