Tyrosinase Inhibitory Activity of Extracts from Prunus persica

The demand for skin-whitening agents is high across the world, including Asian countries. An extensive screening using a tyrosinase inhibition assay was performed in order to discover novel plant materials. In our research program investigating a safe and effective agent, 50% ethanolic extracts prepared from discarded parts of Prunus persica were screened for in vitro tyrosinase inhibitory activity. Among the extracts tested, twig extract showed the most potent inhibitory activity: 38% inhibition at 500 mu g/mL. The investigation of active compounds in twig extract found four flavanones that acted as moderate inhibitors, including (-)-prunin, persiconin, (+)-dihydrokaempferol, and (-)-naringenin. These compounds were only observed in the twig extract following preliminary quantification by HPLC, with the following concentrations: (-)-prunin, 1.8 mg/g sample; persiconin, 0.8 mg/g sample; (+)-dihydrokaempferol, 0.8 mg/g sample; (-)-naringenin, 1.7 mg/g sample. These results suggest that twig extracts can be more useful for skin-whitening compared with other parts of the plant. In addition, a new constituent of twig extract was identified, namely isoquercitrin, which suggests that twig extract can be a potent source of flavones and flavanones. Further studies on the identification of novel compounds from twig extract are now underway in our laboratory.

Automated summary

The study found that twig extracts from Prunus persica contain four flavanones that act as moderate inhibitors of tyrosinase, as well as a new constituent called isoquercitrin. These results suggest that twig extracts may be more beneficial for skin-whitening compared to other parts of the plant.