• Korean Journal of Environment and Ecology
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• v.27 no.1
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• pp.99-112
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• 2013

This study aims to show the changes of characteristics of vegetation structure for 20 years(1991~2010) in Naejangsan National Park. As a result of analysis of actual vegetation, the mixed community of Quercus variabilis and Quercus serrata was distributed with 56.1%, and Q. variabilis community showed in southern steep slope with 17.6%. Pinus densiflora community(5.8%) was observed on the ridge and Carpinu tschonoskii community distributed in the slope of the valley with 6.6%. Zelkova serrata and Prunus sargentii community were distributed in valley. The classification by TWINSPAN, ordination by DCA considering importance percentage and property of vegetation class were divided into 4 communities, which are community I(P. densiflora-Q. variabilis community), community II(Q. variabilis community), community III(C. tschonoskii community) and community IV(Mixed deciduous broad-leaved trees community). The age of Pinus densiflora was 32years old and Q. serrata was 36 years old in the community I, that of Q. variabilis was 64 years old in the community II, Q. serrata was 46 years old and C. tschonoskii was 45 years old in the community III, and Acer palmatum was 54 years old and Cornus controversa was 47 years old in the community IV. As the result of Shannon's index of species diversity, the community Iwas ranged from 0.9751 to 1.4199, community II was ranged from 1.0765 to 1.3278, community III was ranged from 1.0353 to 1.2881, and community IV was ranged from 1.1412 to 1.3807. The change of vegetation structure analyzed through the comparison with results of studies carried out 20 years ago were natural selection of P. densiflora, expansion of Quercus spp. and increase of C. tschonoskii. Especially, A. palmatum is dominated by Q. variabilis in canopy layer like the result of study 20 years ago. A. palmatum was analysed by 14.6% in the canopy layer of only mixed deciduous broad-leaved trees community. As a result of analysis of habitat property of Q. variabilis and A. palmatum, Q. variabilis was distributed in dry area with the low value of pH, O.M., exchangeable cations and Avail. P, and A. palmatum was located in the wet valley with huge value of nourishment. The tendency of reduction of bio-diversity by Sasa borealis is same as previous study but, the distributed areas were reduced in Naejangsan area.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.603-617
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• 2018

This study surveyed the diversity and community characteristics of benthic macroinvertebrates and freshwater fish, which are the main animal classifications in a hydro ecosystem, from May to September 2017 in the western plains of the Demilitarized Zone (DMZ). The results showed a total of 125 species of benthic macroinvertebrates belonging to 66 families, 19 orders, and four phyla in the streams and wetlands. Among benthic macroinvertebrates, Coleoptera (27 spp.: 21.60%) was the largest group in terms of species richness followed by Odonata (26 spp.: 20.80%), non-Insecta (22 spp.: 17.60%), and Hemiptera (11 spp.: 8.80%) occupying in the lentic area. Of the feeding function groups (FFGs), predators (51 spp.: 56.67%) showed a relatively larger presence, indicating the dominance of hygrophilous invertebrates that usually inhabit the freshwater wetlands or ponds. Of the habitat oriented groups (HOGs), climbers (33 spp.: 24.44%) and burrowers (17 spp.: 12.59%) were the dominant groups. This observation is typical in a slow flowing habitat and can lead to the disturbance of the ecosystem due to cannibalism among predators. Cannibalism can be caused by stress induced by various population and environmental factors. For the ecosystem services benchmark (ESB) value, site 13 appeared to be the highest with 82 marks while other sites showed relatively lower rates and indices (III water quality class with ${\alpha}$-mesosaprobic). The analysis result of stability factors showed that almost all sites were evaluated to be the I characteristic group with high resilience and resistance or the III characteristic group that was sensitive to environmental disturbance and formed uneven and unstable communities. Of the freshwater fishes, 46 species (3,405 individuals) belonging to 39 families and 18 orders were identified in all the investigated sites. Among them, Cyprinidae (30 spp.: 65.2%) was the largest group, and Zacco koreanus was identified as the dominant species (728 individuals, 21.4%). The survey of freshwater fish communities found both stable communities (sites 7 and 13) with low dominant index (0.39) and high diversity index (2.29) and unstable communities (sites 2, 3, 8, and 10) in opposite tendency. This survey found five Korean endemic species, 17 species belonging to the export controlled species, two endangered species level II (Lethocerus deyrollei and Cybister chinensis), and rare species (Dytiscus marginalis czerskii) among benthic macroinvertebrates. The survey also found an invasive species, Ampullarius insularus, which was distributed throughout the whole area and thus can continuously disturb the ecosystem in the western plain area in the DMZ. Of freshwater fish, one natural monument (Hemibarbus mylodon) and three endangered species level II (Acheilognathus signifer, Gobiobotia macrocephalus, and G. brevibarba) were observed. The survey also found four introduced species (Pomacea canaliculate, Carassius cuvieri, Lepomis macrochirus, Micropterus salmoides) in the western DMZ area, indicating the need for the protection and conservation measures.

