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Öğe Antimicrobial activity of trans-cinnamic acid and commonly used antibiotics against important fish pathogens and nonpathogenic isolates(Oxford Univ Press, 2018) Yilmaz, S.; Sova, M.; Ergun, S.Aims Antibiotics and several other chemicals have been used to prevent fish diseases. However, this situation results in economic loss for the companies in the aquaculture industry and most importantly it pollutes the environment. Cinnamic acid is a naturally occurring aromatic acid and is considered to be safe for human consumption. Therefore, in this study, the antibacterial activity of trans-cinnamic acid and commonly used antibiotics, namely chloramphenicol, vancomycin, streptomycin and erythromycin, were tested against 32 bacteria, including fish pathogens, nonpathogenic isolates and collection strains. Methods and Results Trans-cinnamic acid was applied against the bacteria using the disc diffusion and microdilution method under in vitro conditions. Antibiotics were also tested under similar conditions against all tested bacteria using the disc diffusion method. The results show that among 32 bacterial strains trans-cinnamic acid exhibited potent inhibitory effect on the Gram-negative fish pathogen Aeromonas sobria. In addition, a moderate inhibition of trans-cinnamic acid of fish pathogens Aeromonas salmonicida, Vibrio (Listonella) anguillarum, Vibrio crassostreae and Yersinia ruckeri was also observed for trans-cinnamic acid in our study. On the contrary, the majority of nonpathogenic intestinal isolates were resistant to trans-cinnamic acid. Conclusions To the best of our knowledge, this is the first report on the antimicrobial activity of trans-cinnamic acid on 24 of the studied bacteria isolated from fish. In conclusion, trans-cinnamic acid can be used as an environmentally friendly alternative additive to prevent and control primarily A. sobria, as well as other pathogenic bacteria such as A. salmonicida, V. anguillarum, V. crassostreae and Y. ruckeri. Significance and Impact of the Study This study indicated that trans-cinnamic acid may present an environmentally friendly alternative therapeutic agent against A. sobria infections in the aquaculture industry.Öğe Effects of lead nitrate on haematological and immunological parameters in the tilapia (Oreochromis mossambicus, L. 1758)(Elsevier Ireland Ltd, 2011) Kaya, H.; Akbulut, M.; Celik, E. S.; Yilmaz, S.; Aydin, F.; Duysak, M.[Anstract Not Available]Öğe Electroanalytical Investigation of Paracetamol on Glassy Carbon Electrode by Voltammetry(Esg, 2015) Engin, C.; Yilmaz, S.; Saglikoglu, G.; Yagmur, S.; Sadikoglu, M.An electroanalytical method was developed for the direct quantitative determination of paracetamol (or acetaminophen) in tablet dosage forms based on its oxidation behavior. The electrochemical oxidation and determination of paracetamol were easily carried out on glassy carbon electrode (GCE) using a variety of voltammetric techniques. The electrochemical measurements were carried out on GCE in various buffer solutions in the pH range from 0.51 to 12.00 by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The dependence of pH on the anodic peak current and peak potential was investigated. Acetate buffer (pH 4.51) was selected for analytical purposes. Scan rate studies were also completed. The diffusion controlled nature of the peak was established. A linear calibration curve for DPV analysis was constructed in the paracetamol concentration range from 4x10(-6) mol/L to 1x10(-4) mol/L. Limit of detection (LOD) and limit of quantification (LOQ) were obtained as 3.69x10(-7) mol/L and 1.23x10(-6) mol/L respectively. Validation of applied voltammetric techniques was checked with recovery studies.