Acylating blueberry anthocyanins with fatty acids: Improvement of their lipid solubility and antioxidant activities

Aimed at exploring the impact of fatty acid side chains on the anthocyanins, n-valeric acid, n-decanoic acid and myristic acid were used to grafting onto the blueberry anthocyanins, and the acylating degree value of the of n-valeric acid acylated anthocyanins (Va-An), n-decanoic acid acylated anthocyanins (De-An) and myristic acid acylated anthocyanins (My-An) reached 6.43 %, 7.56% and 8.38 %, respectively. After acylation modification, the octanol–water partition coefficient of the anthocyanins increased from −0.20 (native anthocyanins, Na-An) to 0.65 (Va-An), 0.66 (De-An) and 0.72 (My-An), respectively, indicating the increasement of the lipid solubility. Besides, although the DPPH clearance of acylated anthocyanins was lower than that of native anthocyanins, the inhibition ratio of β-carotene bleaching and malonaldehyde reduction effect of the acylated blueberry anthocyanins in Caenorhabditis elegans were both stronger than that of native anthocyanins, which might be caused by the improvement of lipid solubility of the anthocyanins.