Determination of destruxins, cyclic peptide toxins, produced by different strains of Metarhizium anisopliae and their mutants induced by ethyl methane sulfonate and ultraviolet using HPLC method

Metarhizium anisopliae produces a family of cyclic peptide toxins, destruxi ns (DTXs), which exhibit various insecticidal activity. Four major DTXs hav e been separated by HPLC and identified by the liquid chromatography electr ospray mass spectrometry (LC-ESI-MS) methods. Strain F061 of M. anisopliae produced large amounts of (DTXs), especially DTX-A (12.84 +/- 0.04 mug/ml), DTX-B (66.89 +/- 2.57 mug/ml) and DMDB (1.41 +/- 0.13 mug/ml). High levers of DTX-E (4.19 +/- 0.13 mug/ml) were produced by strain F007 of M. anisopl iae. The results of our studies also showed that either ethyl methane sulfo nate GEMS) or ultraviolet (UV) can significantly increase the production of DTXs. Mutant 61E-9 produced high levels of DTX-A (30.05 +/- 1.97 mug/ml), DTX-B (110.37 +/- 10.02 mug/ml) and DMDB (8.30 +/- 0.45 mug/ml). High level s of DTX-E (20.59 +/- 2.65 mug/ml) were produced by mutant 7E-3. Both mutan t strains are suitable for industrial fermentation processes and possess a wide range of potential applications in the area of metabolic toxin product ion. (C) 2001 Elsevier Science Ltd. All rights reserved.