• Korean Journal of Agricultural Science
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• v.21 no.2
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• pp.122-132
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• 1994

Bacteriostatic activity of secretory immumoglobulin A (SIgA) in human and bovine colostrums on enterotoxigenic type Salmonella was tested in the tissue culture medium. SIgA was used in $0.1{\sim}5.0mg/m{\ell}$ concentration with or without the addition of egg lysozyme tested for theirs bacteriostatic activites. 1. Bovine SIgA rich fraction with a large amount of $IgG_1$-dimer could be prepared from bovine colostrum of Holstein cows by anion exchange chromatography using DEAE-Sephadex A-50 and gel filtration on Sephadex G-200 and Sepharose 6B. 2. Human SIgA appeared to be the most bacteriostatic effect for all varieties of Salmonella in a range of $0.5{\sim}1.0mg/m{\ell}$ Bovine SIgA showed a marked bacteriostatic effect increased by increasing the concentration. Bovine IgG had not show bacteriostatic effect against both enterotoxigenic type Salmonella. Egg lysozyme as well as bovine SIgA also showed a marked bacteriostatic effect increased by increasing the concentration. 3. When the growth inhibition of human SIgA was tested by adding egg lysozyme with time interval, egg lysozyme showed bacteriostatic effect as compared with control. But human SIgA and adding with lysozyme showed slight the bacteriostatic effect. 4. When the growth inhibition of bovine SIgA was tested by adding egg lysozyme with time interval, all treatment against S. enteritidis showed bacteriostatic effect as compared with control In the case of S. typhinwrium, egg lysozyme showed a marked bacteriostatic effect as compared with control.

• 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.

• The Korean Journal of Pesticide Science
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• v.8 no.2
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• pp.137-144
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• 2004

[ $\beta$ ]-Ketoacetoanilide chloride derivatives containing a substituent at 4 in phenyl group (para) reduced specifically the development of tomato late blight caused by Phytophthora infestans. Among $\beta$ketoacetoanilide chloride derivatives, five (KIST163, KIST170, KIST260, KIST263, and KIST267) were selected and tested for their protective, curative, systemic, persistent activities, and disease control efficacy against tomato late blight on adult plants. They exhibited a strong l-day protective activity and $EC_{50}$ of KIST163 and KIST170 were 21.9 and $14.5{\mu}g/mL$, respectively. However, they had little curative and systemic activities. Good persistence of KIST163 and KIST170 on tomato plants were observed against P. infestans; both KIST163 and KIST170 at $100{\mu}g/mL$ showed control values more than 75% in a 7-day protective applications. In addition, the two chemicals effectively controlled the occurrence of P. infestans on adult tomato plants. These results indicate that five $\beta$-ketoacetoanilide chloride derivatives are foliar fungicides with a preventive action and KIST163 and KIST170 have a potential for the control of tomato late blight in the fields.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.5
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• pp.496-501
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• 1992

The present work tested the inhibitory effects of bile acids on the cholesterol biosynthesis and the activity of HMG-CoA reductase in cultured rat hepatocytes. The uptake of bile acids in hepatocytes were increased in according to the different bile acid concentrations and culture times. The rate of cholesterol synthesis in cells were inversely decreased to the bile acid concentrations and culture times. As expected, insulin injection (4 units/100g body weight) showed an enhancing effect of the cholesterol synthesis and the HMG-CoA reductase activity. The addition of bile acids in medium of insulin-treated hepatocytes also showed the suppressing effect. This effect was directly confirmed in isolated hepatic icrosomes by the test of HMG-CoA reductase activity. In the test of $Na^+$,$K^+$-ATPase activity in the isolated hepatocyte membrane, only the cholic acid did not stimulate the enzyme system. The reason of such difference is not obvious, but this result indicates that the cholic acid could be absorbed by simple diffusion.

