Fabrication of Citrus bergamia essential oil-loaded sodium caseinate/peach gum nanocomplexes: Physicochemical, spectral, and structural characterization

Abstract

`The objective of current research was to encapsulate citrus bergamia essential oil (CBEO) in nanocomplexes composed of sodium caseinate (SC) and peach gum polysaccharide (PG) in various ratios (SC/PG-1:0, 0:1, 1:1, 1:3, and 3:1). The nanocomplexes formed by the combination of SC and PG in a ratio of 1:3 exhibited a zeta potential of -21.36 mV and a PDI of 0.25. The CBEO-loaded SC/PG (1:3) nanocomplexes revealed the maximum encapsulation efficiency (82.47 %) and loading capacity (1.85 %). FTIR also confirmed the secondary structure variations in response to different ratios of CBEO-loaded SC/PG nanocomplexes. In addition, the XRD and fluorescence spectroscopy analysis also revealed structural changes among CBEO nanocomplexes. The thermal capability of CBEO-loaded SC/PG (1:3) nanocomplexes via TGA showed the minimum weight loss among other complexes. SEM and CLSM analysis demonstrated the uniform distribution and spherical morphology of CBEO-loaded SC/PG (1:3) nanocomplexes. The antioxidant activity of free CBEO was significantly improved in CBEO-loaded nanocomplexes. Likewise, the inhibitory activity of CBEO-loaded nanocomplexes exhibited significantly higher antibacterial action against S. aureus and E. coli. The aforementioned perspective suggests that SC/PG nanocomplexes have potent potential to serve as highly effective nanocarriers with a broad spectrum of uses in the pharmaceutical and food sectors.

Keywords: Antimicrobials; Citrus bergamia essential oil; Sodium caseinate/peach gum.