• Journal of Microbiology and Biotechnology
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• 제31권7호
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• pp.1022-1027
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• 2021

Three compounds were isolated from marine-derived Streptomyces sp. CNQ-031, and their inhibitory activities against monoamine oxidases (MAOs), acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-secretase (BACE-1) were evaluated. Compound 1 (5,7-dihydroxy-2-isopropyl-4H-chromen-4-one) was a potent and selective inhibitor of MAO-A, with a 50% inhibitory concentration (IC₅₀) of 2.70 µM and a selectivity index (SI) of 10.0 versus MAO-B. Compound 2 [5,7-dihydroxy-2-(1-methylpropyl)-4H-chromen-4-one] was a potent and low-selective inhibitor of MAO-B, with an IC₅₀ of 3.42 µM and an SI value of 2.02 versus MAO-A. Compound 3 (1-methoxyphenazine) did not inhibit MAO-A or MAO-B. All three compounds showed little inhibitory activity against AChE, BChE, and BACE-1. The K_i value of compound 1 for MAO-A was 0.94 ± 0.28 µM, and the K_i values of compound 2 for MAO-A and MAO-B were 3.57 ± 0.60 and 1.89 ± 0.014 µM, respectively, with competitive inhibition. The 1-methylpropyl group in compound 2 increased the MAO-B inhibitory activity compared with the isopropyl group in compound 1. Inhibition of MAO-A and MAO-B by compounds 1 and 2 was recovered by dialysis experiments. These results suggest that compounds 1 and 2 are reversible, competitive inhibitors of MAOs and can be considered potential therapies for neurological disorders such as depression and Alzheimer's disease.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1571-1576
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• 2012

A diarylurea compound 1 possessing pyrrolo[3,2-$c$]pyridine nucleus was designed and synthesized with structure similarity to Sorafenib. Compound 1 was tested over 60-cancer cell line panel at a single dose concentration of 10 ${\mu}M$ and showed high activity. It was further tested in a five-dose mode to determine its $IC_{50}$, TGI, and $LC_{50}$ values over the 60 cell lines. Compound 1 showed high potency and good efficacy, and was accordingly tested at a single dose concentration of 10 ${\mu}M$ over a panel of 40 kinases. At this concentration, it completely inhibited the enzymatic activities of a number of oncogenic kinases, including ABL, ALK, c-RAF, FLT3, KDR, and TrkB. The target compound was subsequently tested over these 6 kinases in 10-dose testing mode in order to determine its $IC_{50}$ values.

• 대한기계학회논문집A
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• 제22권1호
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• pp.142-147
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• 1998

Rotary bending fatigue tests were carried out on the nitrided titanium in order to investigate the effect of nitriding layer on fatigue limit. Main results obtained are as follows. (1) The fatigue limit of nitrided pure titanium is remarkably reduced because of enlargement of grain size at high heat treating temperature and high stress field created from the elastic interaction in the compound layer. (2) Further test using specimen which was removed nitrified layer gradually, were also conducted and it was found that by removing the compound layer the fatigue limit recovered as the level of basic material and rather increased by coming of a diffusion layer. Therefore it is concluded that the surface compound layer generated by nitriding treatment reduced the fatigue limit but diffusion layer increased it.

• 한국염색가공학회지
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• 제16권6호
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• pp.23-29
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• 2004

The purpose of this study is to improve the dyeability and the color fastness to light of cotton fabric dyed with extraction of cinnamon cassia. Cotton fabric was pretreated with chito-colla to enhance the dyeability, and K/S values were compared chito-colla pretreated fabric and untreated fabric. In addition, to improve of color fastness to light of dyed fabric, it was used FFC compound as mordant. Also, it was measured SOD-liked activity of FFC compound and lifht fastness of dyed fabrics. The results are as follow; K/S value of cotton fabric pretreated with chito-colla(5%) was much more increased than untreated fabric. SOD-liked activity of FFC compound was observed over 70%. Light fastness of cotton fabric treated with FFC compound was 3～4 grades.

• 대한의용생체공학회:의공학회지
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• 제13권1호
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• pp.47-54
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• 1992

We studied the characteristics of the compound electrode and found that the compound electrode provides the four-electrode method in a compact form. We developed a new method of measuring the skin impedance using simple electrodes at low frequencies. At high frequencies where the effect of internal tissue impedance is not negligible, we used the compensation method using compound electrodes since they measure the voltage right under the skin. At 50 kHz, we measured the real part of the skin impedance of less than $80{\Omega}$ on the thorax. We propose a simple instrument which can measure accurate skin impedance at various frequencies.