• Korean Journal of Plant Resources
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• v.25 no.4
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• pp.363-371
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• 2012

Sambucus williamsii var. coreana have been used as a traditional medical food. This research was conducted to investigate the antioxidants of S. williamsii var. coreana leave and stem extracts. Total phenolic content of S. williamsii var. coreana leaves and stem water extracts were 6.6 and 2.0 mg/mL. The EDA by DPPH free radical scavenging test of S. williamsii var. coreana leaves extracts were 99.5 and 89.7% in water and ethanol extracts contained phenolic 200 ${\mu}g/mL$. The stem extracts were 92.2 and 94.3% in water and ethanol extracts contained phenolic 200 ${\mu}g/mL$. The ABTS radical decolorization activity of water and ethanol extracts from leaves were 79.8 and 99.1% at phenolic 200 ${\mu}g/mL$ and water and ethanol extracts from stem were 90.8 and 97.2% at phenolic 200 ${\mu}g/mL$. The antioxidant protection factor of water and ethanol extracts from leaves were 1.1 PF and 1.1 PF at phenolic 200 ${\mu}g/mL$ and water and ethanol extracts from stem were 1.4 PF and 1.0 PF at phenolic 200 ${\mu}g/mL$. The TBARs of water and ethanol extracts from leaves were 88.7 and 98.1% at phenolic 200 ${\mu}g/mL$ and water and ethanol extracts from stem were 93.6 and 90.6% at phenolic 200 ${\mu}g/mL$. The antioxidative activities of extracts from S. williamsii var. coreana leaves and stem were higher than BHT as positive control. These results suggests that S. williamsii var. coreana extracts have the greatest property as a natural antioxidative source.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.3
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• pp.203-208
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• 2007

To develop a new whitening agent for cosmetics from natural products, Pimpinella brachcarpa was selected for its inhibitory effect on melanogenesis in B16 melanoma cells. Crude ethanolic extract of P. brachycarpa and its four fractions-hexane, ethyl acetate(EtOAc), butanol and aqueous were evaluated for antioxidative effects and tyrosinase inhibitory activity. To elucidate the mechanism of active compounds of P. brachycarpa, we investigated the changes in protein level of tyrosinase, TRP-1 and TRP-2 using Western blotting and the changes in mRNA level of tyrosinase using RT-PCR technique. Following UV irradiation, expression of ET-1 in HaCaT keratinocytes was measured by quantitative enzyme immunoassay(EIA) using human ET-1 antibody. Crude ethanolic extract of P. brachycarpa and its four fractions-hexane, EtOAc, butanol and aqueous had free radical scavenging effect by 87.2, 2.5, 97.2, 80.5, 49.8% at 100 ${\mu}g/mL$ and tyrosinase inhibitory effect by 18.3, 15.1, 55.4, 13.1, 0 % at 100 ${\mu}g/mL$. P. brachycarpa EtOAc fraction significantly inhibited melanin production in B16 melanoma cells. Treatment with P. brachycarpa extract for 72 h suppressed the biosynthesis of melanin up to 58 % at 100 ${\mu}g/mL$. Especially, the EtOAc fraction of P. brachycarpa reduced the tyrosinase activity and tyrosinase expression in B16 melanoma cells in a dose-dependent manner. mRNA levels of tyrosinase and TRP-1 were markedly reduced by the EtOAc fraction of P. brachycarpa. Moreover, at the concentrations of $12.5{\sim}50{\mu}g/mL$ of the fraction, the production of UV-induced ET-1 in HaCaT keratinocytes(24 h after 8 $mJ/cm^2$ UVB irradiation) was reduced about 40%(p<0.05). P. brachycarpa could be used as a new natural skin-whitening agent due to the inhibitory effect of on melanin biosynthesis and endothelin-1 expression.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.375-381
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• 2017

A full-scale field test was conducted to investigate the arching effect of an embankment pile. The arching effect calculated from the test results was compared with theoretical values. Measurements obtained from a load cell and an earth pressure cell during the field test reflected the arching effect of the embankment pile well. The arching effect measured by load cells for an embankment height of 3m or less was smaller than the theoretical value with the assumption of plain strain.The measured effect for a height of 4 m or more was larger than the theoretical value. In contrast to the consistent decrease of the theoretical arching effect, the arching effect obtained from the field test shows continually increasing trends. The arching effects calculated from the earth pressure cells were greater than those from the theory under the plain strain assumption, but the trend was similar to the theoretical one. The arching effects measured by the earth pressure cells an embankment heights of 2, 3, 4, 5, and 6 m were 1.05, 1.23, 1.29, 1.28, and 1.29 times greater than those from the theory under the assumption of plain strain. The arching effects from the field test were much greater than those from the theory under the installation of a pile grid.

