• Journal of Applied Biological Chemistry
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• v.54 no.1
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• pp.1-6
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• 2011

${\gamma}$-PGA(poly-${\gamma}$-glutamic acid) is an unusual anionic polypeptide that is made of D- and L-glutamic acid units connected by amide linkages between ${\alpha}$-amino and ${\gamma}$-carboxylic acid groups. ${\gamma}$-PGA has been isolated from many kinds of organisms. Many Bacillus strains produce ${\gamma}$-PGA as a capsular material of an extracellular viscous material. It is safe for eating as a viscosity element of fermented soybean products such as Chungkookjang and Natto. It is biodegradable, edible and nontoxic toward humans and the environment and its molecular weight varies from ten thousand to several hundred thousand depending on the kinds of strains used. Therefore, potential applications of ${\gamma}$-PGA and its derivatives have been of interest in the past few years in a broad range of industrial fields such as food, cosmetics, medicine, water-treatment, etc. In this study, a bacterium, Bacillus subtilis GS-2 isolated from the Korean traditional seasoning food, Chungkookjang could produce a large amount of ${\gamma}$-PGA with high productivity and had a simple nutrient requirement. Based on carbon utilization pattern and partial 16S rRNA sequence analysis, the GS-2 strain was identified as B. subtilis. The determination of purified ${\gamma}$-PGA was confirmed with thin layer chromatography (TLC), high performance liquid chromatography (HPLC), fourier transform infrared (FT-IR) spectra, and $^1H$-nuclear magnetic resonance ($^1H$-NMR) spectroscopy.

• The Korea Journal of Herbology
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• v.38 no.2
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• pp.1-7
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• 2023

Objectives : From this study, we sight to identify Anti-stress effect of Chenwangbosim-Dan (Tianwangbuxin-Dan) Extract∘Fermented Rice Extract (GABA : gamma-aminobutyric acid 30%) Complex Methods : In order to measure the degree of functional evaluation of tension relief due to stress, it was evaluated whether the psychological indicators VAS(Visual Analog Scale) and POMS(Profile Of Mood State) were improved. Which is generally used for stress measurement and has a high frequency of clinical use. All clinical trial subjects were required to take the drug once a day at 9 ± 30 min in the morning for 2 weeks. Results : After intake, the group that Chenwangbosim-Dan(Tianwangbuxin-Dan) Extract∘Fermented Rice Extract (GABA : gamma-aminobutyric acid 30%) Complex had a statistically significant improvement effect compared to before intake due to an improved 30.81% of the VAS scores. The POMS-T score improved 54.13%, the POMS-V score improved 117.5% and the POMS-F score improved 59%, which had a statistically significant effect compared to Placebo group (p<0.001). There is a significant difference between two group, so even considering the placebo effect, the anti stress effect was confirmed in the Chenwangbosim-Dan (Tianwangbuxin-Dan) Extract∘Fermented Rice Extract (GABA : gamma-aminobutyric acid 30%) Complex intake group. Conclusions : The above results showed that the Chenwangbosim-Dan(Tianwangbuxin-Dan) Extract∘Fermented Rice Extract (GABA : gamma-aminobutyric acid 30%) Complex had an anti-stress effect. Therefore, it is expected to be developed as a safe and comfortable mental care health functional food that can reduce the risk of drug abuse.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.384-389
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• 2014

The objective of the present study was to investigate the chemical composition of anthocyanin-enriched extract of radiation-induced blackberry (Rubus fruticosus L.) mutant (${\gamma}$-B201) as well as the protective effect of ${\gamma}$-B201 against oxidative stress in vitro. The cytotoxicity, reactive oxygen species (ROS) scavenging capacity, and DNA damage were assessed by WST-1 assay, flow cytometry, and comet assay, respectively. Lactate dehydrogenase, superoxide dismutase, and catalase activities were determined by using a commercial kit. The in vitro results showed that ${\gamma}$-B201 increased the cell viability, reduction of lactate dehydrogenase release, and intracellular ROS scavenging capacity in hydrogen peroxide ($H_2O_2$)-treated HepG2 cells. Furthermore, treatment with ${\gamma}$-B201 attenuated DNA damage in $H_2O_2$-treated HepG2 cells and treatment with ${\gamma}$-B201 restored the activity of superoxide dismutase and catalase in $H_2O_2$-treated HepG2 cells. In conclusion, the present study suggests that ${\gamma}$-B201 blackberry extract can exert a significant cytoprotective effect against $H_2O_2$-induced cell damage.

