• Ocean Science Journal
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• v.40 no.2
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• pp.61-66
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• 2005

Benthic amphipod, Grandidierella japonica widely inhabits the Korean coastal waters and is developed as a standard test species for sediment toxicity tests. We exposed G. japonica to various pollutants including 4 kinds of inorganic metals (Ag, Cd, Cu and Hg), tributyltin [TBT], ammonia and 7 polycyclic aromatic hydrocarbon (PAH) compounds (acenaphthene, chrysene, fluoranthene, fluorene, naphthalene, phenanthrene and pyrene) to estimate the no observed effect concentration (NOEC) and the median lethal concentration (LC50) of each pollutant during the 96-hour acute exposure. Among all tested pollutants, TBT was most toxic to G. japonica, and Rg was most toxic among inorganic metals. The toxicity of pyrene to G. japonica was greatest among PAH compounds, followed by fluoranthene, phenanathrene, acenaphthene, fluorene and naphthalene. The toxicity of PAH compounds was closely related to their physico-chemical characteristics such as $K_ow$ and water solubility. G. japonica responded adequately to pollutant concentrations and exposure durations, and the sensitivity of G. japonica to various inorganic and organic pollutants was generally comparable to other amphipods used as standard test species in ecotoxicological studies, indicating this species can be applied in the assessment of environments polluted by various harmful substances.

• Korean Journal of Plant Taxonomy
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• v.38 no.2
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• pp.111-120
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• 2008

Taxonomic identities of Utricularia japonica and U. tenuicaulis were examined. Utricularia japonica was differed from U. tenuicaulis by having a scape narrower than the stem, rather sparsely arranged leaves, and more or less oblong leaves. Utricularia japonica has been known to occur widely in Korea due to the misidentification of U. tenuicaulis, which is distributed widely in southern and middle Korea. However, only one population of U. japonica was found in Chunjin Lake, near Kosung-gun, Kwangwon-Do, in Korea.

• Asian Journal of Turfgrass Science
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• v.11 no.4
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• pp.281-288
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• 1997

This study was performed to find out the mineral cycles of sulphur in dynamic grassland ecosystems in a steady state condition at the northwest side on Mt. Kwanak. The experimental results may be summarized on the communities of a Zoysia japonica and a Miscanthus sinensis as follows. As compared with some properties of the surface soils among two semi-natural grasslands, sulphur war greater quantity in a Miscanthus sinensis than in a Zoysia japonica on Mt. Kwanak . For the case of steady production and release, the raion of annual mineral production to the amount accumulated on the top of mineral soil in a steady state provides the estimates of release constant k. The release constants on sulphur of the litter were 0.54 in a Zoysia japonica and 0.36 in a Miscanthus sinensis grassland. The half times of S required for the release or accumulation of the litter on the grassland were 1.28 years in a Zoysia japonica and 1.93 years in a Miscauthus sinensis The amounts of annual cycles for sulphur in the grassland ecosystem under the steady-state conditions were 20.65g /$m^2$ in a Zoysia japonica and 26.28g /$m^2$ in a Miacanthus sinensis grassland. Key words: Zoysia japonica Miscanthus sinensis Mt. Kwanak, Sulphur, Mineral cycles.

• YAKHAK HOEJI
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• v.50 no.6
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• pp.421-428
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• 2006

Water extracts, ethanol extracts, and juice of Cusuta japonica, C, australis, and C. chinensis were prepared, and their cytotoxicity, antioxidant activity and inhibitory effects on tyrosinase activitiy and melanin biosynthesis were estimated by using melanoma Clone M-3. From this study; the following conclusions were attained. Extracts of Cuscuta japonica, C. australis, and C. chinensis showed noticeable cytotoxicity except ethanol extracts from the stem of C. australis. A maximual cytotoxicity was observed with tile ethanol extract from the seed of C, australis (87.39%). While the ethanol extract from the seed of C. japonica (91.88%) showed the most pronounced inhibitory effect on melanin biosynthesis, the water extract from the stem of C. japonica (1.05%) possessed very little inhibitory effect. The most inhibitory effect on tyrosinase activity was observed with the water extract from the stem of C. australis (76.67%). Howeverr the water extract from the stem of C. japonica showed a very poor effect on the inhibition of tyrosinase activity All the preparations, except extracts from the seed of C. australis were able to remove reactive oxygen species (ROS) in a dose-dependent manner. The juice of C. japonica demonstrated the strongest activity (59.02%).

