Non-extractive metabolism study of E and A destruxins in the locust, Locusta migratoria L. III. Direct high-performance liquid chromatographic analysis and parallel fast atom bombardment mass spectrometric monitoring.

To study the behavior of the toxins E and A destruxin in biological media, a method was developed with direct injection on to a liquid chromatographic (LC) column. Either slightly lipophilic C1 and C4 "wide-pore" packings or the column-switching approach with a guard column were used. To confirm the results of the direct LC analysis, a "classical approach" with pretreatment prior to injection on to a C8 packed column was also developed. Further, parallel fast atom bombardment MS monitoring in the negative-ion mode was carried out on the same biological samples, to obtain complementary information on the destruxin metabolism in locusts. Thus, the behaviours of E and A destruxin were examined in vivo in different organs of locusts. For E destruxin, several detoxication processes could be observed, such as hydrolysis and conjugation with glutathione.