• Journal of Microbiology and Biotechnology
• /
• v.27 no.2
• /
• pp.271-276
• /
• 2017

A highly thermostable ${\beta}-(1-4)-glucanase$ (NA23_08975) gene (fig) from Fervidobacterium islandicum AW-1, a native-feather degrading thermophilic eubacterium, was cloned and expressed in Escherichia coli. The recombinant FiG (rFiG) protein showed strong activity toward ${\beta}-{\small{D}}-glucan$ from barley (367.0 IU/mg), galactomannan (174.0 IU/mg), and 4-nitrophenyl-cellobioside (66.1 IU/mg), but relatively weak activity was observed with hydroxyethyl cellulose (5.3 IU/mg), carboxymethyl cellulose (2.4 IU/mg), and xylan from oat spelt (1.4 IU/mg). rFiG exhibited optimal activity at $90^{\circ}C$ and pH 5.0. In addition, this enzyme was extremely thermostable, showing a half-life of 113 h at $85^{\circ}C$. These results indicate that rFiG could be used for hydrolysis of cellulosic and hemicellulosic biomass substrates for biofuel production.

• The Korean Journal of Pharmacology
• /
• v.21 no.2
• /
• pp.128-141
• /
• 1985

To investigate the influence of phenobarbital sodium on the action of morphine and on the diurnal rhythms of both opiate receptor binding and ${\beta}-endorphin$ contents, the amount of specifically bound $(^3H)$-morphine and immunoreactive ${\beta}-endorphin$ were measured in the midbrain of phenobarbital-treated rats at 4h intervals in a day. Rats were housed and adapted to a controlled cycle of either 12 h light-12 h dark or 24 h constant dark. After 3 weeks of adaptation, 0.5 ml of physiological saline or phenobarbital sodium (20mg/kg/day, i.p.) were administered twice a day for 2 weeks. Highly significant diurnal rhythms of opiate receptor binding and ${\beta}-endorphin$ were present in rat midbrain. In control group, the peak of maximum $(^3H)$-morphine binding was observed at 22:00 h, whereas the peak of ${\beta}-endorphin$ content was found at 06:00 h. Even in the absence of time cues these diurnal rhythms persisted, but they were highly modified with respect to the wave form as well as differences in the timing of peak and nadir. In the phenobarbital-treated group, these diurnal rhythms were also modified in shape, phase and amplitude, as well as in timing of peak and nadir. In this group, 24 h mean of opiate receptor binding was significantly decreased, while the 24 h mean level of ${\beta}-endorphin$ content was highly increased. However, Kd values in all experimental groups did not change. This indicates that differences in binding were not due to changes in the affinity, but in the number of binding sites. Statistical analysis of regression line indicates that changes of receptor binding were closely correlated with the changes of ${\beta}-endorphin$ content. These results suggest that phenobarbital may influence the action of morphine by changing the number of opiate receptors and that the modification of diurnal rhythm of opiate receptor by the agent is possibly due to changes of ${\beta}-endorphin$ content.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.14 no.4
• /
• pp.989-997
• /
• 1994

The major objective of this study is to develop an effective method to estimate ${\alpha}$ and ${\beta}$ in an aeration basin at a conventional activated sludge wastewater treatment plant. A series of unsteady state batch tests were simultaneously performed with clean water and mixed liquor in two batch reactors under identical operational conditions. Oxygen uptake rates (OURs) of the mixed liquor were measured during the tests. The results show that the OURs due to synthesis respiration and endogenous respiration were averaged about $17.96 mg/(l{\cdot}hr)$ and about $12.29mg/(l{\cdot}hr)$, respectively. The corresponding ${\alpha}$ and ${\beta}$ were ranged between 0.65 to 0.95, and between 0.88 to 0.93, respectively. Based on the overall experimental results, the proposed experimental test method and the proposed method for determination of ${\alpha}$ and ${\beta}$ are found to be relatively simple and easy to use in evaluating the characteristics of aeration systems.