Öğe Electroanalytical investigation of paracetamol on glassy carbon electrode by voltammetry(Electrochemical Science Group, 2015) Engin, C.; Yilmaz, S.; Saglikoglu, G.; Yagmur, S.; Sadikoglu, M.An electroanalytical method was developed for the direct quantitative determination of paracetamol (or acetaminophen) in tablet dosage forms based on its oxidation behavior. The electrochemical oxidation and determination of paracetamol were easily carried out on glassy carbon electrode (GCE) using a variety of voltammetric techniques. The electrochemical measurements were carried out on GCE in various buffer solutions in the pH range from 0.51 to 12.00 by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The dependence of pH on the anodic peak current and peak potential was investigated. Acetate buffer (pH 4.51) was selected for analytical purposes. Scan rate studies were also completed. The diffusion controlled nature of the peak was established. A linear calibration curve for DPV analysis was constructed in the paracetamol concentration range from 4x10-6 mol/L to 1x10-4 mol/L. Limit of detection (LOD) and limit of quantification (LOQ) were obtained as 3.69x10-7 mol/L and 1.23x10-6 mol/L respectively. Validation of applied voltammetric techniques was checked with recovery studies. © 2015 The Authors.Öğe Electrocatalytic oxidation of hydrazine on poly(4-aminobenzene sulfonic acid)-modified glassy carbon electrode(Pleiades Publishing Inc, 2016) Sadikoglu, M.; Yilmaz, S.; Kurt, I.; Selvi, B.; Sari, H.; Erduran, N.; Usta, E.Electrocatalytic oxidation of hydrazine (HZ) was studied on an stable modified glassy carbon electrode (GCE) based on poly (4-aminobenzene sulfonic acid) (4-ABSA) film. The 4-ABSA-modified glassy carbon electrode was prepared by electrochemical polymerization technique in phosphate buffer solution (PBS) (pH 7.0) and its electrochemical behavior were studied by cyclic voltammetry (CV). The polymer filmmodified electrode has very high catalytic ability for electrooxidation of HZ, which appeared as a reduced overpotential in a wide operational pH range of 5-10. Limit of detection (LOD) and limit of quantification (LOQ) were obtained as 1.31 x 10(-7) and 4.35 x 10(-7) M for CV; 7.89 x 10(-8) and 2.63 x 10(-7) M for CA, respectively. The results of experiments showed that prepared modified electrode have good stability, sensitivity and reproducibility for at least one month if stored dry in air.Öğe Electrocatalytic Oxidation of Hydrazine on Poly(4-Aminobenzene Sulfonic Acid)-Modified Glassy Carbon Electrode (vol 52, pg 539, 2016)(Maik Nauka/Interperiodica/Springer, 2016) Sadikoglu, M.; Yilmaz, S.; Kurt, I.; Selvi, B.; Sari, H.; Erduran, N.; Usta, E.[Anstract Not Available]Öğe Electrocatalytic oxidation of moxifloxacin hydrochloride on modified glassy carbon surface and determination in Avelox tablets(Bulgarian Academy of Sciences, 2019) Sadikoglu, M.; Soylu, U.I.; Yilmaz, S.; Selvi, B.; Yildiz Seckin, H.; Nosal-Wiercinska, A.This work presents an electroanalytical method for the determination of moxifloxacin hydrochloride (MOX) in tablets. The surface of the glassy carbon electrode (GCE) was modified by electrochemical polymerization of 4-aminobenzene sulfonic acid in phosphate buffer solution (pH 7.0).The oxidative behavior of MOX was studied at glassy carbon and modified glassy carbon electrodes in different buffer systems using the cyclic voltammetry technique. The modified glassy carbon electrode (poly(4-ABSA/GCE) has very high catalytic ability for electrooxidation of MOX. Acetate buffer (pH 5.0) was selected as the optimum medium for the oxidation of MOX at poly(4-ABSA/GCE) due to the highest electronic signal increase obtained. Differential pulse voltammetry (DPV) and chronoamperometry (CA) techniques were used for voltammetric determination of MOX. The values of limit of detection (LOD) and limit of quantification (LOQ) were determined to be 3.19×10 -7 M and 1.06×10 -6 M for DPV; and 5.50×10 -7 M and 1.83×10 -6 M for CA, respectively. A highly sensitive electroanalytical method for the determination of MOX in Avelox tablets by DPV was described. © 2019 Bulgarian Academy of Sciences, Union of Chemists in BulgariaÖğe Electrooxidation of Phenazopyridine Hydrochloride and its Voltammetric and HPLC Determination in Human Urine and Tablet Dosage Form(Esg, 2013) Yagmur, S.; Yilmaz, S.; Sadikoglu, M.; Saglikoglu, G.; Yildiz, M.; Yengin, C.; Kilinc, E.The electrochemical oxidation of phenazopyridine hydrochloride (PAP) was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques