Effect of a dietary essential oil mixture on performance of laying hens in the summer season

The experiment was conducted to evaluate the effects of dietary supplements of either an essential oil mixture (EOM) or a mannan oligosaccharide (MOS) as alternatives to an antibiotic feed additive (avilamycin) for layers kept under hot summer conditions. Four hundred and eighty 54-week old Nick-Brown hens were assigned to four dietary treatments. Each treatment consisted of four replications of 10 cages (three hens per cage). The treatment groups were: 1) Control: Basal diet without additive; 2) Basal diet plus antibiotic (10 mg avilamycin/kg feed); 3) Basal diet plus 1 g MOS/kg feed; 4) Basal diet plus 24 mg EOM/kg feed. Performance of laying hens was affected by dietary treatments. Dietary supplementation of EOM and MOS significantly increased egg production compared with control and antibiotic groups. There were no significant differences in feed consumption between treatments. The EOM significantly improved feed conversion ratio above that of the control group. Egg weights were significantly different between treatments. Laying hens consuming MOS produced significantly lower egg weights than the other groups, while egg weights in the EOM, antibiotic and control groups did not differ significantly. Cracked-broken egg rate was decreased by dietary addition of EOM, MOS and antibiotic compared with the control. Number of deaths among hens was significantly affected by dietary treatments with the number of deaths in the MOS treatment being significantly lower than in the other treatments. The performance of laying hens during the summer season could be maintained with inclusions of EOM and MOS in the diet. Keywords: Essential oils, mannan oligosaccharide, antibiotic, egg production, laying hen, summer seasonSouth African Journal of Animal Science Vol. 36 (4) 2006: pp. 215-22

İdiopatik trombositopenik purpuralı hastalarda klinik özellikler ve tedaviye cevabı belirleyen faktörler

TEZ1846Tez (Uzmanlık) -- Çukurova Üniversitesi, Adana, 1995.Kaynakça (s. 73-84) var.84 s. ; 30 cm.

Rotation mixing-assisted liquid-liquid microextraction: A new microextraction approach for the determination of priority phenols in water samples

In this study, a new sample pretreatment method termed as rotation mixing-assisted liquid-liquid microextraction combined with liquid chromatography with ultraviolet detection was developed for the determination of selected priority phenols in water samples. In this approach, a binary solvent system of water sample and low-density extraction solvent (1-dodecanol) was mixed at 80 rpm for 8 min with a circular rotation in the absence of a disperser solvent. Fine organic droplets were formed during continuous end-over-end action, which accelerated mass transfer of the analytes to the organic phase. After extraction, phase separation was performed by centrifugation and the enriched analytes in the floated extractant phase were determined. A series of parameters that influence extraction were investigated systematically. Under the optimized conditions, the enrichment factors and extraction recoveries ranged from 61 to 138 and 37 to 83%, respectively, that were comparable with those obtained by other mechanical methodologies, i.e., vortex agitation, magnetic stirring and ultrasonic treatment. The limits of detection were 0.29-0.63 ng mL-1. Relative standard deviations were less than 5.3% for intra-day and 8.3% for inter-day precision. This method has been also successfully applied to analyze real water samples at two different spiked concentrations and satisfactory recoveries were achieved. © The Royal Society of Chemistry 2016

A new solidified effervescent tablet-assisted dispersive liquid-liquid microextraction for the analysis of fungicides in fruit juice samples

A simple and rapid pretreatment method based on effervescent tablet-assisted dispersive liquid-liquid microextraction was introduced for the determination of three fungicides (azoxystrobin, chlorothalonil, and cyprodinil) in fruit juice samples followed by liquid chromatography-ultraviolet detection. The effervescent tablet composed of sodium dihydrogen phosphate, sodium carbonate and 1-dodecanol was prepared in a simple way. The ingredients consisting of the above three components were manually blended in an empty medicine strip and cooled in a refrigerator. Hence, an effervescent tablet was obtained within 5 min without the need for a press machine thanks to the solidification of 1-dodecanol at room temperature. In situ generation of carbon dioxide during the microextraction process enabled the dispersion of the extractant within the aqueous phase and enhanced the contact area both between phases. Under the optimized conditions, the extraction recoveries ranged from 53 to 88%. Good linearity was observed by the square of correlation coefficients better than 0.9980. Relative standard deviations were less than 4.8% for intra-day and 7.6% for inter-day precision at a concentration of 3.0 µg L-1 of each analyte. Limits of detection ranged from 0.09 (chlorothalonil) to 0.19 µg L-1 (azoxystrobin). The proposed new method was successfully applied for the analysis of three fungicides in real samples of fruit juices and satisfactory recoveries (76-104%) were achieved. © 2018 The Royal Society of Chemistry

