• Journal of Ecology and Environment
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• v.29 no.6
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• pp.565-572
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• 2006

This study examined the decomposition of blades and culms of aquatic emergent plant species, Zizania latifolia, Phragmites communis and Typha angustata, which were the most frequent in Lake Paldang. The experiment was carried out from July to December, 2005 in fresh water of lake Paldang using litter bag method. The litter bags had 1.2 mm mesh size and were suspended at 1 m depth of water surface. Remaining mass of blades and culms of each species after 97 days was 21.2% and 22.6% of initial mass in Z. latifolia, 32.5% and 56.4% in P. communis and 44.7% and 38.1 % in T. angustata, respectively. The plant tissue having high N concentration and low C/N exhibited the faster decay rate than the others. However, the tissue of high content of lignin, cellulose, lignin:N, and cullulose:N showed a slow decomposition rate. Water temperature was the most effective environmental factor on the emergent macrophyte litter decomposition in aquatic ecosystems. According to the water temperature, DO, $NO_3^-$-N, and total phosphate concentration were changed in the linear way. The mass loss of plant tissue of emergent macrophytes showed positive relationship with P concentration in water. The experiments on the decomposition of the litter using different mesh sized litter bag did not show significant differences between them. The results suggest that the decomposition of emergent macrophytes in fresh water of lake Paldang, which showed features of lentic and lower part of a stream, was affected by microbial activities better than the micro-invertebrates such as shredders.

• Korean Journal of Plant Resources
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• v.20 no.3
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• pp.234-241
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• 2007

The present study was undertaken to classify and describe the riparian vegetation of the 6 river${\cdot}$stream of Korea Peninsula. As a result the vegetation was divided into nineteen communities. The vegetation units obtained in the present study were as follow: A: Salix koreensis community, B: Salix gracilistyla community, C: Robinia pseudo-acacia community, D: Amorpha fluticosa community, E: Brousonnetia papyrifera community, F: Phyllostachys bambusoides community, G: Rubus corchorifolius community, H: Phramities japonica community, I: Phramites communis community, J: Miscanthus sacchariflorus community, K: Miscanthus sinesis var. purpurascens community, L: Artemisia princeps var. orientalis community, M: Humulus japonicus community, N: Zoysia japonica community, O: Inperata cylindrica var. koenigii community, P: Agropyron tsukushiense var. transiens community, Q: Juncos effusus var. decipiens community, R: Rumex crispus community, S: Persicaria hydropiper community. The vegetation characteristics of riversides was recovered in the surveyed results according to river${\cdot}$stream basin, in other words, 10 communities in the upper river${\cdot}$stream riparian, 15 communities in the middle river${\cdot}$stream riparian, 10 communities in the down river${\cdot}$stream riparian. The Phragmites japonica community in the upper and Phragmites communis community in the down was analyzed by common community of the 6 river${\cdot}$stream riparian, respectively, but none in the middle. The standing profile of vegetation across 6 river${\cdot}$stream was seen stepwise Phragmites japonica community, Salix gracilistyla community, Miscanthus sinensis var. purpurascens community, shrub community by natural waterway in the upper, Salix gracilistyla community, Phragmites communis community, Rumex crispus community, Miscanthus sacchariflorus community, Humulus japonicus community in the middle, Phragmites communis community in the down. The differences of distributional featurs of vegetation emerged from the riparian of the 6 river${\cdot}$stream, but don't from the 6 river${\cdot}$stream.

• Korean Journal of Plant Resources
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• v.33 no.6
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• pp.604-614
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• 2020

Chronological aging and photoaging affect appearance, causing wrinkles, pigmentation, texture changes, and loss of elasticity in the skin. Phragmites communis is a tall perennial herb used for its high nutritional value and for medicinal purposes, such as relief from fever and vomiting and facilitation of diuresis. In this study, we investigated the effects of ethanol extract of P. communis rhizome (PCE) on skin aging. The total flavonoid and total phenolic content in PCE were 2.92 ± 0.007 ㎍ of quercetin equivalents (QE) and 231.8 ± 0.001 ㎍ of gallic acid equivalents (GAE) per 100 mg of dried extract (n = 3). The half-maximal inhibitory concentration (IC50) values of PCE for 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and hydrogen peroxide scavenging activities were 0.96 and 0.97 mg/mL, respectively. PCE showed inhibitory effects on tyrosinase when L-tyrosine (IC50 = 1.25 mg/mL) and L-3,4-dihydroxyphenylalanine (IC50 = 0.92 mg/mL) were used as substrates. PCE treatment up to 200 ㎍/mL for 24 h did not cause any significant cytotoxicity in B16F10 melanocytes, human dermal fibroblasts (HDFs), and HaCaT keratinocytes. In B16F10 melanocytes, PCE (25 and 50 ㎍ /mL) inhibited melanin production and cellular tyrosinase activity after challenge with α-melanocyte-stimulating hormone (α-MSH; p < 0.05). In HDFs, PCE suppressed the mRNA expression of matrix metalloproteinase-1 (MMP-1) and reduced the activity of elastase (p < 0.05). In addition, ultraviolet B (UVB)-mediated downregulation of hyaluronic acid synthase-2 gene expression in HaCaT keratinocytes was also effectively suppressed by PCE treatment. Overall, our results showed that PCE has potential anti-skin aging activity associated with the suppression of hyperpigmentation, wrinkle formation, and reduction in dryness. PCE is a promising candidate for the development of an anti-skin aging cosmetic ingredient.

