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Synergistic Action Modes of Arabinan Degradation by Exo- and Endo-Arabinosyl Hydrolases

  • Park, Jung-Mi;Jang, Myoung-Uoon;Oh, Gyo Won;Lee, Eun-Hee;Kang, Jung-Hyun;Song, Yeong-Bok;Han, Nam Soo;Kim, Tae-Jip
    • Journal of Microbiology and Biotechnology
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    • v.25 no.2
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    • pp.227-233
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    • 2015
  • Two recombinant arabinosyl hydrolases, α-L-arabinofuranosidase from Geobacillus sp. KCTC 3012 (GAFase) and endo-(1,5)-α-L-arabinanase from Bacillus licheniformis DSM13 (BlABNase), were overexpressed in Escherichia coli, and their synergistic modes of action against sugar beet (branched) arabinan were investigated. Whereas GAFase hydrolyzed 35.9% of L-arabinose residues from sugar beet (branched) arabinan, endo-action of BlABNase released only 0.5% of L-arabinose owing to its extremely low accessibility towards branched arabinan. Interestingly, the simultaneous treatment of GAFase and BlABNase could liberate approximately 91.2% of L-arabinose from arabinan, which was significantly higher than any single exo-enzyme treatment (35.9%) or even stepwise exo- after endo-enzyme treatment (75.5%). Based on their unique modes of action, both exo- and endo-arabinosyl hydrolases can work in concert to catalyze the hydrolysis of arabinan to L-arabinose. At the early stage in arabinan degradation, exo-acting GAFase could remove the terminal arabinose branches to generate debranched arabinan, which could be successively hydrolyzed into arabinooligosaccharides via the endo-action of BlABNase. At the final stage, the simultaneous actions of exo- and endo-hydrolases could synergistically accelerate the L-arabinose production with high conversion yield.

Systematic Propagation of High Quality Garlic (Allium sativum L.) Through Shoot Apical Meristem Culture 1. Organogenesis from in Vitro Cultured Shoot-tips (생장점배양에 의한 우량마늘 체계적 증식 1.생장점배 양으로부터 기관형성)

  • Lee, Eun-Mo;Lee, Young-Bok
    • Korean Journal of Plant Tissue Culture
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    • v.21 no.3
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    • pp.161-166
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    • 1994
  • Since garlics (Allium sativum L.) are propagated through cloves, infection by virus or other pathogens may become severe problem if not using high quality seed bulbs every year resulting in the reduction of yield and bulb quality, In order to solve this problem, the establishment of virus-free bulb production and its supply system have been required because no chemicals were found to eliminate viruses from seed bulbs. This experiment was conducted to develop an effective production technique of high quality seed bulbs using shoot-tip culture. Over 90% of shoot-tips explanted on January L 1990 were survived at constant temperature of either 20, 24 or 28$^{\circ}C$, wheres 88% at alternate temperature (28/20$^{\circ}C$). The growth of shoot and root was most vigorous at constant 24$^{\circ}C$, and least at alternate temperature (28/20$^{\circ}C$) condition. When shoot-tips were explanted June 21 to August 1,1991, survival and growth of shoot-tips was most vigorous on MS medium supplymented with 0.1 mg/L NAA and 2 mg/L kinetin and least 1 mg/L Gh$_3$. The shoot-tips taken from the seed bulbs stored at 4$^{\circ}C$ for 15 to 60 days were placed on MS medium, shoot growth and in vitro bulblet formation increased slightly as affected by the increase of told treatment period at 4$^{\circ}C$.

