Improving olive oil quality with double protection: Destoning and malaxation in nitrogen atmosphere

Effect of destoning and malaxation in nitrogen atmosphere on oxidative stability, fatty acid and sterol composition of extra virgin olive oil (EVOO) were investigated in industrial scale. Olives of ‘Edremit yaglik’ cultivar were processed with a two phase centrifugal system with or without stones, in nitrogen or air atmosphere. Results have shown that either N₂ flush or destoning did not make any contribution to the sterol and fatty acid composition. Malaxation in nitrogen atmosphere extended induction time, raised phenolic, tocopherol contents and antioxidant potential of oils. Destoning also increased oxidative stability but lowered carotenoid and chlorophyll contents of oils. Among all treatments, the combined effect of destoning and malaxation in nitrogen atmosphere achieved the production of EVOO with the highest quality.     

Monitoring of seed composition of prickly pear (Opuntia ficus‐indica L) fruits during maturation period

Prickly pear fruit seeds were subjected to a range of chemical analyses during their 15 week maturation period. Seeds contained on average 71.5 g kg^?1 dry matter, 61.9 g kg^?1 crude oil, 9.4 g kg^?1 protein, 507.4 g kg^?1 crude fibre, 12.3 g kg^?1 ash and 409.0 g kg^?1 carbohydrate. The fatty acid composition of prickly pear seed oil consisted of 1.3–1.9 g kg^?1 myristic (14:0), 132.1–156.0 g kg^?1 palmitic (16:0), 14.4–18.5 g kg^?1 palmitoleic (16:1), 33.1–47.9 g kg^?1 stearic (18:0), 210.5–256.0 g kg^?1 oleic (18:1), 522.5–577.6 g kg^?1 linoleic (18:2), 2.9–9.7 g kg^?1 linolenic (18:3), 4.2–6.6 g kg^?1 arachidic (20:0) and 2.1–3.0 g kg^?1 behenic (22:0) acids, which is comparable with that of corn oil. No statistical difference in seed weight ratio was determined during the maturation period, whereas changes in the saturated fatty acids of the seed oil were observed. From this study it can be concluded that the seeds of prickly pear are suitable as animal feed. Copyright © 2003 Society of Chemical Industry     

Efficient mineralization of sugar industry wastewater by catalytic wet air oxidation as an eco-friendly method and its kinetic modelling

In this study, catalytic wet air oxidation using lanthanum cobalt oxide (LaCoO₃) as catalyst was employed for the efficient treatment of synthetic sugar industry wastewater in a single process. A parametric study was performed to determine the optimum conditions. The results showed that reaction temperature and theoretical air percentage were the most effective parameters. Sugar derivatives were almost completely destroyed at the optimum conditions and total organic carbon (TOC) and chemical oxygen demand (COD) removals were determined as 91% and 87%, respectively, indicating a high mineralization degree, which was the main goal of advanced oxidation. The reaction kinetics were investigated by pseudo-homogeneous and heterogeneous models based on two different parameters: sucrose and TOC concentration. The degree of fit showed that the reaction order was determined as two for the pseudo-homogeneous approach. According to the surface concentration calculations for heterogeneous models, the presence of mass transfer limitations was only observed for oxygen as gas reactant. All heterogeneous models also fitted the reaction rate data accurately, but the Mars–van Krevelen was the selected model for sucrose and TOC oxidation with the best fit.     

A comparison of the transmission through butt and overlap gaps

This paper compares the transmission through electrically thin butt and overlap gaps. It is shown that in the limit as the gap widths approaches zero, the transmissions are identical and the transmitted power can be minimized by choosing the gap depths as a quarter wavelength plus an integer number of half wavelengths     

Activity Comparison of Different Solid Acid Catalysts in Etherification of Glycerol with tert-Butyl Alcohol in Flow and Batch Reactors

In the presented work, etherification of glycerol with TBA was investigated in a continuous flow and also in a batch reactor using nine different commercial solid acid catalysts, namely Amberlyst-15, Amberlyst-36, Amberlyst-35, Amberlyst-16, Relite EXC8D, Lewatit K2629, H-Beta, H-Mordenite and Nafion SAC-13. Results proved the advantages of flow reactor to achieve quite high glycerol conversion values in very short residence times, due to efficient contact of reactants with the solid catalyst, which was caused by higher catalyst to reactant ratio within the reactor. Results of batch reactor experiments obtained in the temperature range of 80–200 °C proved the importance of operating temperature on the catalytic performance of these materials. Amberlyst-15, which has the highest Brønsted acidity, gave the highest glycerol conversion at 90–100 °C. However, this material is unstable at temperatures higher than 110 °C. Performances of Amberlyst-36 and Relite EXC8D were the best in the range of 110–150 °C, which started to become unstable at 150 °C. Although the catalytic performance of Nafion-SAC-13 was not as good as Amberlyst type resins at temperatures up to 150 °C, its thermal stability was higher and could be used up to 200 °C. Although Brønsted acidity was the most important property of these materials in the etherification reaction of glycerol, results also proved the importance of diffusion resistance on the observed conversion values, which limited the penetration of glycerol to the active acid sites, especially in the catalysts with smaller pore diameters and at lower temperatures. Increased significance of swelling at higher temperatures, especially with Amberlyst-36 which had lower cross-linking in its structure and less rigidity, contributed to the penetration of the reactants to the active sites. Water produced during the etherification reaction was also shown to cause deactivation of the catalysts by reversible adsorption on the acid sites.     

