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Öğe Assessment of Pb2+ removal capacity of lichen (Evernia prunastri): application of adsorption kinetic, isotherm models, and thermodynamics(Springer Heidelberg, 2019) Senol, Zeynep Mine; Gul, Ulkuye Dudu; Simsek, SelcukBiological materials play a significant role in the treatment of heavy metal-contaminated soil and wastewater. In this study, the Pb2+ biosorption potential of lichen Evernia prunastri, extensively available at a forest in Bilecik-Turkey, was investigated at batch-scale level. The optimal conditions were determined and the adsorption isotherms, kinetics, and thermodynamic calculations were also done. In order to have detailed knowledge about metal biosorption, SEM, FTIR, and BET analyses were carried out before and after the biosorption process. The optimal pH was found pH 4 and the maximum metal uptake capacity was found as 0.067 mol kg(-1). The results of this study indicate that the lichen was effectively applied to the removal of Pb2+ process as an inexpensive biosorbent from industrial wastewater.Öğe Bio-sorption of bisphenol a by the dried- and inactivated-lichen (Pseudoevernia furfuracea) biomass from aqueous solutions(Springer, 2020) Senol, Zeynep Mine; Gul, Ulkuye Dudu; Gurkan, RamazanBisphenol A (BPA), which is known as one of the endocrine-disrupting chemicals (EDCs) with hydrophilic hydroxyl groups and hydrophobic aromatic groups, has been widely used in plastic industries. The chemical waste from the industry is sometimes discharges into lakes and rivers, and then these surface waters can be polluted. So, this article aims to investigate the bio-sorption process of BPA by the inactivated lichen (Pseudoevernia furfuracea) biomass from aqueous solution. At initial, the effect of the variables such as initial BPA concentration, solution pH, temperature, contact time and recovery rate on the bio-sorption process was investigated. From the optimal results, it has been observed that the highest removal efficiency is approximately 64% at a contact time of 3-h, the bio-sorbent concentration of 9 mg/L, initial BPA concentration of 40 mg/L, and agitation speed of 150 rpm at pH 5.0. In explaining the bio-sorption potential of lichen biomass, Langmuir and/or Redlich-Peterson isotherms with two and three parameters, respectively were observed to be better fit with the experimental isotherm data (R-2 = 0.982). From equilibrium data based on difference between the measured and predicted results (q(e, exp)and q(e, pre)), it was shown that biosorption of BPA could be best described by the pseudo second order kinetic model with minimum sum of square error of 2.61%. In addition, it shows more film diffusion, and partly pore diffusion in linearity region in terms of kinetic sorption behaviors of BPA in the rate-limiting step as well as intra-particle diffusion according to Boyd's kinetic model with better regression coefficient than 0.981 when compared to the other used kinetic models, including Bangham's pore diffusion and Elovich kinetic models (with R(2)of 0.958 and 0.929). The thermodynamic studies showed that the biosorption process was spontaneous, and chemically feasible. Therefore, due to be low-cost, eco-friendly character, wide availability and easily accessible, the lichen biomass could be used as a promising bio-sorbent for the removal of BPA from the environment and wastewater effluents.Öğe Effective UO22+ removal from aqueous solutions using lichen biomass as a natural and low-cost biosorbent(ELSEVIER SCI LTD, 2019) Gul, Ulkuye Dudu; Senol, Zeynep Mine; Gursoy, Nevcihan; Simsek, SelcukThe UO22+ biosorption properties of a lichen, Evernia prunasui, from aqueous solutions were investigated. The widely occurring lichen samples were collected from the forest in Bilecik-Turkey. The UO22+ biosorption onto lichen was characterized by FT-IR and SEM-EDX analysis techniques before and after biosorption. The effects of the solution pH, biosorbent dosage, UO22+ concentration, contact time, and temperature on UO22+ biosorption on lichen sample were