Inhibitory activity and mechanism of trilobatin on tyrosinase: kinetics, interaction mechanism and molecular docking

Abstract

Tyrosinase is the rate-limiting enzyme controlling the production of melanin, and tyrosinase inhibitors can regulate the overproduction of melanin by inhibiting tyrosinase activity, which is an effective method to treat...

Inhibition characteristics and mechanism of tyrosinase using five citrus flavonoids: A spectroscopic and molecular dynamics simulation study

“…Thus, both substrate and inhibitor could attach to the enzyme simultaneously in two different sites dependently, and the degree of inhibition affected by the change in the substrate concentration is dependent on the interaction between the two sites of substrate and inhibitor (Saboury, 2009). This same inhibition type has also been found in previous studies, in which epigallocatechin‐3‐gallate, gallocatechin gallate, homoisoflavonoids and trilobatin inhibited the diphenolase activity of tyrosinase (Song et al, 2021; Wang et al, 2021; Yu et al, 2021). These results suggest that the monophenolase and diphenolase activities of tyrosinase respond to one active site only during the three different stages of oxidation (Sánchez‐Ferrer et al, 1995).…”

“…Previous studies have similarly reported that hesperidin inhibited tyrosinase activity by only approximately 5% when L‐dopa was used as the substrate (Zhang et al, 2007). In addition, more recent reports found that hesperetin, naringenin, neohesperidin and naringin exhibited no distinct inhibition of the diphenolase activity of tyrosinase, resulting in the catalyzation of L‐dopa to Dopa quinone (Yu et al, 2021). Thus, hesperetin, naringenin, neohesperidin and naringin mainly inhibit the monophenolase activity of tyrosinase.…”

“…The tyrosinase activity was assessed by the visible‐light absorbance method in vitro according to the report of Yu et al (2021) with some correction. First, 50 μl of tyrosinase (0.2 mg/ml) was mixed in phosphate buffered saline (PBS) with 50 μl of kojic acid or citrus flavonoids at different concentrations, ranging from 0 μmol/mL to 2 μmol/ml.…”

“…However, as a synthesized medicine kojic acid is unstable and its long term use is thought to cause cancer (Saeedi et al, 2019). Therefore, the development of natural products that can effectively inhibit tyrosinase with minor side effects is essential as a successful alternative to synthetic drugs (Yu et al, 2021).…”

“…

Tyrosinase catalyzes the production of melanin via a two-step process: first, the hydroxylation of L-tyrosine to L-dopa (monophenolase activity), followed by its further oxidation to dopaquinone (diphenolase activity) (Figure 1a, Yu et al, 2021). Although melanin contributes to protecting the skin from ultraviolet radiation, the overproduction of melanin is also an important pathogenic factor in the development

…”