• Journal of Life Science
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• v.20 no.9
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• pp.1332-1338
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• 2010

To elucidate the mechanism underlying the regulation of hST8Sia I gene expression in FenR-induced SH-SY5Y cells, we characterized the promoter region of the hST8Sia I gene. Functional analysis of the 5'-flanking region of the hST8Sia I gene showed that the -1146 to -646 region functions as the FenR-inducible promoter of hST8Sia I in SH-SY5Y cells. Site-directed mutagenesis indicated that the NF-&B binding site at -731 to -722 was crucial for the FenR-induced expression of hST8Sia I in SH-SY5Y cells. To investigate which signal transduction pathway was involved in FenR-stimulated induction of hST8Sia I in SH-SY5Y cells, we performed Western blot analysis using phospho-specific antibodies in order to measure their degree of regulatory phosphorylation. Phosphorylations of AKT and RelA (p65) subunit of NF-${\kappa}B$ were significantly elevated in cytosolic and nuclear fractions of FenR-stimulated SH-SY5Y cells, respectively, than in control or DMSO-treated SH-SY5Y cells. These results suggest that FenR induce transcriptional up-regulation of hST8Sia I gene expression through translocation of RelA (p65) subunit of NF-${\kappa}B$ to nucleus by AKT signal pathway in SH-SY5Y cells.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.55-60
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• 2005

The murine dopamine receptor regulating factor (DRRF) gene is transcribed from a TATA-less promoter that has several putative Sp1 binding sites. The present investigation identifies functional transcription factors that modulate the expression of this gene, In the $D_2-expressing$ NB41A3 cells, Spl potently activates transcription from the DRRF promoter in pCAT-DRRF-1153/+17, but DRRF effectively inhibits it. Deletion of the 31 bp fragment between -1153 and -1122 decreased transcription down to about $60\%$. This fragment contains a functional API binding site. In addition, deletion of the 129 bp region between -901 and -772 further decreased transcription. The latter region has a functional AP2 binding site. Using a DRRF_AP1 (bases -1153 to -1121) probe, a specific retarded band was observed, and the unlabeled AP1 consensus competitor could effectively compete away this retarded band. In addition, using a DRRF_AP2 (bases -873 to -846), a specific retarded band was observed, and the unlabeled AP2 consensus competitor could effectively compete away this retarded band. The present observations suggest that Spl and DRRF regulate the DRRF promoter and that both API and AP2 also modulate this gene.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.369-377
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• 2006

Protopectinase (PPase) from Bacillus subtilis was used to investigate enzymatic maceration of vegetable tissues. Optimum concentration and pH of PPase were 0.75, 0.75, and 0.5%, and 5.0, 8.0, 7.0 for red pepper, garlic, and cucumber, respectively. Optimum shaking-rate, reaction time, and temperature of PPase were 250 rpm, 150 min, and $37^{\circ}C$, respectively. Yields of mechanically macerated red pepper, garlic, and cucumber were 45.8, 47.5, and 82.1%, whereas those treated with PPase were 81.8, 84, and 98%. Over 40% Vitamin C, the most unstable component during mechanical maceration, remained intact for 12 days after enzymatic treatment. Color differences $({\Delta}E)$ of mechanically macerated red pepper, garlic, and cucumber were 1.16, 2.86, and 3.27, whereas those of PPase-treated ones were 2.87, 7.68, and 5.22 after heat treatment at $100^{\circ}C$ for 20 min. Capsaicin content of mechanically macerated red pepper was 0.4 mg/100 g, whereas that treated with PPase was 1.32 mg/100 g. Viscosity of PPase-treated vegetable decreased slowly with increasing storage period, whereas that of mechanically macerated vegetable sharply decreased. These results indicate PPase treatment of vegetable could be better choice for preparation of high-values and functionally processed food and for extending preservation period.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.5
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• pp.908-915
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• 2001

