Functionalities and antioxidant properties of protein hydrolysates from the muscle of ornate threadfin bream treated with pepsin from skipjack tuna

Functional properties and antioxidant activities of protein hydrolysates prepared from ornate threadfin bream (Nemipterus hexodon) muscle, using skipjack tuna pepsin, with different degrees of hydrolysis (DH: 10%, 20% and 30%), were evaluated. Emulsifying and foaming properties of hydrolysates were governed by their DH and concentrations used. Hydrolysates with 20% DH had the highest scavenging activities for ABTS and DPPH radicals. However, chelating activity of hydrolysates for ferrous ion increased as DH increased. Size exclusion chromatography of the hydrolysate with 20% DH using Sephadex G-25 revealed that antioxidative peptides with molecular weight of approximately 1.3 kDa exhibited the highest ABTS radical-scavenging activity. In vitro simulated gastrointestinal digestion indicated that ABTS radical-scavenging activity of the antioxidative peptides was not affected by pepsin hydrolysis, whilst further digestion by pancreatin enhanced the activity. Therefore, protein hydrolysate from the muscle of ornate threadfin bream produced by skipjack tuna pepsin can be used as a promising source of functional peptides with antioxidant properties.     

Chromatographic separation of glucopyranosyl sinapate from canola meal

The compound 1-O-β-D glucopyranosyl sinapate (GPS), a phenolic glycoside, was separated from ethanolic extracts of defatted canola meal by a two-step chromatographic method. The first step involved Sephadex LH-20 chromatography with methanol as the eluting solvent. The solvent from the fraction containing GPS was evaporated, and glucopyranosyl sinapate was subsequently separated by a semi-preparative high-performance liquid chromatography method with an RP-18 column and a mobile phase consisting of water/acetonitrile/acetic acid (88∶10∶2, vol/vol/vol).     

Genetic Algorithm�CArtificial Neural Network Modeling of Moisture and Oil Content of Pretreated Fried Mushroom

In this research, the effect of different pretreatments (osmotic dehydration and gum coating) on moisture and oil content of fried mushroom was investigated, and artificial neural network and genetic algorithm were applied for modeling of these parameters during frying. Osmotic dehydration was performed in solution of NaCl with concentrations of 5% and 10%, and methyl cellulose was used for gum coating. Either pretreated or control samples were fried at 150, 170, and 190 °C for 0.5, 1, 2, 3, and 4 min. The results showed that osmotic dehydration and gum coating significantly decreased (0–84%, depending upon the processing conditions) oil content of fried mushrooms. However, moisture content of fried samples diminished as result of osmotic pretreatment and increased by gum coating. An artificial neural network was developed to estimate moisture and oil content of fried mushroom, and genetic algorithm was used to optimize network configuration and learning parameters. The developed genetic algorithm–artificial neural network (GA–ANN) which included 17 hidden neurons could predict moisture and oil content with correlation coefficient of 0.93 and 96%, respectively. These results indicating that GA–ANN model provide an accurate prediction method for moisture and oil content of fried mushroom.     

Investigation on dye ability and antibacterial activity of nanolayer platinum coated polyester fabric using DC magnetron sputtering

In this research work, one side of polyester fabrics was coated by platinum using DC magnetron sputtering. The dye ability of coated and uncoated samples to different natural and synthetic dyes was evaluated. The antibacterial counting test was used for determination of antibacterial efficiency of both treated and untreated samples. The results show that, the existence of platinum nanolayer on the surface of PET fabrics causes improve the dyeability of fabrics. The improvement for natural dyes is more significant than for synthetic dye. According to antibacterial activity tests, platinum itself has no antibacterial effect against Staphylococcus aureus. However, the natural dyed Pt-coated samples show moderate antibacterial effect.     

