A new di-O-prenylated flavone from an actinomycete Streptomyces sp. MA-12

Abstract

A new di-O-prenylated flavone, named 7,3′-di-(γ,γ-dimethylallyloxy)-5-hydroxy-4′-methoxyflavone (1), was isolated from the culture broth of the endophytic actinomycete Streptomyces sp. MA-12 isolated from the root of the semi-mangrove plant Myoporum bontioides A. Gray. The structure of 1 was determined by comprehensive spectroscopic methods, including 1D and 2D NMR experiments (COSY, HMQC, and HMBC). Primary bioassays showed that 1 at concentration of 0.25 mM had moderate inhibitory activity against three plant pathogenic fungi including Colletotrichum musae, Gibberella zeae (Schweinitz) Petch, and Penicillium citrinum Thom.

Keywords:

• mangrove actinomycete
• flavone
• antifungal
• Streptomyces sp.

Acknowledgements

We wish to acknowledge financial supports by the National Natural Science Foundation of China (21102049), the Natural Science Foundation of Guangdong Province (9451064201003751), the Science and Technology Project of Guangzhou City (11C12100771), the Key Academic Program of the 3rd Phase ‘211 Project’ of South China Agricultural University (2009B010100001), the 2011 Foundation for High-level Talents in Higher Education of Guangdong Province (awarded to Xiu-Fang Wang of Guangdong Pharmaceutical University. Wei-jia Ding is one of the project personnels), and the 2012 Innovation Experiment Program for University students (awarded to Sui-Qiang Zhang, Yue-Xia Lin, Qiao-Xia Liang, and Wei-Jian Zhao) of South China Agricultural University (SCX12097).