Green Extraction and Optimization of Bioactive Compounds from Elderberry (Sambucus nigra L.) by β-cyclodextrin-Assisted Extraction

What if the secret to unlocking elderberry's powerful antioxidants lies in a sugar molecule that acts like a molecular cage? New research shows that a simple, water-based extraction using β-cyclodextrin can efficiently capture these valuable compounds, without harsh solvents.

Elderberries are packed with phenolic compounds—nature's tiny defenders with potent antioxidant power. But traditional extraction methods often rely on organic solvents that are neither eco-friendly nor efficient. Now, scientists have turned to a green alternative: water, boosted by β-cyclodextrin (β-CD), a cyclic sugar that can encapsulate and stabilize these delicate molecules.

Using a central composite design, the team systematically varied three key parameters: β-CD concentration (1–3% w/v), liquid-to-solid ratio (10–30% w/v), and extraction time (30–90 min). They measured multiple responses, including total phenolic content (TPC), flavonoids, anthocyanins, proanthocyanins, and antioxidant activity via DPPH, FRAP, and CUPRAC assays.

The results revealed intriguing patterns: TPC followed a quadratic trend, while flavonoid content peaked at around 2% β-CD. Anthocyanins and proanthocyanins increased linearly across the tested ranges. Among the antioxidant assays, DPPH was the most sensitive to process conditions, while FRAP and CUPRAC remained relatively stable. Time had only a minor effect.

The optimal extraction occurred at moderate liquid-to-solid ratios and approximately 2% β-CD, striking a balance between efficiency and minimizing dilution and mass transfer limitations. This β-CD-assisted approach offers a low-solvent, effective method for recovering elderberry phenolics, with promising implications for future studies on inclusion mechanisms, stability, and scale-up.

Key Points

• Green water-based extraction with β-cyclodextrin.
• Optimal at ~2% β-CD and moderate liquid-to-solid ratio.
• DPPH most sensitive to process conditions.