Enhanced extraction of phenolic compounds from mango by-products using deep eutectic solvents

Deep eutectic solvents (DESs) potential for the extraction of polyphenolic compounds (PC) from mango by-products (peel and seed) was evaluated. Ultrasound (US) and agitation were applied to evaluate the effects of solvent and extraction methodology. The extracts were characterized with antioxidant capacity and HPLC-DAD profile. A theoretical study was performed using density functional theory and the QTAIM approach. β-alanine and choline chloride based DESs were effective to extract PC from peel and seed. Some DES increased PC extraction up to three times for peel (23.05 ± 1.22 mg/g DW) and up to five time for seeds (60.01 ± 1.40 mg/g DW). The PC profile varied with the solvent (DES vs EtOH/MeOH), procedure (US vs agitation) and material (peel or seed). Mangiferin extraction from peels was significantly increased with β-alanine based DES (676.08 ± 20.34 μg/gDW). The strength of H-bonds had a determining effect on the viscosity of DESs. The solute-solvent solvation energy was suitable to estimate the strength of H-bond interactions between DES and target compounds. This study demonstrates the remarkable capacity of DESs to extract PC from mango by-products and provides insights into the factors controlling extraction properties.

This work was supported by the grant PID2019-107980RB-I00 funded by MCIN/AEI/10.13039/501100011033. The authors are grateful to the graduate Lucía Gimenez for her technical support. Dr. Ojeda thanks the Carolina Foundation and the Ministry of Education of Argentina for the grant received. Dr. Sgroppo thanks the Argentinean Agency for the Scientific and Technological Promotion (ANPCyT) PICT 2019/3395 and SGCYT UNNE (PI 18F020).

Peer reviewed