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In this study, 341 Bacillus sp. strains were isolated from agricultural soils of Turkey. The potent extracellular lipase producer was selected. It was identified by 16S rRNA, named as Bacillus cereus ATA179. Optimal nutritional and physical parameters for lipase production were determined. Sucrose as the carbon source, (NH4)2HPO4 as the nitrogen source, CaCl2 as the metal ion were obtained. The best results of physical parameters were stated at 45°C, pH 7.0, shaking rate 50 rpm, inoculation amount 7% and inoculum age 24 h. ATA179 strain showed a 51% increase in enzyme production in the modified medium created by optimizing nutritional and physical conditions. Optimum pH value and temperature were found as 6.0 and 55 °C, respectively. CaCl2, Tween 20, Triton X-100 had an activating effect on enzyme activity. Vmax and Km kinetic values were found as 18.28 U/mL and 0.11 mM, respectively. The molecular weight was determined as 47 kDa. Lipase was found to be stable up to 75 days at -20 °C. The potential of the enzyme in detergent industry was also investigated. It was not affected by detergent additives, but was found to be effective in removing oils from contaminated fabrics. This new lipase may have potential to be used in detergent industry. [ABSTRACT FROM AUTHOR]

In this study, it was aimed to determine the ability to produce protease enzyme of Thermomonas haemolytica isolated from geothermal Nenehatun hot spring in Turkey and utilization of this enzyme in the detergent industry to remove protein stains. The protease-producing strains were screened from hot springs, and a potential strain was identified as T. haemolytica according to morphological, physiological and biochemical characteristics and sequence of 16S rRNA gene. Maximum protease activity was observed at 55 °C and pH 9.0 at 72 h of incubation. Activity was very stable between 50 and 65 °C and pH 8.0–10.0, respectively. The enzyme activity was significantly inhibited by PMSF and partly inhibited by EDTA, EGTA, SDS, and urea. Some divalent metal ions such as Ca2+, Mg2+, and Mn2+ increased the enzyme activity, while Zn2+ and Cu2+ decreased. Michaelis–Menten constant (Km) and maximum velocity (Vmax) values were calculated by Lineweaver–Burk plot as 125 EU/ml and 1262 mg/ml, respectively. The biochemical characterization of the protease obtained from T. haemolytica was performed and applied on the blood and grass-stained fabrics with detergent to evaluate the stain removal performance of the enzyme. It was observed that the application of detergent with enzyme was more effective than the detergent without enzyme to clean up the stained fabrics. This is the first report of characterization of the protease of T. haemolytica. According to results obtained from this study, this new strain is a promising candidate for industrial applications in production of detergent. [ABSTRACT FROM AUTHOR]

Lead, cadmium, nickel, manganese, cobalt and copper contents of some play dough, face and finger paint samples were determined by using a new solid phase extraction method which has been developed by using multi-walled carbon nanotube with patent blue (V) sodium salt to selectively separate and preconcentrate these metal ions. Flame atomic absorption spectrometry was used to determine the metal ions. Analytical parameters affecting the complex formation and solid phase extraction performance such as pH, the amount of ligand and volume of sample solution were investigated. The recoveries of the studied metal ions were not affected by the foreign ions. Analytes were recovered quantitatively at pH 5.5 and with a nitric acid of 2 mol L −1 as eluent. Analysis of a certified reference material was performed to validate the method before applying it to determine the metal ions in the real samples. Detection limits were found to be as Pb(II): 7.71 μg L −1 , Cu(II): 1.43 μg L −1 , Cd(III): 0.21 μg L −1 , Mn(II): 0.47 μg L −1 , Ni(II): 3.52 μg L −1 and Co(II): 1.96 μg L −1 . [ABSTRACT FROM AUTHOR]

Abstract: Results are presented for the cathodoluminescence (CL), radioluminescence (RL) and thermoluminescence (TL) of jade from Turkey. Jade samples show broad band luminescence from green to red, which, using lifetime-resolved CL, reveals seven overlapping emissions, of which two are dominant. Green emission obtained using spatially resolved CL was associated with Mn2+ and emission bands centered near at 480 and 530nm were attributed to 3P0–3H4 and 1D2–3H4 transitions of Pr3+, respectively. Different shifts of the peak-wavelengths for 326 and 565nm were observed with varying jade compositions. The incorporation of the larger K ion causes non-linear variations of the cell dimensions and therefore changes in the FeO band distance. We suggest that stress of the jade structure can be linked to the luminescence emission at 326nm. Raman spectra have also been recorded in order to provide an unequivocal identification of the type of jade. The mechanism for the luminescence of the jade is considered. [Copyright &y& Elsevier]

Abstract: Copper impregnated Cu@Al-PILCs, silver impregnated Ag@Al-PILCs and copper aluminum mixed Cu/Al-PILCs were prepared using a bentonite sample from the Hançılı region, Turkey. Incorporation of the Cu2+ or Ag+ ions forming CuO and Ag2O after calcination at 573K decreased the basal spacing of 1.85nm for Al-PILC by approximately 0.35nm. The specific BET surface area and mesopore+micropore volumes measured by 77K nitrogen adsorption after calcination at 573K decreased from 236m2 g−1 and 0.174cm3 g−1 to 174m2 g−1 and 0.172cm3 g−1 by Cu2+ impregnation and 171m2 g−1 and 0.168cm3 g−1 by Ag+ impregnation, while the values for Cu/Al-PILC were 209m2 g−1 and 0.184cm3 g−1. The micropore volume of all samples was about 20% of the total pore volume. The average Barrett–Joyner–Halenda (BJH) mesopore and Horvath–Kawazoe (HK) micropore dimensions were within 3.5–3.9nm and 0.44–0.48nm, respectively. Structural properties estimated from the Dubinin–Radushkevich (DR) method by using the nitrogen adsorption data were higher than those derived from the carbon dioxide adsorption data. SEM images indicated that Cu2+ incorporation increased the mesopore volume of the Al-PILC. [ABSTRACT FROM AUTHOR]

Abstract: A simple and effective method is presented for the separation and preconcentration of Th(IV), Ti(IV), Fe(III), Pb(II) and Cr(III) by solid phase extraction on 2-nitroso-1-naphthol impregnated MCI GEL CHP20P resin prior to their inductively coupled plasma-mass spectrometric determinations. The influence of analytical parameters including pH of the aqueous solution, flow rates of sample and eluent solutions and sample volume on the quantitative recoveries of analyte ions was investigated. Matrix effects caused by the presence of alkali, earth alkali and some metal ions in the analyzed solutions were investigated. The presented solid phase extraction method was applied to BCR-144R Sewage Sludge (domestic origin), BCR-141R Calcareous Loam Soil, NIST 1568a Rice Flour and NIST 1577b Bovine Liver certified reference materials (CRMs) for the determination of analyte ions and the results were in good agreement with the certified values. The separation procedure presented was also applied to the various natural water samples collected from Turkey with satisfactory results. [Copyright &y& Elsevier]