• Korean Journal of Pharmacognosy
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• v.34 no.1 s.132
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• pp.18-24
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• 2003

The repeated column chromatographic separation of the MeOH extract of Laportea bulbifera Weddell resulted in the isolation of five flavonoids. Structures of the isolated compounds have been identified as $isorhamnetin-7-O-{\alpha}-L-rhamnoside$ (1), $isorhamnetin-3-O-{\alpha}-L-rhamnoside$ (2), $isorhamnetin-3,7-O-{\alpha}-L-dirhamnoside$ (3), $isorhamnetin-3-O-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)-{\beta}-galactopyranoside$ (4), $isorhamnetin-3-O-{\alpha}-rhamosyl-(1{\rightarrow}2)-rhamnoside$ (5) by spectroscopic means.

• Archives of design research
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• v.20
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• pp.211-217
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• 1997

Natural dyes don't pollute the environments in contrast to artifical dyes. The cloths dyed with natural material can be developed into insect-proof clothing and bedding. With natural tint, they can also produce natural images. The purpose of this paper is to show the way to develop the natural dye material easily available at cheap cost, to produce high value added products in terms of dyeing a wide range of colors by using this material, and to suggest the way for farmers to cultivate the onions in their idle land, thus gaining additidnal income. In the process of dyeing natural cloth with onion skin produced largely in Mooan, Chonnam, we were able to extract a wide spectrum of colours from yellow to pale brown and gray. Having reaped good results in the various endurance tests(of washing, friction, water, sweat, sunlight), this material is estimated to be highly worthy of industrialization.

• Natural Product Sciences
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• v.19 no.3
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• pp.242-250
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• 2013

The autophagy-lysosomal pathway is an important protein degradation system, and its dysfunction has been implicated in a number of neurodegenerative diseases, including Parkinson's disease. Raphani Semen, one of the herbs of Yeoldahanso-tang (YH), has neuroprotective effects via the autophagy pathway. The activity-guided method was used to isolate and identify the components of Raphani Semen. In this experiment, the total extract of Raphani Semen was partitioned to n-butanol, methylene chloride, and water fractions. Flow cytometry data showed that only the water fraction showed autophagy-inducing activity in vitro. Compounds 1 and 2 were isolated from this water fraction by preparative HPLC separation. The structures of compounds 1 and 2 were identified as stachyose and raffinose, respectively, by the analysis of various spectral data ($^1H$ NMR, $^{13}C$ NMR, and MS) and comparisons with standard stachyose and raffinose. Of these two compounds, raffinose showed autophagy-inducing activity in PC12 cells through the mTOR pathway.

• BMB Reports
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• v.50 no.3
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• pp.111-116
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• 2017

Natural product drugs, or botanical drugs, are drugs composed of natural substances which have constituents with healthenhancing or medicinal activities. In Korea, government-led projects brought attention to botanical drugs invigorating domestic botanical drug industry. Foreign markets, as well, are growing bigger as the significance of botanical drugs stood out. To follow along with the tendency, Korea puts a lot of effort on developing botanical drugs suitable for global market. However, standards for approving drug sales vary by countries. And also, thorough standardization, certification, clinical studies and data of these will be required as well as data confirming safety and effectiveness. Meanwhile, as an international exchange in botanical drug market continues, the importance of plant resources was emphasized. Thus countries' ownership of domestic natural resources became vital. Not only establishing a systematic method to secure domestic plant resources, but also cooperation with other countries on sharing natural resources is essential to procure natural resources effectively. Korea started to show visible results with botanical drugs, and asthma/COPD treatment made out of speedwell is one example. Sufficient investment and government's active support for basic infrastructure for global botanical drugs will bring Korea to much higher level of botanical drug development.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.6
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• pp.607-613
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• 2009

A new formulation of NDIF method to the algebraic eigenvalue problem is introduced to efficiently extract natural frequencies of arbitrarily shaped plates with the simply supported boundary condition. NDIF method, which was developed by the authors for the free vibration analysis of arbitrarily shaped membranes and plates, has the feature that it yields highly accurate natural frequencies compared with other analytical methods or numerical methods(FEM and BEM). However, NDIF method has the weak point that it needs the inefficient procedure of searching natural frequencies by plotting the values of the determinant of a system matrix in the frequency range of interest. A new formulation of NDIF method developed in the paper doesn't require the above inefficient procedure and natural frequencies can be efficiently obtained by solving the typical algebraic eigenvalue problem. Finally, the validity of the proposed method is shown in several case studies, which indicate that natural frequencies by the proposed method are very accurate compared to other exact, analytical, or numerical methods.