at ultra trace graphite electrode (UTGE). PAP exhibited a diffusion controlled process which is pH dependence. The dependence of the current and potential on pH, the concentration and nature of buffer, and scan rate was investigated to optimize the experimental conditions for the determination of PAP. It was found that the optimum buffer for the determination of PAP is 0.1 NaOH solutions with the pH 12.97. In the concentration range from 6.0x10(-8) to 1.0x10(-6) M, the current measured by DPV present a good linear property as a function of the concentration of PAP. Limit of detection (LOD) and limit of quantification (LOQ) were obtained as 8.1x10(-10) and 2.7x10(-9) M, respectively. PAP was determined in human urine and tablet dosage form. Precision and accuracy of the developed technique were checked by recovery studies in spiked urine and tablet dosage form. In addition, for the comparison, high performance liquid chromatography (HPLC) technique was applied for the determination of PAP in the same samples.Öğe Influence of Tribulus terrestris extract on the survival and histopathology of Oreochromis mossambicus (Peters, 1852) fry before and after Streptococcus iniae infection(Wiley, 2014) Yilmaz, S.; Ergun, S.; Kaya, H.; Gurkan, M.The aim of this study was to determine the effects of Tribulus terrestris extract (TT) on growth performance, disease resistance and histopathological changes in intestine and liver tissues of Oreochromis mossambicus (Peters, 1852) first-feeding fry before and after exposure to Streptococcus iniae. Five iso-nitrogenous and isocaloric diets were formulated to contain 0 (control), 200, 400, 600, and 800 mg kg(-1) TT. After feeding for 45 days, fish were infected with S. iniae and mortalities recorded. Final weight, weight gain and SGR of tilapia fry fed the 400 mg kg(-1) TT diet were significantly greater than that of control diet. In the challenge experiment, the best survival rate was obtained with 400 mg kg(-1) TT supplementation. Infection by S. iniae appeared to have a negative effect on histopathological findings and outcome than did TT-800 used alone. However, administration of TT (200 or 400 mg extract kg(-1)) resulted in overall improvement in the intestine and liver histopathology, emphasizing the protective potential of TT. The present study suggests the protective potential of TT in alleviating intestinal and hepatic damage that can occur after a S. iniae infection. It was concluded that 400 mg kg(-1) TT can enhance growth and disease resistance during first-feeding of O. mossambicus fry. This suggests that TT may be an alternative to antibiotics in controlling streptococcal disease in tilapia culture.Öğe Monitoring of trace metals, biochemical composition and growth of Axillary seabream (Pagellus acarne Risso, 1827) in offshore copper alloy mesh cages(Natl Centre Marine Research, 2016) Yigit, M.; Celikkol, B.; Bulut, M.; Decew, J.; Ozalp, B.; Yilmaz, S.; Kaya, H.The study was conducted to assess trace metal contents, biochemical composition and growth performance of axillary seabream (Pagellus acarne Risso, 1827) cultured in a copper alloy mesh cage. A total of 400 axillary seabream (initial mean weight: 176.0 +/- 14.0 g), a new candidate species for the Mediterranean aquaculture, were stocked into a high-density polyethylene frame gravity cage and fed a commercial seabream diet for a period of 6 months. At the end of the feeding trial, fish reached a final weight of 264.8 +/- 16.8 g with a weight increase of 88.8 g and a feed conversion rate of 2.51. Overall, relative growth rate, specific growth rate and feed conversion ratio were satisfactory and comparable to the pelagic fishes such as gilthead seabream or European seabass, which are presently the main fish species for the Mediterranean aquaculture industry. Trace elements in fish grown in copper alloy net cages over a 6-month period showed satisfactory results, as the metal concentrations in fish tissues such as liver, skin, muscle and gills were below the reported upper limits for human consumption, indicating that copper alloy net is an acceptable and safe material for finfish cage aquaculture. Furthermore, from the growth performance data obtained in the present study, it can be concluded that axillary seabream showed potential for cage farming, and thus is a promising new candidate for the Mediterranean aquaculture industry.