Preparation, Characterization, and Controlled Release of Fenugreek Seed Extract-Loaded Nanoliposomes with Chitosan Surface Decoration

In the present study, the fenugreek seed extract was loaded into chitosan-coated nanoliposomes (FCNL) to enhance the stability and preserve the bioactivity of extracted flavonoids. To accomplish this, the preparation and optimization results showed that 500-W ultrasonic power, 1.5% extract loading, and 0.5% chitosan coating produced stable FCNL with an average particle size of 178.7 nm, PDI (0.20), and zeta potential of + 15.9 mV with the highest encapsulation efficiency of 86.18%. The structural and thermal characterization by FTIR, XRD, and TGA suggested strong electrostatic interaction and enhanced thermal stability of FCNL as compared to FWNL. The morphological study indicated spherical nanoparticles with smooth surfaces. The results of storage stability revealed that the prepared nanoparticles were sensitive to light and could be effectively stored at low temperatures (4 °C) in dark conditions for a longer period of time with maximum flavonoid retention of 96.27%. The prepared FCNL showed significant antibacterial and free radical (DPPH and ABTS) scavenging activities. The results of the in vitro release profile revealed that the FCNL was stable during gastric digestion with only an 11.31% release rate which enhanced to a highest of 79.67% in simulated intestinal fluid (SIF) after 6 h of digestion. Subsequently, the FCNL presented notable inhibition activities against α-amylase (76.89 ± 2.07%), α-glucosidase (89.35 ± 1.87%), and pancreatic lipase (74.22 ± 2.05%). Hence, the bioactivity, stability, and release profile of fenugreek flavonoids can be effectively preserved using nanoliposomes as carrier agents. Conclusively, the prepared nanoparticles can be used in food and pharmaceutical industries as natural antidiabetic and hypolipidemic agents.