• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.360-364
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• 1996

Study on germination ratio and growth of lettuce affected by accumulated salt in vinyl house cultivation soils was investigated by pot test with EC 1.65. 3.50, 5.75. 7.15. 9.50 and 13.57 dS/m. (Germination rate of lettuce in different electric conductivity of 0, 2, 4, 6, 8 and 10 dS/m controlled with KCl were 96.7, 96.7, 87.8, 82.2, 52.2, and 27.8 % respectively. Standing ratio of lettuce in soil below 6 dS/m was more than 60% and in soils of 7.15, 9.50 and 13.57 dS/m they were 45, 32 and 31%, respectively. Growth and fresh weight of lettuces increased significantly in a low EC content soil. The fresh weight of lettuces in the soil of EC 3.50 dS/m was higher than that of the soil EC 1.65 dS/m by 22%, while another soils(EC: 5.75, 7.15, 9.50 and 13.57 dS/m) were decreased 3, 15, 60 and 62%, respectively. Relationship between soil EC and standing ratio of lettuce showed high correlation coefficient($r=-0.9057^{**}$). Therefore, in the field of vinyl houses concentrated salt, standing ratio of lettuce can be foreseen by soil EC [Y = -4.313x+ 82.95 (Y:standing ratio, x:soil EC)], also standing ratio and fresh weight of lettuce showed high correlation coefficient($r=0.8396^{**}$).

• Journal of Life Science
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• v.13 no.5
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• pp.658-667
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• 2003

Antioxidative enzymes (superoxide dismutase; SOD, ascorbate peroxidase; APX, glutathione reductase; GR) play major roles in scavenging mechanism of reactive oxygen species which were involved in various stress conditions including salt. In order to investigate the relation between their growth responses (dry weight) and the changes of antioxidative enzymes activity, salt-tolerant spinach beet having 15cm of shoot length were treated with various salt levels (0, 50, 200, 1000 mM NaCl) for 24 hours. Spinach beet exhibited an increase in the activity of antioxidative enzymes by salt, the maximal activity at 200 mM NaCl and the lowest activity at 50 mM NaCl in 2 hrs. after treatments. As a result of PAGE, it has been confirmed that spinach beet contained 3 isoforms (Fe-SOD, CuZn-SOD and Mn-SOD) of SOD and main isoform was CuZn- SOD form. In case of APX, isoforms of the low molecular weight(No. 7, 8) were showed strong expression especially at 200 and 400 mM NaCl treatment. Meanwhile, GR did not show specific pattern of isoforms among the salt treatments. Especially, in case of 50 mM treatment, plant showed the lowest activity of SOD with the best growth, a low enzyme activity was induced by inactivation of the Mn-SOD. Therefore, we suggested that the decrease of SOD activity at a low salt level (50 mM NaCl) or the increase of enzyme activity at a high salt level (200 mM NaCl) may be related to expression of the Mn-SOD isoform. These antioxidative enzymes showed the increase of activity in a short time by salt addition. So, it is considered that spinach beet copes effectively with a stressful condition such as salt by operating effective antioxidative defense mechanism rapidly under high salt level.

• Development and Reproduction
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• v.12 no.1
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• pp.57-66
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• 2008

