• Food Science and Biotechnology
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• v.18 no.2
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• pp.570-573
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• 2009

The debranching enzyme of Nostoc punctiforme (NPDE) is a novel enzyme that catalyzes the hydrolysis of $\alpha$-1,6-glycosidic linkages in starch, followed by the sequential hydrolysis of $\alpha$-1,4-glycosidic linkages. The debranching activity of NPDE is highly specific for branched chains with a degree of polymerization (DP)>8. Moreover, the rate of hydrolysis of $\alpha$-1,4-linkages by NPDE is greatly enhanced for maltooligosaccharides (MOs) with a DP>8. An analysis of reaction mixtures containing various starches revealed the accumulation of maltooctaose (G8) with glucose and maltose. Based on the novel enzymatic properties of NPDE, an MO mixture containing more than 60% G8 with yield of 18 g G8 for 100 g starch was prepared by the reaction of NPDE with soluble starch, followed by ethanol precipitation and gel permeation chromatography (GPC). The yield of the G8-rich mixture was significantly improved by the addition of isoamylase. In summary, a 4-step process for the production of a G8-rich mixture was developed involving the enzymatic hydrolysis of starch by NPDE.

• The Korean Journal of Pharmacology
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• v.32 no.2
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• pp.139-150
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• 1996

The effects of adenosine analogues on the electrically-evoked norepinephrine(NE) release and the influence of ischemia on the effects were studied in the rat hippocampus. Slices from the rat hippocampus were equilibrated with $0.1{\mu}M$ $[^3H]-norepinephrine$ and the release of the labelled product, $[^3H]-NE$, was evoked by electrical stimulation(3 Hz, 2 ms, 5 $VCm^{-1}$ and rectangular pulses for 90 sec), and the influence of various agents on the evoked tritium-outflow was investigated. Ischemia(15min with 95% $N_2$ +5% $CO_2$) increased both the basal and evoked NE release. These increases were abolished by addition of glucose into the superfused medium, and they were significantly inhibited either by $0.3\;{\mu}M$ tetrodotoxin pretreatment or by removing $Ca^{++}$ in the medium. MK-801$(1{sim}10\;{\mu}M)$, a specific NMDA receptor antagonist, and glibenclamide $(1\;{\mu}M)$, a $K^+-channel$ inhibitor, neither alter the evoked NE release nor affected the Ischemia-Induced increases in NE release. However, polymyxin B(0.03 mg), a specific protein kinase C inhibitor, inhibited the effect of ischemia on the evoked NE release. Adenosine and $N^6-cyclopentyladenosine$ decreased the NE release in a dose-dependent manner in ischemic condition, though the magnitude of inhibition was far less than those in normal (normoxic) condition. Also the treatment with $5{\mu}M$ DPCPX, a potent $A_1-adenosine$ receptor antagonist did not affect the ischemia-effect. These results suggest that the evoked-NE release is potentiated by ischemia, and this process being most probably mediated by protein kinase C, and that the decrease of NE release mediated through $A_1-adenosine$ receptor is significantly inhibited in ischemic state.

• Molecules and Cells
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• v.22 no.1
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• pp.8-12
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• 2006

Neuron-derived orphan receptor (NOR-1) is a member of the thyroid/steroid receptor superfamily that was originally identified in forebrain neuronal cells undergoing apoptosis. In addition to apoptotic stimuli, activation of several signal transduction pathways including direct neuronal depolarization regulates the expression of NOR-1. In this study we tested whether the expression of NOR-1 is changed following transient ischemic injury in the adult rat brain. NOR-1 mRNA increased rapidly in the dentate gyrus of the hippocampal formation and piriform cortex 3 h after transient global ischemia and returned to basal level at 6 h. On the other hand, oxygen-glucose deprivation of cultured cerebral cortical neurons did not alter the expression of NOR-1. These results suggest that expression of NOR-1 is differentially regulated in different brain regions in response to globally applied brain ischemia, but that hypoxia is not sufficient to induce its expression.

