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    Adsorptive removal of textile dyes from aqueous solutions by dead fungal biomass
    (Wiley, 2006) Asma, D; Kahraman, S; Cing, S; Yesilada, O
    Dead fungal biomass prepared from Phanerochaete chrysosporium and Funalia trogii was tested for their efficiency in removal of textile dyes. The effects of contact time, initial dye concentration, amount of dead biomass and agitation rate on dye removal have been determined. Removal of all dyes required a very short time (60 min). Experimental results show that, P. chrysosporium was more effective than F. trogii. An increase in the amount of dead biomass positively affected of the dye removal. The removal efficiency of different amount of biomass was in order 1g > 0.5 > 0.2 > 0.1 The highest removal was obtained at 150-200 rpm. Slightly lower removing activities were found at lower agitation rates. This study showed that it was possible to remove textile dyes by dead biomass of P. chrysosporium.
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    Biosorption of copper(II) by live and dried biomass of the white rot fungi Phanerochaete chrysosporium and Funalia trogii
    (Wiley-V C H Verlag Gmbh, 2005) Kahraman, S; Asma, D; Erdemoglu, S; Yesilada, O
    Biosorption is an innovative and alternative technology to remove heavy metal pollutants from aqueous solution using live, inactive and dead biomasses such as algae, bacteria and fungi. In this study, live and dried biomass of Phanerochaete chrysosporium and Funalia trogii was applied as heavy metal adsorbent material. Biosorption of copper(II) cations in aqueous solution by live and dried biomass of Phanerochaete chrysosporium and Funalia trogii was investigated to study the effects of initial heavy metal concentration, pH, temperature, contact time, agitation rate and amount of fungus. Copper(II) was taken up quickly by fungal biomass (live or dried) during the first 15 min and the most important factor which affected the copper adsorption by live and dried biomass was the pH value. An initial pH of around 5.0 allowed for an optimum adsorption performance. Live biomass of two white rot fungi showed a high copper adsorption capacity compared with dried biomass. Copper(II) uptake was found to be independent of temperature in the range of 20-45degreesC. The initial metal ion concentration (10-300 mg/L) significantly influenced the biosorption capacity of these fungi. The results indicate that a biosorption as high as 40-60% by live and dried biomass can be obtained under optimum conditions.
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    Decolorization of textile dyeing wastewater by Phanerochaete chrysosporium
    (Folia Microbiologica, 2003) Cing, S; Asma, D; Apohan, E; Yesilada, O
    The potential use of fungal pellets for decolorization of the textile dyeing wastewater was evaluated. The live pellets of the fungus Phanerochaete chrysosporium were found to remove more than 95% of the color of this wastewater within 1 d. The dye-removal capacity was a function of time and was proportional to the agitation rate; the optimum temperature was 30 degreesC. Both live and dead pellets were further examined in a repeated-batch mode for 5 d. The decolorization performance of live pellets remained high and stable for 5 d and they showed twice to thrice higher decolorization capacity than dead pellets.
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    Decolorization of textile dyes by fungal pellets
    (Elsevier Sci Ltd, 2003) Yesilada, O; Asma, D; Cing, S
    Decolorization of various dyes by pellets of white rot fungi was studied. All fungal pellets used could remove more than 75% of the color of these dyes in 24 h. Effect of various conditions such as initial pH, concentration of dye, amount of pellet, temperature and agitation on Astrazone blue dye decolorization activity of Funalia trogii was tested and the longevity of this decolorization activity under optimum conditions was investigated in repeated-batch mode. An increase in the amount of pellet positively affected the longevity of the decolorization activity while a decrease in dye decolorization capability of pellets occurred with increasing dye concentration in repeated-batch mode. Spectrophotometric and microscopic examinations of F trogii pellets showed that the process involved decolorization through microbial metabolism but not biosorption. The effect of glucose concentration and cheese whey on longevity of decolorization activity was also tested. The percentage of decolorization at a dye concentration of 264 mg/l remained high after 10 days operation especially in culture media with cheese whey. This study showed that white rot fungal pellets could effectively be used as an alternative to the traditional physicochemical process. (C) 2002 Elsevier Science Ltd. All rights reserved.