In this paper, it is analyzed theoretically that the performance degradation, caused by carrier frequency offset, in an OFDM/M-ary PSK system. Then, when Turbo coding is adopted to an OFDM/M-ary PSK system, the degree of performance enhancement is evaluated. Finally, the maximum frequency offset is calculated to satisfy the BER performance required in a Turbo coded OFDM/M-ary PSK system. As results of analysis, it is shown that the more the number of M-ary is, the worse the BER performance is. Moreover, 7dB, 9dB, and 17dB of $E_b/N_o$ are required in QPSK, 8PSK and 16PSK systems, respectively in order to satisfy the error performance, $BER=10^{-3}$ for voice communication. If $E_b/N_o$ are 10㏈ and 15㏈, the frequency offset should be below 0.05 and 0.075, respectively, for voice communication. When Turbo coding is adopted to an OFDM/M-ary PSK system, the less the number of M-ary is, the greater the performance enhancement of Turbo coding is. If the number of a M-ary system of the system is below 16, it is found that required $E_b/N_o$ is about 8dB to satisfy $BER=10^{-5}$ Moreover, in the system the Turbo coding scheme, voice communication is available with greatly low$E_b/N_o$, and 8dB of $E_b/N_o$ is enough for data communication regardless of the permission range of frequency offset.

• Korean Journal of Veterinary Research
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• v.37 no.3
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• pp.541-546
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• 1997

There are two conserved regions with a significantly high amino acid sequence homology among the A subunits of STX, SLTs and ricin. To produce an inactive Verotoxin-2 (VT-2), two different mutants, pE167D and pDE5A, were constructed by site-directed mutagenesis, respectively, on the basis of the previous reports that two regions lie within the active-site clefts of the A subunits of ricin and STX family. The cytotoxicity ($10^3$ $CD_{50}/ml$) of VT-2 holotoxin with E167D mutation was reduced by $10^3$-fold compared with wild-type level. In addition, VT-2 with DE5A ($Trp_{202}GlyArgIleSer_{206}$) deletion mutation showed a significantly low cytotoxicity ($10^1$ $CD_{50}/ml$), resulting in $10^5$- and $10^2$-fold reductions, respectively, compared with the wild-type and E167D mutatant. SDS-PAGE for protein samples showed a 33-kDa band corresponding to the A subunit of VT-2. These results indicate that reduction in cytotoxic activity was affected not by amount of VT-2 protein produced but by mutation.

• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.419-424
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• 2007

The optimum sanitization conditions for fresh red pepper were acquired with hot water, ozone water, hydrogen peroxide and sodium hypochlorite. At this condition, the sanitized red pepper was frozen at $-70^{\circ}C$, stored at $-30^{\circ}C$ for 30 days and then changes of quality in each treatment were measured. Escherichia coli and coliform group were found to be negative with the conditions of 4 min hot water treatment at $95^{\circ}C$, 6 min ozone water (0.5 ppm) treatment, 12 min sanitization for 2%-hydrogen peroxide and of 4 min 3%-sodium hypochlorite treatment. Drip loss was generated highest at the hot water treatment to be 15%. The content of ascorbic acid was less than 40% of the control at all treatments except ozone water treatment. The content of cartenoids was 124.16-182.87 mg% at ozone water treatment which was found to be the least loss. The sensory evaluation showed that most treatments except ozone water treatment were significantly different to the control (p < 0.05). Therefore, ozone treatment was evaluated to be the best method for producing the sanitized fresh red pepper.

• Journal of Life Science
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• v.18 no.6
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• pp.845-851
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• 2008

${\beta}-Lactamase$, secreted from Bacillus sp. J105 strain was purified to a single band on SDS-PAGE by ammonium sulfate precipitation, ion exchange column chromatography and gel-filtration. The molecular weight of the purified enzyme was 31 kDa on SDS-PAGE and its isoelectric point was 7.35. Optimal pH and temperature for enzymatic reaction were 5 and $40^{\circ}C$, respectively. As a result of total amino acid composition analysis of the purified enzyme, Gly and Ala were occupied 14.1 and 13.3 mole %, respectively. Km and Vmax value of purified enzyme were 1.33 mM and 0.36 mM/ml using ampicillin as a substrate, respectively.