• Korean Journal of Pharmacognosy
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• v.52 no.4
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• pp.212-218
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• 2021

Fatsia japonica is grown wild to Eastern Asia, including Korea, Japan, and Taiwan and it is known as ornamental plant, and it is also known that pharmacological action. In this study, we have selected the stem of F. japonica with consideration about biological activities and amount of yield. In addition, four compounds (1-4) were isolated from the stem of F. japonica. Extensive spectroscopic and chemical studies established the structures of these compounds as maltose (1), begoniifolide A (2), leiyemudanoside B (3), leonticin F (4). All of the compounds were investigated for their anti-inflammatory, anti-neuroinflammatory, and neuro-protective effects on RAW264.7, BV2, and HT22 cells. However, among four compounds, there were no effects by maltose (1), begoniifolide A (2), leiyemudanoside B (3), leonticin F (4) on the anti-inflammatory, anti-neuroinflammatory, and neuro-protective action. This is the first report on the isolation of maltose (1), begoniifolide A (2), leiyemudanoside B (3), leonticin F (4) from the stem of F. japonica. Begoniifolide A (2), leiyemudanoside B (3), leonticin F (4) were isolated for the first time from this plant. It might be necessary to continue the further studies to find the biological active compounds isolated from the stem of F. japonica.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.2 s.121
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• pp.49-54
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• 2007

This research was performed to investigate the effect of formaldehyde removal and confirm the utility of plants as indoor environment improvement systems. The plant materials used in this study were Fatsia japonica, Ardisia japonica, Ardisia pusilla and Davallia mariesii. Plants were placed in an airtight chamber under artificial formaldehyde. The initial formaldehyde concentration in the chamber was $500{\pm}30ppb$, and the conditions of $1,500{\sim}2,000lux$ light, $25{\pm}5^{\circ}C$ temperature and $80{\sim}90%$ humidity were maintained. Each chamber was treated as no plant, plant-only and Plant+soil. The total leaf number for Davallia mariesii, Ardisia japonica, Ardisia pusilla, and Fatsia japonica was 40.8, 48.6, 62.3, and 11.8 respectively. The total leaf space n of those plant materials were $2,385cm^2,\;1,252cm^2,\;2,468cm^2\;and\;1,262cm^2$ respectively. The formaldehyde concentration was reduced to $80{\sim}90%$ of the initial concentration in plant-only and Plant+Soil treatment chamber of all species in 12 hours. In the plant-only chamber, Fatsia japonica had removed formaldehyde density by 95% after 12 hours while Ardisia japonica had removed 90%. In the case of Ardisia pusilla, the early removal rate was higher in the plant-only treatment chamber than the Plant+Soil treatment chamber. The formaldehyde removal rate of Davallia mariesii was 98% after 12 hours. In the Plant+Soil treatment chamber, the amount of removal of formaldehyde per time of Davallia mariesii, Ardisia japonica, Ardisia pusilla, and Fatsia japonica was 20.42ppb/hr, 16.28ppb/hr, 2.5.42ppb/hr, 10.28ppb/hr respectively. In the plant-only, That was 22.50ppb/hr, 20.97ppb/hr, 20.83ppb/hr, 20.97ppb/hr respectively.

• Journal of Environmental Science International
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• v.23 no.9
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• pp.1563-1572
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• 2014

The autecology of the Zostera marina and Z. japonica was studied in populations growing in the same locality (Sagumi Bay, southwestern coast of Korea). Environmental factors and plant characteristics were examined monthly from August 2008 to September 2011. Along intertidal zone, Z. japonica (0.1-0.5 m above mean lower low water, MLLW) occurred above Z. marina (0.5-2.5 m MLLW). Tidal exposure at low tide during day was the highest in the spring and the lowest in the summer. Underwater Irradiance showed seasonal fluctuation that was the highest in spring and summer caused by tidal pattern. Strong seasonal patterns in water temperature appeared to control the seasonal variations in morphology, biomass and leaf growth. The seasonal pattern of Z. japonica resembled that of the Z. marina in morphological characteristics, above-and below-ground biomass, whereas it differed in shoot density and leaf elongation. Despite some similarities in seasonal growth patterns, the patterns of Z. japonica were lagged by 2 month of Z. marina. Seasonal variation in the above biomass of Z. marina was caused by changes in density and plant size, whereas that of Z. japonica was mainly caused by changes in shoot density. Zostera marina was more sensitive to high temperatures than Z. japonica, and the increasing water temperature during the summer became the factor that inhibits the growth of the Z. marina. Zostera Japonica, there is no clear change according to the amount of the light. It is because its habitat locates above that of Zostera marina so that the amount of the light that is necessary to growth is enough and in this condition, any preventing factor does not seem to work at all. Although underwater light getting into Zostera marina's habitat is very low level and there is no any hindrance to the survival of them, it prevents them from their productivity a bit.

