• The Plant Pathology Journal
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• v.29 no.1
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• pp.52-58
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• 2013

Fusarium head blight (FHB) caused by the filamentous fungus Fusarium graminearum is one of the most severe diseases threatening the production of small grains. Infected grains are often contaminated with mycotoxins such as zearalenone and trichothecences. During survey of contamination by FHB in rice grains, we found a bacterial isolate, designated as BN1, antagonistic to F. graminearum. The strain BN1 had branching vegetative hyphae and spores, and its aerial hyphae often had long, straight filaments bearing spores. The 16S rRNA gene of BN1 had 100% sequence identity with those found in several Streptomyces species. Phylogenetic analysis of ITS regions showed that BN1 grouped with S. sampsonii with 77% bootstrap value, suggesting that BN1 was not a known Streptomyces species. In addition, the efficacy of the BN1 strain against F. graminearum strains was tested both in vitro and in vivo. Wheat seedling length was significantly decreased by F. graminearum infection. However, this effect was mitigated when wheat seeds were treated with BN1 spore suspension prior to F. graminearum infection. BN1 also significantly decreased FHB severity when it was sprayed onto wheat heads, whereas BN1 was not effective when wheat heads were point inoculated. These results suggest that spraying of BN1 spores onto wheat heads during the wheat flowering season can be efficient for plant protection. Mechanistic studies on the antagonistic effect of BN1 against F. graminearum remain to be analyzed.

• Radiation Oncology Journal
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• v.5 no.2
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• pp.75-82
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• 1987

For evaluation of biological effect of $p^+(50.5MeV)$ Be neutron beam produced by Korea Cancer Center Hospital (KCCH) cyclotron the RBE had been measured in experimental tumor Walker 256 carcinosarcoma as well as normal tissue, mouse intestine and bone marrow, in single and fractionated irradiation. As pilot study, the RBE had been measured for the mouse jejunal crypt cells in single whole body irradiation of which the result was 2.8. The obtained RBE values of TCD 50 of Walker 256 tumor, bone marrow and intestine En single irraiation were 1.9, 1.9 and 1.5 respectively. In fractionated irradiation, the RBE value of tumor Walker 256 was decreased as increasing of fraction number and increased as increaing of fraction size.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.128-128
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• 1998

Matrix metalloproteinases (MMPs) are a family of zinc-dependent proteases that degrade extracellular matrix and basement membrane. These enzymes are play important roles in tumor cell invasion and metastasis, as well as angiogenesis and other connective tissue diseases. In our screening program for inhibitors of MMP-2 from fungal metabolites, we have isolated novel non-peptidic inhibitors of MMPs, designated gelastatin A and B from the culture broth of Westerdykella multispora F50733. The structures of gelastatin A and B were determined to be 3-(5E-hexa-2E,4E-dienylidene-2-oxo-5,6-dihydro-2H-pyran-3yl)-propanoic acid and 3-(5Z-hexa-2E,4E-dienylidene-2-oxo-5,6-dihydro-2H-pyran-3yl)-propanoic acid, respectively. Gelastatin A and B exist as a mixture of two stereoisomers in a ratio of 2: 1. The 2: 1 mixture of gelastatin A and B inhibited activated MMP-2 and MMP-9 with an IC$\sub$50/ value of 0.63, 5.29 ${\mu}$M, respectively. They inhibited the invasion of B16F10 melanoma cells through basement membrane Matrigel with dose dependent.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.154-155
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• 1998

Taurine, 2-aminoethanesulfonic acid is widely distributed in animal tissues and has a variety of biological activities. A recent worldwide study demonstrated beneficial effects of taurine on aging and age-associated disorders. In general, taurine levels in the brain decrease when an animal is subjected to pathologic conditions such as ischemia-anoxia and seizure. But taurine levels tend to increase in the brain in hypertention. In the present study, the blood-brain barrier BBB) transport of [$^3$H]taurine was compared between spontaneously hypertensive rats (SHR) and normotensive Sprague-Dawley rats (SD) using Internal artery carotid perfusion (ICAP) at a rate of 4$m\ell$/min for 10, 15 and 30 second. Calculated V$\_$D/, volume of distribution in brain, and PS, the permeability surface area product of [$^3$H]taurine through the BBB in SHR was a little lower than that in SD. PS for 15s is more higher than that of other seconds in both of them. It could be followed by taurine efflux back into blood after 15s. We also obtained pharmacokinetic parameters using intravenous injection of plasma volume marker, [$\^$14/C]sucrose and [$^3$H] taurine. PS value of [$^3$H]taurine in SHR (16.1 ${\pm}$ 2.9 ${\times}$ 10$\^$-3/ $m\ell$/min/g) was significantly higher than that in SD (7.4 ${\pm}$ 0.8 ${\times}$ 10$\^$-3/ $m\ell$/min/g). There is also significant difference for %ID/g in brain between SHR (0.195 ${\pm}$ 0.031) and SD (0.058 ${\pm}$ 0.003).

