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Among the main biodegradable food packaging materials, poly-lactic acid (PLA) is a commercially successful polymer used notably in the food packaging industry. In this study, active PLA films containing different percentage of anise essential oil (AE) (0, 0.5, 1 and 1.5% v/v) were developed, and characterized by physical, mechanical and antibacterial analysis. Based on physical examinations, thermal stability of PLA/AE films was greater than the neat PLA film, and the minimum water vapor permeability (WVP) was recorded for PLA/0.5AE film (1.29 × 10 11 g/m s), while maximum WVP was observed for PLA/1.5AE (2.09 × 1011 g/m s). Moreover, the lightness and yellowness of the composites were decreased by the addition of AE. For the PLA composites with 1.5% AE, the tensile strength decreased by 35% and the elongation break increased by 28.09%, comparing to the pure PLA. According to the antibacterial analysis, the minimum inhibitory concentrations of PLA/AE film were 5 to 100 mg/mL and the active composite could create visible inhibition zones of 14.2 to 19.2 mm. Furthermore, the films containing AE inhibited L. monocytogenes and V. parahaemolyticus in a concentration-dependent manner. The confirmation of the success of the incorporation of EOs into the PLA films was further evaluated using principal component analysis, where positive results were obtained. In this context, our findings suggest the significant potency of AE to be used as an antibacterial agent in active food packaging.

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The physical, mechanical, and biological behaviour of copper containing glass polyalkenotare cements were investigated, where copper (Cu2+) was incorporated into a SiO2-ZnO-CaO-SrO-P2O5 based glass system. Three GPCs were formulated for this study, a Control and two Cu-GPCs with 6 (Cu-1) and 12 (Cu-2) Mol.% of CuO substituted for the SiO2 in the glass. Rheological evaluation of GPCs determined that the addition of the Cu decreases the working and setting times in the cements. The mechanical properties of the cements were evaluated after 1 - 21 days incubation in DI water. The compressive strength of the cements were found to range between 21-36 MPa, with Cu-1 having the highest compressive strength. Biaxial flexural strength and Shear Bond Strength of the GPCs were found to increase with respect to time and were higher for the Cu-GPCs at 14 MPa and 2.1 MPa respectively. Bioactivity testing was conducted using Simulated Body Fluid (SBF) which revealed CaP precipitants on each of the GPCs surfaces. The effect o f Cu addition to the GPCs greatly enhanced the antibacterial inhibition zone (IZ) when tested in E.coli (3mm), S.aureus (24mm) and S.epidermidis (22mm). Cytocompatibility testing revealed more favorable MC3T3 osteoblast cell viability when compared to the Control GPC.