• KSBB Journal
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• v.9 no.5
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• pp.475-482
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• 1994

To find out the optimum conditions for the cell growth and the synthesis of PHB in A. eutrophus, the effects of culture conditions and extracellular by-products were investigated. Glucose and$>(NH_4)_2HP0_4$were optimum carbon and nitrogen sources, respectively for cell growth of A. eutrophus. PHB accumulation was stimulated by deficiency of nutrients such as $>NH_4^{3-}, P0_4^{3-}, and Mg^{2+}$ in the medium. $>NH_4^+$, deficiency was the most suitable for PHB accumulation and PHB accumulation ratio was reached 42% of dry cell weight. The specific growth rate was increased 1.5 times by addition yeast extract in the medium, and proteins and vitamins are supposed a main factor of that effect. The extracellular products such as ethanol and butanediol were excreted under anaerobic conditions. And ethanol was found to decrease the specific growth rate.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.2
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• pp.95-102
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• 2002

DM is a systemic disease with many complications. One of them, diabetic osteopenia is important sequelae and many authors reported reduced bone mass in diabetic rats. However, in mandible, study has been rare because of its anatomical limits. So the objective of this study was to investigate bony change in mandible of diabetic rats. Thirty-two adult rats were used in this study. Half of them were male and female respectively. In sixteen rats, streptozotocin was injected intraperitoneally to induce DM and the serum glucose concentration was checked to ensure the induction of DM prior to the time of sacrifice. At 1, 2, 3, 4, 6, 8, 12, 16weeks, control group and diabetic group rats were sacrificed respectively. And then bone mineral density of mandibles and femurs of the rats was measured using dual energy X-ray absorptiometry(DEXA). In addition serum osteocalcin and urine deoxypyridinoline were measured as markers of bone formation and resoption respectively. Mandibular and femoral bone density in streptozotocin induced rats was decreased with significance statistically after 4 weeks from injection. In mandible, comparing with femur, bone density was moderately decreased. The alveolar bone in mandible was more decreased bone density than the whole body in the mandible From these results, bone mineral density decreased in uncontrolled diabetic group with time, and especially alveolar bone was more destructive in the mandible. So authors think that consideration of reduced bone mineral density is necessary in dental procedure.

• Journal of Convergence Society for SMB
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• v.5 no.4
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• pp.31-36
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• 2015

Recently, the necessity of Internet of Things in conjunction between devices is increasing. However, there are increasing security threats while applying various communication technologies in the Internet of Things. In this paper, we propose a security countermeasures to minimize damage to the security of a variety of security technologies used in the Internet of Things in order to improve the efficiency of the Internet of Things. The proposed method defined the environment to minimize security damage between home devices such as TV, washing machine, refrigerator, boiler and medical devices such as Analyzers, blood glucose meters, blood pressure monitors that are used in daily life. In addition, a variety of technologies(Zigbee, Wi-Fi, NFC, RFID, etc.) that are used in the Internet of Things may be under integrated management.

• The Korean Journal of Mycology
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• v.14 no.1
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• pp.79-84
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• 1986

A cellulose-degrading enzyme from Ganoderma lucidum was partially purified by ammonium sulfate precipitation and its enzymatic properties were studied. The enzyme had an optimum pH for activity at 4.0, and its stability range was pH $4.0{\sim}7.0$. The optimum temperature was $55^{circ}C$ and the enzyme retained 80% original activity after heated at $50^{\circ}C$ for 60 min. The activation energy of the enzyme for CMC degradation was caculated and found to be 6.2 Kcal/mole. The enzyme was activited by the addition of $Co^{++},\;Mn^{++}$, but slightly inactivated by $Hg^{++}$. Various enzyme inhibitors and chemical reagents did not affect the enzyme activity. The enzyme acted on native celluose as well as CMC. The Michaelis constant for CMC was calculated to be 2.4 mg glucose ep/ml.

