Análisis de algunos aspectos físicos, químicos y microbiológicos de las muestras de miel producidas y consumidas en Turquía

Analysis of honey produced in the western part of Turkey was carried out in this study. Fifty honey samples, collected from the local market in this region were analyzed for their physicochemical parameters including hydroxymethylfurfural (HMF), electrical conductivity, sucrose, free acidity, moisture and water insoluble impurities, in addition to pathogenic microorganisms present. HMF amounts determined in 47 samples were found to be between 1.9 and 98.0 mg/kg with good reproducibilities (%RSD: 3.2% or better). There were no pathogenic microorganisms in any of the investigated samples. Electrical conductivity that gives information about their mineral contents was measured, and the mean value was found to be 0.33 mS/cm (N=34). In general, most of the samples were considered to meet the requirements of Turkish Food Codex and European Commission Directives.En este estudio se analizó muestras de miel producida en la zona oeste de Turquía. Se trabajó con 50 muestras del mercado local de la región, en las cuales se determinaron parámetros físico-químicos incluyendo el hidroximetilfurfural (HMF), conductividad eléctrica, sacarosa, acidez libre, humedad e impurezas insolubles en agua además de microorganismos patógenos presentes. Las cantidades de HMF determinadas en 47 muestras oscilaron entre 1,9 y 98,0 mg/kg con buena desviación estándar de la reproducibilidad (% de RSD/DSR 3,2% o mejor). No se encontraron microorganismos patógenos en ninguna de las muestras analizadas. La conductividad eléctrica, que aporta información sobre el contenido mineral, resulta en un promedio de 0,33 mS/cm (N=34). En general se encontró que la mayoría de las muestras cumple los requerimientos del Codex alimentario turco y de las directivas de la Comisión Europea.Fil: Bakirdere, Sezgin. Universidad Técnica de Yıldız (Turquía)Fil: Yaroglu, Tolga. Universidad de Ankara (Turquía)Fil: Tirik, Nihan. Ondokuz Mayıs University (Turquía)Fil: Demiroz, Mehmet. Uludag University (Turquía)Fil: Karaca, Abdullah. Fırat University (Turquía

Determination of lead, cadmium and copper in roadside soil and plants in Elazig, Turkey

The concentrations of lead, cadmium and copper in roadside soil and plants in Elazig, Turkey were investigated. Soil samples were collected at distances of 0, 25 and 50 m from the roadside. The concentrations of lead, cadmium and copper were measured by Flame Atomic Absorption Spectrophotometry (FAAS). A slotted tube atom trap ( STAT) was used to increase the sensitivity of lead and cadmium in FAAS. Lead concentrations in soil samples varied from 1.3 to 45 mg kg(-1) while mean lead levels in plants ranged from 120 ng g(-1) for grape in point-4 to 866 ng g(-1) for apple leaves in point-2. Lead analyses showed that there was a considerable contamination in both soil and plants affected from traffic intensity. Overall level of Cd in soil samples lies between 78 and 527 ng/g while cadmium concentration in different vegetations varied in the range of 0.8-98.0 ng g(-1). Concentrations of copper in soil and plant samples were found in the range of 11.1-27.9 mg kg(-1) for soil and 0.8-5.6 mg kg(-1) for plants. Standard reference material (SRM) was used to find the accuracy of the results of soil analyses

Trace level determination of beryllium in natural and flavored mineral waters after pre-concentration using activated carbon

The concentrations of beryllium (Be) in natural and flavored mineral water samples were determined by flame atomic absorption spectrophotometer (FAAS) after pre-concentration based on the complexation of Be(+2) with a mixture of acetylacetone (pentane-2,4-dione) plus morin (3,5,7,2',4'-pentaoxyflavone) and adsorption on activated carbon. The adsorbed complex was eluted with 1.5 ml of 2.0 M HNO(3) and evaporated to dryness. After adding 1.5 ml of 2 M HNO(3) and centrifuging, Be in acid solution was determined by FAAS. To remove a number of metals present in water, EDTA was used as a chelating agent. Beryllium in mineral water samples was pre-concentrated by 500-fold, taking 750 ml as initial sample and 1.5 ml as the final volume. The relative standard deviations were sufficiently low for practical purposes and recoveries were up to 85%. Spiking experiments were performed in real samples to establish accuracy and recoveries. The limits of detection and quantification were 0.01 and 0.03 ng ml(-1), respectively. Twenty samples were analyzed for their beryllium content using optimum parameters. The highest concentration of beryllium was found to be 0.94 +/- 0.15 ng ml(-1) in a natural mineral water, while beryllium was not detected in five samples