Öğe Radiodiagnostic examination of common carp (Cyprinus carpio, L. 1758) vertebra exposed to phosalone(Elsevier Ireland Ltd, 2011) Kaya, H.; Celik, E. S.; Akbulut, M.; Yilmaz, S.; Aydin, S.; Duysak, M.; Aydin, F.[Anstract Not Available]Öğe Synthesis, spectral properties, and antimicrobial activity of 2-arylamino,-2,4,4,6,6-pentachloro-1,3,5,2?5,4?5, 6?5-triazatriphosphines and poly[bis(4-fluorophenylamino)phosphazene](Maik Nauka/Interperiodica/Springer, 2007) Yildiz, M.; Yilmaz, S.; Dolger, B.2-(4-Chloro and 4-fluorophenylamino)-2,4,4,6,6-pentachloro-1,3,5,2 lambda(5),4 lambda(5),6 lambda(5)-triazatriphosphinines and poly [bis(4-fluoropwhenylamino)phosphazene] were synthesized by reactions of 4-fluoroaniline and 4-chloroaniline with 2,2,4,4,6,6-hexachloro-1,3,5,2 lambda(5),4 lambda(5),6 lambda(5)-triazatriphosphinine and poly(dichlorophosphazene), respectively, in tetrahydrofuran under argon at -20 degrees C, followed by heating under reflux. The products were isolated by column chromatography and were characterized by FTIR, NMR (H-1, C-13, P-31), and mass spectra, termogravimetry, and high-performance liquid chromatography. Antimicrobial activity of the monomeric compounds and polymer against 9 bacteria and 5 yeast cultures was evaluated by the disk diffusion method in dimethyl sulfoxide relative to a number of commercial antibiotics and antifungal agents. Aminophosphazene derivatives exhibited a broad spectrum of activity against both Gram-positive and Gram-negative bacterial with a magnitude comparable to reference antimicrobial agents. The polymeric product turned out to be more potent than the monomeric compounds.Öğe The Quantitative Detection of Phenylephrine in Pharmaceutical Preparations and Spiked Human Urine by Voltammetry(Pleiades Publishing Inc, 2018) Yagmur, S.; Ture, M.; Saglikoglu, G.; Sadikoglu, M.; Yilmaz, S.A voltammetric method was used for the quantitative detection of phenylephrine in pharmaceutical preparations and spiked human urine. The electrochemical measurements were carried out in various buffer solutions in the pH range from 0.51 to 12.00 on ultra-trace graphite electrode (UTGE) by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. The dependence of pH on the oxidation peak current and peak potential was investigated. Britton-Robinson buffer (pH 8.02) was selected for analytical purposes. The peak was established to be diffusion controlled nature of electrode. A linear calibration curve for DPV analysis was constructed in the phenylephrine concentration range from 8 x 10(-6) to 1 x 10(-4) M. Limits of detection (LOD) and quantification (LOQ) were obtained as 2.07 x 10(-7) M and 6.91 x 10(-6) M respectively. The repeatability, accuracy and precision of the developed technique were checked in spiked urine and pharmaceutical preparations.Öğe Voltammetric study of aciclovir using controled grow mercury drop electrode(Polskie Towarzystwo Chemiczne-Polish Chemical Soc, 2007) Skrzypek, S.; Ciesielski, W.; Yilmaz, S.The electrochemical properties of aciclovir (Acy) were studied by square wave voltammetric method (SWV) over pH range 1.5-8.0 using a controlled growth mercury, drop electrode (CGMDE). In the acid medium the cathodic peak current was observed. Surface catalytic electrode mechanism based on the hydrogen evolution reaction was analyzed. The dependence of the peak current at about -1.3 V vs Ag/AgCI electrode on pH, buffer concentration, nature of the buffer, amplitude, frequency and scan rate was investigated. The best results were obtained in solution of nitric acid at pH 1.9. This electroanalytical procedure enabled to determine aciclovir in the concentration range 2 x 10(-7)-2 x 10(-6) mol L-1. Repeat-ability, precision and accuracy of the developed method were checked. The detection and quantification limits were found to be 7 x 10(-8) and 2 x 10(-7) mol L-1 respectively.