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    Decolourisation of the textile dye astrazon red FBL by Funalia trogii pellets
    (Elsevier Sci Ltd, 2002) Yesilada, O; Cing, S; Asma, D
    The effects of various conditions such as initial pH, dye concentrations, amount of pellet, temperature and agitation on decolourising activity of Funalia trogii were investigated. These, except initial pH, were all found to be important for dye decolourising activity of F. trogii. The decolourisation of the dye involved adsorption of the dye compound by fungal pellets at the initial stage, followed by the decolourisation through microbial metabolism. Heat-killed pellets were also tested for their ability to decolourise Astrazon Red dye. These pellets adsorbed the dye and 55% decolourisation was obtained in 24 h. But at the second cycle there was only 24% decolourisation. Our observation showed that Astrazon Red dye decolourisation by heat-killed pellets was mainly due to biosorption. The longevity of the decolourisation activity of F. trogii pellets was also investigated in repeated batch mode. Variations in the amount of pellet increased % decolourisation and stability of pellets. (C) 2001 Elsevier Science Ltd. All rights reserved.
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    Effect of paraquat on cellular defense enzymes and glutathione level of Funalia trogii
    (Springer, 2002) Asma, D; Yesilada, O
    The effect of paraquat on the activities of antioxidant defense and detoxifying enzymes of the white-rot fungus Funalia trogii was determined. Paraquat increased the activities of glutathione reductase (GR), glutathione transferase (GT) and superoxide dismutase at 1 mmol/L, while at 0.1 mmol/L it did not affect the activity of GR and GT. It depressed the catalase activity and the amount of glutathione at all concentrations used. Paraquat treatment probably depresses antioxidant defense components such as catalase and glutathione.
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    Effects of extended cold exposure on antioxidant defense system of rat hypothalamic-pituitary-adrenal axis
    (Pergamon-Elsevier Science Ltd, 2006) Yüksel, S; Asma, D
    The aim of our study was to investigate the effect of extended (48 h) cold (8 degrees C) exposure on oxidative stress and antioxidant defense system in hypothalamus and adrenal medulla, which are both key components of the hypothalamic-pituitary-adrenal (HPA) axis. Male albino Spraque-Dawley rats were randomly divided into two groups-the control group (n = 12) and the cold stress group (n = 12). Tissue superoxide dismutase (SOD), catalase (CAT), glutathion S-transferase (GST) and glutathion reductase (GR) activities and glutathion (GSH) were measured using chemical protocols. In cold stress groups CAT activities were significantly increased in adrenal medulla and hypothalamus of rats; however, SOD activities were decreased in both tissues. Sub-acute cold exposure resulted in a significant increase in GR activity while GST was decrease in both tissues studied. The amount of GSH was also enhanced in adrenal medulla and hypothalamus of cold-stressed rats when compared to controls. Extended exposure of cold caused synergic changes in the hypothalamic and adrenal medullary antioxidative enzyme activities. This results lead us to conclude that cold stress can disrupt the balance in an oxidant/antioxidant system and cause oxidative damage to HPA axis organs by altering the enzymatic and non-enzymatic antioxidant status. (c) 2006 Elsevier Ltd. All rights reserved.
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    Neutrophil superoxide anion production, and CAT and GSSGR activity in patients with tuberculosis
    (Luigi Ponzio E Figlio, 2003) Düzova, H; Asma, D; Emre, MH
    Tuberculosis (TB) is a chronic infection disease caused by Mycobacterium tuberculosis (MTB), as an intracellular pathogen. Various cytokines (TNF-alpha, IL's,GSF etc.) and other factors play important preventing roles and are secreted during the infection. It may cause changes in the metabolism of neutrophils. Production of superoxide anion and antioxidative enzymes activities, such as glutathione reductase (GSSGR) and catalase (CAT) may be changed during MTB infection in the host. In this study, the control group consisted of ten healthy subjects and ten patients with TB, were studied before anti-TB treatment. Level of superoxide anion production, activity of CAT and activity of GSSGR were studied from peripheral neutrophils of healthy subjects and patients with TB. Catalase activities of the neutrophils were significantly lower in patients with TB than normal subjects (p< 0.01). Glutathione reductase activities of the neutrophils were also significantly lower in patients with TB than normal subjects (p< 0.05). Superoxide anion production in the neutrophils did not show any significant difference between TB and normal subjects (p> 0.05). As a result, the activities of CAT and GSSGR were lower in the peripheral neutrophils of patients with TB than normal subjects, whereas superoxide anion production in the neutrophils did not differ between in TB patients than normal subjects.