Miniaturized matrix solid-phase dispersion coupled with supramolecular solvent-based microextraction for the determination of paraben preservatives in cream samples

An analytical method is presented for the determination of paraben preservatives in semisolid cream samples by matrix solid-phase dispersion combined with supramolecular solvent-based microextraction. Due to the oily and sticky nature of the sample matrix, parabens were first extracted from the samples by matrix solid-phase dispersion using silica as sorbent material with a clean-up performed with tetrahydrofuran in the elution step. The eluate (500 µL), 1-decanol (120 µL), and water (4.4 mL) were then mixed in a polyethylene pipette to form supramolecular solvent. Finally, the analytes in the supramolecular solvent were separated and determined by liquid chromatography with ultraviolet detection. Under optimal extraction conditions, the extraction recoveries of the studied compounds were obtained in the range of 63–83%. The limits of detection for the analytes were between 0.03 and 0.04 µg/g. The precision of the method varied between 4.0–6.7 (intraday) and 6.2–7.9% (interday). Finally, the optimized procedure was applied to the determination of the target preservatives in a variety of cream samples (diaper rash, skin allergy, face and hand moisturizing) with satisfactory recoveries (86–102%). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei

Gas-particle partitioning and seasonal variation of polycyclic aromatic hydrocarbons in the atmosphere of Zonguldak, Turkey

Atmospheric concentrations and gas-particle partition coefficients were determined for polycyclic aromatic hydrocarbons (PAHs) in the atmosphere of Zonguldak, Turkey between May 2007 and April 2008. Total concentrations of PAHs ranged from 0.52ngm-3 to 636ngm-3 in the particle phase and from 5.60ngm-3 to 725ngm-3 in the gas phase. The annual mean concentrations of PAHs in the particle and gas phase were found to be 114ngm-3 and 184ngm-3, respectively. Significant seasonal variations of particle and gas phase PAH concentrations were observed with higher levels during cold period. The distribution of PAHs between the particle and gas phase was investigated and it was found that three ring PAHs were associated primarily with the gas phase, four ring PAHs were distributed almost equally between the two phases and five and six ring PAHs were mainly associated with the particle phase. Gas-particle partition coefficients (Kp) of PAHs have been calculated and correlated with their subcooled liquid vapor pressures (PL-). The slopes (mr) varied from -0.63 to -0.23 were far from the theoretical value (-1) due to the short distance between the sampling point and the emission sources. The relationships between temperature and gas phase partial pressures of PAHs were examined using the Clausius-Clapeyron equation and the obtained positive slopes indicated that PAH concentrations increased with decreasing air temperature as a result of high dominance of local emissions. © 2010 Elsevier B.V

Low density solvent-based dispersive liquid-liquid microextraction for the determination of synthetic antioxidants in beverages by high-performance liquid chromatography

A simple and efficient method was established for the determination of synthetic antioxidants in beverages by using dispersive liquid-liquid microextraction combined with high-performance liquid chromatography with ultraviolet detection. Butylated hydroxy toluene, butylated hydroxy anisole, and tert-butylhydroquinone were the antioxidants evaluated. Experimental parameters including extraction solvent, dispersive solvent, pH of sample solution, salt concentration, and extraction time were optimized. Under optimal conditions, the extraction recoveries ranged from 53 to 96%. Good linearity was observed by the square of correlation coefficients ranging from 0.9975 to 0.9997. The relative standard deviations ranged from 1.0 to 5.2% for all of the analytes. Limits of detection ranged from 0.85 to 2.73 ng mL-1. The method was successfully applied for determination of synthetic antioxidants in undiluted beverage samples with satisfactory recoveries. © 2013 Hasan Çabuk and Mustafa Köktürk

