Development and application of a new multiplex real‐time PCR assay for simultaneous identification of Brucella melitensis,Cronobacter sakazakii and Listeria monocytogenes in raw milk and cheese

Brucella melitensis, Cronobacter sakazakii and Listeria monocytogenes are important foodborne pathogens in milk and milk products, which are responsible for a variety of diseases that pose serious hazards to public health and food safety. The objective of this study was to develop a novel multiplex RTi‐PCR for the detection of B. melitensis, C. sakazakii and L. monocytogenes and to characterise the potential risk of these pathogens in raw milk and cheese. The raw milk (n = 25) and cheese samples (n = 20) were analysed by multiplex RTi‐PCR assay and detected for quantification of the three pathogens. In this study, B. melitensis, C. sakazakii and L. monocytogenes were simultaneously identified using BMEII0466, mms operon and hly as target genes, respectively. The multiplex RTi‐PCR assay that was developed showed good sensitivity and selectivity for the pathogenic microorganisms (r² = 0.986–0.997). Multiplex RTi‐PCR results showed that most of the samples were contaminated with the pathogens screened.     

Discovery and Optimization of Piperazine Urea Derivatives as Soluble Epoxide Hydrolase (sEH) Inhibitors

Soluble epoxide hydrolase (sEH) is implicated as a potential therapeutic target for inflammation-related pathologies in the context of cardiovascular, central nervous system and metabolic diseases. In our search for novel sEH inhibitors, we designed and synthesized novel analogs of the piperazine urea derivative 4 , a previously discovered dual microsomal prostaglandin E₂ synthase-1 (mPGES-1)/soluble epoxide hydrolase (sEH) inhibitor, to evaluate their potential as sEH inhibitors. We identified two 1,3,4-oxadiazol-5-one and -thione congeners (compounds 19 and 20 ), which demonstrated selective sEH inhibition with IC₅₀ values in the two-digit nanomolar range (42 and 56 nM, respectively). These results suggest that the installation of terminal 1,3,4-oxadiazol-5-one/thione functions to the benzyl end can be regarded as a promising secondary pharmacophore in addition to the urea group for sEH inhibition, and compound 19 can be regarded as novel lead structure for further optimization of improved sEH inhibitors.     

Dielectric properties of Jordanian oil shales

Microwave heating has been suggested by various authors as a suitable technology for extraction of organic material from oil shales. However, one of the limiting factors in the development of this technology is a lack of accurate dielectric property data for design purposes. In this study the dielectric behaviour of El-lajun oil shale is quantified. The dielectric constant and loss factor of El-lajun oil shale were measured at 2470 and 912 MHz using the cavity perturbation technique. The effects of organic content, temperature, and moisture content on the microwave heating efficiency were quantified. Coaxial probe technique was also employed to study the effect of frequency on dielectric properties of oil shale. Generally, it was found that all samples were of low dielectric loss at room temperature with the imaginary part of permittivity falling significantly after the moisture was removed. This suggests that the major contribution in the dielectric loss is due to the presence of free and/or interlayer water. It was found that both the real and imaginary part of complex permittivity increased with a rise in temperature from 20 up to 80 °C, then dropped significantly at about 100 °C before staying approximately constant up to a temperature of about 480 °C. From this temperature both the real and imaginary parts of complex permittivity increased sharply with further increase in temperature. An attempt was also made to correlate the dielectric properties of the bulk shale sample with the organic content. However, no correlation between dielectric properties and organic matter content was found.     

Calix[4]arene Polyamine Triazoles: Synthesis,Aggregation and DNA Binding

Artificial gene delivery systems are in great demand from both scientific and practical biomedical points of view. In this paper, we present the synthesis of a new click chemistry calix[4]arene precursor with free lower rim and new water-soluble calixarene triazoles with 12 amino-groups on the upper rim (one with free phenol hydroxyl groups and two another containing four butyl or tetradecyl fragments). Aggregation in the series of amino-triazole calixarenes of different lipophilicity (calixarene with free phenol hydroxyl groups or butyl and tetradecyl fragments on the lower rim) was studied using dynamic light scattering and fluorescent pyrene probe. It was found that calix[4]arene with a free lower rim, like alkyl-substituted butyl calix[4]arene, forms stable submicron aggregates 150–200 nm in size, while the more lipophilic tetradecyl –substituted calix[4]arene forms micellar aggregates19 nm in size. Using UV-Vis spectroscopy, fluorimetry and CD, it was shown that amino-triazole calix[4]arenes bind to calf thymus DNA by classical intercalation. According to DLS and TEM data, all studied macrocycles cause significant DNA compaction, forming stable nanoparticles 50–20 nm in size. Among all studied calix[4]arenes the most lipophilic tetradecyl one proved to be the best for both binding and compaction of DNA.     