• Biomolecules & Therapeutics
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• v.22 no.3
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• pp.176-183
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• 2014

Cognitive impairment is a result of dementia of diverse causes, such as cholinergic dysfunction and Alzheimer's disease (AD). Houttuynia cordata Thunb. (Saururaceae) has long been used as a traditional herbal medicine. It has biological activities including protective effects against amyloid beta ($A{\beta}$) toxicity, via regulation of calcium homeostasis, in rat hippocampal cells. To extend previous reports, we investigated the effects of water extracts of H. cordata herb (HCW) on tauopathies, also involving calcium influx. We then confirmed the effects of HCW in improving memory impairment and neuronal damage in mice with Ab-induced neurotoxicity. We also investigated the effects of HCW against scopolamine-induced cholinergic dysfunction in mice. In primary neuronal cells, HCW inhibited the phosphorylation of tau by regulating p25/p35 expression in $A{\beta}$-induced neurotoxicity. In mice with $A{\beta}$-induced neurotoxicity, HCW improved cognitive impairment, as assessed with behavioral tasks, such as novel object recognition, Y-maze, and passive avoidance tasks. HCW also inhibited the degeneration of neurons in the CA3 region of the hippocampus in Ab-induced neurotoxicity. Moreover, HCW, which had an $IC_{50}$ value of $79.7{\mu}g/ml$ for acetylcholinesterase inhibition, ameliorated scopolamine-induced cognitive impairment significantly in Y-maze and passive avoidance tasks. These results indicate that HCW improved cognitive impairment, due to cholinergic dysfunction, with inhibitory effects against tauopathies and cholinergic antagonists, suggesting that HCW may be an interesting candidate to investigate for the treatment of AD.

• Membrane Journal
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• v.27 no.2
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• pp.138-146
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• 2017

The new types of phenoxy-carboxylatophenoxy cosubstituted polyphosphazene were synthesized with various substitution rates. Diabetic diagnostic membranes were prepapared with these types of polyphosphazenes and final absorbances at 680 nm through these membranes were measured at various concentrations of glucose in blood. Basically, the end-point results of varying absorbance values according to time (K/S) had a linear relationship to the glucose concentration. The effects of substitution rates with hydrophilic carboxylatophenoxy groups and hydrophobic phenoxy groups on the glucose concentration measurements were examined. It was very difficult to measure glucose concentration in less than 10% of the hydrophilic substitution rates, because the glucose penetration rate was too slow. But dose-response slope (DRS) values between glucose concentration and K/S values increased as the hydrophilic substitution rates increased in more than 10% of the hydrophilic substitution rates. However, in more than 30% of the hydrophilic substitution rates, DRS value was too rapidly increased, because glucose penetration rate was too fast.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.4
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• pp.498-503
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• 2015

This study was conducted to evaluate the cytotoxicity and ${\alpha}-Amylase$, ${\alpha}-Glucosidase$, pancreatic lipase inhibition in vitro by different solvent fractions from the roots of Codonopsis lanceolata. The values of $IC_{50}$ against Calu-6 cell showed a high effect in n-hexane fraction ($10.13{\mu}g/mL$) whereas DW fraction exhibited the weakest inhibition on cell viability, having an $IC_{50}$ value of over $1,000{\mu}g/mL$. The values of $IC_{50}$ against HCT-116 cell showed the highest activity in n-BuOH fraction ($102.01{\mu}g/mL$), followed by n-hexane fraction ($145.85{\mu}g/mL$), methylene chloride fraction ($332.02{\mu}g/mL$), ethyl acetate fraction ($462.93{\mu}g/mL$) and DW fracion ($>1,000{\mu}g/mL$). ${\alpha}-Amylase$ inhibitory activity in methylene chloride fraction and ethyl acetate fraction was found to have a higher inhibitory effect with 24.5% and 25.6% than the other fractions. The highest ${\alpha}-Glucosidase$ inhibitory activity was observed from the ethyl acetate fraction extract, while the extract of DW fraction showed the lowest level of inhibitory activity at given experiment concentration. The pancreatic lipase inhibitory activity of C. lanceolata was found to have a higher the effect in ethyl acetate fraction. Inhibition of lipase activity of the ethyl acetate fraction and n-hexane fraction showed a relatively high, while the extract of DW fraction showed the lowest level at given experiment concentration. These results suggested that the roots of C. lanceolata may assist in the potential biological activity on carbohydrate, lipid Inhibitory activity and anticancer activity.