• Korean Journal of Pharmacognosy
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• v.50 no.3
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• pp.155-158
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• 2019

Cornus alba (CA) geographically distributes in Korea, Japan, Northeast China and Russia. The cornus species have been used traditionally as anti-inflammatory, hemostatic and diuretic in Korea. Previously, it was reported CA and its separated components have excellent antioxidant, anti-inflammatory and anti-prostate cancer efficacy. Present work, the validation and content determination was tried on the ellagitannin, cornusiin B which were isolated from the CA by using high-performance liquid chromatography (HPLC). As a result, the content of cornusiin B were 3.07% in ethanolic extract of CA.

• Structural Monitoring and Maintenance
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• v.6 no.2
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• pp.85-101
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• 2019

The effects of foundation scour depth and riverbed condition on the natural frequencies of a typical cross-river integral abutment bridge have been studied. The conventional operational modal analysis technique has been employed in order to extract the modal properties of the bridge and the results have been used in the Finite Element (FE) model updating procedure. Two tests have been carried out in two different levels of water and wet condition of the riverbed. In the first test, the riverbed was in dry condition for two subsequent years and the level of water was 10 meter lower than the natural riverbed. In the second test, the river was opened to water flow from the upstream dam and the level of water was 2 meter higher than the natural riverbed. The results of these two tests have also been used in order to find to what extend the presence of water flow in the river and saturation of the surrounding soil affect the bridge natural frequencies. Finally, the updated FE model of the bridge has been applied in a series of parametric analyses incorporating the effect of piles' relative scour depth on the bridge natural frequency of the first four vibration modes.

• International Journal of Internet, Broadcasting and Communication
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• v.14 no.4
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• pp.189-197
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• 2022

Today, we are exposed to various text-based media such as newspapers, Internet articles, and SNS, and the amount of text data we encounter has increased exponentially due to the recent availability of Internet access using mobile devices such as smartphones. Collecting useful information from a lot of text information is called text analysis, and in order to extract information, it is performed using technologies such as Natural Language Processing (NLP) for processing natural language with the recent development of artificial intelligence. For this purpose, a morpheme analyzer based on everyday language has been disclosed and is being used. Pre-learning language models, which can acquire natural language knowledge through unsupervised learning based on large numbers of corpus, are a very common factor in natural language processing recently, but conventional morpheme analysts are limited in their use in specialized fields. In this paper, as a preliminary work to develop a natural language analysis language model specialized in the railway field, the procedure for construction a corpus specialized in the railway field is presented.

• Korean Journal of Weed Science
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• v.32 no.3
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• pp.211-221
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• 2012

The fourth leaves (younger leaves) amongst extended 4-upper leaves in 18 squash cultivar were the highest tolerance to the paraquat application, followed by third, the second, and the first leaves (older leaves). The forth leaves in Joongangaehobak showed more than three times higher tolerance to the paraquat application than did the first leaves. When the combining of water extract from the fourth leaves with paraquat were applied to the leaves and stems of maize, the paraquat phytotoxicity in maize was reduced compared to the paraquat application alone. Therefore, this study continued to investigate if the phytotoxicity inhibitor exist in the fourth leaves. The water extract in the fourth leaves were isolated by silica gel column chromatography, Sephadex LH-20 column chromatography, TLC, and HPLC, and the substance in the extract was speculated as a malic acid by identifying through NMR. The mixture malic acid and paraquat were applied to the maize to verify the application effect of malic acid on paraquat toxicity. The 100 ${\mu}M$ of paraquat application alone showed 62% of paraquat toxicity to the corn leaves, while the combined application of 100 ${\mu}M$ paraquat with malic acid at 0.1, 0.3, 0.5, and 1.0% did not show the symptom.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.105-111
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• 2010

Caesalpinia sappan L. has long been commonly used in oriental folk medicines to treat diseases. To investigate the antibacterial effects from C. sappan L. heart wood, the MeOH soluble extract was successively fractionated by using hexane, $CHC1_3$, EtOAc, BuOH, MeOH, and $H_2O$. Among of these extracts, the EtOAc fraction which partitioned to 3.94% of the highest yields was to be the most active against all human pathogenic bacteria in this experiment. In addition, the antibacterial activities of the EtOAc fraction were more effective against Gram (+) bacteria compared to those against Gram (-) bacteria, which showed difference of the antibacterial activities against Gram (-) bacteria. To confirm the identity of the active substances, the EtOAc fraction was further separated by silica gel adsorption column, high performance liquid chromatography, and 98.48% purity of brazilin (1.67 mg)/EtOAc (10 mg) fraction was obtained from 300 g of C. sappan L. heart wood. The isolated active substance was a single compound of yellow crystalline, and was identified as brazilin ($C_{16}H_{14}O_5$) by MS, and $^lH$-NMR and $^{13}C$-NMR. These results suggest that the brazilin in the EtOAc fraction from MeOH extract of C. sappan L. has a potential as a natural therapeutic agent against human pathogenic Gram (+) bacteria such as Staphylococcus aureus.