Integrated Evaluation of NADES for Green Extraction of Bioactive Compounds from Strawberries: A Study on Anthocyanin, Antioxidant Activity, Chemometric FTIR Profiling

What if the key to unlocking nature's antioxidant treasure chest lies not in harsh chemicals, but in a simple mixture of natural compounds? A new study reveals that certain eco-friendly solvents can outperform traditional ethanol in extracting health-promoting compounds from strawberries.

Strawberries are more than just a sweet treat—they're packed with anthocyanins and phenolics, natural compounds with potent antioxidant powers. But extracting these treasures efficiently and sustainably has been a challenge. Enter Natural Deep Eutectic Solvents (NADES), a new class of green solvents made from cheap, biodegradable ingredients like choline chloride and organic acids.

In this study, researchers compared five NADES formulations against ethanol for extracting bioactive compounds from strawberries. They measured total anthocyanins, total phenolics, and antioxidant activity via the DPPH assay, while also using FTIR spectroscopy and Principal Component Analysis (PCA) to profile the extracts chemically.

The standout performer was NADES E (choline chloride:lactic acid), which delivered the highest yields: 125.57 mg/100g anthocyanins, 11,032 mg GAE/g phenolics, and 89.15% antioxidant activity. Interestingly, NADES A (choline chloride:citric acid) produced similar yields but showed the strongest FTIR signals for phenolic groups (-OH, C=O, C=C), hinting at a different selectivity.

PCA clearly separated NADES A, C, and E from ethanol, proving that these green solvents offer superior compound selectivity and profile retention. This integrated approach—combining quantitative and qualitative analysis—underscores the importance of evaluating both efficiency and selectivity when designing sustainable extraction methods.

Key Points

• NADES E outperformed ethanol in extracting anthocyanins and phenolics from strawberries.
• NADES A showed strongest FTIR signals for phenolic groups, indicating different selectivity.
• PCA separated NADES A, C, E from ethanol, proving superior compound selectivity.