• Applied Biological Chemistry
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• 제27권3호
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• pp.180-186
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• 1984

비교적 높은 역가의 glucose oxidase(GOD)와 catalase(CAT)를 세포의 효소로 생산하는 균주인 Penicillium spp., PS-8을 선별배지를 사용하여 액체 배양하였으며, 그 결과 배양액 1ml당 2.7units의 glucose oxidase와 2.0units의 catalase를 얻었다. Glucose oxidase와 catalase를 분리하기 위하여 $60{\sim}90%\;(NH_4)_2SO_4$ 분별침전을 행한후 DEAE-cellulose column을 사용하여 두 효소를 완전히 분리하였으며, 이들 효소의 회수율은 54%와 34%이었다. 분리된 glucose oxidase와 catalase는 PS-8 균주를 효소 고정 매개체로 하여 2.5% glutaraldehyde를 가교제로 12시간 동안 처리함으로써 효소를 고정시켰다. 이들 고정화 효소는 CAT/GOD 값이 서로 다르게 동시 고정, 고정후 혼합, glucose oxidase만의 고정 등의 형태로 만들었다. pH에 따른 효소의 활성변화에서는 동시고정 및 고정후 혼합 방법이 수용성 효소보다 안정화됨을 보여 주었으며, 동시 고정에서는 CAT/GOD값이 높을수록 보다 완만한 pH 활성곡선을 나타내었다. GOD와 CAT/GOD=10의 Km' 값은 각각 $7.1{\times}10^{-2}$ 및 $5.1{\times}10^{-2}M$이었으며, 이들의 활성화 에너지값은 각각 3.97 및 2.98 kcal/mole/deg이었다.

• KSBB Journal
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• 제14권4호
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• pp.445-451
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• 1999

E. coli TGI/pDG7 $\alpha$ 와 빵효모의 혼합세포계에 의한 글루타치온 생산을 Aerated Slurry Bioreactor에서 수행하였다. 글루타치온 생산 효소는 34시간 동안 안정성을 보였으며, 글루타치온 수율은 4.6 mM을 유지함을 보였다. 고농도의 혼합세포를 이용한 Aerated Slurry Bioreactor에서 기질의 공급속도가 글루타치온 생산에 미치는 영향을 조사하였다. 세포가 회수되어 기질공급속도 5.2 mL/hr에서 글루타치온의 생산농도는 32시간에서 현탁반응보다 낮아짐을 보였고, 반면 세포가 회수되지 않은 기질공급속도 5.2 mL/hr에서는 22시간 동안 유지되었고 2.6 mL/hr에서는 42시간 동안 유지되었다. 글루타치온의 생산성은 기질공급속도가 10.4 mL/hr에서 25.7 mg/g wet $cell{\cdot}hr$이었으나, 2.6 mL/hr에서는 1.65 mg/g wet $cell{\cdot}hr$이었고 5.2mL/hr에서는 5.28 mg/g wet $cell{\cdot}hr$이었다. 계면활성제(Tween 80)을 사용한 경우, 글루타치온 생산시간을 25시간에서 45시간으로 연장되었다. 글루타치온 생산있어 산소가 세포계의 효소에 산소에 의해 영향을 미칠 것으로 판단되었고, 공기를 질소로 교체하여 글루타치온 생산시간을 40시간으로 연장시켰다.

• 농약과학회지
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• 제7권1호
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• pp.38-44
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• 2003

본 연구는 다양한 계열의 농약을 대상으로 체내에서 농약을 무독화하는 효소로 알려진 glutathione-S-transferase(GST) 와 esterases 에 대한 저해정도를 조사하고, 이 중 저해력이 높은 약제를 선발하여 무독화 효소에 의하여 분해되는 것으로 보고된 약제와 혼합 처리하였을 때 나타나는 약효의 변화를 조사하고자 수행하였다. 무독화효소를 저해하는 농약을 선발하기 위하여 34종의 살충제와 31종의 살균제를 대상으로 glutathione-S-transferase와 esterases 에 대한 저해력을 측정한 결과, thiodicarb $(I_{50}:1.87{\times}10^{-4}M)$, thiocyclarn $(I_{50}:7.40{\times}10^{-4}M)$, dithianon $(I_{50}:7.55{\times}10^{-5}M)$, tolylfluanide $(I_{50}:8.66{\times}10^{-5}M)$은 glutathione-S-transferase의 활성을 강게 저해하였고, dichlorvos $(I_{50}:8.95{\times}10^{-8}M)$, pirimicarb $(I_{50}:2.74{\times}10^{-6}M)$, pyrazophos $(I_{50}:3.31{\times}10^{-5}M)$, benomyl $(I_{50}:4.96{\times}10^{-5}M)$은 esterases의 활성을 강하게 저해하였다. Glutathione-S-transferase를 저해하였던 thiodicarb, thiocyclarn, dithianon, tolylfluanide와 glutathione-S-transferase 에 의해 대사되는 것으로 알려진 aeephate를 혼합 (1:1)하여 배추좀나방 (Plutella xylostella L.) 에 처리하고 약효를 관찰한 결과, 각각의 단제를 처리하였을 때보다 약효가 상승되었다. 특히 dithianon과 thiocyclam을 acephate 와 혼합시 각각 7배와 4배 약효가 상승하였다. 그리고 esterase를 저해한 약제인 dichlorvos, pirimicarb, pyrazophos, benomyl 을 esterase 에 의해 대사되는 것으로 알려진 phenthoate 와 혼합하였을 경우에도 단제 처리시의 약효보다는 혼합처리시의 약효가 높았다. Phenthoate와 dichlorvos 혼합시 18배, phenthoate 와 benomyl 혼합처리시 12배의 약효상승효과가 나타났다. 본 연구의 결과들은 무독화과정 효소에 의해 무독화되는 약제를 무독화효소 저해제와 혼합처리시 약효상승이 유발된다는 것을 나타내는데, 이러한 결과들은 향후 혼합제 개발에 유용하게 사용될 수 있을 것이라 생각된다.

