Researchers at IMDEA Materials Institute and the Institute of Polymer Science and Technology (ICTP-CSIC) have developed an innovative biodegradable multilayer film capable of protecting and controlling the release of anthocyanins inside the body.

Published in the International Journal of Biological Macromolecules, this breakthrough opens the door to more effective functional foods and supplements for intestinal health.

Anthocyanins are natural pigments found in fruits such as blueberries and grapes, known for their powerful antioxidant and anti-inflammatory properties. However, their application in food and therapeutic products is limited because they are extremely fragile.

They degrade rapidly in the gastrointestinal tract, reducing their bioavailability to less than 1%. To overcome this challenge, the team behind the recent publication created a “dual stabilisation” platform.

First, they encapsulated the anthocyanins in zein nanoparticles (a corn protein). They then integrated these nanoparticles into a multilayer film made from pectin and chitosan, two natural biopolymers.

The resulting system proved to be the most effective, achieving an encapsulation efficiency of 77% and superior mechanical resistance compared to other formulations.

“The main advantage of this biomaterial is its controlled and pH-sensitive release capability,” explained the lead author of the publication, Dr. Sabina Lachowicz Wiśniewska, a Marie Skłodowska-Curie Actions postdoctoral researcher at IMDEA Materials.

“The film protects the anthocyanins in the acidic environment of the stomach, releasing less than 30% of the compound, and then releases them gradually under intestinal conditions, reaching nearly 80% release after 12 hours.”

“This selective behaviour is crucial to ensure that the bioactive compounds reach the area of maximum absorption intact,” she added.

This development has significant potential for the nutraceutical and functional food industries. It could be used to create next-generation oral supplements for the prevention of diseases such as inflammatory bowel disease (IBD), or to enrich foods that preserve the bioactivity of their healthy components until consumption.

The research team behind the study includes Dr Sabina Lachowicz Wiśniewska, Dr Maciej Haranczyk, and Dr Juan Pedro Fernández Blázquez from IMDEA Materials, as well as Dr Miryam Criado-González and Dr Rebeca Hernández from ICTP-CSIC.

The “Enhancing Bioavailability of Beneficial Polyphenolic Compounds in Food via Advanced Materials Engineering” (BIOCOMAT) project will run from 2024-2026 and is funded by the MSCA Postdoctoral Fellowships 2023 Programme (HORIZON-MSCA-2023) through the European Union under Grant Agreement 101151044. Views and opinions expressed are, however, those of the author(s) only and do not necessarily reflect those of the European Union. Neither the European Union nor the granting authority can be held responsible for them.