Zein/Cress seed gum nanoparticle-stabilized artemisia annua essential oil pickering emulsion: A new encapsulation system

• Zein and cress seed gum (CG) could form nanoparticles as Pickering emulsifiers. • Zein-to-CG ratio of 2:1 nanoparticles demonstrated favorable colloidal stability. • ZCGP S 2:1 showed the smallest average particle size. • Pickering emulsion loaded with 4 % Artemisia annua essential oil (A. annua EO) exhibited high encapsulation efficiency. • Pickering emulsion loaded with A. annua EO indicated significant antioxidant and antibacterial ability. Pickering emulsions offer a promising surfactant-free strategy for the sustained delivery and encapsulation of essential oils (EO). In this study, biodegradable nanoparticles composed of zein and cress seed gum (ZCGPs) were developed to stabilize an Artemisia annua EO Pickering emulsion. Among the formulations, ZCGPs with a 2:1 zein-to-CG ratio exhibited optimal characteristics, including a particle size of 176.4 nm and a zeta potential of –37.1 mV, indicating good colloidal stability. The contact angle of ZCGPs2:1 was measured at 77.16°, reflecting a well-balanced amphiphilic nature suitable for effective emulsion stabilization. Pickering emulsions incorporating 2 %, 4 %, and 6 % (v/v) EO were prepared, with 4 % formulation showing the optimum properties with an average droplet size of 4.44 μm, a PDI of 0.42, and a zeta potential of –48.6 mV. This emulsion also achieved high encapsulation efficiency (85.52 %), strong antioxidant activity (38.43 %), and demonstrated uniform droplet morphology. Antimicrobial assessments revealed increased inhibition zones with higher EO content, with Staphylococcus aureus being more sensitive than Pseudomonas aeruginosa . These findings highlight the potential of ZCGPs-stabilized Pickering emulsions for encapsulating bioactive compounds and their promising application in active packaging systems.