TY - JOUR
T1 - Acute Toxicity, Bioactivity, and Enantioselective Behavior with Tissue Distribution in Rabbits of Myclobutanil Enantiomers
AU - Sun, Mingjing
AU - Liu, Donghui
AU - Qiu, Xinxu
AU - Zhou, Qian
AU - Shen, Zhigang
AU - Wang, Peng
AU - Zhou, Zhiqiang
N1 - Publisher Copyright:
© 2014 Wiley Periodicals, Inc.
PY - 2014/8/17
Y1 - 2014/8/17
N2 - The enantioselective bioactivity against pathogens (Cercospora arachidicola, Fulvia fulva, and Phytophthora infestans) and acute toxicity to Daphnia magna of the fungicide myclobutanil enantiomers were studied. The (+)-enantiomer in an antimicrobial activity test was about 1.79-1.96 times more active than the (-)-enantiomer. In the toxicity assay, the calculated 24-h LC50 values of the (-)-form, rac-form and (+)-form were 16.88, 13.17, and 11.91 mg/L, and the 48-h LC50 values were 10.15, 9.24, and 5.48 mg/L, respectively, showing that (+)-myclobutanil was more toxic. Meanwhile, the enantioselective metabolism of myclobutanil enantiomers following a single intravenous (i.v.) administration was investigated in rabbits. Total plasma clearance value (CL) of the (+)-enantiomer was 1.68-fold higher than its antipode. Significant differences in pharmacokinetics parameters between the two enantiomers indicated that the high bioactive (+)-enantiomer was preferentially metabolized and eliminated in plasma. Consistent consequences were found in the tissues (liver, brain, heart, kidney, fat, and muscle), resulting in a relative enrichment of the low-activity (-)-myclobutanil. These systemic assessments of the stereoisomers of myclobutanil cannot be used only to investigate environmental and biological behavior, but also have human health implications because of the long persistence of triazole fungicide and enantiomeric enrichment in mammals and humans. Chirality 26:784-789, 2014.
AB - The enantioselective bioactivity against pathogens (Cercospora arachidicola, Fulvia fulva, and Phytophthora infestans) and acute toxicity to Daphnia magna of the fungicide myclobutanil enantiomers were studied. The (+)-enantiomer in an antimicrobial activity test was about 1.79-1.96 times more active than the (-)-enantiomer. In the toxicity assay, the calculated 24-h LC50 values of the (-)-form, rac-form and (+)-form were 16.88, 13.17, and 11.91 mg/L, and the 48-h LC50 values were 10.15, 9.24, and 5.48 mg/L, respectively, showing that (+)-myclobutanil was more toxic. Meanwhile, the enantioselective metabolism of myclobutanil enantiomers following a single intravenous (i.v.) administration was investigated in rabbits. Total plasma clearance value (CL) of the (+)-enantiomer was 1.68-fold higher than its antipode. Significant differences in pharmacokinetics parameters between the two enantiomers indicated that the high bioactive (+)-enantiomer was preferentially metabolized and eliminated in plasma. Consistent consequences were found in the tissues (liver, brain, heart, kidney, fat, and muscle), resulting in a relative enrichment of the low-activity (-)-myclobutanil. These systemic assessments of the stereoisomers of myclobutanil cannot be used only to investigate environmental and biological behavior, but also have human health implications because of the long persistence of triazole fungicide and enantiomeric enrichment in mammals and humans. Chirality 26:784-789, 2014.
KW - acute toxicity
KW - bioactivity
KW - enantioselective degradation
KW - myclobutanil enantiomer
KW - rabbit
UR - http://www.scopus.com/inward/record.url?scp=84938694532&partnerID=8YFLogxK
U2 - 10.1002/chir.22353
DO - 10.1002/chir.22353
M3 - Review article
C2 - 25043148
AN - SCOPUS:84938694532
SN - 0899-0042
VL - 26
SP - 784
EP - 789
JO - Chirality
JF - Chirality
IS - 12
ER -