• Proceedings of the Ginseng society Conference
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• 1978.09a
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• pp.149-157
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• 1978

Ginseng is the English common name for the species in the genus Panax. This article gives a broad botanical review including the morphological characteristics, ecological amplitude, and the ethnobotanical aspect of the genus Panax. The species of Panax are adapted for life in rich loose soil of partially shaded forest floor with the deciduous trees such as linden, oak, maple, ash, alder, birch, beech, hickory, etc. forming the canopy. Like their associated trees, all ginsengs are deciduous. They require annual climatic changes, plenty of water in summer, and a period of dormancy in winter. The plant body of ginseng consists of an underground rhizome and an aerial shoot. The rhizome has a terminal bud, prominent leafscars and a fleshy root in some species. It is perennial. The aerial shoot is herbaceous and annual. It consists of a single slender stem with a whorl of digitately compound leaves and a terminal umbel bearing fleshy red fruits after flowering. The yearly cycle of death and renascence of the aerial shoot is a natural phenomenon in ginseng. The species of Panax occur in eastern North America and eastern Asia, including the eastern portion of the Himalayan region. Such a bicentric generic distributional pattern indicates a close floristic relationship of the eastern sides of two great continental masses in the northern hemisphere. It is well documented that genera with this type of disjunct distribution are of great antiquity. Many of them have fossil remains in Tertiary deposits. In this respect, the species of Panax may be regarded as living fossils. The distribution of the species, and the center of morphological diversification are explained with maps and other illustrations. Chemical constituents confirm the conclusion derived from morphological characters that eastern Asia is the center of species concentration of Panax. In eastern North America two species occur between longitude $70^{\circ}-97^{\circ}$ Wand latitude $34^{\circ}-47^{\circ}$ N. In eastern Asia the range of the genus extends from longitude $85^{\circ}$ E in Nepal to $140^{\circ}$ E in Japan, and from latitude $22^{\circ}$ N in the hills of Tonkin of North Vietnam to $48^{\circ}$ N in eastern Siberia. The species in eastern North America all have fleshy roots, and many of the species in eastern Asia have creeping stolons with enlarged nodes or stout horizontal rhizomes as storage organs in place of fleshy roots. People living in close harmony with nature in the homeland of various species of Panax have used the stout rhizomes or the fleshy roots of different wild forms of ginseng for medicine since time immemorial. Those who live in the center morphological diversity are specific both in the application of names for the identification of species in their communication and in the use of different roots as remedies to relieve pain, to cure diseases, or to correct physiological disorders. Now, natural resources of wild plants with medicinal virtue are extremely limited. In order to meet the market demand, three species have been intensively cultivated in limited areas. These species are American ginseng (P. quinquefolius) in northeastern United States, ginseng (P. ginseng) in northeastern Asia, particularly in Korea, and Sanchi (P. wangianus) in southwestern China, especially in Yunnan. At present hybridization and selection for better quality, higher yield, and more effective chemical contents have not received due attention in ginseng culture. Proper steps in this direction should be taken immediately, so that our generation may create a richer legacy to hand down to the future. Meanwhile, all wild plants of all species in all lands should be declared as endangered taxa, and they should be protected from further uprooting so that a. fuller gene pool may be conserved for the. genus Panax.

• Natural Product Sciences
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• v.8 no.1
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• pp.1-15
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• 2002

