Green extraction of mulberry anthocyanin with improved stability using β-cyclodextrin.

BACKGROUND

Mulberry anthocyanins is reported to possess various biological activities and it is unstable during the extraction or food production. The use of organic solvents for extraction of mulberry anthocyanins may cause environmental pollution and safety concerns. Therefore, the aim of this study was to investigate the effect of green extraction solvent (cyclodextrin) on recovery of anthocyanin from mulberry fruits, as well as the thermal stability of anthocyanin.

RESULTS

β-cyclodextrin (β-CD) or hydroxypropyl-β-cyclodextrin (Hβ-CD) showed better anthocyanin extraction efficiency than that of water and ethanol aqueous solution in all tested mulberry cultivars. Molecular docking study indicated that anthocyanin (cyanidin-3-O-glucoside) was encapsulated in the cavity of β-cyclodextrin, thus enhanced the solubility of anthocyanin. The extraction process was subsequently optimized using a Box Behnken design. The optimal extraction conditions for anthocyanin and antioxidant activity were found at extraction temperature of 20°C, extraction time of 44.95 min, and β-CD concentration of 45 g/L. Furthermore, the degradation kinetic study demonstrated that addition of β-CD could significantly improve the thermal stability of anthocyanin during extraction, with the activation energy (Ea ) of anthocyanin degradation increased from 63.06 KJmol-1 to 76.77 KJmol-1 .

CONCLUSIONS

Overall, our study suggests that β-CD is an alternative green extraction solvent for recovery of anthocyanins and addition of β-CD may potentially increase the thermal stability of anthocyanin during the extraction, which may give a guidance for functional beverage production. This article is protected by copyright. All rights reserved.