• Korean Journal of Materials Research
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• v.10 no.12
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• pp.845-852
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• 2000

Mesoporous ${\gamma}-Al_2O_3$ has been prepared by selective leaching of silica from calcined domestic kaolinite. From XRD and TG-DTA data, it was found that the microstructure of a spinel phase, consisting of ${\gamma}-Al_2O_3$ containing a small mount of amorphous silica, was obtained by calcining kaolinite samples at around $1000^{\circ}C$ for 24h. Porous ${\gamma}-Al_2O_3$ was prepared by selectively dissolving the amorphous silica in KOH solutions of 1~4M at temperatures of $25~90^{\circ}C$ for leaching time of 0.5~4h. In the case of the ${\gamma}-Al_2O_3$ obtained upon KOH treatment of 4M at $90^{\circ}C$ for 1h, it showed a very narrow unimodal pore size distribution, and also formed much mesopore at a diameter of around $40~80{\AA}$. The specific surface area was $250\textrm{m}^2/g$ and the total pore volume was $0.654\textrm{cm}^3/g$.

• Journal of Life Science
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• v.21 no.7
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• pp.997-1003
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• 2011

Menopause and obesity are associated with metabolism. The purpose of this study was to examine the changes of PPAR${\gamma}$, PGC-1(${\alpha},\;{\beta}$), NRf-1 and TFAM mRNA and mitochondria biogenesis in adipocytes and investigate the effect of swimming exercise for 6weeks on ovariectomized rats. Rats were randomly assigned to 3 groups: (1) ovariectomized rats fed with a control diet (C, n=4), (2) ovariectomized rats fed with high fat diet (H, n=4), and (3) ovariectomized rats trained to exercise and fed with high fat diet (H+EX, n=4). Exercise was performed by swimming for 5 days/wk, with a progressive increase in exercise over the course of 6 weeks. Results showed that the fat tissue weight in the H group was markedly increased (p<0.01) compared to other groups, however, regular exercise significantly decreased fat weight. The PPAR-${\gamma}$ (p<0.05), PGC-$1{\alpha}$ (p<0.01), -$1{\beta}$ (p<0.05), NRf-1 (p<0.01) and TFAM (p<0.05) mRNA expression in the adipocytes of H+EX were higher than in the H group. These results suggest that regular exercise for 6 weeks might exert positive effects by increasing PPAR-${\gamma}$, PGC-1 (${\alpha},\;{\beta}$), NRf-1 and TFAM mRNA expression and mitochondria in adipocytes. Thus, regular exercise may be helpful in the improvement of mitochondria biogenesis function in obese, ovariectomized rats.

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.1
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• pp.126-132
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• 2012

This paper suggests a design method of the model-following H${\infty}$ control system having robust performance. This H${\infty}$ control system is designed by applying genetic algorithm(GA) with reference model to the optimal determination of weighting functions and design parameter ${\gamma}$ that are given by Glover-Doyle algorithm which can design H${\infty}$ controller in the state space. These weighting functions and design parameter ${\gamma}$ are optimized simultaneously in the search domain guaranteeing the robust performance of closed-loop system. The effectiveness of this H${\infty}$ control system is verified by applying to the boiler-turbine control system.

• Journal of Microbiology and Biotechnology
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• v.6 no.4
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• pp.238-244
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• 1996

$\gamma$-Glutamyl transpeptidase ($\gamma$-GTP; EC 2.3.2.2) present in the culture filtrate of Bacillus sp. KUN-17 was purified 400-fold through a consecutive procedure including organic precipitation and column chromatography. The enzyme has an estimated molecular weight of 70, 000 and consists of hetero-subunits with molecular weights of 42, 000 and 22, 000. In vitro optimal conditions for those transfer and hydrolysis reactions appeared to be pH 7.0 at $50^{\circ}C$ and pH 8.4 at $40^{\circ}C$, respectively. The denatured enzyme recovered most of its $\gamma$-GTP activity by removing detergents such as sodium dodecyl sulfate (SDS) or urea with dialysis. The enzyme showed higher affinities against a number of amino acids as $\gamma$-glutamyl acceptors than glycylglycine in the following order: L-valine, L-methionine, L-glutamic acid or L-as-paragine, L-alanine. Also, it was shown that L-glutamine was the most suitable $\gamma$-glutamyl donor for the transfer reaction among those tested. Amino acids generally inhibited the enzyme activity for the transfer reaction, but not for the hydrolysis reaction.

