• Korean Journal of Microbiology
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• v.29 no.4
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• pp.258-262
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• 1991

Rate of 11.alpha.-hydroxylation of progesterone with Rhizopus nigricans was accelerated by glucose. Glucose seemed to play an important role in the formation of cofactor because its effects on the reaction were almost same as those of electron acceptors such as NADPH and $NaIO_{4}$. Rate of glucose consumption appeared to increase in proportion as the rate of hydroxylation reaction, which enhanced with increase in the glucose concentration to level off at 0.5 g/l for mycelia and at 20 g/l for spores. However, for mycelia immobilized in polyacrylamide gel, externally added glucose did not affect the reaction rate at all because of the glucose accumulated in the gel during the cultivation period. 5.alpha.-Reduction of 11.alpha.-hydroxyprogesternoe required much higher concentration of glucose than 11.alpha.-hydroxylation of progesternoe so that high yield of 11.alpha.-hydroxyprogesternoe can be obtained by repressing the activity of 5.alpha.-reductase at low concentration of glucose.

• Journal of Life Science
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• v.12 no.1
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• pp.106-112
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• 2002

Ethanol extract of Cinnamomi cortex inhibited potently cholesterol esterase activity in vitro. Chloroform fraction of ethanol extract showed the stronger inhibitory effect than other solvent fractions - ethylacetate fraction, butanol fraction, and aqueous fraction. The chloroform fraction of Cinnamomi cortex was studied as a candidator of plasma cholesterol-lowering material using high cholesterol-fed rats. In high cholesterol-fed rats, the diet with chloroform fraction of 150 mg/kg lowered not only plasma neutral lipids contents 25.1% but also plasma total cholesterol level 49.6% than only high cholesterol diet. Plasma HDL-cholesterol level in Cinnamomi cortex chloroform fraction-fed rats was recovered as those level of normal rats. LD$_{50}$ of Cinnamomi chloroform extract was calculated as 1,300 mg/kg.

• Journal of Physiology & Pathology in Korean Medicine
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• v.34 no.5
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• pp.229-237
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• 2020

The purpose of this study was to investigate the antioxidant and hangover cure effects of compound prescription containing Phyllanthus emblica and Azadirachta Indica leaf extract (CP). In vitro experiments, HepG2 cells were induced oxidative stress by hydrogen peroxide (H2O2) and treated with CP at 50, 100, 200 ㎍/㎖ concentration. Antioxidant enzyme (superoxide dismutase (SOD), catalse (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) activity and glutathione (GSH) content were decreased by hydrogen peroxide-induced oxidative stress, but CP was increased that. In vivo experiments, experiment rats were orally administered alcohol 3 g/kg and, after 30 min administered CP 200 mg/kg. After 1 and 3 h of alcohol administration, blood was collected from the tail vein, while after 5 h, blood was collected from the heart. CP modulates alcohol dehydrogenase (ADH) and acetaldehyde level, thereby decreased alcohol level in serum. Also, CP decreased the levels of aspartate aminotransferase (AST) and alkaline phosphatase (ALP). These results suggest that CP has antioxidant effects and alleviates alcohol hangover symptoms.

• Journal of Microbiology and Biotechnology
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• v.31 no.6
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• pp.867-874
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• 2021

Epalrestat (EPS) is a brain penetrant aldose reductase inhibitor, an approved drug currently used for the treatment of diabetic neuropathy. At near-plasma concentration, EPS induces glutathione biosynthesis, which in turn reduces oxidative stress in the neuronal cells. In this study, we found that EPS reduces neurodegeneration by inhibiting reactive oxygen species (ROS)-induced oxidative injury, mitochondrial membrane damage, apoptosis and tauopathy. EPS treatment up to 50 µM did not show any toxic effect on SH-SY5Y cell line (neuroblastoma cells). However, we observed toxic effect at a concentration of 100 µM and above. At 50 µM concentration, EPS showed better antioxidant activity against H₂O₂ (100 µM)-induced cytotoxicity, ROS formation and mitochondrial membrane damage in retinoic acid-differentiated SH-SY5Y cell line. Furthermore, our study revealed that 50 µM of EPS concentration reduced the glycogen synthase kinase-3 β (GSK3-β) expression and total tau protein level in H₂O₂ (100 µM)-treated cells. Findings from this study confirms the therapeutic efficacy of EPS on regulating Alzheimer's disease (AD) by regulating GSK3-β and total tau proteins phosphorylation, which helped to restore the cellular viability. This process could also reduce toxic fibrillary tangle formation and disease progression of AD. Therefore, it is our view that an optimal concentration of EPS therapy could decrease AD pathology by reducing tau phosphorylation through regulating the expression level of GSK3-β.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.5
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• pp.367-375
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• 2022

