A Fast and Validated Method for the Determination of Malondialdehyde in Fish Liver Using High‐Performance Liquid Chromatography with a Photodiode Array Detector

Malondialdehyde (MDA) is a biomarker of lipid peroxidation and is present in foods and biological samples such as plasma. A high‐performance liquid chromatography (HPLC) method was applied to determine MDA in fish liver samples after derivatization with 2,4‐dinitrophenylhydrazine (DNPH) using a ODS2 column (10 cm × 4.6 mm, 3 μm) and a photodiode array detector. The mobile phase consisted of 0.2% acetic acid (v/v) in distilled water and acetonitrile (42:58, v/v). The present method was validated in terms of linearity, lower limit of quantification, lower limit of detection, precision, accuracy, recovery, and stability of MDA according to U.S. Food and Drug Administration (FDA) guidelines. The limit of quantification of MDA was 0.39 μmol/L, which is comparable to other methods. The recovery of the spiked MDA liver samples was in the range of 92.4% to 104.2%. This newly modified HPLC method is specific, sensitive, and accurate and allows the analysis of MDA within 4 min in fish liver but also in other tissues and plasma.     

Effect of corn‐zein coating on the mechanical properties of polypropylene packaging films

In this study, a novel film structure of corn zein coated on polypropylene (PP) synthetic films for food packaging applications was developed, and the mechanical properties of the resulting coated film, as affected by the coating formulation, were investigated. Composite structures of PP films coated with corn zein were obtained through a simple solvent casting method. Different amounts of corn zein (5 and 15%) were dissolved in 70 and 95% aqueous ethanol solution at 50°C. Solutions of corn zein plasticized with poly(ethylene glycol) and glycerol (GLY) at various levels (20 and 50%) were applied on corona‐discharge‐treated PP. A statistical analysis based on full factorial design was performed to examine the influence of the coating formulation on the final properties of the corn‐zein‐coated PP films. A significant (p < 0.05) improvement in the coated film's mechanical properties was observed compared to those of the uncoated PP. The effect of the plasticization of the coating solutions was also quite significant. In general, GLY provided better improvements in the mechanical properties of the corn‐zein‐coated PP films. The statistical analysis of the results showed that the corn‐zein and plasticizer concentrations and plasticizer type used in the coating formulations were more effective parameters and had significant effects on the mechanical behavior of the coated PP films. In conclusion, corn‐zein coatings could have potential as alternatives to conventional synthetic polymers used in composite multilayer structures for food packaging applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

A Comparative Assessment of Nutritional Composition,Total Phenolic,Total Flavonoid,Antioxidant Capacity,and Antioxidant Vitamins of Two Types of Malaysian Underutilized Fruits (Averrhoa Bilimbi and Averrhoa Carambola)

Nutritional composition, total phenolic content, total flavonoid, antioxidant capacity, and antioxidant vitamins of bilimbi (Averrhoa bilimbi) and carambola (Averrhoa carambola) were determined and compared in this study. Bilimbi was found to contain higher moisture, ash, carbohydrate, protein, fat, and dietary fiber compared to carambola. Total phenolic content was higher in carambola although bilimbi yielded more total flavonoid. Vitamins A, C, and E contents of bilimbi were also higher than carambola. Antioxidant and scavenging activity as determined by β-carotene bleaching assay and DPPH radical scavenging assay of carambola were significantly (p < 0.05) higher than bilimbi. These results suggested that carambola was a potent natural antioxidant food and that contribution of phenolic compounds to its antioxidant capacity was greater than that of antioxidant vitamins.     

Effects of Nanoparticles on Film Properties of Waterborne Acrylic Emulsions

Waterborne acrylic emulsion was obtained by using methyl methacrylate, ethyl and butyl acrylate monomers. Emulsions containing nanoparticles were prepared by blending the stable dispersions containing SiO₂ or MMT nanoparticles. The films were prepared from emulsions and coating tests were applied. The physical properties of prepared emulsions are better than the commercial emulsions. The addition of the nanoparticles especially SiO₂ have positive effect on the resistance to environmental conditions of emulsions. Waterborne acrylic emulsions containing nanoparticles prepared in this study can be used in the manufacturing of the semi-lustrous emulsion type nano paint with low cost, high performance and environmentally friendly.     

