title: Evaluation of in vitro and in vivo toxic effects of newly synthesized benzimidazole-based organophosphorus compounds.
abstract: This paper reports the toxic properties of eight newly synthesized benzimidazole-based organophosphorus (OP) compounds in Xenopus laevis in both in vivo and in vitro conditions. For both experiments, a commercial solution of azinphos methyl (AzM, Gusathion M WP25) was used as a reference compound. The 24-h median lethal concentrations (LC₅₀) of all tested compounds were determined for 46th stage tadpoles in the range of 9.54-140.0 μM. For evaluation of the lethality of the compounds, the activity of the enzyme biomarkers acetylcholinesterase (AChE), carboxylesterase, glutathione S-transferase (GST), glutathione peroxidase, glutathione reductase, lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase were determined in vivo in X. laevis tadpoles exposed to three concentrations (LC₅₀, LC₅₀/2, and LC₅₀/4) of tested compounds. All exposure concentrations of AzM and seven of eight tested compounds caused CaE inhibition in in vivo conditions. Furthermore, the AChE inhibition capacity of tested compounds in commercial electric eel AChE and in X. laevis homogenates and also CaE inhibition capacity in only X. laevis homogenates were assayed for a 30-min in vitro exposure period. Eight OP compounds did not inhibit AChE activity more than 23 percent, but AzM exposure inhibited AChE activity by 26 percent for X. laevis homogenates and 97 percent for electric fish AChE in in vitro conditions. Also, CaE inhibition levels in X. laevis tadpole homogenates were 46 percent for AzM and between 8 percent and 33 percent for other compounds in in vitro conditions.
authors.affiliation: Laboratory of Environmental Toxicology, Department of Biology, Faculty of Arts and Science, Inonu University, Malatya 44280, Turkey. abbas.gungordu@inonu.edu.tr
authors.forename: Abbas
authors.initials: A
authors.lastname: Güngördü
authors.forename: Nihat
authors.initials: N
authors.lastname: Sireci
authors.forename: Hasan
authors.initials: H
authors.lastname: Küçükbay
authors.forename: Ayşe
authors.initials: A
authors.lastname: Birhanli
authors.forename: Murat
authors.initials: M
authors.lastname: Ozmen
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D001387:Azinphosmethyl / Q000494:pharmacology; D001562:Benzimidazoles / Q000633:toxicity*; D043182:Carboxylesterase / Q000037:antagonists & inhibitors / Q000378:metabolism; D002800:Cholinesterase Inhibitors / Q000494:pharmacology; D004553:Electric Conductivity; D004789:Enzyme Activation / Q000187:drug effects; D005982:Glutathione Transferase / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007814:Larva / Q000187:drug effects / Q000201:enzymology; D007928:Lethal Dose 50; D009943:Organophosphorus Compounds / Q000138:chemical synthesis / Q000633:toxicity*; D010100:Oxygen / Q000032:analysis; D013696:Temperature; D014982:Xenopus laevis
chemical_list: D001562:Benzimidazoles; D002800:Cholinesterase Inhibitors; D009943:Organophosphorus Compounds; D001387:Azinphosmethyl; C031000:benzimidazole; D005982:Glutathione Transferase; D043182:Carboxylesterase; D000110:Acetylcholinesterase; D010100:Oxygen