An International Cooperative Biodiversity Group (ICBG) program based at the University of Illinois at Chicago initiated its activities in 1998, with the following specific objectives: (a) inventory and conservation of of plants of Cuc Phuong National Park in Vietnam and of medicinal plants of Laos; (b) drug discovery (and development) based on plants of Vietnam and Laos; and (c) economic development of communities participating in the ICBG project both in Vietnam and Laos. Member-institutions and an industrial partner of this ICBG are bound by a Memorandum of Agreement that recognizes property and intellectual property rights, prior informed consent for access to genetic resources and to indigenous knowledge, the sharing of benefits that may arise from the drug discovery effort, and the provision of short-term and long-term benefits to host country institutions and communities. The drug discovery effort is targeted to the search for agents for therapies against malaria (antimalarial assay of plant extracts, using Plasmodium falciparum clones), AIDS (anti-HIV-l activity using HOG.R5 reporter cell line (through transactivation of the green fluorescent protein/GFP gene), cancer (screening of plant extracts in 6 human tumor cell lines - KB, Col-2, LU-l, LNCaP, HUVEC, hTert-RPEl), tuberculosis (screening of extracts in the microplate Alamar Blue assay against Mycobacterium tuberculosis $H_{37}Ra\;and\;H_{37}Rv),$ all performed at UIC, and CNS-related diseases (with special focus on Alzheimer's disease, pain and rheumatoid arthritis, and asthma), peformed at Glaxo Smith Kline (UK). Source plants were selected based on two approaches: biodiversity-based (plants of Cuc Phuong National Park) and ethnobotany-based (medicinal plants of Cuc Phuong National Park in Vietnam and medicinal plants of Laos). At mc, as of July, 2001, active leads had been identified in the anti-HIV, anticancer, antimalarial, and anti- TB assay, after the screening of more than 800 extracts. At least 25 biologically active compounds have been isolated, 13 of which are new with anti-HIV activity, and 3 also new with antimalarial activity. At GSK of 21 plant samples with a history of use to treat CNS-related diseases tested to date, a number showed activity against one or more of the CNS assay targets used, but no new compounds have been isolated. The results of the drug discovery effort to date indicate that tropical plant diversity of Vietnam and Laos unquestionably harbors biologically active chemical entities, which, through further research, may eventually yield candidates for drug development. Although the substantial monetary benefit of the drug discovery process (royalties) is a long way off, the UIC ICBG program provides direct and real-term benefits to host country institutions and communities.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.4
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• pp.192-198
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• 2015

Picophytoplankton, a group of tiny microorganisms of less than $3{\mu}m$, play an important role as a major primary producer in tropical open ocean as well as temperate coastal waters. Until now, more than 20 and 10 clades of Synechococcus and Prochlorococcus, respectively, have been identified in various marine environments, and its biogeographical distribution have been well studied as well as ecological niches of its major clades. To understand a distribution of diverse picocyanobacterial clades and environmental factors regulating their distribution, picocyanobacterial abundance and genetic diversity was investigated in adjacent waters of Dokdo showing diverse physical properties not only by seasonal variation but also by diverse physical processes. Synechococcus abundances were low in winter and then exponentially increased as water temperature increased up to $20^{\circ}C$. Above $20^{\circ}C$, the abundances tended to be saturated. On the contrary, Prochlorococcus was undetected or occupied a minor fraction of picocyanobacteria in most seasons. In summer, however, Prochlorococcus belonging to HLII ecotype occupied a significant fraction (up to 7%) of picocyanobacteria. In spring and early summer, the steep increase of Synechococcus abundances were resulted from growth of cold water-adapted Synechococcus belonging to clades I and IV. In summer, diverse Synechococcus clades including warm and pelagic water-favoring clade II tended to replace clades I and IV with maintaining high abundance. The water-column stability as well as temperature were found to be important factors regulating the Synechococcus abundances. Moreover, inflow and mixing of distinct water masses with different origins exerted significant influence on the composition of Synechococcus in the study area. Thus, physical processes as well as natural seasonal variation of environmental factors should be considered to better understand ecology of planktonic organisms around Dokdo.

• Korean Journal of Ecology and Environment
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• v.51 no.2
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• pp.160-167
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• 2018

The role played by reservoirs in the biogeochemical cycles of elements is a subject of ongoing debate. Recent research has revealed that reservoirs emit significant levels of greenhouse gases. To assess the importance of reservoirs in monsoon climate areas as a source of methane gas into the atmosphere, we investigated variations in organic carbon (OC) input into the reservoir, oxic state changes, and finally the amount of methane emitted (focusing on the ebullition pathway) in Lake Soyang, which is the largest reservoir in South Korea. Total organic carbon (TOC) concentrations were higher during summer after two years of heavy rainfall. The sedimentation rates of particulate organic carbon (POC) and particulate organic nitrogen (PON) were higher in the epilimnion and hypolimnion than the metalimnioin, indicating that autochthonous and allochthonous carbon made separate contributions to the TOC. During stratification, oxygen depletion occurred in the hypolimnion due to the decomposition of organic matter. Under these conditions, $H_2S$ and $CH_4$ can be released from sediment. The methane emissions from the reservoir were much higher than from other natural lakes. However, the temporal and spatial variations of methane ebullition were huge, and were clearly dependent on many factors. Therefore, more research via a well-organized field campaign is needed to investigate methane emissions.

