Mass spectrometry is the best and dominant technique for the analytical investigation of molecules and complex mixtures in modern life sciences and bio-analytical approaches. Especially, the high-resolution mass spectrometry (HRMS) that is important in determining the elemental composition of a molecule and in gaining partial structural insights using mass spectral fragmentations. Furthermore, mass spectral library searches to achieve the structure elucidation. And through the data processing and statistical analysis can understand the drug metabolic pathway.
Tyrosinase (EC 1.14.18.1), a copper-containing oxidoreductase, also commonly called polyphenol oxidase, has two catalytic activities: o-hydroxylation of monophenols and aerobic oxidation of o-diphenols. It is mainly involved in the formation of pigments such as melanins. The activity of mushroom tyrosinase can be measured by monitoring the conversion of phenolic compounds into quinine derivatives using the spectrophotometer. But this method cannot directly distinguish a single active compound.
In this aim, we used the inhibitor kojic acid treatment with tyrosinase. The reactant via ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS) to analysis, software processed and statistical analysis. We found some ions in chromatography were from kojic acid treated with tyrosinase. Next step, we will use HRMS to elucidate the structure and clear the metabolic pathway in compound between tyrosinase.
This method is potential in finding the tyrosinase inhibitory activities compounds in complex natural product extract and accelerate the activities compounds finding in natural material research.
Keyword: tyrosinase, HRMS, UPLC-MS