Medicinal plants were screened for the inhibitory effects on human immunodeficiency virus type 1 pretense. Of the extracts tested, the strong inhibitory effects were observed in the acetone extracts of the pericarp of Camellia japonica. Camelliatannin H from the pericarp of C. japonica showed a potent inhibitory activity on HIV-1 pretense. Effects of the extract and compound from leaves of Zanthoxylum piperitum on the enzyme activities were investigated in the liver of bromobenzene-treated rats. The methanol extract and protocatechuic acid isolated from Z. pipetitum reduced the activity of aniline hydroxylase that increased by bromobenzene, while did not affect the activities of aminopyrin N-demethylase and glutathione S-transferase. The extract and protocatechuic acid recovered significantly the activity of epoxide hydrolase decreased by bromobenzene.

The wild Pyrus plants belong to the deciduous woody plants in Rosaceae family. Most are cultivated for fruit productions, but some for ornamental plants. There are 5 Pyrus species including Pyrus ussuriensis and 8 varieties cultivated in Korea. In Korea, these plants are populated near villages or on the hills, and they are easily propagated since their fruit are very juicy and quite big in size. Plant breeding to get improved cultivars is not difficult because the Pyrus plants are easy to cross breeding among its genus. Because not only this reason but there have been shown lots of variation in wild groups, the Pyrus plants inhabited in Korea are excellent deciduous woody plants and favorable fruit trees to develop ornamental plants. It is necessary to develop many kinds of fruit trees and ornamental trees containing genetically different character, so that it will be satisfied for many different people's taste and demands. Collecting lots of wild plant resource with diverse genes is necessary for plant breeding.

Four major naturally populated areas around the Jindong valley in Inje-Gun, Gangwon province for wild Pyrus ussuriensis, Malus sieboldii, and Malus baccata are mostly located on the southeast side of the mountains at 630-745m in altitude at sea level and are in very good sunny areas. The total of 77 taxa dividing into 32 families, 58 genera, 65 species, and 12 varieties has been inhabited in these areas. Most of these plants are heliophytes, which love sunshine, but some of rhizo-plants such as Sasa borealis, climbing plants such as Actinidia arguta and Celastrus orbiculatus, or naturalized plants like Bidens frondosa are also shown. These areas have been continually destroyed, so it is possibly thought that the second transition has been progressed. The index of species diversity of plant groups in these areas is 0.672∼1.465 based on the Shannon-Wiener's method, but its index for the area that rhizo-plants like Sasa borealis are growing as an under planting decreases relatively. In this study, the oldest plant of Pyrus ussuriensis in Korea, which is 120cm in diameter at breast height (DBH), 19m in tree height and 25m in width, has been found.