Carboxymethyl cellulose (CMC) bioplastic shows great promise for sustainable food packaging. This study synthesized zinc oxide nanoparticles (ZnO NPs) from pineapple waste via green synthesis and incorporated them into CMC to develop enhanced nanocomposite films. Key steps included preparing ZnONP powder and formulating ZnONP-CMC (ZCMC) (1.0% w/v) solutions for film fabrication. The nanocomposites were characterized using FTIR, XRD, SEM-EDX, TGA, and DSC to assess structural integrity and thermal stability. Physical properties showed enhancement, including a thickness of 0.17.05 mm, opacity of 17%, moisture content of 52.38%, and water solubility of 64.52%. The mechanical properties also improved significantly, with a tensile strength of 26.30 MPa and elongation at a break of similar to 50%. FTIR and XRD confirmed the successful incorporation of ZnO NPs, which improved the crystallinity and structural integrity of the CMC matrix. Notably, the ZCMC nanocomposite exhibited rapid biodegradation within 9 days under soil conditions, highlighting its potential for reducing environmental impact. In conclusion, adding ZnO NPs to CMC films notably improves their physical, mechanical, and thermal characteristics, rendering them ideal for food packaging. While the mechanical and biodegradation properties are promising for food packaging applications, future research should focus on evaluating the antimicrobial properties and practical applications of the ZCMC films in food preservation.

Zinc oxide nanoparticles (ZnO NPs) are inorganic compounds listed as generally recognized as safe (GRAS) materials and have been used in plant production as well as for plant disease control. This study investigated the antibacterial efficacy of ZnO NPs with various surface areas against Xanthomonas campestris pv. campestris, assessed the effectiveness of ZnO NPs in controlling black rot disease in Chinese kale, and examined the influence of ZnO NPs application on soil bacterial communities. The results showed that ZnO NPs with high surface area effectively inhibited X. campestris pv. campestris by restraining growth and causing cell damage. Seed treatment and foliar spray application of high surface area ZnO NPs at 250 mu g/mL significantly reduced the disease severity of black rot. Furthermore, in the greenhouse experiment, the soil bacterial communities in the treatment of plants applied with ZnO NPs did not differ from those in soil of nontreated plants. Therefore, ZnO NPs have the potential to serve as an alternative substance for plant disease management.