Evaluation of alginate and zein films as a carrier of natamycin to increase the shelf life of kashar cheese

The aim of this study was to develop alginate and zein films containing natamycin, a natural antifungal agent, in order to limit/prevent the mould growth on the surface of kashar cheeses. The films were prepared by casting, and characterized in terms of antimicrobial and mechanical properties (tensile strength, elongation-at-break, and elastic modulus), and their morphology was examined by scanning electron microscopy (SEM). Mechanical properties of the zein films were found to be weaker than the alginate films. SEM analysis indicated that alginate films have a more regular structure than zein films, and a more homogenous distribution was observed at lower concentrations of natamycin. The antifungal activities of both films increased as the natamycin concentration (100, 200, 500, 1000, 2000, and 4000 ppm) increased; however, alginate films exhibited relatively high antifungal activity. The effects of films on the shelf life of kashar cheeses inoculated with Aspergillus niger and Penicillium camemberti were investigated during their storage under refrigerator conditions for 45 days. At high-natamycin concentrations, zein films showed higher antifungal activity against both fungi at the end of the storage period.     

Improved interfacial adhesion with the help of functional polyhedral oligomeric silsesquioxanes in silicone rubber/rayon fiber composites: Physical,mechanical, thermal,and morphological properties

The aim of this article is to improve the interfacial adhesion between silicone rubber (SR) and Rayon fiber by the help of functional hybrid POSS nanoparticles. Two POSS types were compared, octavinyl-POSS (O-POSS) and methacryl-POSS (M-POSS), having reactive  CC double bonds that can impart in peroxide crosslinking. O-POSS is nonpolar, whereas M-POSS is polar and is able to make H-bond with Rayon fibers. POSS type and their concentrations were examined as the experimental parameters. H-adhesion tests indicated that both POSS types enhanced the adhesion of SR composites to Rayon fibers compared with control recipe. Specifically, slightly higher values were obtained with the use of M-POSS. It was observed that both O-POSS and M-POSS slowed down the curing rate but increased the degree of crosslinking. The cure extent of O-POSS containing composites was found to be higher than that of M-POSS containing ones. Thermal gravimetric analyses revealed that thermal stability of SR composites was significantly improved by the addition of POSS particles. Higher char yield and degradation temperatures were obtained with O-POSS at higher loadings with respect to M-POSS. The POSS distribution at lower loading levels was found to be homogenous for both POSS types as observed from scanning electron microscope and transmission electron microscope.     

Investigation of hybrid‐capacitor properties of ruthenium complexes

Ru complexes were successfully produced, and their structural properties were investigated using FTIR, Raman, and single crystal XRD patterns. The HOMO, LUMO, Eg, and electronic surface potential (ESP) values of the molecules were calculated by a Gaussian program. The complexes were used for producing hybrid capacitor cells as electrode materials. According to electrochemical analysis, complex 2 showed the best CV graph between ?1 V and +1 V and had the highest current value and hysteresis area when compared with the other complexes. The performance analysis and the capacity fade of the cells were investigated. The first capacity values of the complexes were 57.5, 22.1, 16.9, and 0.0021 F/g for complexes 1 , 2 , 3 , and 4 , respectively. The capacitive mechanism of the cells as relates to molecular interactions was also investigated. We suggested that the ESP values of the molecules were directly related to the capacitive performance of the cells. In addition to this, the best cycling performance was obtained for complex 2, which has the lowest Eg value among the complexes. We speculate that the charged regions on the complex materials have a crucial role in the increasing the capacitance of the cells.     

Biochemical characterization of a semi-purified aspartic protease from sea catfish Bagre panamensis with milk-clotting activity

Food Science and Biotechnology - Pepsin from stomach of Bagre panamensis was semi-purified and biochemically characterized. The acid proteolytic activity and purification fold were...     

Alcoholism detection based on Hu moment invariants of event-related potentials

Diagnostic efforts to identify alcoholism are frequently subjective; however, recent technological advances have allowed the automated assessment of objective signals. To improve the performance of the automated classification of patients with alcohol dependence (AD) and controls, we analyzed features of event-related potentials (ERPs) in 72 subjects with AD and 42 controls while the subjects underwent three different visual oddball tasks. In addition to such commonly used morphological features (MFs) as time-domain amplitude and latency components as well as discrete wavelet transform coefficient entropies (WEs), we analyzed Hu moment invariants (HMIs) in this study. Smaller P3 and P2 amplitudes, longer latencies, lower WE values, and lower HMI values were observed for AD subjects relative to those observed for controls. We used a Naïve Bayes algorithm to compare classification accuracies among MFs, WEs, HMIs, combinations of MFs/WEs, and combinations of all three characteristics. We found that HMIs improved the classification accuracy by 17%. Our findings demonstrated that a combined feature analysis of ERPs obtained during a visual oddball task can be a useful and discriminative tool for diagnostic purposes in alcoholism and that HMIs show promise for improving the objective diagnosis of alcoholism and similar diseases.