• Proceedings of the PSK Conference
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• 2002.10a
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• pp.372.1-372.1
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• 2002

AIzelin (1) and quercitrin (2) isolated from the EtOAc-soluble fraction of the leaves of Litsea japonica Jussieu (Lauraceae) showed inhibitory activity against classical pathway complement system with 50% inhibitory concentration ($IC_{50}$/) values of 112.2 and 198.2 $\mu\textrm{g}$/$m\ell$. respectively. For the structure-activity relationship of flavonoids on anti-complement system. myricitrin (3) from JUQ/ans mandshurica Maximowicz (Juglandaceae) also tested anti-complement activity. while this was devoid of any significant activity. (omitted)

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.321-322
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• 1996

Using the data on the occurrences of the Ho: and soft X-ray flares for the time interval of January 1, 1986-May :31, 1994, we have studied the middle term(30-300days) pericities of the solar flare production during the activity cycle 22. Power analysis of the time seies of daily H$\alpha$ flare index in the northern hemisphere shows prominent periodicities at 220, 120, 109, and 92 days(see Figures l(a) and l(b)), while in the southern hemisphere, those at 267, 213, 183, 167, and 107 days are apparent, though their peaks are not so distint as those in the northern hemisphere. Periodogram of daily soft X-ray flare index also reveal the periodicities at 279, 205, 164, 117, and 91 days in the northern hemisphere, and at 266, 220, 199, 162, 120, and 100 days in the southern hemisphere. Howeer, the 155-day periodicity reported for the earlier cycles, 19, 20, and 21, could not be confirmed in our analysis. to be submitted to Solar Physics; an extended abstract.

• Journal of The Korean Astronomical Society
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• v.54 no.4
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• pp.121-128
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• 2021

It has been known that the global asteroseismic parameters as well as the stellar acoustic mode parameters vary with stellar magnetic activity. Some solar-like stars whose variations are thought to be induced by magnetic activity, however, show mode frequencies changing with different magnitude and phase unlike what is expected for the Sun. Therefore, it is of great importance to find out whether expected relations are consistently manifested regardless of the phase of the stellar magnetic cycle, in the sense that observations are apt to cover a part of a complete cycle of stellar magnetic activity unless observations span several decades. Here, we explore whether the observed relations of the global seismic parameters hold good regardless of the phase of the stellar magnetic cycle, even if observations only cover a part of the stellar magnetic cycle. For this purpose, by analyzing photometric Sun-as-a-star data from 1996 to 2019 covering solar cycles 23 and 24, we compare correlations of the global asteroseismic parameters and magnetic proxies for four separate intervals of the solar cycle: solar minima ±2 years, solar minima +4 years, solar maxima ±2 years, and solar maxima +4 years. We have found that the photometric magnetic activity proxy, S_ph, is an effective proxy for the solar magnetic activity regardless of the phase of the solar cycle. The amplitude of the mode envelope correlates negatively with the solar magnetic activity regardless of the phase of the solar cycle. However, relations between the central frequency of the envelope and the envelope width are vulnerable to the phase of the stellar magnetic cycle.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.308-314
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• 2012

This study was carried out to investigate the antibacterial activity against pathogens of acne and the anti-inflammatory effect of 75% ethanol extract and its fractions from the leaves of Prunus sargentii. In the antibacterial activity by the disc diffusion assay, the extract showed the highest effect against Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis in 5 mg/disc. However, the ethyl acetate fraction showed the highest antibacterial activity in 1 mg/disc. On the other hand, the hexane and chloroform fraction showed strong nitric oxide (NO) production inhibitory effect in lipopolysaccharide (LPS)-stimulated Raw 264.7 cell. In the cell viability of Raw 264.7 by MTT assay, the extract and all fractions were exhibited normal viabilities as nontoxic result. Consequently, the extract from the leaves of P. sargentii and its ethyl acetate fraction could be applicable to functional materials for antibacterial activity related fields. Moreover, the hexane and chloroform fraction could be applicable to candidate materials as anti-inflammatory agent.

• Korean Journal of Pharmacognosy
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• v.42 no.2
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• pp.169-174
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• 2011

In this study, we investigated on antioxidative activity, antibacterial activity and tyrosinase inhibitory activity in 75% ethanol extracts of bark and cork layer from Prunus sargentii. The total polyphenol content of cork and bark extract was found to be 217.4 mg/g and 184.3 mg/g. And flavonoid content was found to be 31.9 mg/g and 58.6 mg/g respectively. In DPPH radical scavenging ability, cork extract was exhibited stronger scavenging ability than bark extract. Moreover, cork extract was showed higher inhibitory activity than bark extract in tyrosinase inhibitory activity. In antibacterial activity, bark extract was showed higher growth inhibition effect than cork extract against tested bacterial strains. In measurement of cytotoxicity by MTT assay, bark and cork extract showed fine cell viabilities(95.7~120.9%) against RAW 264.7 cell.

