Polysaccharide-Based Multilayer Nano-Emulsions Loaded with Oregano Oil: Production, Characterization, and In Vitro Digestion Assessment

Area of Science:

• Food Science and Technology
• Materials Science
• Biotechnology

Background:

• Growing demand for natural, consumer-friendly ingredients in the food industry.
• Need for effective delivery systems to protect bioactive compounds in food products.
• Potential of biopolymers as natural emulsifiers and protective agents.

Purpose of the Study:

• To develop and characterize multilayer nano-emulsion systems for encapsulating oregano essential oil.
• To optimize the nano-emulsion formulation using natural polysaccharides.
• To evaluate the stability and bioavailability of encapsulated oregano essential oil.

Main Methods:

• Production of multilayer nano-emulsions using high-energy methods.
• Incorporation of octenyl succinic anhydride modified starch, chitosan, and carboxymethylcellulose.
• Characterization of particle size, polydispersity index, zeta potential, and encapsulation efficiency.
• Stability assessment at different temperatures (4 °C and 20 °C) over 21 days.
• In vitro evaluation of oregano essential oil release under simulated digestive conditions.

Main Results:

• Optimal conditions yielded nano-emulsions with specific particle sizes and zeta potentials for one, two, and three layers.
• High encapsulation efficiency of 97.1% for oregano essential oil was achieved.
• The three-layer nano-emulsion system significantly enhanced oregano essential oil bioavailability (40% available) compared to free oil (13%) after simulated digestion.

Conclusions:

• Multilayer nano-emulsions formulated with modified starch, chitosan, and carboxymethylcellulose are efficient carriers for oregano essential oil.
• These systems offer enhanced protection and improved bioavailability of bioactive compounds.
• The developed nano-emulsions represent a promising natural delivery system for the food industry.