Applications of choline amino acid ionic liquid in extraction and separation of flavonoids and pectin from ponkan peels

ABSTRACT

Choline leucine ionic liquid solution was chosen to simultaneously extract flavonoids and pectin from ponkan peels, which were subsequently isolated by the corresponding K₃PO₄-based aqueous biphasic systems (ABS). Under optimized conditions of 54% solution for 100 min extraction at liquid–solid ratio 17, the predicted yields of flavonoids and pectin achieved 1.33% and 13.42%, respectively, the flavonoids determined directly after extraction and the pectin after ABS purification, with the two corresponding measured yields of 1.26% ± 0.04% and 12.85% ± 0.51%. Under optimal extraction, crude flavonoids contained maximal total flavonoid content of about 20% ± 1% after purification of the ABS involving 25% K₃PO₄ and dilution precipitation. What was directly isolated from K₃PO₄-rich phase was presumed to be a modified pectin.

KEYWORDS:

• Aqueous biphasic systems
• choline amino acid ionic liquids flavonoids
• pectin

Acknowledgements

Runping Wang and Yuena Chang contributed equally to this work.

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China (project no. 21406262) and the Hunan Province Education Foundation (project no. 2012594).