[Culture conditions and analysis of amanitins on Amanita spissa].

Isolate of Amanita spissa was obtained from basidiome stipe material collected from environment. It could utilize a broad range of carbon and nitrogen resources. Study on the influence of different conditions for solid culture was carried out. Optimal culture conditions were at 28 degrees C, pH6, in the dark. A. spissa was then fermentated in liquid culture for more mycelia. In flask and Airlift/ff bioreactor, maximum dry mycelia weight of A. spissa reached 0.893 g/L and 2.33 g/L, respectively. Mycelia obtained from solid culture and Airlift/ff bioreactor were then analyzed by HPLC. The results showed that mycelia from both cultures contained amatoxins but no phallotoxins. alpha-Amanitin in mycelia reached 26.02 microg/DWg under solid culture condition, and 15.25 microg/DWg under liquid culture condition. The amanitins were also confirmed by bud-inhibited assay. The results revealed that the effect of amanitin on mung bean cell was identical to that of authentic amanitins. This work suggests that it is possible to produce amatoxin by liquid culturing of A. spissa.