• The Korean Journal of Ecology
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• v.23 no.2
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• pp.157-161
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• 2000

Mass loss and changes of mineral nutrients during decomposition of Phragmites communis for 13 months from November 1998 to December 1999, were investigated at the fringe of stream at Boryeong, Chungnam Province in Korea. Plant materials, which were collected in November 1998. were divided into leaves, culms and rhizomes. Litterbags, 15${\times}$15 cm, were made of nylon mesh with 2-mm$^2$ holes. At 13 months after installation, remaining mass of leaves, culms and rhizomes was 29.0%, 57.4%, 20.6%, respectively. Mass loss rate of the culms was significantly lower than those of the leaves and rhizomes. The decay rate of leaves, culms and rhizomes was 1.21. 0.42 and 1.48 per year, respectively. Initial concentration of N, P, K, Ca and Mg of leaves. culms and rhizomes was 22.5, 9.0, 15.5 mg/g for N, 0.34. 0.10, 0.33 mg/g for P, 15.0, 12.5. 12.3 mg/g for K, 2.84. 0.80, 0.03 mg/g for Ca. 1.94. 0.97, 0.40 mg/g for Mg, respectively. Concentrations of nutrients were higher in leaves than in culms and rhizomes. Except for N and Mg in rhizomes, there was no immobilization period during the decomposition. In the case of remaining K and Ca, most are lost during the first 3 months. Without any suitable method for removal of dead part, eutrophication of freshwater may be accelerated by dead macrophytes.

• Korean Journal of Environmental Agriculture
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• v.25 no.2
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• pp.147-156
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• 2006

This study was conducted to investigate natural distribution of aquatic plane and to find out natural aquatic plants which highly absorb nutrient N and P. We surveyed vegetation within ${\pm}2m$ from streamside in 12 tributaries of the West Nakdong river watershed during May to October in 2003. Hydrophytes surveyed in tributaries of the West Nakdong river watershed were 27 families, 61 genera, 76 species, 3 varieties. Major dominance species of aquatic plants were Z. latifolia, P. communis, P. thunbergii, P. arundinacea, P. japonica, and P. distichum var. indutum. Aquatic plants having high production ability of biomass were Z. latifolia, P. communis, P. arundinacea, P. japonica, and E. crus-galli var. echinata. In the vertical distribution of hydrophytes within streams, dominant species were P. thunbergii and P. japonica in the upper stream, but dominant species in the downstream were P. communis and Z. latifolia. Species diversity or aquatic, plants was reduced, but their biomass and nutrient (T-N and T-P) content per the natural area unit $(m^2)$ were increased in the downsteaam. Nutrient N and P content of aquatic plants per the natural area unit were high at Joman river, Pyeonggangcheon, Bulam drainage canal, and Hogyecheon. Fifty-seven species of aquatic plants having high biomass were grounped into 4 categories $(I{\sim}IV)$ according to their nutrient content per dry weight unit. I group $(T-N,\;\geqq20gkg^{-1}\;&\;P_2O_5,\;\geqq7gkg^{-1})$ was comprised of 3 submerged plants (H. verticillata, P. crispus, and C. demersum), e emergent plants (O. javanica, P. distichum var. indutum, and R. sceleratus), 1 suspended plant (T. japonica), and 1 riparian plant (A. lobatum). Otherwise, in classification of natural hydrophytes according to their nutrient content per natural area unit, Z. latifolia, P. communis, P. longiseta, P. arundinacea, and P. distichum var. indutum possessing great biomass productivity as emergent plants were included in I group $(T-N,\;\geqq1gm^{-2}\;&\;P_2O_5,\;\geqq0.7gm^{-2})$.

• Journal of Environmental Science International
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• v.4 no.4
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• pp.15-15
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• 1995

ABA and SA showed different effect on stomatal closing on same condition. The addition of 1 M salicylic acid to fully opened stomata resulted in a significant reductionn of 22 % in stomatal aperture. However, 1 mM ABA reduced 73 % of stomatal aperture. The light absorption spectra of the salicylic acid solution showed that SA was degraded within 1 hour. Therefore, SA solution was resupplied % the detached epidermis every 30 min. during incubation and it was found that even at 10 $mu$M SA induced stomatal closing significantly. Its effect was also greatly pH dependent. The reduction of stomatal aperture caused by 1 mM SA was most effective at lower pH (pH 7.2, 5 %: pH 6.2, 40 %; pH 5.2, 78 %). Therefore, if SA was properly treated to the epidermal strips in the medium, the effects of SA on stomatal closing were similar with those of ABA.