• Journal of Pharmacopuncture
• /
• v.22 no.4
• /
• pp.248-252
• /
• 2019

Objectives: The aim of the present work is evaluating the special effects of Urtica Dioica and Lamium Album on the serum level of K-Ras and GSK-3 beta in diabetic rats. Methods: In the present experimental study, 32 male Wistar rats randomly divided into 4 groups (Group I: normal control rats; receiving daily PBS, Group 2: diabetic control rats; receiving single dose of streptozotocin (60 mg/kg) and daily PBS, Group 3: Diabetic rats treated with 100 mg/kg of hydroalcoholic extract of the U. dioica, Group 4: Diabetic rats treated with 100 mg/kg of hydroalcoholic extract of L. Album. Diabetes-induced by an intraperitoneal injection of streptozotocin (60 mg/ kg). On the 14 th day of treatment, the weight, fasting blood sugar (FBS) and on 28 th day blood glucose, K-Ras and GSK3 beta was measured. Results: In diabetic group blood GSK- 3 beta increase in comparison to control group (P < 0.05), also blood K-Ras decrease in the diabetic group (P < 0.05). Both extracts reduced GSK-3 beta level, however, this reduction was only statistically significant by U.dioica (P < 0.05). Compared to diabetic group, blood K-Ras level increased by both extract (P < 0.05). Also diabetes induction increase blood glucose levels and both extracts decrease its level significantly (P < 0.05).there is no significant differences among both extract effects on blood glucose, and K-Ras. Conclusion: For the first time shown that both extracts by regulating GSK-3 beta and K-Ras improve blood glucose level. More studies are needed to determine all the effects of these herbs.

• Journal of Technologic Dentistry
• /
• v.21 no.1
• /
• pp.5-14
• /
• 1999

Glass ceramics for dental crown prosthesis were prepared by crystallization of CaO-MgO-SiO2-$P_2O_5-TiO_2$ glasses. Their crystallization behaviors have been investigated as a function of heattreatment temperature, holding time and chemical composition in relation to mechinical properties. Crystallization peak temperatures were determined by differential thermal analysis(DTA). Crystalline phases and mircostructures of heat-treated sample were determined by the means of powder X-ray diffraction(XRD) and scanning electron microscopy(SEM). The final crystalline phase assemblages and the microstructures of the samples were found to be dependent on glass compositions, heattreatment temperature, and holding time. 1st crystallization peak temperature(TP), affected strongly by apatite, was found to be increased or decreased. From the experiment, the following results were obtained : 1. The crystallization peak temperature($T_P$) formed by apatite increased until adding up to 9wt% $TiO_2$ to base glass composition, then decreased above that. 2. Apatite($Ca_{10}P_6O_{25}$), whitlockite(${\beta}-3CaO-P_2O_5$), $\beta$-wollastonite($CaSiO_3$), magnesium tianate($MaTiO_3$) and diopside(CaO-MgO-$2SiO_2$) crystal phase were precipitated in MgO-CaO-$SiO_2-TiO_2-P_2O_5$ glass system containing 9wt% and 11wt% of $TiO_2$ 3. Vickers hardness of samples increased with increasing heat-treatment temperature and Vickers hardness of S415T9 samples heat-treated at 1075 was approxi-mately 813Kg $mm^{-2}$ as maximum value. 4. Vickers hardness of samples increased due to precipitation of apatite, whitlockite, $\beta$-wollastonite, magnesium titanate, and diopside crystal phases within glass matrix.

• Journal of the Korean Ceramic Society
• /
• v.29 no.2
• /
• pp.127-135
• /
• 1992

It has been reported that natural petalite showed a low negative thermal coefficient and wide coefficient and wide coexisting region with liquid phase in Li2O-Al2O3-SiO2 system. Therefore, we investigated variation of microstructure and thermal and mechanical properties when the amount of SiO2 content in petalite compound and MgO addition to it compound were changed. As SiO2 content exceeded 80 wt%, crystal phases of $\beta$-cristobalite and $\beta$-spondumene solid solution were formed. Generally, the densification and bending strength were increased by the addition of MgO, but the positive thermal coefficient was found in the case of MgO 10 wt% addition because of second phase and glassy phase.