• Journal of Life Science
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• v.24 no.11
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• pp.1244-1251
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• 2014

Platycodon grandiflorum (PG) has been known to possess many biological effects, including anti-inflammatory and anti-allergy activity and anti-obesity and hyperlipidemia effects. However, little research has been conducted regarding its anticancer effects, with the exception of its ability to stimulate apoptosis in skin cells. There has also been no study regarding PG-induced autophagy. The modulation of autophagy is recognized as one of the hallmarks of cancer cells. Depending on the type of cancer and the context, autophagy can suppress or help cancer cells to overcome metabolic stress and the cytotoxicity of chemotherapy. Therefore, the present study was designed to investigate whether or not extracts from PG-induced cell death were connected with autophagy and apoptosis in HCT-116 human colon cancer cells. PG stimulation decreased cell proliferation in a dose- and time-dependent manner and induced apoptosis, which was partially dependent on the activation of caspases. PG treatment also resulted in the formation of autophagic vacuoles simultaneously with regulation of autophagy-related genes. Interestingly, a PG-mediated apoptotic effect was further triggered by pretreatment with the autophagy inhibitors 3-methyladenin and bafilomycin A1. However, cell viability recovered quite well with bafilomycin A1 treatment. These findings show that PG treatment promotes both autophagy and apoptosis and that PG-induced autophagic response might play a role in the autophagic cell death of HCT-116 cells.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.151-160
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• 2018

Anoplophora chinensis and A. glabripennis is classified as important quarantine Cerambycidae beetles worldwide. These beetles cause serious damage on natural host plants and export bonsai trees in Korea. We evaluated efficacy of phosphine fumigant for control of two Cerambycidae beetles in bonsai. In the preliminary test to achieve CT (Concentration x time) values of phosphine to Cerambyicdae beetles larvae, we used Monochamus alternatus of larvae as an alternative insect. A 24 h phosphine fumigation with $2g/m^3$ phophine achieved 100% eggs mortality against Anoplophora chinensis and A. glabripennis. Larva of A. chinensis was also completely controlled when treated for 168-h at same dose desiccator. 100% mortality on larval stage of two beetle species were achieved both in dormancy (January) and vegetative period (February) of bonsai when treated with $2g/m^3$ phosphine. However, phosphine fumigation against vegetative period of Acer palmatum, Carpinus turczaninowii and Malus sieboldii bonsai showed slight phytotoxicity (shorten leaf and flower size and delayed flowering).

• Journal of Life Science
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• v.20 no.7
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• pp.977-982
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• 2010

We investigated the anti-cancer effects of two dibenzocyclooctadiene lignans, gomisin A and gomisin N, isolated from Schizandra chinensis Baill, in human promyelocytic U937 cells. Gomisin N, but not gomisin A, inhibited cell growth in a concentration-dependent manner, which was associated with the induction of G1 arrest of the cell cycle. G1 arrest induced by gomisin N was correlated with down-regulation of cyclin E, cyclin-dependent kinase (Cdk) 2 and Cdk4, and a concomitant up-regulation of Cdk inhibitors such as p16 (INK4A) and p21 (WAF1/CIP1). Furthermore, gomisin N inhibited phosphorylation of retinoblastoma protein (pRB) and p130, and expression of transcription factor E2Fs. The results indicated that growth inhibition by gomisin N is related to cell cycle arrest at G1 in U937 cells and these findings suggest that gomisin N may be a useful chemotherapeutic agent.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.192-201
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• 2019

While a fairly large amount of organic matter is produced daily via phytoplankton photosynthesis in Lake Paldang, South Korea, knowledge of the role of algal-derived organic matter (OM) as a refractory OM source is not adequate. To understand the contribution of algal-derived OM to the refractory pool, biodegradation experiment and $KMnO_4$ oxidation experiment were conducted for 60 days using $^{13}C$ and $^{15}N$ labeled natural phytoplankton assemblage. The assemblage was collected from Lake Paldang on May 20, 2010. The photosynthetically produced total organic carbon ($TO^{13}C$), particulate organic carbon ($PO^{13}C$), and particulate nitrogen ($P^{15}N$) remained at 26%, 20%, and 17% of the initial concentrations, respectively, in the form of non-biodegradable organic matter. In addition, 12% and 38% of $PO^{13}C$ remained after $KMnO_4$ treatment on Day 0 and 60, respectively. These results indicate that photosynthetic products could be an important source of refractory organic matter after microbial degradation. Moreover, the microbially transformed algal-derived OM could contribute to the oxidation rate of the chemical oxygen demand.