• Korean Journal of Pharmacognosy
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• v.33 no.4 s.131
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• pp.399-403
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• 2002

Three melanogenesis inhibitors were isolated from the roots and rhizomes of Veratrum nigrum L. and were identified as (3S,20S,25S)-22,26-iminocholesta-5,22(N)-dien-3-ol (verazine), (3S,2OR,25S)-22,26-iminocholesta-5,22(N)-dien-3-ol (epi-verazine) and (3R,23R)-14,15,16,17- tetradehydroveratraman-3,23-diol (veratramine) on the basis of their spectroscopic data. It was turned out that these compounds did not directly inhibit tyrosinase activity, the key enzyme responsible for the formation of melanin pigment while these compounds showed strong inhibition on the melanogenesis in B16 F1 mouse melanoma $(IC_{50}<1\;{\mu}g/ml)$. Due to the strong inhibitory activity and safety compared to current whitening agents such as arbutin, kojic acid and AHA, the compound can be a good candidate for new skin whitening agents.

• Journal of Ecology and Environment
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• v.33 no.3
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• pp.205-216
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• 2010

This research identified a disturbance regime caused by wild boar in a mature Quercus mongolica forest and analyzed the impact of this disturbance on the structure and distribution of herbaceous plants in Mt. Jeombong, Korea. We demonstrate that disturbance by wild boar was most frequent from winter to early spring, but also occurred year round. Areas which were frequently disturbed by wild boar included the mountain ridge, the mild slope on the north face, and sites with high concentration of Erythronium japonicum. The disturbance cycle by the wild boar in this region was estimated at approximately 2.8 years. The wild boar's reduced the community's species diversity and herbaceous coverage, and increased its evenness. This disturbance reduced the coverage of spring ephemeral; Veratrum nigrum var. ussuriense, Symplocarpus niponnicus, Anemone koraiensis and Corydalis turtschaninovii were particularly sensitive. In addition, summer green herbaceous plants such as Astilbe chinensis, Ainsliaea acerifolia, Meehania urticifolia, and Pimpinella brachycarpa were sensitive to the wild boar's. It was found that wild boar ate E. japonicum most selectively of all plants in this investigation area. In conclusion, together with micro-topography, wind, formation of gaps of a forest and rearrangement of litter layer, wild boar's disturbance is an important factor influencing the dynamic changes of an herbaceous community in a mature temperate hardwood forest.