Green Extraction of Phenolic Compounds from Blueberry (Vaccinium corymbosum L.) By-Products Using Natural Deep Eutectic Solvents for Cosmetic Applications †

What if the blueberry leftovers from your juice could become the next anti-aging skincare ingredient? Scientists have found a green way to unlock their hidden power.

Every year, tons of blueberry pomace—the leftover skins, seeds, and pulp from juice making—go to waste. But this by-product is a treasure trove of bioactive compounds, just waiting to be tapped. In a new study, researchers used five different betaine-based natural deep eutectic solvents (NaDES) to extract these compounds, each paired with a different hydrogen-bond donor like citric acid, lactic acid, or glycerol. The goal? To find a greener, more sustainable alternative to traditional solvents like water and ethanol.

The team analyzed the extracts using advanced liquid chromatography and mass spectrometry, profiling anthocyanins and other phenolics. They also tested antioxidant power with DPPH and ABTS assays. Among the NaDES, the betaine-citric acid mix stood out, showing high phenolic recovery and strong radical scavenging activity. But they didn't stop there—they also tested its ability to inhibit elastase and tyrosinase, enzymes linked to skin aging, and then incorporated it into an anti-aging cosmetic formulation.

The result? A safe, ready-to-use cosmetic ingredient that skips the need for solvent removal. This isn't just about skincare—it's a step toward a circular economy, where waste becomes value. Blueberry pomace, once discarded, could now be the secret to youthful skin and a healthier planet.

Key Points

• Betaine-citric acid NaDES showed best phenolic recovery.
• Extracts inhibited elastase and tyrosinase, anti-aging enzymes.
• NaDES enable solvent-free cosmetic ingredients from waste.