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Exopolysaccharide Production and Mycelial Growth in an Air-Lift Bioreactor Using Fomitopsis pinicola

  • Choi, Du-Bok;Maeng, Jeung-Moo;Ding, Ji-Lu;Cha, Wol-Suk
    • Journal of Microbiology and Biotechnology
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    • v.17 no.8
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    • pp.1369-1378
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    • 2007
  • For effective exopolysaccharide production and mycelial growth by a liquid culture of Fomitopsis pinicola in an air-lift bioreactor, the culture temperature, pH, carbon source, nitrogen source, and mineral source were initially investigated in a flask. The optimal temperature and pH for mycelial growth and exopolysaccharide production were $25^{\circ}C$ and 6.0, respectively. Among the various carbon sources tested, glucose was found to be the most suitable carbon source. In particular, the maximum mycelial growth and exopolysaccharide production were achieved in 4% glucose. The best nitrogen sources were yeast extract and malt extract. The optimal concentrations of yeast extract and malt extract were 0.5 and 0.1%, respectively. $K_2HPO_4\;and\;MgSO_4{\cdot}7H_2O$ were found to be the best mineral sources for mycelial growth and exopolysaccharide production. In order to investigate the effect of aeration on mycelial growth and exopolysaccharide production in an air-lift bioreactor, various aerations were tested for 8 days. The maximum mycelial growth and exopolysaccharide production were 7.9 g/l and 2.6 g/l, respectively, at 1.5 vvm of aeration. In addition, a batch culture in an air-lift bioreactor was carried out for 11 days under the optimal conditions. The maximum mycelial growth was 10.4 g/l, which was approximately 1.7-fold higher than that of basal medium. The exopolysaccharide production was increased with increased culture time. The maximum concentration of exopolysaccharide was 4.4 g/l, which was about 3.3-fold higher than that of basal medium. These results indicate that exopolysaccharide production increased in parallel with the growth of mycelium, and also show that product formation is associated with mycelial growth. The developed model in an air-lift bioreactor showed good agreement with experimental data and simulated results on mycelial growth and exopolysaccharide production in the culture of F. pinicola.

Conservative treatment of Osteoporotic Compression Fractures in Thoracolumbar spine (골다공증성 흉요추부 압박 골절에서의 보존적 치료)

  • Kang, Kyu-Bok;Koh, Young-Do
    • Journal of Trauma and Injury
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    • v.18 no.2
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    • pp.107-111
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    • 2005
  • Backgrounds: To evaluate the effectiveness of conservative treatment in osteoporotic thoraco-lumbar compression fractures and to identify the factors influencing the progression of compression. Materials and Methods: From January 2003 to October 2004, Patients who were admitted to our hospital for osteoporotic thoraco-lumbar compression fractures were reviewed retrospectively with follow-up more than 12 months (ave. 14.6 months). With simple x-ray lateral view, we evaluate wedge compression ratio (WCR) and kyphotic angle (KA) at initial and final follow-up. We separate the patients into two groups baesed on the amount of progression of vertebral compression and evaluate a relation with BMD, vertebral fracture level, initial WCR, initial KA. All datas were statistically analyzed. Results: An average of T-score was -3.5 and the changes of KA between initial and final follow-up were average $3.5^{\circ}$. Compression of anterior column were progressed to 8.5%. The changes between initial and final WCR in Group I (N=24) was 17.8%, and Group II (N=18) was 3.3%. T-score in group I was -3.4 and group II was -3.8 (p=0.228). vertebral fracture level were 10 T12, 12 L1, 2 L2 in group I; 6 T12, 6 L1, 6 L2 in group II (p=0.156). Initail WCR was 0.74 in group I, 0.63 in group II, and there was statistical difference between two groups(p=0002). Initial kyphotic angle was $13.9^{\circ}$in group I, $16.2^{\circ}$in group II repectively (p=0.392). Conclusion: The conservative treatment with short-term bed rest and early embulation is effective and valuable method to patients who have osteoporotic thoraco-lumbar compression fractures. There was no statistical difference between two groups according to BMD, vertebral fracture level, KA. But in comparison with initail WCR between two groups, there was statistical difference. That means, in the case of small initial compression of anterior column, the progression of compression was bigger than else. In these patients, more strict use of appropriate brace and careful follow-up should be needed.