• The Korean Journal of Mycology
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• v.9 no.2
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• pp.103-108
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• 1981

The antibiotic-producing Streptomyces strains were isolated from the soils of various localities in Yeang-Kwang and tested for the activity against some of gram positive and negative microorganisms, especially against Pseudomonas aeruginosa. The results are summarized as follows. 1. A total of 1464 Streptomyces strains were isolated from 336 soil samples. Of all the strains tested, 636 strains of the isolates showed antibiotic activity against either gram positive or negative test organisms. And 408 of the 636 strains were strongly active against one or all of those test­organisms. 2. Ninety-three of Streptomyces strains among the active isolates showed the antibiotic activity against Pseudomonas aeruginosa, and 24 of 93 strains showed the strong antibiotic activity against all of the test organisms i.e. Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Salmonella typhi and Shigella jlexneri. 3. Antibiotic-producing Streptomyces strains active against Pseudomonas aeruginosa were isolated from the soil samples taken from vegetable field, paddy field, sandy ground and roadway, but not isolated from the soil taken from dwelling area, grass field and piers.

• Korean journal of food and cookery science
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• v.31 no.5
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• pp.596-604
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• 2015

This study investigated changes in the chemical properties and antioxidant activity of dried shredded radish (Raphanus sativus L.). Shredded radishes with a thickness of either 3.5 mm or 7.0 mm were dried using hot air at $45^{\circ}C$ or were sun dried. The degree of browning for the 3.5 mm sun dried radish, the 7.0 mm sun dried radish, the 3.5 mm hot air dried radish and the 7.0 mm hot air dried radish was 0.12, 0.14, 0.04 and 0.04, respectively. The DPPH radical scavenging activity (EDA%) of the hot air dried radish had a higher value than the sun dried radish. In contrast, the ABTS values of the sun dried radishes were higher than the hot air dried radishes. The total polyphenol content of the 7.0 mm and 3.5 mm hot air dried radishes reached high values of 15.99 and 11.62 mg/g, respectively. The total polyphenol contents of the 7.0 mm and 3.5 mm sun dried radishes were 9.63 and 6.77 mg/g, respectively. In sensory evaluation of the stir-fry dried shredded radishes, the 7.0 mm hot air dried sample scored the highest in terms of smell, color, gloss and overall preference. In conclusion, hot air drying ($45^{\circ}C$) and a thickness of 7.0 mm were found to be the optimal conditions for dried shredded radish and stir-fried dried shredded radish products.

• BMB Reports
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• v.41 no.11
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• pp.765-770
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• 2008

Undesirable hyperpigmentation that can arise from increased melanocyte activity may be alleviated by targeting active melanocytes for apoptosis. The role of Stathmin 1 as an important regulator of microtubule dynamics is well documented. The current study examined the potential of Stathmin 1-targeting strategies in eliminating active melanocytes. A vector to overexpress Stathmin 1 and vectors to express three distinct small hairpin RNAs to knockdown Stathmin 1 expression in normal melanocytes were produced and in cell cultures acted accordingly. Both overexpression and knockdown of Stathmin 1 led to a marked increase in melanocyte apoptosis, as indicated by the accumulation of apoptotic cells and increased levels of cleaved caspase-3. Both up- and down-regulation of Stathmin 1 expression inhibited the activity of differentiated melanocytes, as indicated by decreases in both melanin production and tyrosinase activity. Taken together, these results indicate that hyperactive melanocytes can be inhibited by altering Stathmin 1 expression.

• Culinary science and hospitality research
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• v.22 no.6
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• pp.14-23
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• 2016

This purpose of this study is to examine the antioxidant and antimicrobial activities of Persicaria hydropiper L. extract in 70% ethanol and in water, a medicinal herb, as an effort to examine the potential of medicinal herbs for development of antioxidants and natural preservative substitutes. The total poly-phenol content in the 70% ethanol extract and in the water extract were 19.88 mg/g and 7.46 mg/g, respectively. The DPPH radical scavenging activity was 90.99% and 64.98% in the 70% ethanol extract and water extract, in which 70% ethanol extract showed a higher activity. The antioxidant effect of Persicaria hydropiper L. extract appears to be very good and due to its excellent growth inhibitory effect on food-poisoning-causing microorganisms in the food, it is thought to be utilized as a potential natural preservative substitute in many areas.

• Journal of Astronomy and Space Sciences
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• v.24 no.2
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• pp.91-98
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• 2007

The existence of the North-South asymmetry of the solar activity is widely accepted even though the phenomenon is not yet satisfactorily understood. We have studied the temporal variations in the North-South asymmetry of the sunspot area during the period from May in 1874 to April in 2007. The combined data have been examined for periodicity in the solar activity North-South asymmetry. We have found that (i) solar northern and southern hemispheres show an asymmetric behavior, in terms of a sunspot area, (ii) sunspot areas in northern and southern hemispheres show clearly the 11 year periodicity when they were analyzed separately, as they do when analyzed together, (iii) in addition to the general 11 year periodicity in both northern and southern hemisphere solar activities, there are also noticeable shorter periodicities other than the 11 year periodicity in the asymmetry in North-South activity. Finally, we conclude by pointing out the importance of studying the North-South asymmetry of the solar activity.