• YAKHAK HOEJI
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• v.40 no.6
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• pp.653-658
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• 1996

As part of our search for less toxic antimicrobial agents from natural resources. rutin was isolated from Sophora japonica and then hydrolyzed to quercetin. Antimicrobial activity of quercetin was tested in vitro against five kinds of gram positive and ten kinds of gram negative bacteria by serial broth dilution method. Among fifteen kinds of bacteria tested, the antimicrobial activity of quercetin was the most potent against Proteus vulgaris showing minimal inhibitory concentration(MIC) of 125 ${\mu}$g/ml. To investigate the effect of antimicrobial combinations of quercetin with four kinds of antibiotics (ampicillin, cefazolin, oxytetracycline and chloramphenicol). the fractional inhibitory concentration index (FICI) was determined by checkerboard assay for each strain. The antimicrobial combinations of quercetin with four kinds of antibiotics resulted in synergism in one instance, additive effect in four instances, but no antagonism was observed.

• Natural Product Sciences
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• v.14 no.1
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• pp.32-36
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• 2008

The antimicrobial activity of seventy five ethanol extracts obtained from 67 different kinds of plant species of the Mongolian flora were evaluated by means of the disc diffusion method against five species of microorganisms, Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, Micrococcus luteus and Pseudomonas aeruginosa. Among the plant extracts examined, 34 kinds of extracts demonstrated significant antibacterial activity against one or more species of microorganisms, respectively. Especially, the root extract of Paeonia anomala, the whole herb extract of Myricaria alopecuroides, the whole herb extract of comarum zalesovianum, the whole herb extract of Agrimonia pilosa and some other plant extracts demonstrated a particularly potent antimicrobial activity. The ethylacetate fractions obtained from the whole herb extract of Myricaria alopecuroides and from those of Sedum aizoon, Paeonia anomala, Sedum hybridum and Dasiphora fruticosa exhibited a particularly potent antibacterial activity especially against Staphylococcus aureus and Micrococcus luteus.

• Korean Journal of Pharmacognosy
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• v.28 no.4
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• pp.192-197
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• 1997

As a part of searching for new antitumor agents from natural products, 94 kinds of Chinese plants were extracted with petroleum ether/ether (1:1), ethyl acetate and methanol, successively and their cytotoxicities were evaluated against A549 (human lung carcinoma) cell line. Among them, six kinds of ether extracts, seven kinds of ethyl acetate extracts and one kind of methanol extracts showed significant cytotoxic activities (above 70% inhibition) at a concentration of $50\;{\mu}g/ml$. These results surest that they may be involved in natural sources with possible anticancer activities.

• Korean Journal of Pharmacognosy
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• v.29 no.4
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• pp.323-330
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• 1998

For the search of new antineoplastic agents from natural resources, two hudred and one kinds of oriental medicinal drugs were extracted with petroleum ether/ether(1:1), ethyl acetate and methyl alcohol, successively and their cytotoxicities were evaluated against A549 (human lung carcinoma) and SK-OV-3 (human ovary adenocarcinoma) cell lines. Among them, thirty kinds of ether extracts, forty-one kinds of ethyl acetate extracts and nine kinds of methanol extracts showed significant cytotoxic activities (above 70% inhibition) against A549 cell lines at a concentration of $40\;{\mu}g/ml$. And also, twenty-four kinds of ether extracts, thirty-one kinds of ethyl acetate extracts and six kinds of methanol extracts showed significant cytotoxic activities against SK-OV-3 cell lines at the same concentration.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.1
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• pp.19-26
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• 2003

