Search

Cadmium(II) is an important ecotoxic pollutant and may cause health problems if accumulated in the human body. This study focused on the removal of cadmium(II) from aqueous solutions using newly isolated fungus dry mass as the adsorber. The fungus was isolated from soil and identified as Fenellia nivea, based on 18S rRNA sequence analysis. Cadmium(II) biosorption studies were carried out as a function of pH, biomass dose, initial metal concentration, contact time, and temperature. The pH of the aqueous solution strongly influenced the removal percent of Cd(II). The highest cadmium removal yield was obtained at pH 7 (4.9 mg/g) as well as below pH 4, very low yield biosorption of Cd(II) was observed. In the first 5 min, almost 50% Cd(II) ions were removed from the solution and reached equilibrium within 1,440 min at pH 7. Adsorption isotherm follows Langmuir model as well as the dimensionless constant is zero that corresponds to the irreversible adsorption of Cd(II) ions on biomass. The reaction rate constant for the pseudo-second-order adsorption process was found as 3.74 × 10-3 g/mg min. The adsorption process was determined as endothermic and spontaneous with negative standard Gibbs energy change. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Pharmaceuticals are widely used for treating human and animal diseases. Naproxen [(S) 6-methoxy-α-methyl-2-naphthalene acetic acid] and its sodium salt are members of the α-arylpropionic acid group of nonsteroidal anti-inflammatory drugs. Due to excessive usage of naproxen, this drug has been determined even in drinking water. In this study, four fungal strains Phanerochaete chrysosporium, Funalia trogii, Aspergillus niger, and Yarrowia lipolytica were investigated in terms of naproxen removal abilities. According to LC/MS data, A. niger was found the most efficient strain with 98% removal rate. Two main by-products of fungal transformation, O-desmethylnaproxen and 7-hydroxynaproxen, were identified by using LC/MS, 1HNMR, and 13CNMR. Our results showed that O-demethylation and hydroxylation of naproxen is catalyzed by cytochrome P450 enzyme system.