• Journal of Life Science
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• v.18 no.6
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• pp.884-890
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• 2008

Genistein, an isoflavone in soybean products, is a potential chemopreventive agent against various types of cancer. There are several studies documenting molecular alterations leading to cell cycle arrest at G2/M phase and induction of apoptosis; however, its mechanism of action and its molecular targets on the prostaglandin $E_2$ ($PGE_2$) production and telomere length regulation in human cancer remain unclear. In this study, we investigated the effect of genistein on the levels of cyclooxygenases (COXs) and telomere regulatory components of several human cancer cell lines (T24, human bladder carcinoma cells; U937, human leukemic cells; AGS, human stomach adenocarcinoma cells and SK-MEL-2, human skin melanoma cells). Genistein treatment resulted in the inhibition of cancer cell proliferation in a concentration-dependent manner. It was found that genistein treatment markedly decreased the levels of COX-2 mRNA and protein expression without significant changes in the expression of COX-1, which was correlated with a decrease in $PGE_2$ synthesis. Genistein treatment also partly inhibited the levels of human telomerase reverse transcriptase (hTERT) as well as human telomerase RNA (hTR) and telomerase-associated protein (TEP)-1, and the activity of telomerase. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of genistein.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.943-951
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• 2004

As storing ginger roots under optimum conditions takes high cost, ginger roots are commonly stored in underground tunnels where the maintenance of optimum temperature and humidity is difficult. One of the methods fur long term storage of ginger roots is freezing. The objective of this research was to evaluate effect of storage temperatures and packaging methods on the quality of minced ginger prepared with frozen stored ginger. The minced ginger prepared with frozen stored ginger at $-20^{\circ}C$ was packed in bags, glass bottles and tubes, and then stored at 5 and $-20^{\circ}C$ for quality evaluation at 4 and 15 week-intervals. The changes of surface color, total free sugars, free amino acids and volatile compounds were less in the combined treatment samples than in control during storage, regardless of the storage temperature. The tube packing was the best for maintaining quality of minced ginger during storage among tested packaging methods. Sensory results showed that the minced ginger with the combined treatment and packed in tubes could be stored at 5 and $-20^{\circ}C$ for 12 and 45 weeks, respectively, without a significant drop in palatability.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1007-1016
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• 2003

Garlic was stored at 4, 8, and $12^{\circ}C$ to investigate the development of green discoloration. Green discoloration developed after 7 day of storage ar $4^{\circ}C$, while it developed after 15 day of storage at 8 and $12^{\circ}C$. The effect of maleic hydrazide fertilization on green discoloration of garlic was not observed. Green discoloration of garlic was accelerated by gamma-radiation treatment. The addition of cysteine did not prevent green discoloration, which decreased the commercial value of the garlic due to the presence of white specks on the surface. When 3% ascorbic acid was added to the garlic, green discoloration developed in 6 and 24 hr at room temperature and $4^{\circ}C$, respectively. The tendency of garlic to discolor was also investigated at various storage temperatures. Discolored garlic stored for 30 day at low temperatures was conditioned at $20{\sim}45^{\circ}C$ for 20 day. The green discoloration of garlic conditioned at 20 and $25^{\circ}C$ did not disappear in 20 day, but disappeared in 20 day when conditioned at $30^{\circ}C$. The L, a, and b values of garlic conditioned at 35, 40, and $45^{\circ}C$ for 4 day were similar to those of normal garlic. Conclusively, our results indicated that the best method for suppressing green discoloration was conditioning discolored garlic at $35^{\circ}C$ for 4 day.