Nuclear AgNOR protein enhancement in nucleoplasms of peripheral blood lymphocytes of babies/children with down syndrome

Down syndrome (DS) is one of the most common chromosomal disorders. The factors contributing to the mental retardation together with other defects in this syndrome have not been fully explained. Individuals with DS have extra rRNA gene family since they carry an extra chromosome 21. The few reports available are on the relationship between the nucleolus organizer regions (NORs) and DS phenotype. The in vivo regulation of NORs expression on the extra chromosome 21 is not completely understood. Previous studies have shown that nucleoli of lymphocytes from infants (mostly neonates) with DS contain more in vivo and in vitro nucleolar AgNOR proteins when compared with healthy infants. The objective of this study is to compare the in vivo nuclear AgNOR protein level in nucleoplasms (also called as karyoplasm) of nonstimulated peripheral blood lymphocytes from babies/children with DS and healthy controls. Peripheral blood samples obtained from 20 babies/children with DS and 20 matched healthy controls were smeared on clean glass slides and then AgNOR staining was performed. The AgNOR protein level in nucleoplasms of lymphocytes from both groups was calculated using a computer program. Nearly 100 interphase nuclei per individual were analysed. Average nuclear AgNOR protein levels in nucleoplasms of lymphocytes from babies/children with DS were found to be significantly higher than those of the controls (P < 0.001). On the basis of our present results, we propose that the increase of nuclear AgNOR protein in in vivo conditions may contribute to the formation of DS phenotypes. Microsc. Res. Tech. 79:133–139, 2016. © 2016 Wiley Periodicals, Inc.     

Boron removal by liquid‐phase polymer‐based retention technique using poly(glycidyl methacrylate N‐methyl D‐glucamine)

The removal of boron was analyzed by liquid‐phase polymer based retention (LPR) technique using washing and enrichment method. The extracting reagents were water‐soluble polymers (WSPs) containing quaternary ammonium salts and N‐methyl‐D ‐glucamine (NMG) groups. The removal experiments of boron using the washing method were conducted at 1 bar of pressure by varying pH, polymer:boron molar ratio, and concentrations of interfering ions (chloride and sulfate). The results showed higher retention capacity for boron (60%) at pH 10 with the polymer containing NMG group. The optimal polymer:boron molar ratio was 40 : 1. Selectivity experiments showed that the presence of interfering ions did not affect the boron removal capacity. The maximal boron retention capacity was determined by the enrichment method, obtaining a value of 12 mg B/g‐polymer. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Cadmium removal out of human plasma using ion-imprinted beads in a magnetic column

The aim of this study is to utilize ion-imprinted magnetic beads in the selective removal of Cd²⁺ ions out of human plasma overdosed with Cd²⁺ ions. The Cd²⁺ imprinted magnetic poly(HEMA-MAC) (mPHEMAC-Cd²⁺) beads were produced by suspension polymerization in the presence of magnetite Fe₃O₄ in a nano-powder form. The template Cd²⁺ ions could be reversibly detached from the matrix to form mPHEMAC-Cd²⁺ beads using 0.1 M thiourea solution. The specific surface area of the mPHEMAC-Cd²⁺ beads was found to be 24.7 m²/g. The MAC and Fe₃O₄ contents of the mPHEMAC-Cd²⁺ beads were found to be 41.8 µmol/g polymer and 8.2% on the average. The Cd²⁺ adsorption capacity of mPHEMAC-Cd²⁺ columns decreased drastically from 48.8 µmol/g to 20.0 µmol/g as the flow rate is increased from 0.50 ml/min to 3.0 ml/min. The maximum adsorption capacity of the mPHEMAC-Cd²⁺ beads was determined to be 48.8 µmol Cd²⁺/g on the average. The relative selectivity coefficients of the mPHEMAC beads for Cd²⁺/Pb²⁺ and Cd²⁺/Zn²⁺ were 22.6 and 160.7 times greater than those of the non-imprinted magnetic PHEMAC (mPHEMAC) beads, respectively. The mPHEMAC-Cd²⁺ beads are reusable for many times with no significant decrease in their adsorption capacities.