Tyrosinase inhibitory mechanism and anti-browning properties of novel kojic acid derivatives bearing aromatic aldehyde moiety

• Published in: Current research in food science Vol. 6; p. 100421
• Main Authors: Peng, Zhiyun, Wang, Guangcheng, He, Yan, Wang, Jing Jing, Zhao, Yong
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.01.2023; Elsevier
• Subjects: Anti-browning; Anti-tyrosinase; Aromatic aldehydes; Anti-browning; Aromatic aldehydes; Anti-tyrosinase
• ISSN: 2665-9271; 2665-9271
• DOI: 10.1016/j.crfs.2022.100421

Kojic acid-aromatic aldehydes 6a-6m were synthesized and screened for their anti-tyrosinase activities. These compounds showed potently anti-tyrosinase activity with IC50 values in the range of 5.32 ± 0.23 to 77.89 ± 3.36 μM compared with kojic acid (IC50 = 48.05 ± 3.28 μM). Thereinto, compound 6j with 3-fluorine and 4-aldehyde substitutions showed the most potent anti-tyrosinase activity (IC50 = 5.32 ± 0.23 μM). Enzyme kinetic study revealed that 6j is a noncompetitive tyrosinase inhibitor (Ki = 2.73 μM). The action mechanism of 6j was evaluated by fluorescence spectrum quenching, molecular docking, 1H NMR titration, etc. The anti-browning assay showed that 6j could delay the enzymatic browning of fresh-cut apples. Besides, the cell viability assay proved that 6j had a good safety profile as an anti-browning agent. Hence, these results identify a new class of anti-tyrosinase and anti-browning agents for further investigation in the food industry. [Display omitted] •Designed and synthesis of kojic acid-aromatic aldehydes (6a-6m).•Compound 6j exhibited more potent inhibitory activity than kojic acid.•Compound 6j effectively reduced the enzymatic browning of fresh-cut apples.•Compound 6j exhibited low cytotoxic activity in a human normal cell line.