The antifungal metabolites obtained from the rhizospheric Aspergillus sp. YIM PH30001 against pathogenic fungi of Panax notoginseng

Abstract

Eight anthraquinones (1–8), three xanthones (11–13) and two phenols (9–10) were isolated from Aspergillus sp. associated with Panax notoginseng, and their structures were determined as ziganein-1-methyl ether (1), 8-O-methylchrysophanol (2), averythrin (3), averufin (4), 8-O-methyl averufin (5), versicolorin B (6), averantin (7), methyl-averantin (8), arugosin C (9), diorcinol (10), sterigmatocystin (11), demethylsterigmatocystin (12) and dihydrosterigmatocystin (13) by spectroscopic analyses. Compounds 1, 2 and 5 were the novel isolates from genus Aspergillus. Compounds 3, 6 and 7 exhibited antifungal activity against Fusariumsolani, pathogenic fungus of P. notoginseng, with minimum inhibitory concentrations (MICs) of 16–32 μg/mL, and compounds 1, 3, 4, 7 and 9 showed antibacterial activity against Bacillussubtilis with MICs of 64–128 μg/mL, 16–32 μg/mL, 8–16 μg/mL, 16–32 μg/mL and 64–128 μg/mL, respectively. The metabolites showed the potential value in the research of antifungal agents, especially in searching for a biocontrol of diseases of P. notoginseng. The preliminary structure–activity relationships have been discussed for some of the compounds.

Keywords::

• Aspergillus sp
• anthraquinones
• xanthones
• antifungal activities

Acknowledgements

This project was supported by the National Natural Science Foundation of China (81360480, U0932601, 41361075) and Educational Commission of Yunnan Province (ZD2013008).