Flame Retardant Properties of Plasma Pretreated/Metallic Salt Loaded Cotton Fabric Before and After Direct Dyeing

In this research work, cotton fabrics were pretreated with low temperature plasma (LTP) and then inoculated in various metallic salts and flame retardancy of cotton fabric was investigated. More polar functional groups were present on the substrate surface after LTP pretreatment. Titanium dioxide (TiO₂), zinc sulfate (ZnSO₄), lead (II) acetate [Pb(C₂H₃O₂)₂], aluminium sulfate [Al₂(SO₄)₃] and silver nitrate (AgNo₃) were used as metallic salts. The flame retardancy of the samples was characterized by limiting oxygen index (LOI) and char yield. Good flame retardant activity for Al₂(SO₄)₃ and AgNo₃ treated fabrics were achieved, however, the effect of TiO₂ and ZnSO₄ on flame retardany of cotton fabrics was moderate. It was concluded that, nitrogen plasma pretreatment, improve the flame retardant properties of cotton samples. The plasma treated and Aluminium sulfate loaded cotton fabric sample has a LOI value of 23.3. It shows that, nitrogen plasma pretreatment has synergistic effect on metallic salts for improving the flame retardant properties of cotton samples. In this research work, the dyeability of samples after loading with metallic salts was investigated. Also effect of dyeing on flame retardant properties was studied. The cotton fabrics treated with metallic salts demonstrate an excellent dyeability property. Color intensities of the dyed fabrics were measured by using a UV VIS–NIR Reflective Spectrophotometer, over the range of 200–800 nm. The results showed that, by using silver nitrate as mordant before dying, the relative color strength (K/S values) of the dyed fabrics has been increased. Water drop test and wash fastness determination (ISO 105-C01) were conducted. Also Electronic Crock meter/Rubbing Fastness Tester AATCC 8 was used to determine the color fastness of textiles. We also concluded that dyeing the plasma treated and inoculated cotton fabrics do not have any negative effect on flame retardancy of cotton fabric.     

Endogenous antioxidants and stability of sesame oil as affected by processing and storage

The effect of processing of coated and dehulled sesame seeds on the content of endogenous antioxidants, namely sesamin, sesamolin, and γ-tocopherol in hexane-extracted oils, was studied over 35 d of storage under Schaal oven test conditions at 65°C. Seeds examined were Egyptian coated (EC) and dehulled (ED) and Sudanese coated (SC) varieties. Processing conditions of raw (RW) seeds included roasting at 200°C for 20 min (R), steaming at 100°C for 20 min (S), roasting at 200°C for 15 min plus steaming for 7 min (RS) and microwaving at 2450 MHz for 15 min (M). The sesamin content in fresh oils from EC, ED, and SC raw seeds was 649, 610, and 580 mg/100 g oil, respectively. Corresponding values for the content of sesamolin in oils tested were 183, 168 and 349 mg/100 g oil, respectively. Meanwhile, the content of γ-tocopherol, the only tocopherol present in the oils, ranged from 330 to 387 mg/kg sample. The effect of processing on changes in the sesamin content in oils from coated seeds was low and generally did not exceed 20% of the original values. On the other hand, oils from dehulled seeds underwent a more pronounced decrease in their sesamin content than the oil from coated seeds after 35 d of storage at 65°C. The corresponding changes in sesamolin and γ-tocopherol contents were more drastic. The RS treatment, which would be the optimal to prepare sesame oil with better quality, was found to retain 86, 80 and 60% of the sesamin, sesamolin and γ-tocopherol, respectively, originally present in the seeds after the storage period. The loss in the content of endogenous antioxidants present in the oils paralleled an increase in their hexanal content.     

Acetate and phosphate anion adsorption linear sweep voltammograms simulated using density functional theory

Specific adsorption of anions to electrode surfaces may alter the rates of electrocatalytic reactions. Density functional theory (DFT) methods are used to predict the adsorption free energy of acetate and phosphate anions as a function of Pt(1 1 1) electrode potential. Four models of the electrode potential are used including a simple vacuum slab model, an applied electric field model with and without the inclusion of a solvating water bi-layer, and the double reference model. The linear sweep voltammogram (LSV) due to anion adsorption is simulated using the DFT results. The inclusion of solvation at the electrochemical interface is necessary for accurately predicting the adsorption peak position. The Langmuir model is sufficient for predicting the adsorption peak shape, indicating coverage effects are minor in altering the LSV for acetate and phosphate adsorption. Anion adsorption peak positions are determined for solution phase anion concentrations present in microbial fuel cells and microbial electrolysis cells and discussion is provided as to the impact of anion adsorption on oxygen reduction and hydrogen evolution reaction rates in these devices.