In recent years, numerous studies have been carried out to find out the possible substitution of PE-coated paperboards used in packaging of watery or oily foods. Accordingly, this study was carried out to obtain the basic data for producing higher functional coating agents for pulp mold by evaluating various kinds of mixed coating agents. At that time, two kinds of synthetic coating agents(AKD, PYA) and three kinds of natural coating agent(CMC, corn starch, oxidized starch) were used for making the mixed coating agents respectively. Physical properties of coated paperboards were tested. Conclusions obtained from this study were as follows. Based on concentrations, the proper mixture ratios were 10:90(AKD:CMC), 10:90(AKD:corn starch), 10:90(AKD:oxidized starch), 40:60(PVA:CMC), 20:80(PVA:corn starch) and 20:80(PYA:oxidized starch). The mixed coating agent of PYA:corn starch(20:80) was the most efficient coating agent. Consequently, water and oil resistance were improved even with much addition of natural coating agents. We consider that they can be suitable for the packaging used in the storage of higher moisture vegetables and other food, and also can be suitable for oily fried food.

• Journal of KSNVE
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• v.8 no.5
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• pp.936-948
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• 1998

A theoretical formulation for the analysis of free vibration of a cylindrical shell with a circular plate attached at an arbitrary axial position of the shell under various kinds of boundary conditions was derived and programed to get the numerical results for natural frequencies and mode shapes of the combined system. The boundary conditions of the shell to be considered here are clamped-free, clamped-simply supported, both ends clamped and both ends simply supported. The frequencies and mode shapes from theoretical calculation were compared with those of commercial finite element code, ANSYS. The results showed good agreement with those of ANSYS in frequencies and mode shapes. The program will contribute to the design optimization of a shell/plate combined system through the analysis of natural frequencies and mode shapes for the system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.6
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• pp.1167-1174
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• 2006

Text region detection from a natural scene is useful in many applications such as vehicle license plate recognition. Therefore, in this paper, we propose a text region extraction method using pattern histogram of character-edge maps. We create 16 kinds of edge maps from the extracted edges and then, we create the 8 kinds of edge maps which compound 16 kinds of edge maps, and have a character feature. We extract a candidate of text regions using the 8 kinds of character-edge maps. The verification about candidate of text region used pattern histogram of character-edge maps and structural features of text region. Experimental results show that the proposed method extracts a text regions composed of complex background, various font sizes and font colors effectively.

• Korean Journal of Pharmacognosy
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• v.30 no.2
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• pp.105-110
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• 1999

In our continuing search for new antineoplastic agents from natural products, one hundred and thirty-five herbal drugs were extracted with petroleum ether/ether (1:1), ethyl acetate and methyl alcohol, successively and their cytotoxicities were evaluated against A549 (human lung carcinoma) and SK-OV-3(human ovary adenocarcinoma) cell lines. Among them, fifteen kinds of ether extracts, eighteen kinds of ethyl acetate extracts and seven kinds of methanol extracts showed significant cytotoxic activities (above 70% inhibition) against A549 cell lines at a concentration of $40\;{\mu}g/ml,$ while ten kinds of ether extracts, thirteen kinds of ethyl acetate extracts and six kinds of methanol extracts demonstrated significant cytotoxic activities against SK-OV-3 cell lines at the above same concentration.

• Korean Journal of Pharmacognosy
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• v.10 no.3
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• pp.108-111
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• 1979

In vivo antioxidant activities were screened over 30 kinds of crude drugs which are most frequently prescribed in oriental medicine. Of these, only Ginseng Radix, Cimicifugae Rhizoma, Zingiberis Rhizoma(steam dried), Alismatis Rhizoma, and Liriopes Tuber were shown to be positive in the activity.

• Natural Product Sciences
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• v.17 no.3
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• pp.165-174
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• 2011

Naturally occurring small molecules from plants, microorganisms, and animals allow the design of drugs that can be beneficial in virtually all kinds of human diseases. Liver diseases with diverse etiologies such as viral infection, chemical intoxication, and metabolic fat accumulation are one of the leading causes of human mortality. Unfortunately, however, there are few effective drugs available capable of stopping or reversing the progress of liver disease. Here, we discuss the current advances in developing hepatoprotective natural products for several arrays of liver disease pathogenesis.