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

Abstract Phenolic compounds from elderberry ( Sambucus nigra L.) were extracted using a green, water-based method assisted by β-cyclodextrin (β-CD). Central composite design was applied to evaluate the effects of three key parameters: β-CD concentration (1–3% w/v), liquid-to-solid (L/S) ratio (10–30% w/v), and extraction time (30–90 min). Multiple responses were modeled, including total phenolic content (TPC), flavonoids (TFC), total monomeric anthocyanin and total proanthocyanin contents (TMAC, TPAC), and antioxidant activity (DPPH, FRAP, CUPRAC). TPC followed a quadratic trend, while TFC peaked around 2% β-CD. TMAC and TPAC increased linearly across the tested ranges. Among antioxidant assays, DPPH showed the highest sensitivity to process conditions, whereas FRAP and CUPRAC were less affected. Time had a relatively minor influence within the tested interval. Optimal extraction was achieved at moderate L/S ratios and ~ 2% β-CD, balancing efficiency while minimizing dilution and mass transfer limitations. Overall, β-CD-assisted extraction is an effective, low-solvent approach for recovering elderberry phenolics. These findings support future studies on inclusion mechanisms, stability, and scale-up through techno-economic and life-cycle assessments.