• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1502-1507
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• 2012

The purpose of this study was to evaluate the antioxidant contents and activities of solvent fractions from methanolic extracts of cockscome flowers. The yield of methanolic extracts from cockscome flowers was 23.33%, whereas those of its solvent fractions (hexane, chloroform, ethyl acetate, butanol, and water) were 10.27, 20.00, 13.63, 17.55, and 38.54%, respectively. Total polyphenolic, flavonoid, tannin, and proanthocyanidin contents of methanolic extracts (ME) were 6.80 mg gallic acid equivalent (GAE)/g ME, 2.34 mg catechin equivalent (CE)/g ME, 6.23 mg tannic acid equivalent (TAE)/g ME, and $44.72{\mu}g$ CE/g ME, respectively. The highest total polyphenolic, flavonoid, and tannin contents of solvent fractions were 14.92 mg GAE/g solvent fraction (SF), 5.44 mg CE/g SF, and 13.38 mg TAE/g SF in the butanol fraction, respectively. The total proanthocyanidin contents were 42.47, 44.43, 50.03, 49.12, and $41.80{\mu}g$ CE/g SF, respectively. The DPPH and ABTS radical scavenging activities from cockscome flowers were 5.24 and 10.70 mg Trolox equivalent (TE)/g ME, respectively. The highest DPPH and ABTS radical scavenging activities of the solvent fractions were 12.53 and 21.09 mg TE/g SF in the butanol fraction, respectively. SOD-like activities of methanolic extracts from cockscome flowers were 7.96 units/mL, whereas those of its solvent fractions were 4.56, 6.15, 8.07, 12.36, and 5.21 units/mL, respectively. The results of this study show that notable antioxidant activities in cockscome flowers have significant health benefits.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1369-1379
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• 2014

The physicochemical characteristics and antioxidant activities of leaf, stem, and root of ginger (Zingiber officinale R.) were determined. Nutrient composition, reducing sugar, saponin, mineral, heavy metal, total phenolic and total flavonoid contents, and antioxidant activities based on DPPH radical scavenging and FRAP assay were measured. Catechins, gingerols, shogaols, and capsaicin compositions were also determined by HPLC. The contents of water, proteins, fats, carbohydrates, fiber, and ash from ginger root were 6.4, 6.8, 3.2, 65.4, 7.3, and 18.2%, respectively. Crude fiber contents of leaf and stem were 4~5 times higher than those of root (P<0.05), and reducing sugar content of stem was about 3 times higher than those of root. Crude saponin contents were in the order of stem

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.71-84
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• 2003

The metallic shell of soil-steel structures are so weak in bending moment that it should sustain the applied load by the interaction of the backfill soil around the structures. The shell can be subjected to excessive bending moment during side backfilling or under live-load when the soil cover is less than the minimum value. The current design code specifies the allowable deformation and Duncan(1979) and McGrath et al.(2001) suggested the strength analysis methods to limit the moments by the plastic capacity of the shell. However, the allowable deformation is an empirically determined value and the strength analysis methods are based on the results of FE analysis, hence the experimental verification is necessary. In this study, the full-scale tests were conducted on the high-profile arch to investigate its behaviors during backfilling and under static live-loads. Based on the measurements, the allowable deformation of the tested structure could be estimated to be 1.45% of rise, which is smaller than the specified allowable deformation. The comparison between the measurements and the results of two strength analyses indicate that Duncan underestimates the earth-load moment and overestimates the live-load moment, while McGrath et al. predicts both values close to the actual values. However, as the predicted factors of safeties using two methods coincide with the actual factor of safety, it can be concluded that both methods can predict the structural stability under live-loads adequately when the cover is less than the minimum.

• Tuberculosis and Respiratory Diseases
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• v.66 no.3
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• pp.178-185
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• 2009

Background: Epigallocatechin-3-gallate (EGCG) is the major catechin in green tea, and has shown antiproliferative, antiangiogenic, antimetastatic and cell cycle pertubation activity in various tumor models. Hypoxia can be induced because angiogenesis is insufficient for highly proliferating cancer. Hypoxia-inducible factor-1$\alpha$ (HIF-1$\alpha$) and its downstream target, vascular endothelial growth factor (VEGF), are important for angiogenesis, tumor growth and metastasis. The aim of this study was to determine how hypoxia could cause changes in the cellular phenomena and microenvironment in a non-small cell culture system and to examine the effects of EGCG on a HIF-1$\alpha$ and VEGF in A549 cell line. Methods: A549 cells, a non-small cell lung cancer cell line, were cultured with DMEM and 10% fetal bovine serum. A decrease in oxygen tension was induced using a hypoxia microchamber and a $CO_2-N_2$ gas mixture. Gas analysis and a MTT assay were performed. The A549 cells were treated with EGCG (0, 12.5, 25, 50 ${\mu}mol/L$), and then examined by real-time-PCR analysis of HIF-1$\alpha$, VEGF, and $\beta$-actin mRNA. Results: Hypoxia reduced the proliferation of A549 cells from normoxic conditions. EGCG inhibited HIF-1$\alpha$ transcription in A549 cells in a dose-dependent manner. Compared to HIF-1$\alpha$, VEGF was not inhibited by EGCG. Conclusion: HIF-1$\alpha$ can be inhibited by EGCG. This suggests that targeting HIF-1$\alpha$ with a EGCG treatment may have therapeutic potential in non-small cell lung cancers.

