Abstract:

The biological character, toxicity and toxicity relative factors were influenced of Beauveria bassiana by subculturing, the effect on toxin production level of subculturing was investigated in this research. The B. bassiana strains D6-2 and L1-1 were subcultured on SDAY medium, to detect the influence of subculturing on production level at different generations of toxin methyl 3-methylbenzoate and 2-Coumaranone, by high performance liquid chromatography (HPLC) method. The inoculum at the same culturing time of different B. bassiana generations was collected, and its liposolubility portion was extracted by ethylalcohol and ethyl acetate sequentially, it showed via HPLC detection that 2-Coumaranone was detected in metabolic product of two strains F1 generation, but not in that of F2 to F5 generations, and there was no methyl 3-methylbenzoate detected in all samples of the two strains. However, there was other unknown product of metabolism was detected, and established a relative stable expression level in subculturing. There was difference on toxin species of different strains of B. bassiana, and subculturing was able to lower the production level of some toxin, it was possible one of the reasons of toxicity decline. It need further research for the other species of toxin expression level in different subculturing generations.