Natural deep eutectic solvents as a biocompatible tool for the extraction of blueberry anthocyanins

The extraction of blueberry anthocyanins with natural deep eutectic solvents (NADES) based on choline chloride:glycerol:citric acid was optimized by simplex centroid design to find the best molar ratio for the solvent. Choline chloride:glycerol:citric acid at the molar ratio of 0.5:2:0.5 (NADES 6) was the optimal NADES for extraction. NADES 6 was as efficient as the conventional organic solvent (methanol:water:formic acid) when compared at the same sample:solvent ratio and yielded about 76 % of blueberry anthocyanins compared to an exhaustive extraction with the organic solvent. NADES 6 yielded higher proportion of arabinoside anthocyanins and lower proportion of galactoside anthocyanins than the organic solvent. Thus, NADES can be assumed as a cheaper substitute for organic solvents, yielding biocompatible extracts of blueberry that are selectively enriched in arabinoside anthocyanins.