Isolation and identification of toxins inhibiting Dentrolimus tabulaeformis from an antagonistic strain of Beauveria

Abstract:

[Objective] We used submerged fermentation to cultivate a strain of the entomopathogenic fungus Beauveria tenella isolated from the infected larvae of Dentrolimus tabulaeformis in Pinus tabulaeformis forest in Chengde of Hebei Province in China [Methods] We used ethyl acetate to extract antagonistic components from the fermentation broth and used silica gel column chromatography and GC/MS to separate and identify the components. [Results] Six compounds were obtained by silica gel column chromatography. The sixth compound had higher activity to kill the larvae of Den-trolimus tabulaeformis with a corrected mortality rate of 80%. Seventeen compounds were separated and identified by GC/MS in the 6th group, of which 3compounds were more than 10%, 2-Piperidinone(14.02%), 2-coumaranone(47.10%), and Pyrrolo[1,2-a]Pyrazine-1,4-dione, hexahydro (21.05%). [Conclusion] 2-Piperidinone and 2-coumaranone had insec-ticidal activity (corrected mortality rate reached 83.32% and 91.61% respectively) and were the most important toxic sub-stances to control pests.

Key words:Dentrolimus tabulaeformis; Beauveria tenella; toxin; 2-Piperidinone; 2-coumaranone