Objective: To study on gliotoxin metabolites from endophytic Penicillium sp. of Astragali Radix and investigate their antimicrobial activity to Erysiphe pisi. Method: The compounds were isolated and purified by repeated silica gel column chromatography

Sephadex LH-20 gel chromatography

and HPLC method; their chemical structures were identified by chemical methods combined with nuclear magnetic resonance analysis and mass spectrometry. The MIC values for E. pisi. were determined as sensitivity to the compounds in biological evaluation. Result: Seven gliotoxins were obtained and elucidated as gliotoxin (1)

bisdethiobis(methylthio) gliotoxin (2)

dehydroxybisdethiobis(methylthio) gliotoxin (3)

dehydrogliotoxin (4)

6-deoxy-5a

6-didehydrogliotoxin (5)

didehydrobisdethiobis (methylthio) gliotoxin (6)

and bis-N-norgliovietin (7). Bacteriostasic activity test results showed that compounds 1

4 and 5 had strong inhibitory activity for E. pisi

MIC values of 1.56

0.78 and 6.25 mg·L-1. Conclusion: All compounds were isolated from the endophytic fungi of Astragali Radix for the first time

and the endophytic fungus Aspergillus sp. from the stems of Astragali Radix

is a promising source for gliotoxins.