Encapsulation and characterization of garcinia atroviridis rinds water extracts loaded nanoparticles

Abstract

Garcinia atroviridis fruit has been shown to express anti-obesity activity as a result of its bioactive compound, hydroxycitric acid (HCA). HCA is effective in decreasing appetite, inhibiting fat synthesis, and reducing body weight. However, HCA is very unstable towards certain conditions thus limiting its bioavailability. To overcome the issue of HCA instability, HCA was encapsulated in chitosan (CS) nanoparticles in this study. CS nanoparticles were prepared based on ionic gelation using sodium tripolyphosphate (TPP) as a cross-linking agent. The concentration of chitosan and TPP: chitosan volume ratios were varied and the resulting nanoparticles were characterized based on zeta potential, particle size, encapsulation efficiency (EE%), and kinetics release. The most optimum nanoparticle was obtained with a combination of 1.5 mg/mL chitosan with a CS: TPP volume ratio of 4: 1. Zeta potential was measured by approximately 49 mV. The size of the particle at optimum condition was found to be 140 nm and the nanoparticle had high encapsulation efficiency (87.55±5.35%). G. atroviridis extract release from CS nanoparticles followed either Higuchi or Korsmeyer Peppas kinetic model. FT-IR studies indicated that G. atroviridis was encapsulated in CS nanoparticles. The present study revealed that concentration of chitosan, and CS: TPP volume ratio can significantly change the physical characteristics of the nanoparticles and this provides an avenue for formulators to engineer CS nanoparticles according to needs.