• Natural Product Sciences
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• v.5 no.2
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• pp.107-111
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• 1999

To investigate less toxic antiviral agents from Basidiomycetes, EA, the water soluble substance, was isolated from the carpophores of Elfvingia applanata (pers.) Karst. Anti-varicella zoster virus (Oka strain; anti-VZV/Oka) activity of EA was examined in MRC-5 cells by plaque reduction assay in vitro. And the combined antiviral effects of EA with nucleoside anti-VZV agents, acyclovir and vidarabine, were examined on the multiplication of VZV/Oka. EA exhibited a concentration-dependent reduction in the plaque formation of VZV/Oka with a 50% effective concentration $(EC_{50})$ of $464.14\;{\mu}g/ml$. The results of combination assay were evaluated by the combination index (CI) that was calculated by the multiple drug effect analysis. The combination of EA with acyclovir showed more potent synergism with CI values of $0.18{\sim}0.62$ for $50{\sim}90%$ effective levels than that of EA with vidarabine with CI values of $0.67{\sim}1.04$.

• Bulletin of the Korean Chemical Society
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• v.29 no.10
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• pp.1977-1982
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• 2008

Novel bicyclo[3.1.0]hexanyl purine nucleoside analogues were synthesized as potential antiherpetic agents via a bicyclo[3.1.0]hexanol (${\pm}$)-8, which was prepared using a highly efficient carbenoid cycloaddition reaction. A highly diastereoselective reduction of ketone and a Mitsunobu reaction for the condensation of glycosyl donor (${\pm}$)-12 with 6-chloropurine were employed.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.8-14
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• 2008

For nondestructive inspection of electron beam (EB) welding part in automotive power transmission assembly, a pulse-echo ultrasonic testing apparatus in water immersion has been applied using the ultrasonic waves with a frequency of 10MHz. However various problems have appeared during the ultrasonic inspection, which led to some significant mistakes in automatic quality evaluation of the welding parts. Experimental study showed that the state of water couplant medium containing some amount of contaminants, rusts and anti-corrosion agents had considerable influences on the reduction of ultrasonic amplitudes during wave propagation. The amplitude reduction depending on the coupling medium state could bring about some mis-diagnoses for defects in the welding parts. The results proposed that for a reliable inspection of defects in welds the state of water medium should be kept in about 15 volume fractions (vol.%) of anti-corrosion agents and in minimized contaminants.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.77-84
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• 1999

To search for less toxic antiherpetic agents, the inhibitory effects of natural naringenin on the plaque formation of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in Vero cells were examined by the plaque reduction assay in vitro. Naringenin inhibited plaque formations of HSV-l and HSV-2 in a dose dependent manner. It also exhibited more potent antiherpetic activity on HSV-l with selectivity index (SI) of 19.1 than on HSV-2 with SI of 5.7 The combined antiherpetic effects of naringenin with nucleoside antiherpetic agents, acyclovir and vidarabine, were examined on the multiplication of these two strains of herpesviruses in Vero cells by the combination assay. The results of combination assay were evaluated by the combination index (CI) that was calculated by the multiple drug effect analysis. The combinations of naringenin with acyclovir on HSV-l and HSV-2 showed more potent synergism with CI values of 0.28∼0.81 for 50%, 70%, 90% effective levels than those with vidarabine with CI values of 0.86-3.28.

• The Plant Pathology Journal
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• v.27 no.1
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• pp.78-84
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• 2011

Antagonistic rhizobacteria, more specifically fluorescent pseudomonads and certain species of Bacillus, are known as biocontrol agents of fungal root diseases of agronomic crops. In this study, 144 bacteria were isolated from cucumber rhizosphere and screened as potential biological control agents against Phytophthora drechsleri, the causal agent of cucumber root rot, in vitro condition. Non-volatile compounds of 23 isolates showed noticeable inhibition zone (> 30%) against P. drechsleri, whereas volatile compounds of 7 isolates could prevent more than 30% of the mycelial growth of the fungus. All promising isolates, except of Pseudomonas flourescens V69, promoted significantly plant growth under in vitro condition. P. flourescens CV69 and V11 exhibited the highest colonization on the root. Results of the greenhouse studies showed that a reduction in disease incidence by use of some strains, and particularly use of strains CV6 and V11 as a soil treatment, exhibited a reduction in disease incidence so that suppressed disease by 85.71 and 69.39% respectively. Pseudomonas flourescens CV6 significantly suppressed disease in comparison to Ridomil fungicide. The use of mixture bacterial strains in the soil inoculated by the fungus resulting in falling down the most of the plants which didn't show significant difference with infected control soils without bacteria.

