Alpha-Substituted Derivatives of Cinnamaldehyde as Tyrosinase Inhibitors: Inhibitory Mechanism and Molecular Analysis

Abstract

Alpha-substituted derivatives of cinnamaldehyde (alpha-bromocinnamaldehyde, alpha-chlorocinnamaldehyde, and alpha-methylcinnamaldehyde) were used as inhibitors on mushroom tyrosinase. The result showed that three compounds can reduce both monophenolase and diphenolase activity on tyrosinase, and the inhibition was reversible. The IC 50 values of alpha-bromocinnamaldehyde, alpha-chlorocinnamaldehyde, and alpha-methylcinnamaldehyde were 0.075, 0.140, and 0.440 mM on monophenolase and 0.049, 0.110, and 0.450 mM on diphenolase, respectively. The inhibition types and constants on diphenolase for these inhibitors were further studied. The molecular inhibition mechanisms of tyrosinase by the derivatives were investigated by UV-scanning study, fluorescence quenching, and molecular docking. These assays demonstrated that the derivatives could decrease the formation of o-quinones, and all derivatives were static quenchers of mushroom tyrosinase. Docking results implied that they could not form metal interactions with the copper ions of the enzyme, whereas they could interact with the amino acid residues of active site center. This research on alpha-substituted derivatives of cinnamaldehyde as tyrosinase inhibitors would lead to advances in the field of antityrosinase.

A Novel Inhibitor Against Mushroom Tyrosinase with a Double Action Mode and Its Application in Controlling the Browning of Potato

“…3b (curve II). Similar results were obtained in the investigation of mushroom tyrosinase inhibition by other inhibitors, such as p-methoxybenzaldehyde thiosemicarbazone (MBT) and some alpha-substituted derivatives of cinnamaldehyde (Chen et al 2012;Cui et al 2015). The increase in lag time indicates an inhibition of monophenolase activity, which subsequently led to a reduction in total tyrosinase activity (Anish and Adinpunya 2014).…”

Inhibition of glycosidase by ursolic acid: in vitro, in vivo and in silico study

“…The quenching rate constant value ( k q ) of ursolic acid binding to α‐amylase and α‐glucosidase was 2.3 × 10 10 (mol L −1 ) −1 S −1 and 1.46 × 10 11 (mol L −1 ) −1 S −1 , respectively. It was concluded from the experiments that the ursolic acid binding to glycosidase was a static process by forming a complex because their quenching constant was greater than the maximum collision constant [2.0 × 10 10 (mol L −1 ) −1 S −1 ] …”

Cinnamaldehyde loaded chitosan/tripolyphosphate nanoassemblies: Fabrication, characterization, and in vitro evaluation of antioxidant activity

“…Nowadays, the use of natural bioactive ingredients from plants in the food and/or the pharmaceutical industries is attracting particular attention due to their health benefits and in line with the consumer safety concerns regarding the use of synthetic ones (Assadpour & Jafari, ). Cinnamaldehyde (CIN), 3‐phenyl‐2‐propenal found in the essential oil of cinnamon ( Cinnamomum zeylanicum L.) (60–75% of the total oil) has been reported to exhibit diverse biological functions including antimicrobial, antioxidant, anti‐biofilm, anti‐hyperglycemic, antitumor, and anticancer activity (Cui et al, ). Due to their strong antimicrobial/antioxidant efficacy, this compound is widely used as a food flavoring agent and food additive/preservative (Doost, Dewettinck, Devlieghere, & Van der Meeren, ).…”