Muhammad Usman

The goal of synthesizing more environmentally friendly high-water-absorbing gels (HWAGs) is to reduce the consumption of petroleum resources. We also aimed to make rational use of plant straw. Reed straw (RS) was modified using strong irradiation. Acrylamide (AM) and acrylic acid (AA) were grafted onto the cellulose for graft copolymerization reactions. The cellulose and gels were analyzed using infrared spectroscopy (IR), scanning electron microscopy (SEM), and thermogravimetric (TG) analysis. To reduce the crystallinity of the RS, the optimal irradiation dosage is 96 kGy. Single-factor and orthogonal experiments were conducted to determine the optimal reaction conditions for IRSC-HWAG: the monomer ratio m(AA):m(AM) was 1.5; The material ratio of (m_(AA+Am):m_(IRSC)) was 9:1; The neutralization degree of AA was approximately 90%; The irradiation dose was 5 kGy, with a dose rate of 2.0 kGy/h; the crosslinking agent dosage was 1.2%. The absorption rate of deionized water (Q_d) by the gels was approximately 1160 g/g; the absorption rate of salt water (Q_s) by the gels was approximately 99 g/g. A water-retention experiment demonstrated the IRSC-HWAG’s superior water-retention properties. These properties were compared with those of resins synthesized using pure chemical reagents. This experiment provides valuable reference data for the further development of plant-based water-retention agents.

Carboxymethyl chitosan (CMCS) is ideal for active packaging due to its non-toxicity and degradability, but its poor film-forming performance (strong hydrophilicity, weak mechanical properties, and low antibacterial activity) limits practical use. This study prepared a new edible antibacterial presFervation film (SDEWL-CMCS) by adding salted duck egg white lysozyme (SDEWL) to CMCS (as the film-forming substrate). It investigated how SDEWL concentration affects the composite film’s properties (thickness, water solubility, moisture/oil resistance, mechanical properties, and antibacterial activity) and tested the film’s preservation effect on small nectarines. The results showed the composite film had significantly improved packaging and antibacterial properties: compared to pure CMCS film, it had higher tensile strength, lower water solubility, better oil resistance and water vapor barrier performance, and stronger antibacterial activity against Escherichia coli and Staphylococcus aureus (larger inhibition zone diameters). The SDEWL-CMCS film effectively preserved small nectarines by inhibiting surface bacteria, regulating the preservation environment, and delaying fungal decay. This study confirms the film’s potential as a sustainable fruit packaging alternative, providing a theoretical basis for developing new fruit/vegetable preservation packaging and reducing the food industry’s reliance on non-degradable petroleum-based packaging.