• Journal of Life Science
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• v.24 no.1
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• pp.98-103
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• 2014

NAD(P)H quinone oxidoreductase 1 (NQO1) is a flavoprotein that catalyzes the two electron reduction of diverse substrates, including quinones. It uses NADH or NADPH as a cofactor for enzymatic machinery. In the metabolism of quinones, NQO1 has two conflicting functions because of the different stability of converted hydroquinones. The stable form of hydroquinone is excreted from cells by conjugation with glutathione or glucuronic acid. The unstable form of hydroquinone induces cell death by induction of oxidative stress and DNA damage. Certain quinones known as bio-reductive agents have a cytotoxic function following reduction by NQO1. Bio-reductive agents, such as ${\beta}$-lapachone or mitomycin C, induce the depletion of NAD(P)H and the generation of oxidative stress in an NQO1-dependent manner. NQO1 is highly expressed in several cancer tissues. Therefore, NQO1 is a good therapeutic target for cancer treatment with bio-reductive agents.

• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.925-934
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• 2010

Three typical biological solid wastes, namely, animal manure, garbage, and sewage sludge, were compared with regard to the composting process and the changes in microbial community structure. The effects of different bulking agents such as rice straw, vermiculite, sawdust, and waste paper were compared in manure compost. The differences in the microbial community were characterized by the quinone profile method. The highest mass reduction was found in garbage composting (56.8%), compared with manure and sludge (25% and 20.2%, respectively). A quinone content of $305.2\;{\mu}mol/kg$ was observed in the late stage of garbage composting, although the diversity index of the quinone profile was 9.7, lower than that in manure composting. The predominant quinone species was found to be MK-7, which corresponds to Gram-positive bacteria with a low G+C content, such as Bacillus. The predominance of MK-7 was especially found in the garbage and sludge composting process, and the increase in quinones with partially saturated long side-chains was shown in the late composting process of manure, which corresponded to the proliferation of Actinobacteria. The effects of different bulking agents on the composting process was much smaller than the effects of different raw materials. High organic matter content in the raw materials resulted in a higher microbial biomass and activity, which was connected to the high mass reduction rate.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.1993-1996
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• 2010

Silver nanoparticles has been prepared by the $\gamma$-irradiation and in situ reduction methods. Based on the Raman spectra, TEM images, X-ray Diffraction (XRD) patterns and UV-vis spectra, the in situ reduction method is more stable and the average size of the silver nanoparticles is also smaller than by the $\gamma$-irradiation reduction method. It is identified that the silver ions interacting with nonbonding electrons of oxygen atom in the carbonyl group of polyvinylpyrrolidone (PVP) by the in situ reduction method. It is also found advantages of the in situ reduction method including no additional reducing agents, without $\gamma$-irradiations treatment and the room temperature treatment suitability.

• Journal of the Korean Chemical Society
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• v.39 no.10
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• pp.812-817
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• 1995

Rapid and selective reduction of aromatic nitro compounds is of important for the preparation of amino derivertives in organic synthesis, particularly when a molecule has other reducible substituents. While Bakers' Yeast has been used for the enantioselective reduction of carbonyl compounds, little attention has been paid to the reduction of aromatic nitro compounds with Bakers' Yeast. Nitro group of m-bromonitrobenzene was selectively and rapidly reduced to corresponding amino derivative in good yield by Bakers' Yeast in basic solution. Furthermore, nitrosobenzene was rapidly reduced to aniline in good yield by Bakers' Yeast under neutral condition. In this paper, we wish to report a rapid and simple reduction of m-bromonitrobenzene and nitrosobenzene to the corresponding amino derivatives using Bakers' Yeast. And the effects of various agents, temperature and pH on the reduction will be discussed.

• Journal of Marine Bioscience and Biotechnology
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• v.12 no.1
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• pp.1-10
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• 2020

Asthma is a complex inflammatory disease of the lung characterized by variable airflow obstruction, airway hyperresponsiveness, airway inflammation, and reduction of respiratory function. Its prevalence and incidence are increasing because of the effect of various environmental and lifestyle risk factors. Steroid inhalation, long-acting agonists, and other synthetic drugs are used for the treatment of this disease. However, they have some side effects and show unsatisfied result and response after treatment. Therefore, many researchers have focused on the development of natural product-related treatment for asthma to suppress the side effects and unsatisfied results. Seaweeds contain various bioactive compounds with anti-inflammatory, antibacterial, and anti-oxidant activities. Thus, we investigated the asthma treatment-related literature using marine algae via the Google scholar search engine. Consequently, the literature is rarely investigated, but is increasing steadily. The literature was performed as a comparison study with an ovalbumin-induced group or drug-treated group, and investigated the antiasthma activity of algae ethanol extract. Although many researchers have studied marine algae-derived therapeutic agents for asthma, the amount of literature is rare compared with those of herbal medicine-derived therapeutic agents. Conclusively, we suggest that many researchers should investigate and develop algae-derived therapeutic agents for asthma treatment.