The effect of D‐glucose on milk clotting activity of Mucor miehei in a chemostat with biomass retention

In this study microbial production of rennin from a commercial strain of Mucor miehei (NRRL 3420) has been accomplished in a continuously fed fermenter. The effects of feed D ‐glucose concentration (2.5–30 g dm⁻³) on milk clotting activity and on other system variables were investigated at optimum mixing and dilution rates of 400 rpm and 0.0052 h⁻¹, respectively, without pH control. Maximum milk clotting activity (1.24 IU cm⁻³) occurred when the feed D ‐glucose concentration was 7.5 g dm⁻³. Enzyme production continued for 500 h, producing a total milk clotting activity of 10 230 IU. At the maximum milk clotting activity point, total protein concentration, milk clotting and proteolytic activities were analysed and compared with those of a commercial rennet. The ratio of milk clotting activity to proteolytic activity, and specific milk clotting activity were determined as 1.55 × 10⁻³ IU PU⁻¹ and 5.28 IU mg⁻¹ medium protein, respectively, denoting similar characteristics to a commercial rennet after concentration of the fermentation medium. © 1999 Society of Chemical Industry     

Treatment of paint manufacturing wastewater by electrocoagulation

Treatability of paint manufacturing wastewater (PMW) by electrocoagulation (EC) process was investigated. Effects of operating parameters for the EC process such as electrode type (Al or Fe), initial pH (2–10), current density (5–80 A/m²) and operating time (0–50 min) were evaluated for optimum operating conditions. The highest removal efficiencies for COD and TOC in PMW were obtained with 93% and 88% for Fe and 94% and 89% for Al electrodes at the optimum conditions (35 A/m², 15 min and pH 6.95). Operating costs for removal of PMW at the optimum conditions were calculated for Fe and Al electrodes as 0.187 €/m³ and 0.129 €/m³. Toxicity test was carried out to obtain information about toxic effect of the raw and treated wastewaters at optimum operating conditions. The samples measured by respirometric method contained hardly toxicities. Performance of Al electrode was better than that of Fe electrode in terms of removal efficiency and operating cost.     

Nutritional quality of protein in the leaves of eleven Asphodeline species (Liliaceae) from Turkey

The nutritional quality of the protein in the leaves of 11 Asphodeline (Liliaceae) species was investigated by the determination of the amino acid composition and calculation of several nutritional parameters. The average protein content was 4.7% and ranged from 2.5% in Asphodeline damascena ssp. rugosa to 8.2% in A. turcica. The most abundant essential amino acids were Thr (5.7%), Val (6.0%), Ile (4.7%), and Trp (2.1%). The amino acid composition of Asphodeline peshmeniana was well equilibrated according to Food and Agriculture Organisation standards, but Lys and sulphur amino acids were at limiting concentrations in all the other taxa. Determination of the protein efficiency ratio and biological value revealed that the protein in the leaves of Asphodeline species is of high nutritional quality. Hence, the Asphodeline leaves that are typically used in Turkey for the preparation of salads, represent a good source of protein with high levels of several essential amino acids and a good nutritional value. Analysis of the similarity based on the amino acid composition indicated the existence of different clusters that are consistent with the taxonomical classification, area of distribution, and morphological similarities of the Asphodeline species.     

Sorption and desorption behaviours of 2,4‐D and glyphosate in calcareous soil from Antalya,Turkey

2,4‐Dichlorophenoxyl acetic acid (2,4‐D) and glyphosate are used extensively as a herbicide in vicinity of Antalya, Turkey. Laboratory batch experiments were conducted to investigate the sorption isotherm and sorption‐desorption characteristics of 2,4‐D and glyphosate. Results indicated that degree of sorption of glyphosate was approximately 50 times higher than 2,4‐D (K_d= 34.43 vs. 0.66 L/Kg). The sorption of 2,4‐D and glyphosate was described by linear and rate‐limited processes for soil. Organic carbon content was most likely responsible for sorption behaviour of 2,4‐D and glyphosate. The rapid desorption can be attributed to soft carbon fraction (humic/fluvic acid and lipids) whereas slower desorption can be responsible by hard carbon fraction (black carbon, kerogen) of soils that led to chemically nonideal behaviour (hysteresis). Sorption of 2,4‐D was low due to most likely deactivation of organic carbon surfaces by excess carbonate fraction, whereas strong binding of glyphosate onto organic carbon causing high sorption behaviour.