Diclofenac (2-[(2,6-Dichlorophenyl)amino]benzeneacetic acid) is a non-steroidal anti-infl ammatory

drug. Due to excessive use of diclofenac, this drug has been detected in surface water, ground water and drinking

water. In our study, four fungal strain Trametes trogii, Aspergillus niger, Yarrowia lipolytica and Phanerochaete

chrysosporium were investigated in terms of diclofenac degradation potential. Trametes trogii was found to be

the most effi cient strain with 100% diclofenac degradation rate. Two hydroxylated diclofenac metabolites have

been identifi ed in culture medium. Crude laccase from T. trogii almost completely removed diclofenac with 97%

removal in 48 h. We suggest that the degradation of diclofenac depends on the cytochrome P450 enzyme system

and laccase activity. After 24 h incubation decrease in toxicity of diclofenac was confi rmed by Microtox test.

In environmental matrices there are mixtures of parent drug and its metabolites. The majority of research is focused on the biological activity and toxic effect of diclofenac (DCF), there is little research on the biological activity of DCF metabolites and their mixtures. The study focused on the assessment of the biological impact of DCF, its metabolites 4’-hydroxydiclofenac (4’-OHDCF) and 5-hydroxydiclofenac (5-OHDCF) and their mixtures on E. coli strains. The biological effects of tested chemicals were evaluated using the following: E. coli K-12 cells viability assay, the inhibition of bacteria culture growth, ROS (reactive oxygene species) generation and glutathione (GSH) content estimation. Moreover, we examined the influence of the mixture of DCF with caffeic acid (CA) on E. coli cells viability. Our results showed the strongest impact of the mixtures of DCF with 4’-OHDCF and 5-OHDCF on E. coli SM biosensor strains in comparison to parent chemicals. Similar results were obtained in viability test, where we noticed the highest reduction in E. coli cell viability after bacteria incubation with the mixtures of DCF with 4’-OHDCF and 5-OHDCF. Similarly, these mixtures strongly inhibited the growth of E. coli culture. We also found synergistic effect of caffeic acid in combination with DCF on E. coli cells viability. After bacteria treatment with the mixture of DCF and its metabolites we also noted the strongest amount of ROS generation and GSH depletion in E. coli culture. It suggests that oxidative stress is the most important mechanism underlying the activity of DCF and its metabolites.

The aim of this study was to investigate the cardiotoxic effect of the combination of tilmicosin and diclofenac sodium in sheep. Thirty-two sheep were used and were randomly divided into four equal groups as tilmicosin (T), diclofenac sodium (D), tilmicosin+diclofenac sodium (TD) and control (C) group. Group T received a single dose of tilmicosin, Group D was administered diclofenac sodium once a day for 3 days, and group TD was administered diclofenac and tilmicosin at the same doses as group T and D. Group C received NaCl in a similar way. The blood samples were taken before dosing and at 4th, 8th, 24th and 72nd hour post-dosing for measurement of cardiac markers such as H-FABP, cTn-I, CK-MB. H-FABP level of group TD was found to be significantly (p<0.05) higher than of group C at the 8th, 24th and 72nd hour and group D and T at the 72nd hour. cTn-I and CK-MB levels of group TD were found significantly (p<0.05) higher compared with other groups. In conclusion, the combined use of tilmicosin and diclofenac in sheep causes an increase in cardiac biomarkers and it can be stated that this combination of drugs may cause cardiac damage.

The pharmacokinetics of a diclofenac sodium was investigated in swine. A single intravenous (i.v.) or intramuscular (i.m.) injection of 5% diclofenac sodium (concentration = 2.5 mg · kg-1) was administered to 8 healthy pigs according to a two-period crossover design. The pharmacokinetic parameters were calculated by non-compartmental analysis with DAS2.1.1 software. After a single i.v. administration, the main pharmacokinetic parameters of diclofenac sodium injection in swine were as follows: the elimination half-time (T1/2β) was 1.32±0.34 h; the area under the curve (AUC) was (55.50±5.50 μg · mL-1 h; the mean residence time (MRT) was 1.60±0.28 h; the apparent volume of distribution (Vd) was 0.50±0.05 L · kg-1; and the body clearance (CLB) was 0.26±0.04 L · (h · kg)-1. After the single i.m. administration, the pharmacokinetic parameters were as follows: peak time (Tmax) was 1.19±0.26 h; and peak concentration (Cmax) was 11.61±5.99 μg mL-1. The diclofenac sodium has the following pharmacokinetic characteristics in swine: rapid absorption and elimination; high peak concentration; and bioavailability.

Many of the drugs used arc not completely metabolized in the human body and with urine and faces arc introduced into the sewage system. Finally, due to their incomplete removal during the conventional wastewater treatment process (CWTP), they can be released into the receiving water. One of the medicaments frequently detected in surface water is diclolcnac. The present study addresses the problem of diclofcnac removal in various aquatic samples using advanced oxidation processes (AOPs). The experiments were performed in distilled water and in biologically treated wastewater. The following AO Ps were applied: Fenlon 's reagent, UVand UV/H2O2-processes. The concentration of diclolcnac in distilled water corresponded to the concentration of this drug in human urine (ca. 20 mg-dm'). The real wastewater samples contained diclofcnac concentrations ranging from 630 to 790 ng-dm-'. The photodcgradation of diclolcnac was carried out in the photorcactor with a medium pressure Hg-vapor lamp (400 W). In the Fcnton's reaction different molar ratiosof H2O2/Fc'' were used. The diclotcnac mineralization (TOC removal) strictly depended on the amount of 1-1,0, applied in the Fcnton's reaction. Diclofcnac was rapidly degraded by direct photolysis (UV) and in UV/H2O2,-process both in distilled water and in wastewater samples. The results proved that the advanced oxidation processes arc cflcctive in diclofcnac removal from aquatic samples. The pseudo first order rate constants It)!' diclolcnac photodcgradation were determined.