Changes in luteinizing hormone (LH), serum testosterone (T), and salivary T levels with age were examined in Korean men. Serum was obtained from 167 Korean men of different ages ($20{\sim}69\;y$), and the serum LH and T levels were measured. Saliva samples were also obtained, and the salivary T level was determined. The LH levels did not change considerably until 40 y of age (20s, $2.5{\pm}1.0$; 30s, $2.7{\pm}1.5$; and 40s, $2.5{\pm}1.8\;mIU/mL$) but increased significantly around 50 y (50s, $3.7{\pm}1.8$ and 60s, $3.1{\pm}1.7\;mIU/mL$). Further, the serum T levels also did not change until 40 y of age (20s, $5.3{\pm}2.6$, 30s, $4.4{\pm}1.4$, 40s, $4.1{\pm}1.5\;ng/mL$) but decreased significantly at 50 y (50s, $3.4{\pm}1.5$; 60s, $2.6{\pm}0.8\;ng/mL$). The salivary T levels also showed small changes until the age of 40 y ($20s{\sim}40s$, $0.11{\pm}0.015\;ng/mL$) but decreased significantly at 50 y ($0.08{\pm}0.03\;ng/mL$). Thus, the relative ratio of salivary T to serum T levels did not change significantly in all the ages examined ($2.4{\pm}0.9%$). Linear regression analysis predicted that the LH levels increased 1.5%/y while the serum and salivary T levels decreased 1%/y and 0.8%/y, respectively. The serum T/LH ratio did not change considerably until the age of 40 y ($20s{\sim}40s$, $2.27{\pm}0.14$) but decreased significantly ($1.2{\pm}1.0$) at 50 y. Age-related changes in the salivary T/LH ratio were very similar to those in the serum T/LH ratio. These results demonstrated that LH and T levels in serum or saliva did not change considerably until 40 y of age; instead, in Korean men, from 50 y of age, the LH level increased, while the T level decreased. This suggests that primary testicular failure that occurred due to aging (approximately 50 y) and caused this phenomenon. The present study also shows that the salivary T level can be an indicator of the free T level in serum although the salivary T level correlates weakly with the total T level in serum (r=0.53). Thus, information regarding salivary T levels may be useful for studying the age-related changes occurring in male testicular physiology.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.3
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• pp.287-294
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• 2015

In this study, we investigated the antioxidative effects of brown seaweed Ecklonia cava extract and its subfractions. All experiments were performed with 50% ethanol extract, ethyl acetate fraction and aglycone fraction of E. cava. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activities ($FSC_{50}$) of ethyl acetate fraction ($FSC_{50}=6.98{\mu}g/mL$) and aglycone fraction ($7.03{\mu}g/mL$) are similar to that of (+)-${\alpha}$-tocopherol ($8.98{\mu}g/mL$) which is a reference control. Reactive oxygen species (ROS) scavenging activity (total antioxidant capacity, $OSC_{50}$) of the aglycone fraction ($OSC_{50}=14.48{\mu}g/mL$) on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system using the luminol-dependent chemiluminescence assay was the strongest among all extract and fractions. However, all samples showed lower antioxidant activities than that of L-ascorbic acid ($6.88{\mu}g/mL$) known as a powerful antioxidant. The protective effect of 50% ethanol extract on the $^1O_2$-induced cellular damage of human erythrocytes was dependent on the concentration from 5 to $50{\mu}g/mL$. Both ethyl acetate fraction and aglycone fraction showed strong cellular protective activities at $10{\mu}g/mL$, where the cellular protective effects (${\tau}_{50}$) of each fraction were recorded 442.0 min and 539.9 min, respectively. Three kinds of extract/fractions of E. cava showed much greater cellular protective activities at $10{\mu}g/mL$ than that of liposoluble antioxidant (+)-${\alpha}$-tocopherol (40.6 min) which is a reference control. These results suggest E. cava extracts and its fractions can be applied as an antioxidant ingredient in a field of cosmetics.

• Korean Journal of Ichthyology
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• v.17 no.3
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• pp.159-166
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• 2005

The karyotypes of three species of Gobiobotia in Korea were investigated: G. macrocephala, G. brevibarba, and G. nakdongensis. In these species, the mitotic chromosomes from 25 groups with two chromosomes each indicated that it is a diploid. The karyotypes of Gobiobotia macrocephala are 2n = 50 (9M+7SM+9ST) with NF = 100, G. brevibarba 2n = 50 (10M+7SM+4ST+4T) with NF = 92, and G. nakdongensis 2n = 50 (5M+9SM+9ST+2T) with NF = 96. Chromosome sizes ranged from 3.3 to $7.5{\mu}m$, 2.7 to $6.3{\mu}m$ and 3.5 to $7.3{\mu}m$ in length, respectively. This is the first report on the chromosomes of G. macrocephala and G. nakdongensis.