• Food Science and Biotechnology
• /
• v.17 no.5
• /
• pp.1021-1024
• /
• 2008

Genistein, one of the isoflavones in doenjang, is generally known to prevent various cancers, osteoporosis, climacterium, and menopause symptoms, and has better bioavailability and healthful physiological effects than its glucoside, genistin. In both traditional and commercial doenjangs, genistein content ranged from 370 to 1,510 mg/kg, however, significant amounts of genistin also existed at the level of 190 to 350 mg/kg. After treating with corn $\beta$-glucosidase, over 84% of genistin in doenjang was converted to genistein. However, physiochemical characteristics such as pH, viscosity, 2-thiobarbituric acid (TBA) value, and color were not changed significantly after corn $\beta$-glucosidase treatments. Therefore, this study shows that the improved doenjang with the increased genistein content can be produced using corn $\beta$-glucosidase.

• Korean Journal of Food Science and Technology
• /
• v.34 no.4
• /
• pp.678-683
• /
• 2002

Cholesterol-lowering effects of ${\beta}-glucan-enriched$ barley fraction were investigated in rats fed 0.5% cholesterol and barley as a fiber source. Male rats of Sprague-Dawley strain were divided into six groups and fed different diets for 5 weeks: normal (cholesterol-free), control (cellulose 5%), fiber-free, and three groups containing ${\beta}-glucan-enriched$ barley fractions. Although plasma cholesterol and triglyceride levels were not significantly different among different diet groups, ${\beta}-glucan-enriched$ barley fraction-fed groups had higher HDL-cholesterol concentrations than the cellulose control group after 5 weeks of experiment. The fecal excretion of cholesterol and triglyceride was significantly increased by barley diets. Fecal concentrations of cholesterol and triglyceride in cellulose control group were 38.2 and 2.6 g/day, respectively, whereas those of barley-fed groups were $52.4{\sim}59.2$ and $6.8{\sim}9.5$ g/day, respectively, during the experimental period.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.7 no.4
• /
• pp.658-664
• /
• 1997

The effect of metal oxides($K_2O, MgO, CaO,Al_2O_3$, and $TiO_2$) on the kinds of pure $SiO_2$ phase, and $SiO_2$ phases in the composition of vitreous porcelain body was investigated. Also, the effect of the ratio $SiO_2$ to $Al_2O_3$ in the composition of porcelain body with stabilized of cristobalite phase was investigated. In the case of the addition of $K_2O, MgO, CaO, Al_2O_3$, and $TiO_2$ to pure $SiO_2$, the major phase was $\alpha$-cristobalite, $\alpha$-cristobalite, $\alpha$-quartz, $\alpha$-quartz and amorphous, respectively. As the ratio of $SiO_2$ to $Al_2O_3$ in the composition of porcelain body was decreased, the stabilization of cristobalite phase was promoted and only the critical value of $SiO_2/Al_2O_3$ ratio that stabilizing the cristobalite phase in it was 68.10/22.75. The addition of $K_2$O, MgO, CaO,Al_2O_3$, and $TiO_2$ to the composition of porcelain body stabilized already did not affect on the formation of $\alpha$-cristobalite phase which degraded the thermal properties of porcelain body, and suppressed the formation of a, $\beta$-cristobalite.

• The Journal of Engineering Research
• /
• v.1 no.1
• /
• pp.15-22
• /
• 1997

The crystallization behaviours of cordierite gel derived from sol-gel method and glass prepared from conventional melting method with or without $TiO_2$ as nucleants are compared. The densification temperature of gel is $810^{\circ}C$ and its chemical structure identified by IR analysis is same as that of glass melted by conventional method. The beginning crystallization temperature of gel is $965^{\circ}C$ lower than that of melted glass with 10wt% $TiO_2$, which is $978^{\circ}C$. The crystalline phases developed from gel during heat treatment are identified as spinel, $\beta$-quartz solid solution and $\alpha$-cordierite crystal and crystalline phases in case of glass are (Mg,Al)TiOn and $\beta$-quartz solid solution and $\alpha$-cordierite crystal, respectively. The crystallization in melted glass with nucleants occurs through bulk crystallization and in case of that without nucleants surface crystallization occurs, while the crystallization in gel is internal crystallization from interface between particles formed after densification.