In order to reveal the active components of whitening, anti-diabetes, anti-gout, and anti-dementia in PCR, the key enzyme inhibitors of these pharmacological activities are screened, such as the anti-diabetes α-GLU inhibitor (α-GLUI), the anti-gout XOD inhibitor (XODI), the whitening TYR inhibitor (TYRI), and the ACHE inhibitor (ACHEI). Here, TYR is linked to diabetes mellitus.