• The Journal of the Korea Contents Association
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• v.21 no.11
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• pp.518-527
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• 2021

This study verifies the polyphenol and flavonoid contents of a dried extract, as well as its antioxidant effect and growth inhibitory effect on cancer cells to investigate the potential of yellow cherry tomatoes as a physiologically active food material. The polyphenol and flavonoid contents were determined as 10.96 ± 1.57 and 4.12 ± 0.41 mg/g, respectively. The antioxidant activity was confirmed by measuring DPPH and ABTS radical scavenging ability, and RC50-the concentration that reduces free radicals by 50%-were determined as 490.83 ± 17.35 ㎍/mL and 355.90 ± 0.79 ㎍/mL, respectively. The dried extract showed no cytotoxicity with respect to normal hepatocytes (Chang) and no growth inhibitory activity with respect to A549 lung cancer cells, whereas dried extract showed growth inhibitory activities of 15.2% and 18.4% with respect to human cervical adenocarcinoma (HeLa) and human hepatocellular carcinoma (HepG2) cells, respectively, when treated with a concentration at 100㎍/mL. The results of this study confirm the potential of yellow cherry tomatoes as a physiologically active food material by verifying their antioxidant activity and their growth inhibitory activity with respect to cervical and liver cancer cells.

• The Korean Journal of Pharmacology
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• v.32 no.3
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• pp.301-309
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• 1996

Since it has been reported that the depolarization-induced NE release is inhibited by activation of presynaptic $A_1-adenosine$ heteroreceptor in hippocampus, a large body of experimental data on the post-receptor mechanism of this process has been accumulated. But, the post-receptor mechanism of presynaptic $A_1-adenosine$ receptor on the NE release has not been clearly elucidated yet. Therefore, it was attempted to clarify the participation of $K^+-channel$ in the post-receptor mechanisms of the $A_1-adenosine$ receptor-mediated control of NE release in this study. Slices from rat hippocampus were equilibrated with $^3H-norepinephrine$ and the release of the labelled products was evoked by electrical stimulation (3 Hz, 5 $VCm^{-1}$, 2 ms, rectangular pulses), and the influence of various agents on the evoked tritium-outflow was investigated. Adenosine, in concentrations ranging from $1{\sim}30\;{\mu}M$, decreased the NE release in a dose-dependent manner, without affecting the basal rate of release. 4AP $(1{\sim}30{\mu}M)$, a specific A-type $K^+-channel$ blocker, increased the evoked NE release in a dose-related fashion, and the basal rate of release is increased by 10 and $30{\mu}M$. TEA $(1{\sim}10{\mu}\;M)$, a nonspecific $K^+-channel$ blocker, increased the evoked NE release in a dose-dependent manner without affecting basal release. The adenosine effects were significantly inhibites by 3 ${\mu}M$ 4AP and 10 mM TEA treatment. 4AP $(30{\mu}M)-$ and TEA (10 mM)-induced increments of evoked NE release were completely abolished in $Ca^{++} free, but these were recoverd in low $Ca^{++} medium. And the effects of $K^+-channel$ blockers in low $Ca^{++} medium were inhibites and abolishes by $Mg^{++} (4 mM) adding and TTX $(0.3{\mu}M)$ adding medium, respectively. These results suggest that the decrement of the evoked NE-release by $A_1-adenosine$ receptor is mediated by 4AP and TEA sensitive $K^+-channel$.