• The Korean Journal of Food And Nutrition
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• v.34 no.2
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• pp.181-186
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• 2021

Antioxidant properties and antioxidant activities were analyzed for water extracts and 50% and 70% ethanol extracts of the leaf of Angelica gigas Nakai. The polyphenol and flavonoid contents in water, 50%, and 70% ethanol extract of the leaf of Angelica gigas Nakai, it was found that the polyphenol contents were 18.75 mg GAE/g, 28.95 mg GAE/g, and 34.73 mg GAE/g, respectively, and flavonoid contents were respectively. The DPPH IC50 scavenging activity was 45.84 mg/mL, 36.44 mg/mL, 19.11 mg/mL, respectively, and theABTS+ radical scavenging ability (1 mg/mL) was 28.73%, 22.79%, and 12.70%, respectively. Tyrosinase inhibitory activity, 70% ethanol extract, 50% ethanol extract, and water extract 33.14%, and 4.53%, respectively. Nitrite scavenging activity, 70% ethanol extract, 50% ethanol extract, and water extract were in the order of 1 mg/mL scavenging activity, 36.43%, 34.80%, and 18.85%, respectively.

• Biomedical Science Letters
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• v.13 no.1
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• pp.39-45
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• 2007

Numerous psychological stressors playa role in development of the cardiovascular disease. The aim of this study was to determine whether a combined mental activity with experimental subway noise affects hematological physiology. Fifty-four healthy volunteers were divided group I which underwent subway noise (n=24) and group II which underwent a combined mental activity with subway noise (n=30). Venous blood samples were collected for measuring CBC, prothrombine time (PT), activated partial thromboplastine time (APTT), erythrocyte sedimentation rate (ESR), D-dimer and high sensitive C-reactive protein (H-CRP) levels before, 50 min of stress task (S-50m) and 60 min of recovery (R-60m). Changed ratios of granulocyte, lymphocyte, monocyte and platelet counts at S-50m and R-60m were higher in group II compared to group I. RBC count and hematocrit level in group I increased whereas those in group II decreased at S-50m. PT, APTT and ESR in the both groups were shortened at R-60m and the decreased ratios were high in group II compared to group I. H-CRP and D-dimer in the both groups were elevated at S-50m and R-60m while the increased ratios in group II were greater than those in group I. These observations imply that a combined mental activity with experimental subway noise may be a stressor which affects hematological physiology.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.1
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• pp.33-38
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• 2004

Melanin pigmentation in human skin is a major defense mechanism against ultraviolet light of the sun, but abnormal pigmentation such as freckles, liver spot could be a serious aesthetic problem. Nearly all studies are mainly concentrated on searching for the materials that have inhibitory activities on tyrosinase. In this work, to isolate phenolic compounds from Gastrodia elata, we purified the extract through solvent fractionation, column chromatography, and recrystallization. They were identified as 4-hydroxybenzyl alcohol 1, bis(4-hydroxyphenyl)methane 2, gastrodin (4-${\beta}$-D-glucopyranosyloxybenzyl alcohol) 3 on the base of spectroscopic evidences. In order to investigate their depigmentation effect, inhibitory activity against mushroom tyrosinase and inhibitory activity of melanin synthesis in B16 melanoma cells were evaluated in vitro. We have found that 4-hydroxybenzyl alcohol 1 and gastrodin (4- ${\beta}$-D-glucopyranosyloxybenzyl alcohol) 3 have no tyrosinase inhibitory activity, but inhibit the melanin synthesis in B16 melanoma cells. Tyrosinase inhibitory activities of bis(4-hydroxyphenyl)methane 2 (IC$\_$50/ = 400 $\mu\textrm{g}$/mL) and butanol fraction (IC$\_$50/ = 46 $\mu\textrm{g}$/mL) were lower/higher than that of arbutin (IC$\_$50/ = 114 $\mu\textrm{g}$/mL), but inhibitory activities of melanin synthesis in B16 melanoma cells were much higher than that of arbutin. Especially, tyrosinase inhibitory activities of isolated phenolic fraction (IC$\_$50/ = 2.37 $\mu\textrm{g}$/mL) from butanol fraction was very higher than that of arbutin (IC$\_$50/ = 114 $\mu\textrm{g}$/mL). Therefore, these results suggest that isolated phenolic compounds from Gastrodia elata have inhibitory activity against mushroom tyrosinase and inhibitory activity of melanin synthesis in 816 melanoma cells in vitro.

