Immobilization of mutated xylanase from Neocallimastix patriciarum in E. coli and application for kraft pulp biobleaching

As an important enzyme, xylanase is widely used in the food, pulp, and textile industry. Different applications of xylanase warrant specific conditions including temperature and pH. This study aimed to carry out sodium alginate beads as carrier to immobilize previous reported mutated xylanase from Neocallimastix patriciarum which expressed in E. coli, the activity of immobilization of mutated xylanase was elevated about 4% at pH 6 and 13% at 62 °C. Moreover, the immobilized mutated xylanase retained a greater proportion of its activity than the wide type in thermostability. These properties suggested that the immobilization of mutated xylanase has potential to apply in biobleaching industry.

Entropy generation of MHD flow of sodium alginate (C6H9NAO7) fluid in thermal engineering

In this paper, impacts of magnetic field and porosity on the entropy generation of sodium-alginate (C6H9NaO7) fluid are studied. C6H9NaO7 is taken over a moving and heated vertical wall. Heat transfer is due to free convection. Initially, the problem is formulated in the form of PDEs along with physical conditions and then written in non-dimensional form. Problem is solved via Laplace transform and expression in analytical form is established for temperature and velocity field. The related relations for entropy generation and Bejan number and entropy generation are also examined. Nusselt number and Skin-friction are calculated and plotted in graphs. For numerical computations, a finite difference scheme is used using MATLAB software. The results in tables and graphs are discussed for embedded parameters. It is found that the magnetic field and porosity have strong influence on velocity, entropy generation and Bejan number. For greater Hartman number, entropy generation magnitude is greater compared to the Bejan number, conversely, this variation in Bejan number is more efficient. The porosity effect showed that if the medium is more porous, the entropy generation can decreases 50% when porosity increase from Ka = 1 to Ka = 2, however the Bejan number increases.

Whole Wheat Crackers Fortified with Mixed Shrimp Oil and Tea Seed Oil Microcapsules Prepared from Mung Bean Protein Isolate and Sodium Alginate

Shrimp oil (SO) rich in n-3 fatty acids and astaxanthin, mixed with antioxidant-rich tea seed oil (TSO), was microencapsulated using mung bean protein isolate and sodium alginate and fortified into whole wheat crackers. SO and TSO mixed in equal proportions were emulsified in a solution containing mung bean protein isolate (MBPI) and sodium alginate (SA) at varied ratios. The emulsions were spray-dried to entrap SO-TSO in MBPI-SA microcapsules. MBPI-SA microcapsules loaded with SO-TSO showed low to moderately high encapsulation efficiencies (EE) of 32.26–72.09% and had a fair flowability index. Two selected microcapsules with high EE possessed the particle sizes of 1.592 and 1.796 µm with moderate PDI of 0.372 and 0.403, respectively. Zeta potential values were −54.81 mV and −53.41 mV. Scanning electron microscopic (SEM) images indicated that microcapsules were spherical in shape with some shrinkage on the surface and aggregation took place to some extent. Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC) analyses of samples empirically validated the presence of SO-TSO in the microcapsules. Encapsulated SO-TSO showed superior oxidative stability and retention of polyunsaturated fatty acids (PUFAs) to unencapsulated counterparts during storage of 6 weeks. When SO-TSO microcapsules were fortified in whole wheat crackers at varying levels (0–10%), the crackers showed sensorial acceptability with no perceivable fishy odor. Thus, microencapsulation of SO-TSO using MBPI-SA as wall materials could be used as an alternative carrier system, in which microcapsules loaded with PUFAs could be fortified in a wide range of foods.

Enhancing the Optical Properties of Chitosan, Carboxymethyl Cellulose, Sodium Alginate Modified with Nano Metal Oxide and Graphene Oxide

The solution casting method was utilized to synthesize nanocomposite films of chitosan (Cs)/CuO, Cs/graphene oxide (GO), carboxymethyl cellulose (CMC)/TiO2, CMC/GO, sodium alginate (Na Alg)/TiO2, and Na-Alg/GO owing to their various applications. The influence of CuO, TiO2 and GO concentration on the optical properties of Cs, CMC and Na-Alg films was studied by UV-Vis Spectroscopy. The absorbance of Cs, CMC and Na-Alg increased with increasing the filler content, thus reflecting the dependence of Cs, CMC, and Na-Alg properties on the nanofiller content, and confirming the interactions between individual polymers and CuO, TiO2 and GO nanoparticles. The obtained absorbance values were then used to calculate the absorption coefficient and, hence, the optical band gap values. The characteristic absorption bands of CuO and TiO2 underwent a redshift by increasing the filler content. The results showed that the optical band gap of Cs, CMC, and Na-Alg decreased with filler content, and they possessed 1, 2 and 2 band gaps respectively. The obtained results recommended that Cs, CMC, and Na-Alg nanocomposites can be used in optoelectronic devices.