Chemical Components of Hirsutella thompsonii Crude Filtrate and their Biological Activities

Abstract

Hirsutella thompsonii # 966 was cultured and extracted with ethyl acetate. The ethyl acetate layer was then eluted on Sephadex LH-20 column with methanol and the eluted chemical components were analyzed on a Bruker DRX 400 NMR spectrophotometer. The analysis showed several components such as glycerol, ergosterol and diketopiperazine. This was the first time that diketopiperazine had been isolated from H. thompsonii and it was known that diketopiperazine compounds had certain biological activities. Hirsutellide A was not present in the crude extract. The freeze-dried broth and the residue from evaporation of the broth (crude solvent extract) were dissolved in dimethyl sulfoxide (DMSO) in order to test for their cytotoxicity against insect and mammalian cell lines. A bioassay revealed that the crude broth sample was weakly toxic and the crude solvent extract was non-toxic to all cell lines tested in the range of 0.78-100 mg/ml. The crude solvent extract had tendency to stimulate cell activity, especially in mammalian cell line (BHK(21)C13.