• Journal of the Korean Society of Safety
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• v.24 no.2
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• pp.100-104
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• 2009

In this study, the space gamma dose rates in the apartments structured with concrete were measured in accordance with construction year. In addition, the environmental radiation rates coming from the subway platforms and the road tunnels were analyzed in the equivalent dose by multiplying the absorbed dose with the radiation weighting factors. The space gamma dose rates measured in apartments were higher than those of outdoor which was $0.08{\sim}0.11uSv/h$ in the natural conditions. Especially, the older construction year is, the higher becomes space gamma dose rate. The average gamma dose rates in the subway platforms were measured. In the case of Busan and Daegu subway, the earlier the opening year is, the higher becomes dose rate. However, the dose rates of Seoul subway Lines were high overall, regardless of opening year. Seoul subway Line 6 showed the highest value of 0.21uSv/h. The gamma dose rate in road tunnels was higher than one of the outdoor and increased with opening year like as apartment. In dose rate comparison of the concrete structures with the outdoor, therefore, the space gamma dose rate of indoor is higher than one of the outdoor and the older structures have a higher dose rate.

• Bulletin of Food Technology
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• v.17 no.4
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• pp.98-106
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• 2004

Two mutant enzymes of $\gamma$-glutamylcysteine synthetase ($\gamma$-GCS) which catalyzed the synthesis of $\gamma$-glutamylcysteine from L-glutamic acid and L-cysteine in the presence of ATP, were prepared bypoint mutation of $\gamma$-GCS gene with site-directed mutagensis in E. coli. Conformational structuresand catalytic reaction kinetics of mutant enzymes were compared with wild type $\gamma$-GCS afterpurification. The S495F mutant enzyme (serine at 495 residue was substituted with phenylalanine),which had no catalytic activity for $\gamma$-glutamylcysteine synthesis, rarely folded even in neutral pH.However, the mutant A494V (alanine of 494 residue was replaced by valnine) which showed 50 %increase of activity, had a high folding structure. The folding structure of A494V also more stable athigh temperature and extreme pH compared to wild type and S495F. Reaction kinetics of wild typeand A494V were also investigated, Km value of A494V was smaller than that of wild type, while itshowed a little difference at Vmax values. This result evolved that alanine at 494 may be involved inbinding site of substrate rather than catalytic site. In addition, change of catalytic activity by onepoint mutation was highly correlated with the folding structure of enzyme.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.1
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• pp.91-98
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• 1997

Y-zeolite and ${\gamma}$-Al$_2$O$_3$ were used as supports on CO and $C_3$H$_{6}$ oxidation for diesel emission control. The catalysts composed of Pd and Pt as active components were wash coated on honeycomb type ceramic substrate. The oxidation of CO and $C_3$H$_{6}$ was carried out over prepared honeycomb in a fixed bed continuous reactor in the temperature range of 20$0^{\circ}C$~50$0^{\circ}C$ and 20,000 GHSV (h$^{-1}$ ). Surface area of Y-zeolite was larger than that of ${\gamma}$-Al$_2$O$_3$ due to channel structure of Y-zeolite. Therefore, high conversion of CO and $C_3$H$_{6}$ could be obtained because of good dispersion of active metals over Y-zeolite. The honeycomb used Y-zeolite as a support showed higher $C_3$H$_{6}$ conversion than that of ${\gamma}$-Al$_2$O$_3$ due to better cracking and isomerization activity of Y-zeolite. PdPt catalyst showed high conversion of CO and $C_3$H$_{6}$ at low temperature region, 20$0^{\circ}C$~30$0^{\circ}C$, for their synergy effects. PdPt/Y-Zeolite catalyst could achieve more than 80％ conversion of $C_3$H$_{6}$ at 30$0^{\circ}C$. The use of Y-zeolite as a support increased CO and $C_3$H$_{6}$ conversion, and decreased SO$_2$ conversion very effectively. Y-zeolite found to have a good adaptability as a support for the diesel emission after treatment system.