Size optimization of a PV/wind hybrid energy conversion system with battery storage using response surface methodology

This paper aims to show the use of the response surface methodology (RSM) in size optimization of an autonomous PV/wind integrated hybrid energy system with battery storage. RSM is a collection of statistical and mathematical methods which relies on optimization of response surface with design parameters. In this study, the response surface, output performance measure, is the hybrid system cost, and the design parameters are the PV size, wind turbine rotor swept area and the battery capacity. The case study is realized in ARENA 10.0, a commercial simulation software, for satisfaction of electricity consumption of the global system for mobile communications (GSM) base station at Izmir Institute of Technology Campus Area, Urla, Turkey. As a result, the optimum PV area, wind turbine rotor swept area, and battery capacity are obtained to be 3.95 m², 29.4 m², 31.92 kWh, respectively. These results led to $37,033.9 hybrid energy system cost, including auxiliary energy cost. The optimum result obtained by RSM is confirmed using loss of load probability (LLP) and autonomy analysis.     

In vitro cytotoxicity of monticellite based bioactive ceramic powder synthesized from boron derivative waste

The cytotoxicity of monticellite based bioactive ceramic powder, which was synthesized from boron derivative waste has been determined by in vitro assays of MTT, NRU, and JC-1 staining. The toxicity of powder on different mammalian cell lines (3T3-L1, HUVEC, CRL-2120) was evaluated at the concentrations of 10, 100, 200, 400 and 800?µg/mL to justify its potential for biomedical applications. The obtained results showed that monticellite based bioactive ceramic powder possesses not only bioactive feature but also biocompatible characteristic at the concentration range of 10–200?µg/mL. Hence, monticellite based bioactive ceramics have high potential as a bone graft substitute for bone void filling and coating applications.     

Fuzzy Gain Scheduled Continuous Stirred Tank Reactor with Particle Swarm Optimization based PID control Minimizing Integral Square Error

In this paper, a new control scheme, the gain scheduled Particle Swarm Optimization (PSO) based PID, is proposed for a continuous stirred tank reactor (CSTR). CSTR is a highly nonlinear process that exhibits stability in certain regions and instability in some regions. Generally, PID controllers are used in these processes. Tuning of the PID controller is required to guarantee the best performance of the CSTR. The proposed scheme implements the characteristics of the PSO's global optimization to tune the PID's control parameters: k_p, k_i, k_d, to obtain the best control effect by minimizing Integral Square Error online. The PID controller parameters tuned for each region using PSO are gain scheduled using fuzzy control. Fuzzy gain-scheduling is a special form of fuzzy control that uses linguistic rules and fuzzy reasoning to determine the controller parameter transition policy for the dynamic plant subject to large changes in its operating state. Simulation results show the feasibility of using the proposed controller for the control of the dynamic nonlinear CSTR.     

Effects of ageing on the biomechanical properties of rat articular cartilage

Previous studies have demonstrated that male Sprague Dawley (SD) rats experience age-related bone loss with the same characteristics as that in ageing men. As articular cartilage, like bone, is a critical component of the health and function of the musculoskeletal system, the authors hypothesized that articular cartilage in the untreated male SD rats could be a suitable model for studying the age-related deterioration of articular cartilage in men. To test this hypothesis, male SD rats were killed at between 6 and 27 months. The right femur of each rat was removed. The effects of ageing on the structural integrity of the distal femoral articular cartilage were studied by biomechanical testing with a creep indentation apparatus. The aggregate modulus, Poisson's ratio, permeability, thickness, and percentage recovery of articular cartilage were determined using finite element/non-linear optimization modelling. No significant differences were observed in these biomechanical properties of the distal femoral articular cartilage as a function of age. Therefore, untreated male SD rats appear to be unsuitable for studying the age-related changes of articular cartilage as they occur in men. However, and more intriguingly, it is also possible that ageing does not affect the biomechanical properties of articular cartilage in the absence of cartilage pathology.     

Sustainable Microwave Assisted Synthesis and Anti-proliferative Response of Starch-Based CNT-IO and CNT-ZO Nanocomposites: A Comparative Study

Journal of Inorganic and Organometallic Polymers and Materials - Starch based carbon nanotubes-iron oxide (CNT-IO) and carbon nanotubes-zirconium oxide (CNT-ZO) nanocomposites (NCs) were fabricated...