Gastric cancer stem cells (GCSCs) are a major cause of radioresistance and chemoresistance in gastric cancer (GC). Therefore, targeting GCSCs is regarded as a powerful strategy for the effective treatment of GC. Atorvastatin is a widely prescribed cholesterol-lowering drug that inhibits 3-hydroxy-3-methylglutaryl-coenzyme A reductase, a rate-limiting enzyme in the mevalonate pathway. The anticancer activity of atorvastatin, a repurposed drug, is being investigated; however, its therapeutic effect and molecular mechanism of action against GCSCs remain unknown. In this study, we evaluated the anticancer effects of atorvastatin on MKN45-derived GCSCs. Atorvastatin significantly inhibited the proliferative and tumorsphere-forming abilities of MKN45 GCSCs in a mevalonate pathway-independent manner. Atorvastatin induced cell cycle arrest at the G0/G1 phase and promoted apoptosis by activating the caspase cascade. Furthermore, atorvastatin exerted an antiproliferative effect against MKN45 GCSCs by inhibiting the expression of cancer stemness markers, such as CD133, CD44, integrin α6, aldehyde dehydrogenase 1A1, Oct4, Sox2, and Nanog, through the downregulation of β-catenin, signal transducer and activator of transcription 3, and protein kinase B activities. Additionally, the combined treatment of atorvastatin and sorafenib, a multi-kinase targeted anticancer drug, synergistically suppressed not only the proliferation and tumorsphere formation of MKN45 GCSCs but also the in vivo tumor growth in a chick chorioallantoic membrane model implanted with MKN45 GCSCs. These findings suggest that atorvastatin can therapeutically eliminate GCSCs.

• Journal of Ginseng Research
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• v.19 no.1
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• pp.31-38
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• 1995

Antioxidant effect of Korean ginseng (Panax ginseng C.A. Meyer) was investigated in rats. Long-term administration of ginseng water extract protected the activity of liver cytosotic SOD, catalase and glutathione peroxidase from being significantly decreased with advancing age (p<0.05). It was more effective toward glutathione peroxidase than other antioxidant enzymes. However, the level of sulfhydryl compounds and its related enzymes such as glutathione reductase and glutathione-5-transferase was not significantly changed by the administration of ginseng. Liver microsomal formation of reactive oxygen species such as superoxide and hydrogen peroxide did not show a significant difference between two groups although it was slightly decreased with age, but lipid peroxidizability of microsomal membrane induced by a prooxidant was slightly lower in ginseng-treated rats. Interestingly, antioxidant capacity of plasma from ginseng treated rats on autooxidation of ok-brain homogenates was much higher than that of normal ones. However, resistance of RBC membrane against oxidative stress showed a similar tendency. The content of serum TBA reactive substances lowered consistently in the rats treated with r ginseng at all corresponding age and a significant difference between two groups was found at 24 months of age (p<0.05). Ginseng extract protected lipid peroxidation in brain and liver. This protection was more effective in the stressed rats imposed by immobilization than normal ones. In conclusion, ginseng water extract protected the age related deterioration of major antioxidant enzymes, and this effect was more striking with increasing duration of treatment. This comprehensive antioxidant action of ginseng seems to be bra certain action of ginseng other than a direct antioxidant action, which might be a long term normalizing effect through the harmony of various components.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.229-229
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• 2022

Rapeseed is a crop that is waterlogging sensitive, and it is necessary to breed waterlogging tolerance varieties. Our study presents the comparative transcriptome changes in two rapeseed lines, i.e., waterlogging-tolerant (tJ8634-B-30,) and - sensitive ('EMS26') lines under control and waterlogging stress treatments at the flowering stage. RNA-sequencing analysis revealed 13,279 differentially expressed genes (DEGs) for 'J8634-B-30' and 8,682 DEGs for 'EMS26' under waterlogging stress condition compared to control. Among DEGs of 'J8634-B-30', 6,818 were up-regulated and 6,461 were down-regulated. On the other hand, among the DEGs of 'EMS26', the number of down-regulated genes (5,240) were higher than that of up-regulated genes (3,442). Gene ontology enrichment analysis showed that DEGs related to glucan metabolic, cell wall, and oxidoreductase activity were significantly changed in 'J8634-B-30'. Kyoto Encyclopedia of Genes and Genomes (KEGG)-based analysis in 'J8634-B-30' identified up-regulated DEGs being involved in MAPK signaling pathways. In addition, the DEGs belonging to mechanisms responding to waterlogging stress, i.e., plant hormones, carbon metabolism, Reactive oxygen species (ROS), Nitric oxide (NO) etc. were compared in rapeseed lines. Several DEGs including ethylene-responsive transcription factor (ERF), constitutive triple response (CTR) (in ethylene signaling pathway), monodehydroascorbate Reductase (MDAR), NADPH oxidase (in ROS pathway), cytochrome c oxidase assembly protein (COX) (in NO pathway) up-regulated in 'J8634-B-30'. These outcomes provided the valuable information for further exploring the genetic mechanism of waterlogging tolerance in rapeseed.