• Korean Journal of Environment and Ecology
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• v.8 no.1
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• pp.27-42
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• 1994

Vegetational structure and successional sere were investigated for evergreen broad-leaved forest in Hongdo. Forty-nine plots were classified into six groups, which are Camellea japonica community, Machilus thunbergii community, Castanopsis cuspidata var. sieboldii-Machilus thunbergii community, Castanopsis cuspidata var. sieboldii community, Castanopsis cuspidata var. sieboidii-Camellea japonica community and evergreen broad-leaved mixed community by the DCA ordiantion and TWINSPAN techniques. Successional sere of the forest vegetation in the surveyed area were proceeding from Pinus densiflora through Castanopsis cuspidata var. sieholdii to Neolitsea sericea, Dendropanax morbifera, Machilus japonica, Quercus acuta and Mahilus thunbergii in the canopy layer group and from Ligustrum japonicum, Ardisia japonica. Eurya japonica. Rhaphiolepsis umbellata through Trachelosperum asiaticum, Kadsura japonica. Litsia Japonica, Camellea japonica to Aucuba japonica, Euscaphis japonica, Ficus erecta in the understory and shrub layer group.

• Journal of Plant Biology
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• v.38 no.2
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• pp.173-180
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• 1995

We investigated levels and distribution of genetic variation in Korean populations of Calystegia soldanella and C. japonica, clonally reproducing herbaceous perennials. Calystegia soldanella is one ofecologically important beach plants growing only on sand and beach dunes in Europe, East Asia, the Pacific Islands, and the west coast of North America. In contrast, C. japonica usually grows on small mounds of paddy fields, roadsides, and waste places with patchy distribution. Starch gel electrophoresis was conducted on leaves collected from 13 populations of C. soldanella and eight populations of C. japonica. The levels of genetic variation of the two species are very comparable; means of expected heterozygosity (Hep) were 0.100 and 0.099 for C. soldanella and C. japonica, respectively. These values were also very similar to those for species with similar life-history and ecological traits. However, the proportion of total genetic diversity partitioned among populations (GST) of C. soldanella (0.146) was considerably lower than that of C. japonica (0.383). In addition, means of Nei's genetic identity (Ⅰ) for C. soldanella and C. japonica were 0.985 and 0.900, respectively, which supports a restricted gene flow resulting from obligate clonal reproduction of C. japonica. Significant differences in allele frequency were detected among populations at eight and nine of nine polymorphic loci for C. soldanella and C. japonica (P<0.01), respecitvely. Considering the ecological importance of C. soldanella, the isolated beach populations coupled with present destruction of natural habitats of the species may result in erosion of genetic diversity in the near future. In this respect, conservation efforts should be focused on those populations that currently maintain the most genetic diversity such as those populations in the eastern and southeastern Korean Peninsula and Hamduck Beach, Cheju Island.

• Korean Journal of Plant Taxonomy
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• v.50 no.4
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• pp.385-394
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• 2020

To elucidate the molecular phylogeny of Neottia japonica, which is a terrestrial orchid distributed in East Asia, the internal transcribed spacer (ITS) of nuclear DNA and the matK of chloroplast DNA were used. A total 22 species of 69 accessions for ITS and 21 species of 114 accessions for matK phylogeny were analyzed with the maximum parsimony and Bayesian methods. In addition, we sought to establish a correlation between the distribution, morphology of the auricles and genetic association of N. japonica with phylogenetic data. The phylogenetic results suggest that N. japonica is monophyletic and a sister to N. suzukii in terms of the ITS phylogeny, while it is paraphyletic with N. suzukii in terms of the matK phylogeny. N. japonica and N. suzukii show similar morphologies of the lip and column, they both flower in April, and they are both distributed sympatrically in Taiwan. Therefore, it appears to be clear that N. japonica and N. suzukii are close taxa within Neottia, although there is incongruence between the nrDNA and cpDNA phylogenies of N. japonica. The incongruence between the two datasets may have various causes, meaning that further studies are needed to confirm the evolutionary process of N. japonica. The phylogenetic status of N. kiusiana, which was not included in previous studies, was as a sister to N. nidus-avis. Meanwhile, the ITS and matK phylogenies are unsuitable for identifying genetic associations with the characteristic of auricles. The phylogenetic topologies of Korean, Taiwanese and mainland Chinese individuals suggest that the populations of N. japonica in Korea originated from China's mainland and island areas. The characterization of regional gene differences could provide useful preliminary data for future studies.