• 한국컴퓨터정보학회논문지
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• 제21권7호
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• pp.61-66
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• 2016

The frequency of obesity has risen dramatically in recent years but only few safe and effective drugs are currently available. In addition, obesity can induce type 2 diabetes (T2DM), hyperlipidemia and fatty liver disease. Recently, protective effect of purslane extract (PE) on obesity has been reported, but little is known about the role and mechanism of PE in obesity. This study aimed to evaluate the effect of PE on obesity and diabetes in obese mice. In addition, the effect of PE was compared with anti-obesity and diabetes drugs. High-fat diet (HFD)-induced obese mice were treated for 8 weeks with drugs as follows: PE, orlistat, metformin, voglibose or pioglitazone. While PE mixed with normal diet did not have any effects on BW in non-obese mice, PE mixed with HFD significantly reduced BW gain, insulin resistance, and glucose intolerance, without affecting food intake and appetite in obese mice. The effect was comparable to the effects of anti-obesity and diabetes drugs. Furthermore, PE significantly increased the activity of hepatocellular anti-oxidant enzymes, leading to protection of liver from oxidative stress in obese mice. These results suggest that PE treatment may be a useful tool for preventing obesity and complication of obesity.

• Archives of Pharmacal Research
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• 제28권9호
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• pp.1065-1072
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• 2005

The nascent thyroglobulin (Tg) multimer molecule, which is generated during the initial fate of Tg in ER, undergoes the rapid reductive depolymerization. In an attempt to determine the depolymerization process, various types of Tg multimers, which were generated from deoxy­cholate-treated/reduced Tg, partially unfolded Tg or partially unfolded/reduced Tg, were subjected to various GSH (reduced glutathione) reducing systems using protein disulfide isomerase (PDI), glutathione reductase (GR), glutaredoxin or thioredoxin reductase. The Tg multimers generated from deoxycholate-treated/reduced Tg were depolymerized readily by the PDI/GSH system, which is consistent with the reductase activity of PDI. The PDI/GSH-induced depolymerization of the Tg multimers, which were generated from either partially unfolded Tg or partially unfolded/reduced Tg, required the simultaneous inclusion of glutathione reductase, which is capable of reducing glutathionylated mixed disulfide (PSSG). This suggests that PSSG was generated during the Tg multimerization stage or its depolymerization stage. In particular, the thioredoxin/thioredoxin reductase system or glutaredoxin system was also effective in depolymerizing the Tg multimers generated from the unfolded Tg. Overall, under the net GSH condition, the depolymerization of Tg multimers might be mediated by PDI, which is assisted by other reductive enzymes, and the mechanism for depolymerizing the Tg multimers differs according to the type of Tg multimer containing different degrees and types of disulfide linkages.

• Asian-Australasian Journal of Animal Sciences
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• 제16권8호
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• pp.1151-1157
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• 2003

The surfactant Tween 80 was evaluated for its ability to influence cumulative gas production, cellulose digestion, and enzyme activities by mixed ruminal microorganisms grown on barley grain or Orchardgrass hay. The addition of Tween 80 at a level of 0.10% significantly (p<0.05) decreased the cumulative gas production rate from both barley grain or Orchardgrass hay substrates. However, 0.05% Tween 80 did not affect gas production rates compared to the control treatment. The addition of 0.05% Tween 80 to cultures growing on barley grain resulted in a significant increase in cellulase (90.01%), xylanase (90.73%) and amylase (487.25%) activities after 30 h incubation. Cultures utilizing Orchardgrass hay had a significant increase in cellulase (124.43%), xylanase (108.86%) and amylase (271.22%) activities after 72 h incubation. These increases in activities were also observed with cultures supplemented with 0.10% Tween 80 throughout all the incubation times tested. These results indicated that the addition of 0.05% Tween 80 could greatly stimulate the release of some of key enzymes without decreasing cell growth rate in contrast to trends reported with aerobic microorganism. Our data indicates potential uses of the surfactant Tween 80 as a feed additive for ruminant animals.

