Development and characterization of sodium alginate and β-cyclodextrin nanoemulsions encapsulating betel leaf (Piper betle L.) extract for enhanced antimicrobial efficacy against foodborne pathogen

Abstract

This study aims to investigate the physical stability, droplet size, zeta potential, and antimicrobial properties of nanoemulsions formulated with betel leaf extract using β-cyclodextrin (CD) and sodium alginate (SA) biopolymers. Nanoemulsions with β-cyclodextrin exhibit superior stability at lower temperatures, with limited droplet size, and strong electrostatic repulsion. Morphological images demonstrate the successful encapsulation of betel leaf extract within both biopolymers, highlighting their potential for antimicrobial applications. Both CD and SA nanoemulsions display inhibitory effects on bacterial strains (E. coli, P. aeruginosa, L. monocytogenes, S. aureus, and B. cereus) and fungal growth (A. brasiliensis, R. stolonifer, F. oxysporum, and C. albicans). SA nanoemulsions show higher antimicrobial activity due to H⁺ ion release, particularly against A. brasiliensis and C. albicans. These findings underscore the potential of betel leaf extract nanoemulsions, especially those with SA, for various antimicrobial applications for sustainable food packaging, highlighting their significance in addressing microbial challenges.

Keywords: Antimicrobial property; Betel leaf extract; Nanoemulsion; Sodium alginate; β-Cyclodextrin.