• Journal of Environmental Science International
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• v.4 no.4
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• pp.317-321
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• 1995

ABA and SA showed different effect on stomatal closing on same condition. The addition of 1 M salicylic acid to fully opened stomata resulted in a significant reductionn of 22 % in stomatal aperture. However, 1 mM ABA reduced 73 % of stomatal aperture. The light absorption spectra of the salicylic acid solution showed that SA was degraded within 1 hour. Therefore, SA solution was resupplied % the detached epidermis every 30 min. during incubation and it was found that even at 10 $\mu$M SA induced stomatal closing significantly. Its effect was also greatly pH dependent. The reduction of stomatal aperture caused by 1 mM SA was most effective at lower pH (pH 7.2, 5 %: pH 6.2, 40 %; pH 5.2, 78 %). Therefore, if SA was properly treated to the epidermal strips in the medium, the effects of SA on stomatal closing were similar with those of ABA.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.2
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• pp.109-116
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• 2012

This study was carried out to determine the forage quality, production, and regrowth of Phragmites communis as a native grass according to growth stages. Experiment 1 was conducted in Ansan from May 2009 to April 2010 (7 stages), and experiment 2 was conducted in Cheonan from May to November 2011 (10 stages). In experiment 1, forage quality decreased rapidly with advance of growth from May. When harvested on late May, July, September and April of the following year, the contents of crude protein were 7.7%, 4.6%, 3.7%, and 2.2%, respectively. Relative feed value (RFV) were 80.2, 65.1, 61.8 and 52.8, and lignin contents were 7.1%, 9.9%, 12.0%, and 13.2%, respectively. In experiment 2, significantly higher forage yields were observed when harvested from late June to mid July. On the other hand, forage quality decreased with delayed harvest as was in experiment 1. Good regrowth of Phragmites communis was observed when harvested earlier than in August. When harvested on late May, June, July, August, September, October and November, the dry matter (DM) yields were 7,329 kg/ha, 12,527 kg, 9,593 kg, 8,279 kg, 7,649 kg, 5,822 kg and 5,540 kg, and in vitro digestible DM (IVDDM) yields were 3,924 kg/ha, 5,264 kg, 4,273 kg, 3,322 kg, 3,352 kg, 2,195 kg and 1,887 kg, respectively. Forage quality grades of Phragmites communis were 4th grade in May, 5th grade from June to Sept., and 6th grade in Oct., Nov., or in Apr. of the following year. However, all regrown Phragmites communis ranked the 4th in quality. In conclusion, we recommend that Phragmites communis should be harvested from late June to mid July (no later than the end of July) to obtain good forage quality with digestible nutrient contents greater than rice straw. Regrowth of Phragmites communis was poor, and more than 70% of annual forage yields were out of the first harvest. Therefore, we recommend only one harvesting per year for good regrowth and stable production of Phragmites communis.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.3
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• pp.303-307
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• 1996

The degree of autolysis and presence of cell-wall degrading enzymes in an anaerobic ruminal fungus, Piromyces communis OTSI, grown in liquid medium, was monitored to evaluate the effect of self-digestion on fungal biomass. After a 30 days incubation period fungal dry weight decreased by 45% and the cell wall component chitin decreased by 22%. Chitinase activity detected in the supernatant was mainly of the endotype and peaked at day 6 of the incubation. ${\beta}-1$, 3-glucanase was detected from day 4 and increased throughout the incubation period. Autolysis was a slow process, and under natural conditions it is unlikely that it plays a significant role in the degradation of the spent fungal vegetative stage in the rumen.

• Journal of Life Science
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• v.11 no.2
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• pp.111-120
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• 2001

The pathological aspects of purified ricin from the seeds of the castor oil plant, Ricinus communis, were examined, using light and transmission electron microscopy. ICR mice were exposed to ricin by peritoneal injection with 100 ng/1 $m\ell$ PBS(pH 7.0) mouse and histological observations on the liver, spleen, thymus, lung and heart were carried out at intervals up to 48 h after exposures. All the organs examined were damaged by ricin. Among the organs, the spleen and thymus; immune organs were the most sensitive to ricin, whereas the effect delayed in the liver, lung and heart. Furthermore, the immune cells in each organ were the most sensitive to ricin. Accordingly, the effect of ricin on the organs seems to be affected by the immune cells existed in each organ, In each organ, the immune cells showed apoptotic changes, while the capillary endothelial and parenchymal cells showed necrotic changes.