Terpenoids from Kiwi endophytic fungus Bipolaris sp. and their antibacterial activity against Pseudomonas syringae pv. actinidiae

Abstract

A chemical investigation on the kiwi endophytic fungus Bipolaris sp. Resulted in the isolation of eight new terpenoids ( 1 – 8 ) and five known analogues ( 9 – 13 ). Compounds 1 – 5 are novel sativene sesquiterpenoids containing three additional skeletal carbons, while compounds 4 and 5 are rare dimers. Compounds 6 – 8 and 13 are sesterterpenoids that have been identified from this species for the first time. Compounds 4 and 5 showed antibacterial activity against kiwifruit canker pathogen Pseudomonas syringae pv. Actinidiae (Psa) with MIC values of 32 and 64 μ g/ml, respectively.