Preparation and characterization of edible carboxymethyl cellulose films containing natural antibacterial agents: Lysozyme.

Carboxymethyl cellulose (CMC) films containing lysozyme (Lys) were prepared in this study and changes in properties of the films were investigated. Enhancement in mechanical properties was observed with increased Lys, maximum (0.05 g/100 mL) reached to 39.07 MPa (TS) and 25.04 % (EAB). Meanwhile, water resistance ability improved, the minimum (0.05 g/100 mL) reached to 0.42 g·mm·(m2·h·KPa)-1, 84.62 % of pure CMC film. Thermogravimetric test showed better thermal stability of films. Scanning electron microscope illustrated that few cracks on surface of films. Fourier Transform infrared spectroscopy supported that more intermolecular hydrogen between Lys and CMC was formed with increased Lys, yet keeping increasing formed less intermolecular hydrogen. X-ray Diffraction observed the aggregated Lys by crystal structure. Antibacterial test showed an inhibitory effect on two common food-borne pathogens. Weight loss experiment indicated that films reduced the dry consumption of meat. Overall, the modification of CMC film by adding Lys was effective.

Preparation and characterization of iron-copper binary oxide and its effective removal of antimony(III) from aqueous solution.

An Fe-Cu binary oxide was fabricated through a simple co-precipitation process, and was used to remove Sb(III) from aqueous solution. X-ray diffraction, scanning electron microscopy, energy dispersive X-ray and N2 adsorption-desorption measurements demonstrated that the Fe-Cu binary oxide consisted of poorly ordered ferrihydrite and CuO, and its specific surface area was higher than both iron oxide and copper oxide. A comparative test indicated that Fe/Cu molar ratio of prepared binary oxide greatly influenced Sb(III) removal and the optimum Fe/Cu molar ratio was about 3/1. Moreover, a maximum adsorption capacity of 209.23 mg Sb(III)/g Fe-Cu binary oxide at pH 5.0 was obtained. The removal of Sb(III) by Fe-Cu binary oxide followed the Freundlich adsorption isotherm and the pseudo-second-order kinetics in the batch study. The removal of Sb(III) was not sensitive to solution pH. In addition, the release of Fe and Cu ions to water was very low when the pH was greater than 6.0. X-ray photoelectron spectroscopy analysis confirmed that the Sb(III) adsorbed on the surface was not oxidized to Sb(V).