• 한국환경농학회지
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• 제24권3호
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• pp.245-252
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• 2005

The objective of the present work was to determine the corresponding uptake and assimilation of ${NO_3}^-$ in roots and shoots of leafy radish by applying of mixed amino acids (MAA). The amino acids used in this experiment were alanine (Ala), ${\beta}-alanine\;({\beta}-Ala)$, aspartic acid (Asp), asparagines (Asn), glutamic acid (Glu), glutamine (Gln), and glycine (Gly). Leafy radish was grown by conventional fertilization with macro- and micronutrients under controlled conditions. The 15-day-old seedlings were treated 0, 0.3 and 3.0 mM of MAA containing 5 mM ${NO_3}^-$ in growth medium. Nitrate uptake was determined by following ${NO_3}^-$ depletion from the uptake solution. The activity of the enzymes related to the process of ${NO_3}^-$ reduction (NR: nitrate reductase; NiR: nitrite reductase; GS: glutamine synthetase) and the content of ${NO_2}^-\;and\;{ND_3}^-$ were analyzed in shoots and roots. The results of this study showed that ${NO_3}^-$ uptake was inhibited 38% with treatment of 0.3 mM of MAA. However, there was more than three times increase of N03- uptake in 3.0 mM MAA. In addition, the enzymatic activities were positively affected by the high MAA rate. Finally, the ${NO_3}^-$ content was increased slightly both in shoots and roots of leafy radish by MAA treatments.

• Journal of Microbiology and Biotechnology
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• 제22권2호
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• pp.220-225
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• 2012

In batch culture for Poly(vinyl alcohol) (PVA)-degrading enzyme (PVAase) production by a mixed culture, higher pH (pH 7.5) was favorable for PVAase production at the prophase of cultivation, but lower pH (pH 7.0) was favorable at the anaphase. This situation was caused by the fact that the optimum pH for different key enzymes [PVA dehydrogenase (PVADH) and oxidized PVA hydrolase (OPH)] production is various. The activity and average specific production rate of PVADH reached the highest values at constant pH 7.5, whereas those of OPH appeared at pH 7.0. A two-stage pH control strategy was therefore developed and compared for its potential in improving PVAase production. By using this strategy, the maximal PVAase activity reached 2.05 U/ml, which increased by 15.2% and 24.2% over the fermentation at constant pH 7.5 and 7.0.

• 한국식품조리과학회지
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• 제21권2호
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• pp.217-224
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• 2005

The storage characteristics of frozen soy yogurt prepared with hydrolyzed soy protein isolates were evaluated. In order to facilitate lactic fermentation bacteria grow and produce lactic acid as fast rate as possible, soy protein isolate(SPI) was hydrolyzed using two kinds of proteases; bromelain and a-chymotrypsin. The cultural systems employed thereafter for lactic fermentations were Bifidobacterium bifidum or B. bifidum and Lactobacillus bulgaricus. The viable cell counts, normal- and bile acid tolerances from the mixed cultures of B. bifidum and L. bulgaricus decreased sharply during the initial first 3 days of frozen storage and then showed a gradual decrease thereafter. Melt-down percent of the all frozen products have been favorably affected as was shown by less melting at raised testing temperature during 28 days of frozen storage except for the initial 3 days during which a minor change has been observed. Among the various volatile flavor components, the contents of acetaldehyde, acetone, diacetyl and methanol generally increased during the frozen storage. In sensory test, the frozen soy yogurt prepared with a-chymotrypsin and mixed culture of B. bifidum and L. bulgaricus was the most desirable, the highest scores in sourness, bitterness and mouthfeel.

• 한국미생물·생명공학회지
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• 제52권1호
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• pp.55-64
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• 2024

The desire of modern people to maintain a healthy and beautiful appearance is increasing day by day along with the increasing interest in skin health and the demand for functional cosmetics. Accordingly, research on functional cosmetic materials with few side effects and excellent efficacy is being actively conducted. Therefore, this study tried to verify the antioxidant and whitening effects of the mixed extracts of Bixa orellana, Ammi majus, and Glycyrrhiza glabra, whose efficacy has been individually verified. Extracts (BAG-1~4) with different extraction methods such as steaming, fermentation, and ultrasonication were prepared for 3 types of natural plants, and antioxidant and whitening effects of these extracts were confirmed. For this purpose, antioxidant, tyrosinase activity, melanin production and stability experiments were conducted. Extracts (BAG-1~4) had no cytotoxicity, and antioxidant and whitening effects were confirmed. BAG-4 extracted by steaming and fermentation showed the best efficacy. It seems that enzymes such as lipase, protease, and amylase increase phenol components by various yeasts involved in the fermentation process, thereby improving antioxidant and melanin production inhibitory effects. It was confirmed that the three types of natural plant extracts could be used as safe and functional cosmetic materials.