Combined supercritical CO₂ extraction and liposomal encapsulation of bioactive compounds from vranac grape skins for topical applications

Abstract

The wine industry produces significant amounts of waste, particularly grape pomace, which consists of skins, seeds, and stems. While this byproduct poses environmental challenges, it is also a rich source of bioactive compounds, such as polyphenols, including quercetin and resveratrol. This study investigates the potential of Vranac grape skins, known for their high polyphenol content, as a source of bioactive components for cosmetic applications, with a specific focus on the effect of liposomal encapsulation on their antioxidant activity. Bioactive compounds were extracted from grape skins using supercritical CO₂ extraction and encapsulated into DPPC liposomes, suitable for topical applications. Chemical analysis of the extract, performed using Orbitrap mass spectrometry, confirmed a high resveratrol content. Antioxidant activity, measured by EPR spectroscopy, showed moderate activity against DPPH radicals and strong activity toward hydroxyl and superoxide radicals. Liposomes were characterized using Dynamic Light Scattering (DLS) and zeta potential measurements, while EPR analysis indicated moderate liposomal membrane fluidity. The results demonstrated that the encapsulated extract retained its antioxidant properties, making it a stable and effective agent for topical use. This approach not only addresses waste management challenges but also provides a sustainable foundation for developing high-value cosmetic products.

Acknowledgment: The financial support for this project was provided by the Science Fund of the Republic of Serbia, project Waste2Protect Bees No. 5455; Ministry of Science, Technological Development and Innovation of the Republic of Serbia, contract numbers: 451-03-65/2024 03/200146 and 451-03-66/2024-03/200146.