Role of curcumin in the conversion of asparagine into acrylamide during heating

This study aimed to investigate the ability of curcumin to convert asparagine into acrylamide during heating at different temperatures. Binary and ternary model systems of asparagine–curcumin and asparagine–curcumin–fructose were used to determine the role of curcumin on acrylamide formation in competitive and uncompetitive reaction conditions. The results indicated that curcumin could potentially contribute to acrylamide formation under long-term heating conditions as long as asparagine was present in the medium. The amount of acrylamide formed in the ternary system was slightly higher than in the binary system during heating (p < 0.05), because of the higher concentrations of carbonyl compounds initially available. The kinetic trends were similar in both model systems evidencing that fructose reacted with asparagine more rapidly than curcumin. The data reveal that acrylamide formation in the temperature range of 150–200°C obeys Arrhenius law with activation energy of 79.1 kJ/mole. Data of this work showed the possibility that antioxidants having a carbonyl compound can react directly with ASN leading to acrylamide. The addition of antioxidants to foods may increase the formation of acrylamide upon long-term heating if free sugar concentration is low and ASN concentration is relatively high.     

On-line preconcentration/determination of zinc from water,biological and food samples using synthesized chelating resin and flame atomic absorption spectrometry

An on-line flow injection pre-concentration-flame atomic absorption spectrometry method was developed to determine trace zinc in water (tap, dam, and well water), biological (hair and nail), and liver samples. As a solid phase extractant, a synthesized new chelating resin, poly(2-thiozylmethacrylamide-co-divinylbenzene-co-2-acrylamido-2-methyl-1-propane sulfonic acid) was used. The resin was characterized by Fourier transform infrared spectroscopy, elemental analysis, and surface area by nitrogen sorption. A pre-concentration factor of 40-fold for a sample volume of 12.6 mL was obtained by using the time-based technique. The detection limit for the pre-concentration method was found to be 2.2 μg L^?1. The precision (as RSD,%) for 10 replicate determinations at the 0.04 μg mL^?1 Zn concentration was 1.2%. The calibration graph using the pre-concentration system for zinc was linear with a correlation coefficient of 0.998 in the concentration range from 0.005 to 0.05 μg mL^?1. The applicability and accuracy of the developed method were estimated by the analysis spiked water, biological, liver samples (83–105%), and also certified reference material TMDA-70 (fortified lake water) and SPS-WW1 Batch 111-Wastewater. The results were in agreement with the certified values.     

Molecularly imprinted cryogels for human interferon‐alpha purification from human gingival fibroblast culture

Interferons are important proteins for the immune system because of their antiviral, anti‐proliferating and immunomodulatory activities. Therapeutic value of these proteins against certain types of tumors caused interest and investigations aimed to obtain highly purified interferons. Molecular imprinting is an efficient method for purification with high selectivity, specificity and good reproducibility. In this study, we utilized advantages of molecular imprinting technique for the purification of interferon from human gingival fibroblast culture. For this purpose, interferon α‐2b imprinted poly(hydroxyethyl methacrylate) cryogel (hIFN‐α‐MIP) was prepared. Optimum adsorption conditions were determined, and maximum adsorption capacity of hIFN‐α‐MIP cryogel was found as 254.8 × 10⁴ IU/g from aqueous solution. All interferon measurements are expressed as International Unit (IU), which is a unit measurement used to quantify biologically active substances like interferon based on their biological activity or effect. Selectivity experiments were performed using competitive proteins and repeated adsorption–desorption studies showed that the adsorption capacity maintained almost at a constant value after ten cycles. For the purification of interferon from human gingival fibroblast culture, fast protein liquid chromatography was used and the specific activity of the purified interferon α‐2b on HeLa cell line was found between the values 3.45 × 10⁸ IU/mg and 3.75 × 10⁸ IU/mg. The results are promising, and the molecular imprinting technique is effective for the purification of interferon α‐2b. Copyright © 2013 John Wiley & Sons, Ltd.     

Chemical Composition and Biological Activity of Centaurea baseri: New Species from Turkey

The genus Centaurea L. is one of the largest and important genera of Asteraceae family. Centaurea species have been widely used as herbal remedies in folk medicine for their antidandruff, antidiarrheic, antirheumatic, anti‐inflammatory, choleretic, diuretic, digestive, stomachic, astringent, antipyretic, cytotoxic, and antibacterial properties. Centaurea baseri Kose & Alan is a recently described local endemic species in Turkey and this is the first study on the chemical composition and bioactivity of its hydrodistilled essential oil and the crude extract. According to chromatospectral analysis, hexadecanoic acid (42.3%), nonacosane (8.2%), and heptacosane (8.0%) were the main compounds of the essential oil, while 16 compounds were determined in the MeOH extract using LC/MS. Furthermore, antimicrobial, antioxidant, and cytotoxic effects of the essential oil and the extract were evaluated in comparison with the standard agents. The extract showed strong antifungal effect against Candida utilis at the concentration of 60 μg/ml (MIC) where the EO showed growth inhibition at the concentration of 47.00 μg/ml (MIC) against pathogen Bacillus cereus. Both the essential oil and the extract did not show any selective antioxidant properties. The extract showed remarkably selective cytotoxic properties against MCF‐7, PANC‐1, A549, and C6 glioma cells.     

Factors predicting treatment adherence in patients with adult attention-deficit/hyperactivity disorder: a preliminary study

This study aimed to elicit patient- and treatment-related factors that can potentially predict treatment adherence in adult ADHD. Subjects who were over 18 and received a diagnosis of ADHD were included in the study. Chart review data of 102 subjects regarding demographics, medications, comorbidities, concomitant medications and domains of functional impairment were collected, and predictors were assessed using a binominal logistical regression model. One hundred and two patients (78.4 % male) with a mean age of 28.8 (SD = 9.8, range = 18–55) years were enrolled in the study. Childhood diagnosis of ADHD, agents used for treatment (MPH or atomoxetine), individual domains of dysfunction and use of additional psychotropic drugs were not found to be related to treatment adherence. Patients with a university education and those referred for family history of ADHD were more likely to adhere to treatment (p = 0.05 and 0.03, respectively). On the other hand, reasons for referral other than ADHD were significantly more frequently related to non-adherence (p = 0.02). Treatment noncompliance remains a significant problem despite therapeutic effects of medications. Identification of predictors of non-adherence can lead to heightened awareness of special populations at risk. We have found that prior awareness on ADHD (via past history/media/friends) leading to self/clinician referral to rule out ADHD and pervasiveness of symptoms across functional domains led to better compliance in our sample. Future research with prospective design utilizing objective tools for adherence is required.