Sustainable barley starchs-based bioplastics functionalized with Ocimum tenuiflorum extract

The increasing environmental concerns associated with petroleum-based plastics have accelerated the development of sustainable, biodegradable packaging materials derived from biodegradable and renewable packaging materials with improved functional properties. The study aimed to develop a biodegradable barley starch-based plastic with antimicrobial properties for packaging applications. The novelty lies in using barley as a matrix for making bioplastic functionalized with Ocimum tenuiflorum (holy basil) was developed as an environmentally friendly active packaging material. The bioplastics were prepared using the solution-casting method, with water, glycerin, and vinegar as plasticizers. The effects of adding basil extract on the structural, mechanical, thermal, moisture-management, antibacterial, and biodegradation properties of the bioplastics were systematically studied. Scanning electron microscopy (SEM) showed that the bioplastic had a dense and homogenous morphology without significant pores or defects. Fourier-transform infrared (FTIR) spectroscopy confirmed the incorporation of basil-derived functional groups into the starch matrix. Thermal analysis showed improved thermal stability with increasing basil extract content. The glass transition temperature (Tg) increased from 65.4°C to 80.2°C, while the total mass loss decreased from 90.86% to 84.94%. The basil-enriched bioplastics also showed a higher residual mass (5.92–6.20%) than the control sample (2.41%), indicating improved thermal resistance. The developed bioplastics showed a bursting strength ranging from 3.5 to 5.14 kg/cm² and controlled moisture absorption. Soil burial testing showed 42% biodegradation after 12 weeks. In addition, the films demonstrated antibacterial activity against Staphylococcus aureus. These findings highlight the potential of barley starch-based bioplastics enriched with holy basil as environmentally friendly materials for active and sustainable packaging applications.