Optimizing prodigiosin nanoencapsulation in different wall materials by freeze drying: Characterization and release kinetics

Abstract

Prodigiosin, a microbial pigment, was produced using Serratia marcescens and encapsulated with β-cyclodextrin (BCD), maltodextrin (MD), gum Arabic (GA), and soy protein isolate (SPI) to enhance stability and bioavailability. Emulsions were prepared by dissolving wall materials (5 % w/v) in water, mixing with prodigiosin in ethanol (1:1), and adding Tween 80 as an emulsifier. The mixture was ultrasonicated, homogenized, and freeze-dried to form nanoparticles. Encapsulation efficiencies were 81.15 % (PBCDN), 76.93 % (PMDN), 89.15 % (PGAN), and 85.22 % (PSPIN). Particle size ranged from 115.63 to 181.42 nm, with PGAN having the largest size. FTIR confirmed successful encapsulation, while DSC indicated enhanced thermal stability, particularly in GA-based nanoparticles. In vitro release studies showed controlled release, with PGAN exhibiting the slowest release in gastric conditions. These results suggest GA is the most effective wall material for improving prodigiosin stability and controlled release for food, pharmaceutical, and cosmetic applications.

Keywords: Encapsulation; Release kinetics; Ultrasonication; Wall material.