Coacervate Microcapsules of Citrus aurantifolia Essential Oil (LOs): Optimization and Their Antibacterial Activity Study

Abstract Optimization of microcapsule shell to preserve Citrus aurantifolia lime oil (LOs), employing a coacervation method, and their inhibition against bacteria was conducted. Pre‐optimization of the microcapsule properties was evaluated from three types of shell combination; alginate/gelatin (A/G), gum arabic/gelatin (GA/G), and gum arabic/chitosan (GA/C). The best pairs were further improved for their ratios ranged from 1 : 3, 1 : 3.25, 1 : 3.5, 1 : 3.75, and 1 : 4. The performance of microcapsules was evaluated based on yield, oil content, encapsulation efficiency, particle size and distribution, morphology, and release kinetic. Additionally, antibacterial activity was subsequently performed using the Kirby Bauer method. The result showed that the LOs were effectively coated by alginate/gelatin (1 : 3.75) with yield, encapsulation efficiency (EE), and oil content (OC) of 48±1 %, 90±10 %, and 58±7 %, respectively. The spherical microcapsules were homogenously well distributed with an average particle size of 1.802±0.082 μm. Avrami's kinetic model revealed a first‐order kinetic mechanism of LOs release ( k =1.1 ×10 −4 s −1 ). The LOs microcapsules exhibited the highest antibacterial activity against Staphylococcus epidermidis , followed by Klebsiella pneumonia, and Staphylococcus aureus . Thereby, the LOs microcapsules were potentially applied in the field of health, food, and textile as an antibacterial agent.