This study was conducted to investigate the antioxidative activity and tyrosinase inhibitory activity of 50%ethanol extract and its fractions from the branch of Rhododendron schlippenbachii. In DPPH radical scavenging ability,butanol and ethyl acetate fractions showed 59.98% and 55.17% of relative activity compared with positive control (ascorbicacid), but the 50% ethanol extract showed relatively low activity. In nitric oxide (NO) scavenging ability, the ethyl acetateand butanol fractions showed 141.80% and 131.55% relative activity compared with ascorbic acid as used for posi-tive control. On the other hand, tyrosinase inhibitory activity of the ethyl acetate and butanol fractions showed about twicehigher activity than positive control (arbutin). It means that the ethyl acetate and butanol fractions from the extract of R.schlippenbachii branch has ability for used as effective radical scavenger and tyrosinase inhibitor.

The investigation was made about distribution and ecological characteristics of Rhododendron mucronulatum var. mucronulatum, R. dauricum and R. schlippenbachii on Mt. Changbai in China. The Ericaceae plants are known to be highly ornamental and easy to cultivate. The results of investigations are like followings. The plant species diversity was the highest in habitats of R. mucronulatum var. mucronulatum, followed by those of R. schlippenbachii and R. dauricum. R. mucronulatum var. mucronulatum community was found in the northwest exposure areas of 300m in altitude. Corylus heterophylla, Carex humilis var. nana, Atractylodes japonica species also grew in the R. mucronulatum var. mucronulatum community. R. dauricum communities were widely distributed in the west exposure areas of 1226-1860m above sea level. R. schlippenbachii populations were found in areas of under 300m above sea level, which has dry soil. But humidity of air was relatively high in the place. Artemisia japonica, Lespedeza bicolor and Dactylis glomerata were found around the habitats of R. schlippenbachii. Phalanx type of plants were dominant near the habitats of Ericaceae plants as 61%. Further, there appeared higher plant life totalling to 72 taxa comprising 54 species, 16 varieties and 2 forma with 31 families and 59 genuses at the whole survey area. Among these, Compositae plants excellent in resistance to environment was surveyed the most, accounting for 30.0%.