Particle-associated polycyclic aromatic hydrocarbons in the atmospheric environment of Zonguldak, Turkey

Airborne fine (PM2.5) and coarse (PM2.5-10) particulate matter was collected from January to December in 2007 in Zonguldak, Turkey using dichotomous Partisol 2025 sampler. Fourteen selected polycyclic aromatic hydrocarbons (PAHs) in particulate matter were determined simultaneously by high-performance liquid chromatography with fluorescence detection (HPLC-FL) and seasonal distributions were examined. The source identification of PAHs in airborne particulates was performed by principal component analysis (PCA) in combination with diagnostic ratios. The predominant PAHs determined in PM2.5 were pyrene, fluoranthene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene. The total concentrations of PAHs were up to 464.0 ng m- 3 in fine and 28.0 ng m- 3 in coarse fraction in winter, whereas in summer times were up to 22.9 and 3.0 ng m- 3 respectively. Approximately 93.3% of total PAHs concentration was determined in PM2.5 in winter and 84.0% in summer. The concentration levels of PAHs fluctuate significantly within a year with higher means and peak concentrations in the winter compared to that of summer times. Higher benzo(a)pyrene-equivalent (BaPE) concentrations of PAHs were obtained for PM2.5 especially in winter. The results obtained from PCA in combination with diagnostic ratios revealed that coal combustion and vehicle emissions were the major pollutant sources for both PM2.5 and PM2.5-10 associated PAHs in studied area. Two principal components for PM2.5 and three for PM2.5-10 were identified and these accounted for 89.4 and 85.2% of the total variance respectively. The emissions from coal combustion were estimated to be the main source of PAHs in the ambient air particulates with contributions of 80.8% of total variance for PM2.5 and 53.8% for PM2.5-10. © 2008 Elsevier B.V. All rights reserved.2007-13-2-3 2003 K121120The authors would like to thank the State Planning Organization of Turkey, (2003 K121120) and the Zonguldak Karaelmas University (2007-13-2-3) for the opportunity and support to carry out this research

Meteorological variations of PM2.5/PM10 concentrations and particle-associated polycyclic aromatic hydrocarbons in the atmospheric environment of Zonguldak, Turkey

Airborne particulate matter (PM2.5 and PM10) concentrations were measured in Zonguldak, Turkey from January to December 2007, using dichotomous Partisol 2025 sampler. Collected particulate matter was analyzed for 14 selected polycyclic aromatic hydrocarbons (PAHs) by high-performance liquid chromatography with fluorescence detection (HPLC-FL). The seasonal variations of PM2.5 and PM10 concentrations were investigated together with their relationships with meteorological parameters. The maximum daily concentrations of PM2.5 and PM10 reached 83.3 µg m-3 and 116.7 µg m-3 in winter, whereas in summer, they reached 32.4 µg m-3 and 66.7 µg m-3, respectively. Total concentration of PM10-associated PAHs reached 492.4 ng m-3 in winter and 26.0 ng m-3 in summer times. The multiple regression analysis was performed to predict total PM2.5- and PM10-associated PAHs and benzo(a)pyrene-equivalent (BaPE) concentrations with respect to meteorological parameters and particulate mass concentrations with the determination coefficients (R2) of 0.811, 0.805 and 0.778, respectively. The measured mean values of concentrations of total PM2.5- and PM10-associated PAHs were found to be 88.4 ng m-3 and 93.7 ng m-3 while their predicted mean values were found to be 92.5 ng m-3 and 98.2 ng m-3, respectively. In addition, observed and predicted mean concentration values of PM2.5-BaPE were found to be 14.1 ng m-3 and 14.6 ng m-3. The close annual mean concentrations of measured and predicted total particulate related PAHs imply that the models can be reliably used for future predictions of particulate related PAHs in urban atmospheres especially where fossil fuels are mainly used for heating. © 2009 Elsevier B.V. All rights reserved.2007-13-2-3 2003K121120The authors would like to thank the State Planning Organization of Turkey (2003K121120) and the Zonguldak Karaelmas University (2007-13-2-3) for the opportunity and support to carry out this research