• Korean Journal of Medicinal Crop Science
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• v.16 no.3
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• pp.192-194
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• 2008

In our previous study, ethylacetate fraction of white ginseng (root of Panax ginseng C.A. Meyer) extract inhibited mushroom tyrosinase activity and melanin production in melanocytes. This study examined its effects on the expression of melanin biosynthesis-related enzymes to explore the depigmenting pathway. Moreover, depigmenting effect on animal skin was examined using UV-B induced hyperpigmented skin of brown guinea pigs. The ethylacetate fraction of the white ginseng extract exhibited depigmenting activity in the skin of brown guinea pig without visible edema. In addition, this fraction reduced tyrosinase expression in melanocytes. The results suggested that ethylacetate fraction of white ginseng extract might be used as skin depigmenting material by inhibition of tyrosinase activity and expression.

• Journal of Life Science
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• v.7 no.3
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• pp.180-185
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• 1997

Methylelaiophylin generated superoxide radicals in Bacillus subtilis and showed antibacterial activity against a broad range of gram positive bacteria. The inhibition of DNA synthesis was more sensitive than one of RNA synthesis. A recombination-deficient mutant strain of B. subtilis was 2-fold more sensitive than a wild strain, and this sensitivity was reduced in the presence of an antioxidant, dithiothreitol. Methylelaiophylin generated superoxide radicals in B. subtilis lysates, and this suggests that the antibacterial activity of methylelaiophylin is related to the generation of active oxygen species in the cells.

• Food Science of Animal Resources
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• v.32 no.4
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• pp.409-413
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• 2012

This study aimed to compare the probiotic characteristics of twelve strains of Lactobacillus acidophilus including cholesterol assimilation and conjugated linoleic acid (CLA) production. Cholesterol assimilation exhibited some variation among L. acidophilus strains, which could be classified into three groups based on their assimilation levels (p<0.05). The high cholesterol assimilation group exhibited a significantly higher tolerance to 0.3 and 0.5% bile acid than the low cholesterol assimilation group (p<0.05). Cholesterol assimilation showed positive correlation with 0.5% bile tolerance, and a negative correlation with acid tolerance (p<0.01). Glycocholate deconjugation activity showed no relationship with cholesterol assimilation, whereas taurocholate deconjugation activity was shown to have negative correlation with cholesterol assimilation (p<0.05). CLA production by L. acidophilus strains exhibited a wide variation, ranging from 2.69 to 5.04 mg/g fat. CLA production of L. acidophilus GP1B was the highest among the tested strains, but there was no evidence for differences in CLA production in strain specificity. Based on these results, the cholesterol assimilation of L. acidophilus strains may not be related to deconjugation activity, but may in-fact be attributed to their bile-tolerance.

• Horticultural Science & Technology
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• v.29 no.1
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• pp.61-67
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• 2011

Barley (Hordeum vulgare L.) sprouts are a vegetable commonly used as a functional food material due to its high vitamin C concentration and antioxidant activity. In this experiment, we measured the changes in the antioxidant activity of several barley cultivars as well as in the concentrations of related compounds such as ascorbate and glutathione upon treatment with UV-B or salicylic acid (SA). The six barely cultivars were grown in a plant growth chamber (25/$18^{\circ}C$, 14/10 h, 200 ${\mu}mol{\cdot}m^{-1}{\cdot}s^{-1}$, 70% relative humidity) for 10 days. All barely cultivars showed different 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging activities, which were increased by UV-B treatment and not by SA treatment. The changes in ascorbate concentrations were correlated with DPPH scavenging activity in both the treatments, suggesting that the antioxidant activity in barley sprouts was mainly dependent on ascorbate concentration. Furthermore, changes in ascorbate concentration showed similar tendencies to changes in free sugar concentration, especially glucose and sucrose, in both treatments. On the other hand, the concentrations of glutathione and cysteine highly increased by SA treatment, representing different tendencies compared to the DPPH scavenging activity and ascorbate concentration. 'Donghanchal' cultivar showed comparatively higher antioxidant activity, both constitutively and inducingly by UV-B treatment, with its higher concentrations of ascorbate and glutathione. These results suggest that barley sprouts could be used as a health-functional vegetable, contributing to the overall supply of antioxidant and sulfur-containing organic compounds.

• Korean Journal of Biological Psychiatry
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• v.14 no.2
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• pp.129-141
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• 2007

Objectives : Empathy has been conceptualized as the ability of emotional resonance and perspective-taking. Emotional awareness has been proposed as the basis of empathy. In this study we examined the relationship between empathy and mood awareness and their neural correlates in resting-state activity in normal controls and patients with schizophrenia. Methods : Empathy and mood awareness scale scores were compared between 29 patients with schizophrenia and 21 normal controls by voxel-based t-tests and voxel-based correlation analyses of resting-state $^{18}F$-FDG PET images. Results : Empathy and mood labeling scale scores were significantly decreased in schizophrenic patients. Mood monitoring was positively correlated with empathy score in normal controls, but not in schizophrenic patients. In normal controls, empathy was positively correlated with resting-state activities in the intraparietal sulcus and mood monitoring was positively correlated with the temporal pole, frontopolar cortex, inferior temporal gyrus, entorhinal cortex and the subgenual prefrontal cortex resting activities. The orbitofrontal cortex resting activity was positively correlated with mood monitoring-related subgenual prefrontal cortex activity in the normal controls. Patients with schizophrenia showed decreased orbitofrontal resting activity and loss of its correlations with mood monitoring-related regional activities. Conclusion : This study showed that alteration in the resting-state activity in schizophrenia may reflect dysfunctional empathy and distorted characteristic of emotional awareness. However, the resting-state activity may not reflect the relationship between emotional awareness and empathy.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.7-13
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• 2017

