Secondary metabolites of Eurotium cristatum from Fu Brick Tea and their biological activities / 中草药

ABSTRACT

Objective: To study the secondary metabolites of Eurotium cristatum from Fu Brick Tea and their biological activities. Methods: The compounds were isolated by various column chromatographies on normal phase silica gel, reversed silica gel, Sephadex LH-20, preparative TLC, and recrystallization. The structures were identified by the extensive analysis on their spectroscopic data. The inhibitory effects of compounds 1-9 against SF-268, MCF-7, and NCI-H460 cell lines were tested in vitro by SRB method. The inhibitory effects of compounds 2-9 on Staphyloccocus aureus, Escherichia coli, Salmonella enterica subsp. enterica, Shigella dysenteriae, and Proteus vulgaris were tested by MTT method. Results: Nine compounds were isolated from the extract of liquid fermentation broth of E. cristatum in Fu Brick Tea and identified as physcion (1), 1, 5-dihydroxy-3-methoxy-7-methyl-anthracene-9,10-dione (2), flavoglaucin (3), 2-(2', 3-epoxy-1', 3'-heptadienyl)-6-hydroxy-5-(3-methyl-2-butenyl) benzaldehyde (4), 2-(2', 3-epoxy-1', 3', 5'-heptatrienyl)-6-hydroxy-5-(3-methyl-2-butenyl) benzaldehyde (5), isodihydroauroglaucin (6), tyrosol (7), p-hydroxybenzoic acid (8), and orcinol (9). The results of the bioactivity test showed that compounds 3-6 displayed the good cytotoxic acitivities against the three tumor cell lines, and all the compounds exhibited the strong inhibitory activities against P. vulgaris except compounds 1 and 6. Besides, compound 9 also showed the significant inhibitory effects against S. aureus and E. coli. Conclusion: The benzaldehyde compounds are considered as the main metabolites of E. cristatum, compounds 7 and 9 are reported from the species of genus Eurotium Link Fr. for the first time and compounds 2, 3, 5, 6, and 8 are firstly isolated from the fungus.