Pharmacokinetic Analysis of Levofloxacin in Healthy Korean Volunteers

  • Kim, Seung-Yong;Chung, Youn-Bok;Pyo, Hee-Soo;Kwon, Oh-Seung
    • Journal of Pharmaceutical Investigation
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    • v.38 no.4
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    • pp.235-240
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    • 2008
  • A sensitive and simple method of determining the plasma levofloxacin (LFX, CAS 100986-85-4) concentrations in human volunteers by liquid-liquid extraction were developed and validated by using a high-performance liquid chromatography/diode array detector. The method was also applied to pharmacokinetic study of LFX. LFX was orally administered to 8 healthy male Korean volunteers at single lowest dose of 200 mg, compared to the published reports in which more than 500 mg of LFX was orally administered. LFX in human plasma was determined. The detection limit of LFX was $0.05\;{\mu}g/mL$. $C_{max}$ value was $2.48{\pm}0.67\;{\mu}g/mL$. $AUC_{0{\to}24\;hr$} and $AUC_{0{\to}{\infty}}$ were $14.52{\pm}3.35\;{\mu}g/mL$ and $16.00{\pm}3.66\;{\mu}g{\cdot}hr/mL$, respectively. The terminal half-life was $6.87{\pm}0.46\;hr$. Our pharmacokinetic parameters were very consistent with that previously reported, showing good correlation between LFX doses and AUC ($r^2=0.995$). This method can be useful for the pharmacokinetics and bioequivalence study with relatively low dose for reducing the main side effects of LFX.

Inhibitory Effects on Cell Survival and Quinone Reductase Induced Activity of Aster yomena Fractions on Human Cancer Cells (쑥부쟁이 분획물의 in vitro 암세포증식 억제 및 QR 유도효과)

  • Jung, Bok-Mi;Lim, Sing-Sn;Park, Yun-Ja;Bae, Song-Ja
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.1
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    • pp.8-12
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    • 2005
  • This study was performed to determine the inhibitory effects on cell survival and Quinone reductase induced activity of Aster yomena (AY) on human cancer cells which, using methanol, was extracted and fractionated into five different solvent types: hexane (AYMH), ethylether (AYMEE), ethylacetate (AYMEA), butanol (AYMB) and aqueous (AYMA) partition layers. The experiment was conducted to determine cytotoxicity of various Aster yomena partition layers on HepG2, HeLa and MCF-7 cells by MTT assay. Among various partition layers of Aster yomena, A YMEE and A YMEA showed the strong cytotoxic effects on all cancer cell lines we used. The Quinone reductase (QR) induced activity on HepG2 cells, A YMH at a does of 100 $\mu$g/mL was 2.46 times more effective compared to the control value of 1.0.

Age and Growth of Spotted Halibut, Verasper variegatus (범가자미, Verasper variegatus의 연령과 성장)

  • Jeon, Bok-Soon;Park, Byung-Ha;Jeon, Im-Ki;Kang, Yong-Joo
    • Korean Journal of Ichthyology
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    • v.8 no.1
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    • pp.56-63
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    • 1996
  • Age and growth of spotted halibut, Verasper variegatus were determined using samples collected from commercial catch in the Southern Sea, Korea. Age was determined by counting the otolith annuli which were clearly defined between translucent and opaque zones, and formed between February and March. Growth of spotted halibut was expressed by the von Bertalanffy's equation as $L_t=71.07(1-e^{{\cdot}0.3036(t-0.1173)})$ for females and $L_t=57.44(1-e^{-0.2931(t+0.1590)})$ for males. Almost all the fish examined were younger than 3 years old. The oldest fish was 6 years old in female and 4 years old in male.