• The Korean Journal of Mycology
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• v.42 no.3
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• pp.231-234
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• 2014

Six unrecorded yeasts, Cryptococcus festucosus 41-3, Cryptococcus heveanensis 56-4, Debaryomyces nepalensis 95-4, Issatchenkia occidentalis 142-1, Dioszegia zsoltii 39-1, and Kwoniella europala 47-2 were screened from 108 yeasts isolated from flowers and fruits in orchards of Yesan-gun, Chungcheongnam-do, Korea. The morphological and cultural characteristics of these unrecorded yeasts were investigated. They had various shapes, including ellipsoidal, globose, and oval, and also had budding mode in vegetable reproduction, except I. occidentalis 142-1 (fission mode). K. europaea 47-2 only formed pseudomycelium. D. zsoliti 39-1 did not grow in yeast extract-malt extract medium, potato dextrose medium, and vitamin-free medium. C. festucosus 41-3 grew well in 5% NaCl-containing yeast extract-peptone-dextrose medium and had a growth pH range of 7.0~10.0. Three unrecorded yeasts Ogataea polymorpha HB45-1, Rhodotonula hinnulla HB62-2, and Cryptococcus rajasthanensis HB80-4 were screened from 51 yeasts isolated from flowers in Hanbat arboretum in Daejeon city, Korea. They were globose in shape and did not form pseudomycelium. In addition, O. polymorpha HB45-1 and C. rajasthanensis HB80-4 had budding mode in vegetable reproduction. All of them grew well in vitamin-free medium and C. rajasthanesis HB80-4 also grew in 50% glucose and 5% NaCl-containing YPD medium.

• Korean journal of food and cookery science
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• v.31 no.6
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• pp.773-780
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• 2015

Lactic acid fermentation of black raspberry (Rubus occidentalis) juice was carried out by using the Lactobacillus plantarum GBL17 strain. The sterilized black raspberry juice was fermented using the L. plantarum GBL17 strain at $30^{\circ}C$ for 72 hours after which the total acidity increased and the pH value decreased. In addition, the highest total acidity content (2.38%) was reached, the lowest pH value (3.22) was observed, and the sugar content decreased by $9.8^{\circ}Brix$ after the 72 hour fermentation. The number of viable cells rapidly increased up until 24 hours, after which it gradually decreased. HPLC analysis of the organic acids showed 14.51 mg/g of lactic acid content in the fermented black raspberry juice, which was not detected in the non-fermented black raspberry juice (control). The content of fructose and glucose slightly decreased after fermentation. The total polyphenol and flavonoid contents of the fermented black raspberry juice increased significantly after fermentation. The DPPH radical scavenging activity of fermented black raspberry juice (70.92%) was higher than that of the control (62.96%). After lactic acid fermentation, there was no significant increase in ABTS radical scavenging activity. These results confirm that lactic acid bacteria, such as L. plantarum GBL17, showed generally higher activities with a potential as a functional beverage.

• Korean journal of food and cookery science
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• v.25 no.6
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• pp.747-757
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• 2009

The purpose of this study was to enhance the quality of kochujang Apple juice was added to traditional Kochujang at 0%, 20%, 40%, 60 and 80%. Physicochemical and microbial characteristics were periodically investigated during at room temperature during a 90 day fermentation period. The moisture content of the apple Kochujang was higher than that of the control, while the salt content of the apple Kochujang was lower than that of the control, At first, the sweetness of the apple Kochujang showed no significant difference from the control; however, its sweetness increased during the 90 days. In all treatments, the pH value decreased during the fermentation period, while the titratable acidity increased during the fermentation period. Viscosity decreased greatly after 30 days. Sugar reduction was higher in the apple Kochujang than in the control, and its concentration increased with apple juice content. According to the analysis of free sugar, glucose, fructose, and maltose had an especially high ratio in the apple Kochujang. The organic acids detected in Kochujang were citric acid, malic acid, oxalic acid and lactic acids. The content of citric acid and malic acid were higher than the other acids in the apple Kochujang. L, a, and b values generally decreased during the fermentation period. When the Kochujang was made, the number of the total viable cells was $10^7\;CFU/g$. At room temperature, the number steadily increased up to the 30th day, then steadily decreased on the 90th day. After that, there was no significant change. The number of yeasts was $10^6\;CFU/g$ at the end of the 90th day. After the 90th day of fermentation, sensory results showed that the 60~80% apple juice Kochujang showed the best taste, appearance, texture, and overall quality.