In this study, changes in gene expression after administration of silk fibroin fragments ($size{\approx}30kDa$) were evaluated in MG63 cells using a cDNA microarray assay. In addition, the level of alkaline phosphatase (ALP) activity and cellular proliferation in the group administered moderately sized silk fibroin fragments ($size{\approx}30kDa$) (MSF) were compared to those in the group administered smaller silk fibroin fragments (size < 1 kDa) (SSF). The results of the cDNA microarray assay show increased expression of genes that are related to the cell cycle and inflammation. ALP, bone morphogenetic protein-7, bone morphogenetic protein receptor type IA, and runt-related transcription factor 2 exhibited significantly lower expression compared to control cells (fold ratio < 0.5). Relative ALP activity of the $100{\mu}g/mL$ MSF group was significantly lower than that of the SSF group (P < 0.05). Thus, the MSF group showed increased expression of genes associated with cellular proliferation and inflammation but decreased expression of genes associated with osteogenesis.

• Journal of the Korean Chemical Society
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• v.43 no.2
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• pp.225-230
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• 1999

The inquiry activities closely related to chemistry which were presented in the 4 middle school science textbooks were compared and analyzed. The total volume of chemistry part was 64.8 pages (22.3%), which were the smallest one in the four categories of science. The total numbers of inquiry activities related to chemistry were 171; 59 for the first grade, 47 for the second, and 65 for the third grade and those were composed of 29 observations, 20 measurements, 113 experiments, 9 data explanations, no investigation and discussion. Therefore, the major inquiry activity was experiment (66.7%) and this maldistribution will need to be improved.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.29-40
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• 2000

Highly purified Cerrena unicolor laccase (benzenediol:oxygen oxidoreductase, EC 1.10.3.2) caused the demethoxylation of milled wood lignin and several lignin related substances. The constitutive form of the enzyme produced extracellularly by C. unicolor fermenter culture was isolated and purified by ion-exchange chromatography on the DEAE-Toyopearl column and by affinity chromatography on a ConA-Sepharose and Syringyl-AH-Sepharose 4B columns. The enzyme was further immobilized on functionalized porous glass (CPG) and keratin coated CPG. The demethylating activity was monitored both by estimation of released methanol and by detection of the level of methoxyl groups (also in some water miscible solvents) after incubation of lignin materials with laccase preparations (free and immobilized). The effects of the incubation time and temperature on the demethoxylating activity of immobilized laccase preparations were also studied.

• Korean Journal of Pharmacognosy
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• v.29 no.1
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• pp.28-34
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• 1998

It has been known that diseases related with aging or cancer result, at least in part, from free radicals, and antioxidants may reduce or prevent the abnormalities associated with free radical formation via its scavenging action. Thus, this study was carried out to investigate the antioxidative and antimicrobial activities of nut species for the purpose of developing antioxidant from natural products. Antioxidant activities of four kinds of nuts such as chestnut, groundnut, walnut and acorn were examined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The extracts from chestnut hull and acorn barnyard millet showed strong antioxidative activities among 10 samples tested. Because of their highest antioxidative activity among 10 samples, radical scavenging effects of 4 different extract compartments (Hexane, EtOAc, BuOH and $H_2O$ extracts) from chestnut hull and acorn barnyard millet, were further examined by DPPH method. EtOAc and BuOH extracts exhibited antioxidative activities similar to those of natural, tocopherol or synthetic antioxidants, BHA. These findings demonstrates that major fraction of the antioxidative activity of chestnut hull or acorn barnyard millet was the EtOAc and BuOH extract compartments. However, antimicrobial activities against food-related bacteria and yeasts was relatively weak.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.447-451
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• 2021

In this study, we discovered for the first time that linarin, a flavonoid compound, enhances melanin biosynthesis in B16F10 cells, and subsequently elucidated the underlying mechanism of linarin-induced melanogenesis. Linarin showed no cytotoxicity at a concentration of 42 μM and significantly increased intracellular tyrosinase activity and melanin content in B16F10 cells. Mechanistic analysis showed that linarin increased the expression of tyrosinase, tyrosinase-related protein 1 (TRP-1), and microphthalmia-associated transcription factor (MITF) that are related to melanogenesis. Moreover, linarin decreased the phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (AKT). Finally, we evaluated the effect of the structure-activity relationship of linarin and its aglycone on melanogenesis. The results indicated that linarin enhances the expression of melanogenic proteins by activating MITF expression via the modulation of mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K), and protein kinase B signaling pathways in B16F10 cells, thereby enhancing melanogenesis.