Evaluating the enantioselective distribution, degradation and excretion of epoxiconazole in mice following a single oral gavage.

ABSTRACT

1. The enantiomeric enrichment or degradation of epoxiconazole has been reported in grape, soil, tubifex and mealworm beetle. But, little is known about its enantioselective behaviors in mammals. 2. To further understand differences in the distribution, degradation and excretion of epoxiconazole enantiomers in vivo, male CD-1 mice were selected as the test model to investigate the enantioselective behaviors after a single oral gavage. Mice were sacrificed after 1 h, 3 h, 7 h, 12 h, 24 h, 48 h, 72 h treatment, blood, tissues and excretions were collected for epoxiconazole analysis by LC-MS/MS. 3. On the Lux-Cellulose-1 chiral column, an enrichment of the second eluting (+)-epoxiconazole was generally observed, and feces and urine showed similar EF with major tissues. 4. To elucidate the potential role of intestinal bacterial flora in stereospecific degradation of epoxiconazole, mice fecal flora were cultured in vitro and incubated with epoxiconazole for 48 h. Results showed that (-)-epoxiconazole was preferentially degraded by intestinal bacterial. 5. These results may provide useful information for risk assessment of epoxiconazole on non-target animals.