NON-EXTRACTIVE METABOLISM STUDY OF E-DESTRUXIN AND A-DESTRUXIN IN THELOCUST, LOCUSTA-MIGRATORIA L .3. 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 me dia, a method was developed with direct injection on to a liquid chrom atographic (LC) column. Either slightly lipophilic C-1 and C-4 ''wide- pore'' packings or the column-switching approach with a guard column w ere used. To confirm the results of the direct LC analysis, a ''classi cal approach'' with pretreatment prior to injection on to a C-8 packed column was also developed. Further, parallel fast atom bombardment MS monitoring in the negative-ion mode was carried out on the same biolo gical samples, to obtain complementary information on the destruxin me tabolism in locusts. Thus, the behaviours of E and A destruxin were ex amined in vivo in different organs of locusts. For E destruxin, severa l detoxication processes could be observed, such as hydrolysis and con jugation with glutathione.