• Korean Journal of Soil Science and Fertilizer
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• v.36 no.6
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• pp.437-444
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• 2003

Objective of this experiment was to investigate the role of strontium in intracellular processes in mung bean (Vigna radiata L.). Diamine oxidase (DAO) induction by $Sr^{2+}$ appeared to a decrease in putrescine levels correspondently. DAO activities in the hypocotyls were in a range of 0.5 to $1.8unit{\cdot}mg^{-1}\;protein{\cdot}min^{-1}$. The decrease in Put levels in the cotyledons might be partly resulted from Put degradation by DAO. It was observed that the accumulation of spermidine and spermine by $Sr^{2+}$ was in the range of 1 mM to 10 mM. Spermidine levels were 2 to 3 fold higher than in the absence of strontium. The increase in polyamine levels was observed not only on a basis of g fresh weight but also a RNA basis. These results demonstrated that the inhibitory action of $Sr^{2+}$ may be closely related with polyamine metabolism as well as diamine oxidation and polyamine accumulation.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1333-1338
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• 1998

Several enzymes of kimchi ingredients were assayed to improve the product quality using these quality related enzyme information. Among various hydrolases, amylase and protease were selected with respect to lactic acid fermentation. Peroxidase and ascorbic acid oxidase were studied for off flavor production and ascorbic acid destruction. The amount of protein in kimchi ingredients, specific and total enzyme activity of sample were compared. Regarding total enzyme activity of sample, ${\alpha}-amylase$ activity of salted and fermented anchovy, dried red pepper and salted and fermented shrimp were higher than other ingredients. Activity of salted and fermented anchovy was 2,790.0 units/g sample. Salted and fermented anchovy, oyster and Chinese radish showed the highest ${\beta}-amylase$ activity (4.4, 2.1, 1.0 units/g sample, respectively). Salted and fermented anchovy showed the highest protease activity of 13.4 PU/g sample, followed by salted and fermented shrimp and dried red pepper. For peroxidase, Chinese radish, cucumber, green onion showed the highest activity of 7.2, 6.8 and 5.6 units/g sample, respectively. In case of ascorbic acid oxidase, salted and fermented anchovy showed the strongest enzyme activity (331.4 units/g sample), followed by dried red pepper and salted and fermented shrimp.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.517-519
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• 1991

The effect of glucose oxidase (GO) and superoxide dismutase (SOD) on the oxidative stability of fish oil was investigated from oxygen content and peroxide value determinations of oil samples stored in vial. GO could inhibit the oxidation of the oil by removing headspace oxygen. When SOD was solubilized in the oil, peroxide value was slightly lower than that of a control, indicating that the enzyme also had an effect on retarding the oxidation.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.1-4
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• 2019

In this study, an anthracene cross-linker is introduced to enhance the catalytic activity of glucose oxidase (GOx) based catalysts and to increase the amount of enzyme loading. The crosslinked GOx is bonded with the CNT/PEI support using the electrostatic interaction (AC[CNT/PEI/GOx]). Electrochemical evaluations are done to evaluate the performance of this catalyst and the performance of CNT/PEI/GOx catalyst is also measured as a control. According to the measurements, it is confirmed that the amount of loaded GOx increases, while $K_m$ value calculated by Lineweaver-Burk plot shows that AC[CNT/PEI/GOx] ($K_m$ : 0.73 mM) is superior to CNT/PEI/GOx ($K_m$ : 1.71 mM) without cross-linking reaction. Based on these effects, it is demonstrated that the maximum power density of the enzymatic biofuel cell using AC[CNT/PEI/GOx] increases from $21.2{\mu}W/cm^2$ to $57.4{\mu}W/cm^2$.

• Tuberculosis and Respiratory Diseases
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• v.43 no.3
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• pp.420-433
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• 1996

Background : There have been many debates about the effects of nitric oxide on the neurogenic inflammation. The role of nitric oxide in the neurogenic inflammation of airways will be required a better understanding of the localization and types of nitirc oxide synthase(NOS) activity in the neurogenic inflammation of airways. Method : To investigate the role of nitric oxide in airway neurogenic inflammation, 1) the effects of neurokinin receptor antagonist (FK224) and nitric oxide synthase inhibitor, $N^{\omega}$-nitro-L-arginine (L-NNA) on plasma extravastion were evaluated in four groups of Sprague-Dawley rats ; sham operation group(sham NANC group), electrical vagal stimulation group(NANC2 group), intravenous pretreatment groups with FK224 (1mg/kg ; FK224 group), and L-NNA(1mg/kg ; L-NNA group) 15 minutes before vagal NANC stimulation. 2) NOS activity in trachea with neurogenic inflammation was localized by immunohistochemical stain. Immunohistochemical stain was performed by antibodies specific for inflammatory cells(iNOS), brain(bNOS), and endothelium (eNOS) on trachea obtained from sham NANC, NANC2, and FK224 groups. Results : The results are that plasma extravsation in neurogenic inflammation of rat airways was inhibited by FK224, but enhanced by L-NNA pretreatment(P<0.05). There was significantly increased infiltration of inflammatory cells in subepithelium of neurogenic inflammatory trachea, but the reduction of subepithelial infiltration of inflammatory cells was observed after pretreatment with FK224(P<0.05). Immunostaining with anti-iNOS antibody showed strong reactivity only in infiltrated inflammatory cells in neurogenic rat trachea, and these iNOS reactivity was reduced by pretreatment with FK224. bNOS immunoreactivity was significantly increased only in the nerves both of neurogenic inflammatory and FK224 pretreated trachea compared with sham NANC trachea(p<0.05). eNOS immunoreactivity was not significant change in endothelium in neurogenic inflammation of rat trachea. Conclusion : These results suggest that nitric oxide released from iNOS in infiltrated inflammatory cells has main role in neurogenic inflammation of rat trachea. The presence of bNOS immunoreactivity in the nerves indicates that nitric oxide may be released from the nerves in rat trachea with neurogenic inflammation.