• Journal of Nutrition and Health
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• v.47 no.1
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• pp.1-11
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• 2014

Purpose: Several studies have proven that EGCG, the primary green tea catechin, and glucosamine-6-phosphate (PGlc) reduce triglyceride contents in 3T3-L1 adipocytes. The objective of this study is to evaluate the combination effect of EGCG and PGlc on decline of accumulated fat in differentiated 3T3-L1 adipocytes. Methods: EGCG and PGlc were administered for 6 day for differentiation of 3T3-L1 adipocytes. Cell viability was measured using the CCK assay kit. In addition, TG accumulation in culture 3T3-L1 adipocytes was investigated by Oil Red O staining. We examined the expres-sion level of several genes and proteins associated with adipogenesis and lipolysis using real-time RT-PCR and Western blot analysis. A flow cytometer Calibar was used to assess the effect of EGCG and PGluco on cell-cycle progression of differentiating 3T3-L1 cells. Results: Intracelluar lipid accumulation was significantly decreased by combination treatment with EGCG $60{\mu}M$ and PGlc $200{\mu}g/m$ compared with control and EGCG treatment alone. In addition, use of combination treatment resulted in directly decreased expression of $PPAR{\gamma}$, $C/EBP{\alpha}$, and SREBP1. In addition, it inhibited adipocyte differentiation and adipogenesis through downstream regulation of adipogenic target genes such as FAS, ACSL1, and LPL, and the inhibitory action of EGCG and PGlc was found to inhibit the mitotic clonal expansion (MCE) process as evidenced by impaired cell cycle entry into S phase and the S to G2/M phase transition of confluent cells and levels of cell cycle regulating proteins such as cyclin A and CDK2. Conclusion: Combination treatment of EGCG and PGlc inhibited adipocyte differentiation through decreased expression of genes related to adipogenesis and adipogenic and cell cycle arrest in early stage of adipocyte differentiation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.302-309
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• 2012

Effects of cultivation time on the antioxidant contents and activities of foxtail millet and proso millet were determined. The cultivation times were early-season (ES), normal-season (NS), and late-season (LS), and the cultivated varieties were Hwanggeum-cho (HGC), Cheongcha-cho (CCC), Samdamae (SDM), Gyeongkwan 1 (GK 1), Gyeongkwan 2 (GK 2), Ganghae-cho (GHC), Hwanggeum-gijang (HGG), Manhongchal-gijang (MHCG), Byeoruk-gijang (BRG), Norangchal-gijang (NRG), and Whin-gijang (WG). The total polyphenol, flavonoid, tannin content, and DPPH and ABTS radical scavenging activities of the methanolic extracts of foxtail millet and proso millet showed significant differences according to cultivation variety and time. The highest total polyphenol content of foxtail millet was 29.33 mg of gallic acid equivalent (GAE)/g of sample in GK 1 at LS, whereas that of proso millet was 23.48 mg of GAE/g of sample in BRG at LS. The highest total flavonoid content of foxtail millet was 2.12 mg of catechin equivalent (CE)/g of sample in CCC at ES, whereas that of proso millet was 4.49 mg of CE/g of sample in BRG at LS. The highest total tannin content of foxtail millet was 14.07 mg of tannic acid equivalent (TAE)/g of sample in SDM at LS, whereas that of proso millet was 15.59 mg of TAE/g of sample in BRG at LS. The highest DPPH radical scavenging activity of foxtail millet was 7.71 mg of TE/g of sample in CCC at NS, whereas that of proso millet was 12.66 mg of TE/g of sample in BRG at LS. The highest ABTS radical scavenging activity of foxtail millet was 8.05 mg of TE/g of sample in GK 1 at LS, whereas that of proso millet was 34.46 mg of TE/g of sample in BRG at LS. Generally, HGC, GK 1, and GHC had more beneficial effects at LS than ES or NS, whereas CCC, SDM, and GK 2 had more beneficial effects at NS than ES or LS, and proso millet had more beneficial effects at LS than ES or NS.