• International Journal of Oral Biology
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• 제44권4호
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• pp.165-172
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• 2019

Berberine has been used clinically for more than a decade to treat various diseases, has been shown to be effective in osteoblast differentiation, and is a potential treatment option for osteoporosis. However, compared with existing osteoporosis drugs, berberine is somewhat less effective. This study aimed to identify a new compound with efficacy superior to that of berberine. The osteogenic activities of various berberine derivatives were evaluated via cell differentiation in C2C12 preosteoblast cell lines. Alkaline phosphatase (ALP) staining assay and structure-activity relationship demonstrated that compound 2b had a potent osteogenic effect. Furthermore, compound 2b dose dependently increased ALP activity and showed no toxicity at the effective concentration, indicating its efficacy. Additionally, compound 2b upregulated BMP2-induced transcriptional activity in a promoter activity assay using ALP, BSP, and OC promoters.

• Bulletin of the Korean Chemical Society
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• 제35권3호
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• pp.919-924
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• 2014

Ambient ionization can be achieved by generating an electrospray directly from plant tissue ("leaf spray"). The resulting mass spectra are characteristic of ionizable phytochemicals in the plant material. By subtracting the leaf spray spectra recorded from the petals of two hibiscus species H. moscheutos and H. syriacus one gains rapid access to the metabolites that differ most in the two petals. One such compound was identified as the sambubioside of quercitin (or delphinidin) while others are known flavones. Major interest centered on a $C_{19}H_{29}NO_5$ compound that occurs only in the large H. moscheutos bloom. Attempts were made to characterize this compound by mass spectrometry alone as a test of such an approach. This showed that the compound is an alkaloid, assigned to the polyhydroxylated pyrrolidine class, and bound via a $C_3$ hydrocarbon unit to a monoterpene.

• 생약학회지
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• 제51권1호
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• pp.30-35
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• 2020

We previously reported that caffeic acid isolated from Lonicera japonica showed potent neuroprotective activities against glutamate injured neuronal cell death in primary cortical cells. In this study, we tried to confirm the neuroprotective activity in glutamate injured HT22 cells and elucidate mechanisms of neuroprotective action of caffeic acid. We used glutamate induced HT22 cell death as a bioassay system. The compound decreased reactive oxygen species increased by high concentration of glutamate treatment in HT22 cells. Also, Ca²⁺ concentration was decreased by this compound. This compound made mitochondrial membrane potential maintain to normal condition. This also affected anti-oxidative enzymes and glutathione contents. Treatment of this compound increased not only glutathione reductase and peroxidase to the control level and also amount of glutathione, an endogeneous antioxidant. These experimental results showed that caffeic acid isolated from L. japonica exerted potent neuroprotective activity through the anti-oxidative pathway.

• 동아시아식생활학회지
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• 제3권2호
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• pp.129-137
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• 1993

This study was attempted to determine the effect of reduction of phytate and phenol compound on the functional properties of sesame protein concentrate. The concentrates were prepared by using dist-water, HCI and butanol. The content of phytate and phenol compound in defatted sesame meal were 4.55% and 3.42% respectively. Considerable amount of phytate was reduced by using HCI, and butanol was effective in removing phenol compounds, Higher bulk density and fat absorption were found in sesame protein concentrate prepared by butanol but higher water absorption was found in the concentrate prepared by dist-water. Also, emulsifying and foaming properties were improved by butanol treatment.

• 열처리공학회지
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• 제16권2호
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• pp.71-77
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• 2003

We investigate the phase formation in the compound layer of cast irons during the gaseous nitrocarburising of four different cast irons, that contain different types of graphites in the shape and size. We examine the change in the surface roughness with the nitrocarburising time. The observation of cross-sectional microstructure and X-ray diffraction analysis indicate that the compound layer consists of single ${\varepsilon}-Fe_{2-3}(N,C)$ phase and that its thickness increases in a parabolic manner with the treatment time. The surface roughness parameters, Rz and Ra increase with increasing treatment time. In other words, the roughness parameters increase as the thickness of compound layer increases. The parameters also depend on the shape and size of graphite in the individual cast irons.