• Korean Journal of Environmental Biology
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• v.24 no.1 s.61
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• pp.60-66
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• 2006

This study was carried out to obtain the biological fundamental data for the resources annexation of Crassostrea ariakensis in terms of the effect of temperature and salinity on growth. Water temperature during the sampling period was $3.5\sim26.2^{\circ}C$ and there was a little difference between each sites. Salinity was ranged from 2.6 to 29.5 psu, its maximum in Baealdo and its minimum in Dontak. The fatness index was the higher in Dontak than the other sites. In August, the value was the lowest in 3 sites. Therefore Crassostrea ariakensis is likely to have spawning period June and July. Size values $(mean{\pm}S.D.)$ of shell height was $149.7{\pm}19.8\;mm$ (Baealdo), $148.6{\pm}21.3\;mm$ (Seomjin bridge) and $143.1{\pm}17.6\;mm$ (Dontak), respectively. Relative growth equations among SH, SL, SW, TW and MW of Crassostrea ariakensis were ranged from 0.024 to 0.0471.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.238-242
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• 2007

Square root models were developed for predicting the kinetics of growth of Listeria monocytogenes in sesame leaves as a function of temperature (4, 10, or $25^{\circ}C$). At these storage temperatures, the primary growth curves fit well ($R^2=0.898$ to 0.980) to a Gompertz equation to obtain lag time (LT) and specific growth rate (SGR). The square root models for natural logarithm transformations of the LT and SGR as a function of temperature were obtained by SAS's regression analysis. As storage temperature ($4-25^{\circ}C$) decreased, LT increased and SGR decreased, respectively. Square root models were identified as appropriate secondary models for LT and SGR on the basis of most statistical indices such as coefficient determination ($R^2=0.961$ for LT, 0.988 for SGR), mean square error (MSE=0.l97 for LT, 0.005 for SGR), and accuracy factor ($A_f=1.356$ for LT, 1.251 for SGR) although the model for LT was partially not appropriate as a secondary model due to the high value of bias factor ($B_f=1.572$). In general, our secondary model supported predictions of the effects of temperature on both LT and SGR for L. monocytogenes in sesame leaves.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.56-60
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• 2017

Mineralization is an important biological process for conversion of organic nitrogen (N) to inorganic N which can be used by plants directly. To investigate the effect of different manures on soil mineralization, the soil amended with cattle (CtM), goat (GM), chicken manure (ChM) and pig slurry (PS) were incubated under in vitro condition and ammonium N ($NH_4{^+}-N$), ammonification rate and ammonia emission were determined for eighty-four days. $NH_4{^+}-N$ was the highest in PS-amended soil for the whole experimental period. $NH_4{^+}-N$ in PS-amended soil was gradually decreased until day 84, whereas it was rapidly decreased for the first 14 days and then slightly increased until 84 days in ChM-, CtM- and GM-amended soil. The ammonification rate showed negative value for the first 14 days in all treatments. From day 14, ammonification rate started to increase in CtM- and ChM-amended soil, whereas it was maintained in GM- and PS-amended soil until day 84. The daily ammonia emission was the highest in PS-amended soil ($41mg\;kg^{-1}d^{-1}$), followed by CtM-, ChM-, and GM-amended soil at day 1. It was gradually decreased until day 84 in all treatments. The total $NH_3$ emission was the highest in PS-amended soil with $0.6mg\;kg^{-1}$ for 84 days, while less than $0.1mg\;kg^{-1}$ in three other plots. These results indicate that different manures showed different soil ammonification rate and $NH_3$ emission.