• Journal of Plant Biotechnology
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• v.29 no.4
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• pp.265-275
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• 2002

Flavonoid biosynthesis is one of the most extensively studied areas in the secondary metabolism. Due to the study of flavonoid metabolism in diverse plant system, the pathways become the best characterized secondary metabolites and can be excellent targets for metabolic engineering. These flavonoid-derived secondary metabolites have been considerably divergent functional roles: floral pigment, anticancer, antiviral, antitoxin, and hepatoprotective. Three species have been significant for elucidating the flavonoid metabolism and isolating the genes controlling the flavonoid genes: maize (Zea mays), snapdragon (Antirrhinum majus) and petunia (Prtunia hybrida). Recently, many genes involved in biosynthesis of flavonoid have been isolated and characterized using mutation and recombinant DNA technologies including transposon tagging and T-DNA tagging which are novel approaches for the discovery of uncharacterized genes. Metabolic engineering of flavonoid biosynthesis was approached by sense or antisense manipulation of the genes related with flavonoid pathway, or by modified expression of regulatory genes. So, the use of a variety of experimental tools and metabolic engineering facilitated the characterization of the flavonoid metabolism. Here we review recent progresses in flavonoid metabolism: confirmation of genes, metabolic engineering, and applications in the industrial use.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.317-324
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• 2013

This study investigated the changes in physicochemical characteristics of adzuki bean (Vigna angularis var. nipponensis) tea depending on the variety and roasting times, for the development of functional foods. The levels of total polyphenol, flavonoids, and tannin contents were 12.72 mg gallic acid equivalent (GAE)/g, 3.01 mg catechin equivalent (CE)/g, and 3.56 mg tannic acid equivalent (TAE)/g, respectively, for the Jeolgangsung-ipat sample roasted for 16 min. The highest DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity was 7.81 mg Trolox equivalent (TE)/g in Bulgeun-ipat sample that was roasted for 14 min. The highest total polyphenol content in the hot water-leached liqueur of adzuki bean tea was $26.55{\mu}g$ GAE/100 mL in Yungum-pat that was roasted for 12 min. The total flavonoids and tannin contents of Whin-ipat and Jeolgangsung-ipat roasted for 10 min were $15.10{\mu}g$ CE/100 mL and $14.60{\mu}g$ TAE/100 mL, respectively. The highest DPPH and ABTS (2,2'-azino-bis-3-ethylbenzo-thiazoline-6-sulfonic acid) radical scavenging activities of hot water-leached liqueur of adzuki bean tea were 488.72 and 728.25 mg TE/100 mL, respectively, in Yungumpat roasted that was for 12 min. The results of this study show that roasted adzuki bean tea has notable antioxidant activity and is considered to have significant health benefits.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.317-323
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• 1994

Nine plant foods (persimmon leaf, perilla seed, Chinese quince, ginger root, walnut, mugwort leaf, arrowroot, buckwheat and sorghum) rich in phenolic substances were examined for their effects on the digestive enzymes, food-poisoning bacteria and mutagenicity/antimutagenicity by Ames test. Among tested samples, Chinese quince significantly inhibited the $\alpha-amylase$ activity (97%), exhibiting an uncompetitive inhibition type. Protease activity was inhibited by Chinese quince (86%), persimmon leaf (51%) and mugwort leaf (20%), in which mugwort extract exhibited a noncompetitive type. Lipase was activated >50% by all samples. The inhibition of $\alpha-amylase$ was highly correlated with the content of condensed tannin (r=0.89) and the inhibition of protease, with total phenolic content (r=0.84). Total phenolies fraction of tested samples showed the growth inhibition toward E. coli. Streptococcus faecalis and Salmonella enteritidis, in which the effect of perilla, sorghum and arrowroot was the highest for E. coli. Standard phenolics and food samples did not show any mutagenicity toward Salmonella typhimurium TA98 and TA100. Tannic acid inhibited the mutation of the two strains by benzo[a]pyrene whereas total phenolics fractions of Chinese quince and walnut exhibited antimutagenicity to a lesser extent.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.937-942
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• 2004

Physicochemical properties and mineral composition of seaweed salts prepared by incineration and osmotic dehydration methods were determined. As the incineration temperature increased, yield of seaweed salts, insoluble solids, pH, alkalinity, and oxidation-reduction potential (ORP) decreased. Alkalinity of salt prepared with sea tangle was higher than that of sea mustard. ORP decreased by incineration above $700^{\circ}C$, and was lower in salt with sea tangle. As incineration temperature increased, amounts of K and Ca in seaweed salt increased, whereas that of Mg decreased. Potassium and Ca contents of seaweed salt increased remarkably compared with those of common salt. Potassium content of sea tangle salt was higher than that of sea mustard. As incineration time increased, yield of seaweed salts, insoluble solid content, and pH decreased, whereas ORP of the salt increased. Potassium content of seaweed salt with incineration time, while Ca and Na contents decreased after incineration of 8 and 4 hr, respectively. Yield of seaweed salt by osmotic dehydration increased as immersion time in sea water increased. pH of salt from sea mustard was higher than that of sea tangle. ORP of seaweed salt dried three times was -128.8 mV, significantly lower than that of salt prepared by incineration method. As sea water immersion time increased, Mg content of seaweed salt increased significantly, while Ca content decreased. Potassium content of seaweed salt was higher in sea tangle salt. In case of salt prepared by incineration of residuals, pH increased with immersion time but ORP decreased.