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Thermal Phenomenon of $BaMgAl_{10}O_{17}$:$Eu^{2+}$ Blue Phosphor by XANES and Rietveld Method

  • Kim, Kwang-Bok;Koo, Kyung-Wan;Chun, Hui-Gon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07a
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    • pp.210-213
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    • 2002
  • The blue phosphor, $BaMgAl_{10}O_{17}$:$Eu^{2+}$, showing a blue emission band at about 450 nm were prepared by solid state reaction of BaC $O_3$, A $l_2$ $O_3$, MgO and E $u_2$ $O_3$ with Al $F_3$ as a flux. The thermal quenching of BaMgAl $O_{17}$:E $u^{2+}$ phosphor significantly reduces the intensity of the blue emission. It is reduced by an amount of 50% after heating at around 800$^{\circ}C$ for 1 hr. The red emission in the 580∼720 nm region of $^{5}$ $D_{0}$\longrightarro $w^{7}$ $F_1$ and $^{5}$ $D_{0}$\longrightarro $w^{7}$ $F_2$ transition of $Eu^{3+}$ is produced from the phosphor heated above 1,100$^{\circ}C$. The EPR spectrum also reveals that some part of E $u^{2+}$ ions are oxidized to trivalent ions above 1,100$^{\circ}C$ at around 90 and 140mT. This oxidation evidence is also detected from XANES absorption spectra for $L_{III}$ shell of Eu ions: an absorption peak is at 6,977eV of E $u^{2+}$ and 6,984eV of $Eu^{3+}$. The combined X-ray and neutron data suggests that the new phase of EuMgA $l_{11}$ $O_{19}$ magnetoplumbite structure may be formed by heat treatment.eat treatment.tment.eat treatment.tment.t.

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Effect of Commercial Multi-Emulsifiers on Rheological Properties of Cake Flour (상업용 복합유화제가 박력분의 물성에 미치는 영향)

  • Bok, Jin-Hung;Hwang, Sung-Yeon;Lee, Jeong-Hoon
    • Culinary science and hospitality research
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    • v.13 no.3
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    • pp.158-165
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    • 2007
  • This study was carried out to evaluate the rheological properties of cake flour with 3% of commercial multi-emulsifiers(P company, W company, O company) based on flour. Rheological properties were analyzed by Falling number, RVA, Alveograph and Farinograph. In Falling number, viscosity of cake flour with multi-emulsifiers was increased. In RVA, initial pasting temperature was increased by adding multi-emulsifier except for W company. and peak viscosity, final viscosity and setback were increased but breakdown was decreased. In Alveogram, P and P/L value were decreased but L and G value were increased. In Farinogram, water absorption was decreased but dough development time was increased and stability was increased except for P company.

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Comparison of Jujube Extract with Tangerine Peel Extract in Lowering Plasma Lipids and Activities of Cholesterol Regulating Enzymes in Cholesterol-Fed Rats

  • Park, Myung-Sook;Bok, Song-Hae
    • Preventive Nutrition and Food Science
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    • v.6 no.2
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    • pp.122-125
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    • 2001
  • A potential mechanism through which the jujube extract might produce a cholesterol-lowering effect was compared with that of tangerine peel extract in vivo. Two extracts were prepared using ethanol. Male rats were fed a high cholesterol (1%, w/w) lab chow with jujube extract (1.2%) or tangerine peel extract (6.3%, w/w) for 3 weeks. Activities of hepatic HMG-CoA reductase (289.6$\pm$12.9 and 296.7$\pm$11.6 nmole/min/mg vs. 347.9$\pm$17.5 nmole/min/mg) and ACAT (554.8$\pm$18.2 and 451.7$\pm$19.4 nmole/min/mg vs. 602.6$\pm$21.4 nmole/min/mg) were significantly lowered by both supplements compared to the control group. These two supplements also substantially reduced the concentrations of plasma cholesterol (103.3$\pm$15.9 and 101.6$\pm$19.4 mg/dL vs. 141.6$\pm$18.1 mg/dL) and triglyceride (61.3$\pm$5.5 and 55.5$\pm$3.9 mg/dL vs. 96.0$\pm$4.2 mg/dL). The inhibition of HMG-CoA reductase resulting from the supplementation of jujube or tangerine extracts could count for the reduction in plasma cholesterol. Accordingly, lipid-lowering action of both supplements appears to be similar in high-cholesterol fed rats.

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