With the increasing demand of natural whitening and antioxidant ingredient, preliminary screening of hot water extracts from sixty Chinese herbal medicines with tyrosinase inhibitory activity and antioxidant properties was conducted in this study. The results showed that 14 out of 60 Chinese herbal medicines, including Rhus chinensis, Paeonia suffruticosa, Ginkgo biloba, Ligustium Wallichii, Polygala tenuifolia , Cinnamomum cassia , Acanthopanax gracilistylus , Nelumbo nucifera, Baphicacanthes cusia, Carthamus tinctorius, Rheum tanguticum , Rose taiwanensis , Scutellaria baicalensis and Pueraria Pseuo-hirsut , exhibited more than 70% of tyrosinase inhibitory activity. On the other hand, no inhibitory tyrosinase activity was found in Eriobotrya japonica.
Among fourteen Chinese herbal medicines with higher inhibition activity of tyrosinase, R. chinensis, R. laevigata, R. tanguticum, N. nucifera, B. cusia and A. gracilistylus showed higher DPPH radical scavenging activity.The IC50 of DPPH radical scavenging activity ranged from 0.15 to 0.66 mg/ml. The higher antioxidant activity determined by conjugated diene method was shown by R. chinensis, followed by A.gracilistylus, R. laevigata, R. tanguticum, B. cusia and N. nucifera was meanwhile,the strongest reducing power was also shown by R. chinensis, followed by R. laevigata, R. tanguticum, N.nucifera, A. gracilistylus and B.cusia. The reducing power of R. chinensis, was 1.6 times that of BHA and 2.3 times that of Vitamin C. Reducing power increased with increasing concentration of hot water extract of R. laevigata, R. tanguticum, A.gracilistylus and B. cusia. The higher amounts of total phenolics were noted in R. chinensis, R. laevigata, R. tanguticum, N. nucifera, A. gracilistylus and B. cusia. Among fourteen tested Chinese herbal medicines, 846,586,375,220,124 and 102 mg of gallic acid equivalent per gm dry weight of hot water extract were obtained in R. chinensis, R. laevigata, R. tanguticum, N. nucifera, A. gracilistylus and B. cusia, respectively, In conclusion, six Chinese herbal medicines with higher tyrosinase inhibitory activity and antioxidant properties including R. chinensis, R.laevigata, R. tanguticum, N.nucifera, A. gracilistylus and B. cusia, was obtained.