studied by using the batch method. The isotherm experimental data were described using isotherm models of Langmuir, Freundlich and Dubinin Radushkevich. The maximum UO22+ biosorption capacity of the lichen sample was estimated by the Langmuir equation to be 0.270 mol kg(-1). The adsorption energy from the Dubin Radushkevich model was found to be 8.24 kJ mol(-1). Kinetic data determined that the biosorption was best described by the pseudo-second-order kinetic model. Thermodynamic findings showed that the biosorption process was endothermic, entropy increased and spontaneous. In conclusion, the lichen appears to be a promising biosorbent for the removal of UO22+ ions from aqueous solutions because of high biosorption capacity, easy usability, low cost, and high reusability performance.Öğe Synthesis of Benzimidazole-1,2,4-triazole Derivatives as Potential Antifungal Agents Targeting 14α-Demethylase(Amer Chemical Soc, 2023) Guzel, Emir; Cevik, Ulviye Acar; Evren, Asaf Evrim; Bostanci, Hayrani Eren; Gul, Ulkuye Dudu; Kayis, Ugur; Ozkay, YusufInvasive fungal infections (IFIs) are increasing as major infectious diseases around the world, and the limited efficacy of existing medications has resulted in substantial morbidity and death in patients due to the lack of effective antifungal agents and serious drug resistance. In this study, a series of benzimidazole-1,2,4-triazole derivatives (6a-6l) were synthesized and characterized by 1H NMR, 13C NMR, and HR-MS spectral analysis. All the target compounds were screened for their in vitro antifungal activity against four fungal strains, namely, C. albicans, C. glabrata, C. krusei, and C. parapsilopsis. The synthesized compounds exhibited significant antifungal potential, especially against C. glabrata. Three compounds (6b, 6i, and 6j) showed higher antifungal activity with their MIC values (0.97 mu g/mL) compared with voriconazole and fluconazole. Molecular docking provided a possible binding mode of compounds 6b, 6i, and 6j in the 14 alpha-demethylase active site. Our studies suggested that the benzimidazole-1,2,4-triazole derivatives can be used as a new fungicidal lead targeting 14 alpha-demethylase for further structural optimization. In addition, their effects on the L929 cell line were also investigated to evaluate the cytotoxic effects of the compounds. SEM analyses were performed to examine the effects of compounds 6a, 6i, and 6j on C. glabrata cells under in vivo experimental conditions.Öğe Synthesis, DFT Calculations, In Silico Studies, and Antimicrobial Evaluation of Benzimidazole-Thiadiazole Derivatives(Amer Chemical Soc, 2024) Isik, Aysen; Acar Cevik, Ulviye; Karayel, Arzu; Ahmad, Iqrar; Patel, Harun; Celik, Ismail; Gul, Ulkuye DuduIn this study, a series of new benzimidazole-thiadiazole hybrids were synthesized, and the synthesized compounds were screened for their antimicrobial activities against eight species of pathogenic bacteria and three fungal species. Azithromycin, voriconazole, and fluconazole were used as reference drugs in the mtt assay. Among them, compounds 5f and 5h showed potent antifungal activity against C. albicans with a MIC of 3.90 mu g/mL. Further, the results of the antimicrobial assay for compounds 5a, 5b, 5f, and 5h proved to be potent against E. faecalis (ATCC 2942) on the basis of an acceptable MIC value of 3.90 mu g/mL. The cytotoxic effects of compounds that are effective as a result of their antimicrobial activity on healthy mouse fibroblast cells (L929) were evaluated. According to HOMO-LUMO analysis, compound 5h (with the lower Delta E = 3.417 eV) is chemically more reactive than the other molecules, which is compatible with the highest antibacterial and antifungal activity results. A molecular docking study was performed to understand their binding modes within the sterol 14-alpha demethylase active site and to interpret their promising fungal inhibitory activities. Molecular dynamics (MD) simulations of the most potent compounds 5f and 5h were found to be quite stable in the active site of the 14-alpha demethylase (5TZ1) protein.