• Journal of Nutrition and Health
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• v.18 no.4
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• pp.272-282
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• 1985

A dietary survey by 3-day food record, clinical examination, urinary riboflavin excretion, and erythrocyte glutathione reductase activity coefficient ( EGRAC ) were measured on forty -eight female college students residing in Seoul. Thirty -one students were on normal diet and seventeen were lacto - ovo vegetarians. The results are as following : (1) Students had lower intakes of energy, similar intakes of protein and higher intake of riboflavin compared to Korean RDA for their age group. Vegetarians were lower in energy and protein intakes but were similar in RF compared to omnivores. (2) Mean EGRAC values were $1.24{\pm}0.03$ for all subjects, $1.19{\pm}0.04$ for omnivores, and $1.32{\pm}0.06$ for vegetarians. Percentages of subjects with EGRAC values above 1.2 were 65% in all subjects, 55% in omnivores, and 82% in vegetarians. Therefore, it was concluded that vegetarians were more severe in biochemical lesions than omnivores despite the fact that their RF intakes were similar to omnivores. (3) Eighteen students who had EGRAC values above 1.2 were given daily supplementation of 5mg RF for one week and EGRAC determination was repeated. They all returned to normal range. (4) Correlation analyses showed that there was no significant correlation between the EGRAC values and dietary intakes of nutrients. Possible explanations for this were given. From these results, it was concluded that even though dietary RF intakes of the subjects were higher than Korean RDA levels, biochemical deficiency among the subjects was remarkably high if the criteria of EGRAC > 1.2 were used. More investigations are necessary to establish a criteria for biochemical deficiency and RDA levels of riboflavin for Koreans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.767-774
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• 2011

Defatted green tea seed was extracted with 100% ethanol for 4 hr and then fractionated with petroleum ether, ethyl acetate and butanol. The ethanol and butanol extracts showed greater increases in antiproliferation potential against liver cancer cells than petroleum ether, ethyl acetate, $H_2O$, and hot water extracts did. Thus, this study was carried out to investigate the anti-proliferative actions of defatted green tea seed ethanol extract (DGTSE) in HepG2 cancer cells. The DGTSE contained catechins including EGC ($1039.1{\pm}15.2\;g/g$), tannic acid ($683.5{\pm}17.61\;{\mu}g/g$), EC ($62.4{\pm}5.00\;{\mu}g/g$), ECG ($24.4{\pm}7.81\;{\mu}g/g$), EGCG ($20.9{\pm}0.96\;{\mu}g/g$) and gallic acid ($2.4{\pm}0.68\;{\mu}g/g$), but caffeic acid was not detected when analyzed by HPLC. The anti-proliferation effect of DGTSE toward HepG2 cells was 83.13% when treated at $10\;{\mu}g$/mL, of DGTSE, offering an $IC_{50}$ of $6.58\;{\mu}g$/mL. DGTSE decreased CYP1A1 and CYP1A2 protein expressions in a dose-dependent manner. Quinone reductase and antioxidant response element (ARE)-luciferase activities were increased about 2.6 and 1.94-fold at a concentration of $20\;{\mu}g$/mL compared to a control group, respectively. Enhancement of phase II enzyme activity by DGTSE was shown to be mediated via interaction with ARE sequences in genes encoding the phase enzymes. DGTSE significantly (p<0.05) suppressed prostaglandin $E_2$ level, tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) protein expressions, and NF${\kappa}$B translocation, but did not affected nitric oxide production. From the above results, it is concluded that DGTSE may ameliorate tumor and inflammatory reactions through the elevation of phase II enzyme activities and suppression of NF${\kappa}$B translocation and TNF-${\alpha}$ protein expressions, which support the cancer cell anti-proliferative effects of DGTSE in HepG2 cells.

• Korean Journal of Weed Science
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• v.12 no.2
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• pp.89-101
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• 1992

In this study, various physiological and biochemical experiments were conducted to know whether the selectivity between rice and barnyardgrass treated with bleaching herbicides containing diphenyl ether compounds was also partly based on their basic physiological proterties such as peroxidation ability, membrane stability or antioxidant system. It seemed to be partly based on the differences of their physiological characteristics that barnyardgrass was commonly more susceptible to most of the bleaching herbicides than rice. The scenescence of intact leaf segment was more rapid in barnyardgrass than in rice, indicating that barnyardgrass is weak at early stage. Also pigment metabolic ability, antioxidant enzyme activities(peroxidase, catalase, superoxide dismutase, glutathione reductase) and antioxidant content (tocopherol, ascorbic acid, glutathione, carotenoids) were lower in barnyardgrass on the basic of fresh weight. However, lipoxygenase activity and the content of unsaturated fatty acid which is vulnerable to oxygen radicals were higher in barnyardgrass, suggesting that barnyardgrass seedling bave a properties easy to be peroxidized. The differences of PPIX (protoporphyrin IX) or carotenoid content, which are the primary substances inducing herbicide activity, were not related to the selectivity between rice and barnyardgrass.