Comparison of dry, wet, and microwave ashing methods for the determination of Al, Zn, and Fe in yogurt samples by atomic absorption spectrometry

Digestion methods such as dry and wet ashing and microwave oven were examined at various conditions to determine a rapid, reliable, and simple digestion procedure for yogurt. Digestion by microwave oven was found to be an excellent method in comparison with dry and wet ashing methods when only A1 and Zn in yogurt samples were determined. Iron in this matrix is not completely digested by the microwave oven method at the examined conditions. From the obtained results, yogurt can also be a good source of essential nutrients such as minerals in human diet, especially zinc. Aluminum concentrations in yogurt samples fermented in A1 containers were found to be significantly higher than in plastic containers. Al concentrations of yogurt taken from the bottom of the container were found to be higher than from the center and top of Al containers. The determinations of metals were carried out via an atomic absorption spectrophotometer using calibration curve and standard additions methods. Aluminum concentrations in yogurt samples produced in big production centers were found to be significantly higher than the other yogurt samples produced in-house when plastic containers were used

Determination of Zinc, Copper, Iron, and Manganese in Different Regions of Lamb Brain

The levels of zinc, copper, iron, and manganese were measured in the hippocampus, thalamus, gyrus cinguli, hypothalamus, and in the prefrontal, parietal, temporal, and occipital cortexes of lamb brain by flame atomic absorption spectrometry. Standard addition method was also applied to samples and it was observed that there was no matrix interference affecting the determination of elements interested. In the determination of Cu, a slotted tube atom trap was used to improve sensitivity. One-way analysis of variance was used for the statistical evaluation of the results for each element. Limit of detection results for Zn, Cu, Fe, and Mn were found to be 24, 4.5, 60, and 25 ng/mL, respectively. Region-specific differences were found for all elements interested. Mn concentration ranging from 0.29 +/- 0.04 to 0.61 +/- 0.04 mg/kg was found to be the lowest in all brain regions among the all elements interested

Speciation of Arsenic in Fish by High-Performance Liquid Chromatography-Inductively Coupled Plasma-Mass Spectrometry

Arsenic speciation in fish was performed using isocratic elution with cation exchange column high-performance liquid chromatography and inductively coupled plasma-mass spectrometry detection. The separation of arsenobetaine and dimethylarsinic acid was performed in 12 min. DOLT-4 dogfish liver and NIST RM-50 albacore tuna certified reference materials were used to evaluate the accuracy for the determination of total arsenic in fish. In addition, reference materials were analyzed for arsenobetaine and dimethylarsinic acid, although they were not certified for these analytes. The limits of detection for arsenic in arsenobetaine and dimethylarsinic acid were 0.20 and 0.33 ng/mL, and the limits of quantitation were 0.58 and 1.11 ng/mL, respectively. Total arsenic and arsenic species were determined in fish using the developed method. The predominant arsenic species was arsenobetaine; the measured concentrations were from 0.43 to 12.0 mg/kg arsenic as arsenobetaine. Dimethylarsinic acid concentrations were below the limit of quantitation. The relative standard deviations were between 3.36 and 10.49 for total arsenic and 3.51 and 9.30 for arsenobetaine

Magnetic Nanoparticle-Based Dispersive Solid-Phase Microextraction of Three UV Blockers Prior to Their Determination by HPLC-DAD

The need for proper handling of environmental samples is significant, owing to their environmental effects on both humans and animals, as well as their immediate surroundings. In the current study, magnetic nanoparticle-based dispersive solid-phase microextraction was combined with high-performance liquid chromatography using a diode array as the detector (HPLC-DAD) for both the separation and determination of three different UV blockers, namely octocrylene, ethylhexyl methoxycinnamate, and avobenzone. The optimum conditions for the extraction were found to be as follows: Stearic acid magnetic nanoparticles (20 mg) as the sorbent, acetonitrile (100 µL) as the eluent, as well as a sample pH of 2.50, adsorption and desorption time of 1.0 min, with a 3.0 mL sample volume. The limits of detection were as low as 0.05 µg mL−1. The coefficient of determination (R2) was above 0.9950, while the percentages of relative recoveries (%RR) were between 81.2 and 112% for the three UV blockers from the environmental water samples and sunscreen products