Abstract: 14 metabolites,namely ergosterol (1), ergosta-4,6,8,22-tetraen-3-one (2), cerevisterol (3), 9(11)-dehyoergosterol peroxide (4), alternariol (5), physcion (6 ), Indole-3-carboxylic acid (7), 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran (8), anthranilamide (9), anthranilic acid (10), 3-methylorsellinic acid (11), mannitol (12), chaetoglobosin A (13) and 5′-epichaetovirdin A (14) were firstly isolated from the extract of fermentation broth of fungus Chaetomium sp.RSQMK-9, an endophyte of Panax ginseng. Their chemical structures were elucidated by spectroscopic methods,compound 6 was firstly isolated from the genus Chaetomium. The toxicities of compounds 13 and 14 were tested by brine shrimp bioassay,and the mortality rates of compound 13 and 14 against Artemia salina larvae were 83.4% and 54.3%,respectively,at the concentration of 10 μg/mL.

Key words: Panax ginseng, endophytic fungus, Chaetomium sp., chemical constituents, Artemia salina, toxicity