• Journal of the Korea Convergence Society
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• v.11 no.3
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• pp.253-261
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• 2020

The purpose of this study was to investigate the backstroke 100m race management ability of national swimmer with developmental disabilities. As a result of the study, first, he started slow to the first 50m phase and swam fast to the last 100m in 2015, however, he started fast to the first 50m phase and swam slow to the last 100m in 2016-2018. Second, the time of under water increased over the years, the distance and time of under water were the greater, and the speed of under water was the smallest in 2017. Third, the average of the distance during turn was 7.51 m, the time during turn was 4.34 sec, and the speed during turn was 1.73 m/s for four years. Fourth, the stroke efficiency during the first 50m phase increased over the years, and the stroke efficiency during the last 100m phase was greater in 2017. Based on this results, it is expected to be useful for training of swimmer with developmental disabilities.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.245-254
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• 1995

The density of ATP-sensitive potassium($K_{APT}$) channels, that open as intracellular ATP concentration falls below a critical level, is very high in skeletal muscle surface membrane and those high density may imply that $K_{ATP}$ channels have very important physiological roles. To elucidate a role of $K_{ATP}$ in relation to fatigue, the modulating effects of potassium channel openers and blockers on the fatigue velocity(FV) of mouse extensor hallucis longus muscle(EHL) were investigated in vitro. Twitch contraction was induced by an electrical field stimulation (EFS: 24-48V, 20ms, 0.2-4Hz) and resulting contraction force was isometrically recorded. The twitch forces were gradually decreased to 25% of initial contraction force(ICF) in $37.52{\pm}1.55sec$($mean{\pm}s.e.m.$, n=135), indicating the fatigue phenomena. The mean velocity for development of the fatigue was measured during the period that twitch force decreased to half($FV_{0/0.5}$) and during the period from half to 25%($FV_{0.5/0.25}$) of ICF. The fatigue was induced once every one hour and the tissue response was stable for up to 4 hours. In control condition, ICF was $5.8{\pm}0.12g$ (n=144) and decreased to 50% of ICF with the mean fatigue velocity of $0.182{\pm}0.006g/sec$($FV_{0/0.5}$, n=135) and from 50% to 25% of ICF with $0.084{\pm}0.004g/sec$($FV_{0.5/0.25}$, n=135). Cromakalim($50{\mu}M$) significantly increased $FV_{0.5/0.25}$(n=4). Glibenclamide($IC_{50}>50{\mu}M$), $Ba^{2+}$($IC_{50}=10{\mu}M$), 4-aminopyridine($FV_{0/0.5}$, $IC_{50}=0.5mM$; $FV_{0.5/0.25}$, $IC_{50}=2mM$) decreased both $FV_{0/0.5}$ and $FV_{0.5/0.25}$ concentration-dependently up to 75%. $TEA^+$(30mM), E-4031($10{\mu}M$), tolbutamide(1mM) decreased $FV_{0.5/0.25}$, but apamin(300nM) and $TEA^+$(10mM) showed no significant effects. Our results suggest that activation of the $K_{ATP}$ channels may be major cause of $K^+$ outflux during development of the fatigue and the isolated EHL muscle could be an useful experimental preparation in studying the fatigue phenomena in skeletal muscle. In addition, the possibility of activation of delayed rectifier during the fatigue development remains to be studied further.