Preliminary screening of 44 plant extracts for anti-tyrosinase and antioxidant activities

In order to find new tyrosinase inhibitors and antioxidant materials, we investigated 44 plants, which were evaluated for the anti-tyrosinase and antioxidant activities. The mushroom tyrosinase inhibition assay and 2, 2-Diphenyl-1- picrylhydrazyl [DPPH] radical scavenging assay were conducted to evaluate these activities. Among all tested plant extracts, Morus alba L. [positive control], Rhodiola crenulata [Hook. f. et Thorns.] H. Ohba, Momordica charantia L., Cuminum cyminum L. et al exhibit higher tyrosinase inhibition. Rhodiola crenulata [Hook. f. et Thorns.] H. Ohba, Rosa rugosa Thunb. and Eugenia caryophyllata Thunb. perform the highest antioxidant activity, similar to vitamin C [the positive control]. A low positive correlation is found in the DPPH radical scavenging and tyrosinase inhibition assay. Considering these factors, the extracts of Rhodiola crenulata [Hook. f. et Thorns.] H. Ohba, Alpinia officinarum Hance and Zanthoxylum bungeanum Maxim, exhibit high anti-tyrosinase and antioxidant activities and could be used in the cosmetic industry. Further studies are warranted to characterize the compounds responsible for the anti-tyrosinase and antioxidant properties of these plant extracts