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The growing global awareness for environmental protection has inspired the exploration on producing active packaging films from bio-based materials. In present work, three types of active agents were studied by incorporating thymol(T), kesum(K), and curry(C) (10% wt.) into polylactic acid (PLA) to produce PLA-10T, PLA-10K, and PLA10-C packaging films via solvent casting method. The morphology, functional chemistry, thermal stability, permeability, and antimicrobial properties were evaluated for PLA films. Functional chemical analysis confirmed the presence of interfacial bonding between aromatic groups of active agents and PLA carbonyl group. PLA-10K exhibited the highest thermal resistance comparing to PLA-10T and PLA-10C while water vapor barrier was enhanced after incorporation of active agents. Qualitative observation had indicated that chicken meat could be preserved in the active films until 15 days, while odourless and firm texture properties retained in food sample. For disc diffusion assay (in vitro), it showed positive results against Gram-positive bacteria (Staphylococcus aureus) whereas with negative results against Gram-negative bacteria (Escherichia coli) and Aspergillus Brasiliensis due to embedded active agents within PLA matrix. We concluded that produced active agents filled PLA films potential to use in food packaging application to enhance the shelf life of meats, fruits and vegetables product. Unlabelled Image • Fabrication of polylactic acid (PLA) film with active agent for food preservation. • Incorporation of thymol, kesum, and curry oils into PLA matrix via solvent casting. • Smooth cross-section feature showcased by thymol and kesum integrated PLA film. • Stable thermo-molecular changing behavior between kesum and PLA. • Long-lasting time for chicken meat preservation in active agents filled PLA films. [ABSTRACT FROM AUTHOR]

Olive fiber is a renewable natural fiber which has potential as an alternative biomass for extraction of microcrystalline cellulose (MCC). MCC has been widely applied in various industries owing to its small dimensional size for ease of reactive fabrication process. At present study, a serial treatments of bleaching, alkaline and acid hydrolysis was employed to extract OL-BLF, OL-PUF, and OL-MCC respectively from olive stem fiber. In morphology examination, a feature of short micro-crystallite particles was obtained for OL-MCC. The particle size was found gradually reducing from OL-PUF (305.31 μm) to OL-MCC (156.06 μm) due to the disintegration of cellulose fibrils. From physicochemical analysis, most lignin and hemicellulose components had been removed from OL-BLF to form OL-PUF with individually fibril structure. The elemental analysis revealed that highly pure cellulose component was obtained for OL-MCC. Also, the rigidity had been improved from OL-BLF to OL-PUF, while with the highest for OL-MCC with 74.2% crystallinity, endowing it as a reliable load-bearing agent. As for thermal analysis, OL-MCC had the most stable heat resistance in among the chemically-treated fibers. Therefore, olive MCC could act as a promising reinforcing agent to withstand harsh conditions for variety fields of composite applications. [ABSTRACT FROM AUTHOR]