• The Korean Journal of Food And Nutrition
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• v.14 no.3
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• pp.263-268
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• 2001

NaIO$_4$-산화 전분당을 Bacillus licheniformis의 $\alpha$-아밀라아제의 반응시켜서 시프염기 형성으로 당단백질로 변형시켜서 안정성을 확인하였다. 10$0^{\circ}C$에서의 열안정성은 10분 뒤에, pH 9.7에서 변형한 효소 비변형 효소의 순으로 높았다. 그러나 변형 및 안정성에 $\alpha$-cyclodextrin($\alpha$-CD)을 사용한 결과 큰 차이는 나지 않았다. pH 8.0에서 $\alpha$-CD 존재하에 변형한 효소는 pH 8~11dml 알칼리쪽에서 가장 높은 안정성을 나타냈으나, pH 5~7사이에는 다른 효소보다 낮았다. pH 9.7에서 변형하지 않은 효소는 pH 5부터 pH 13까지 서서히 증가하였고 pH 9.7에서 $\alpha$-CD존재 하의 효소는 pH 5부터 7까지 증가하다가 그 후 pH13까지 서서히 감소하였다. $\alpha$-CD존재하의 비변형 효소는 pH 7과 10에서 피크를나타낸 다음 pH12이후에는 급격히 낮아졌다. 변형한 효소는 HPLC 의 유출시간이 빨라wu서 변형하지 않은 효소보다 분자량이 큰 것으로 나타났다. 분자량 크기는 비변형 효소

• Korean Chemical Engineering Research
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• v.59 no.3
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• pp.373-378
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• 2021

The study aimed to develop a high-power enzymatic electrode for a wearable fuel cell that generates electricity utilizing lactate present in a sweat as fuel. Anode was fabricated by immobilizing lactate oxidase (LOx) on flexible carbon paper. As the lactate concentration in the electrolyte solution increased, the amount of current generated by catalysis of lactate oxidase increased. The immobilized LOx generated 1.5-times greater oxidation current density in the presence of gold nanoparticles than carbon paper only. Bilirubin oxidase (BOD)-immobilized cathode generated a larger amount of reduction current in the electrolyte saturated with oxygen than purged with nitrogen. A fuel cell composed of two electrodes was fabricated and cell voltage was measured under different discharge current. At the discharge current density of 66.7 ㎂/cm², the cell voltage was 0.5±0.0 V leading to maximum cell power density of 33.8±2.5 ㎼/cm².

• Microbiology and Biotechnology Letters
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• v.21 no.1
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• pp.23-29
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• 1993

A bacterial strain. producing a nucleoside oxidase was isolated from soil and identified as Flavobacterium meningosepticum by its taxonomical characteristics. The enzyme has been purified ISO-fold to electrophoretic homogeniety in an overall yield of 18% from the cell free extract of the producer. The enzyme catalyzed oxidation of only nucleosides related to both purine and pyrimidine with very high substrate specificity. The nucleoside oxidase was proved to be a noble enzyme by stoichiometry that 1 mol adenosine as a substrate was especially oxidized via adenosine 5' -aldehyde to 1 mol adenosine 5' -carboxylic acid with the formation of 2 mol $H_20_2$

• KSBB Journal
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• v.15 no.2
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• pp.145-149
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• 2000

Methyl mercaptan oxidase was isolated and purified from Thiobacillus thiooxidans KCTC2505 for the detection of mercaptans. T The produre of purification involved DEAE-Sephacel and Superose 12 column chromatographies with recovery yields of 40 a and 6.3%, and specific activity of 19.7 and 80.1 units/mg-protein, respectively. The molecular weight of purified methyl m mercaptan oxidase was determined to be 68.1 kDa by SDS-PAGE. The extract from DEAE-Sephacel column chromatography h had a high activity in oxidizing methyl mercaptan to produce formaldehyde which can be easily detected by purpald-coloring m method. Optimum temperature for activity was observed at $43^{\circ}C$. This enzyme was activated by $NH_4CI and (NH_4)_2S0_4$, and | inhibited by KCI and NaC!.

• The Journal of Natural Sciences
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• v.14 no.2
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• pp.55-65
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• 2004

A thiol-specific antioxidant(TSA) protein was purified from Earthworm, Lumbricus terrestris by DEAE-Cellulose, Phenl sepharose, Sephacryl S-200 gel filtration and HPLC S-300 Column Chromatography. This protein showed a thiol-specific antioxidant activity against inactivation of glutamine synthetase by a metal-catalysed oxidation system capable of generation reaction oxygen species. The molecular mass of the protein was determinated to be 51-kDa by SDS-polyacrylamide gel electrophores. Taken together, the purified TSA protein could be a new member of TSA family.