• 한국식품과학회지
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• 제48권3호
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• pp.296-300
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• 2016

The effect of different temperatures (45, 55, 65, and $75^{\circ}C$) on the extraction of ${\beta}$-glucan and the properties of extracted ${\beta}$-glucan were investigated with four different varieties of barley. Jeju naked barley, blue barley, beer barley, and black barley contained 6.85, 5.13, 3.58, and 4.16% of ${\beta}$-glucan, respectively. ${\beta}$-glucan in barley was extracted in the range of 64.88 to 93.84% depending on the extraction temperature and barley variety. The ${\beta}$-glucans in Jeju naked barley, Jeju blue barley, and black barley were optimally extracted at $65^{\circ}C$ for 3 h and Jeju beer barley at $75^{\circ}C$. The extracted ${\beta}$-glucan resolubilized to 43.48-81.73% and the ratio of ${\beta}(1{\rightarrow}3)$ to ${\beta}(1{\rightarrow}4)$ linkage was in the range of 1:3.8-5.8. These results suggest that purification and properties of ${\beta}$-glucan depend not only on the water extraction temperature, but also on the barley variety.

• 한국축산식품학회지
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• 제20권1호
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• pp.30-35
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• 2000

The method used to remove cholesterol from egg by using $beta$-cyclodextrin was relatively stable and efficient. The aim of this study was to cost down by recycling $\beta$-cyclodextrin used to remove cholesterol from egg yolk because $\beta$-cyclodextrin was expensive. The solvents used to separate $\beta$-cyclodextrin from $\beta$-cyclodextrin complex containing egg yolk cholesterol were butanol, chloroform, ether, hexane, methanol, 2-propanol and their mixture. The ratio of solvent and complex varied from 2 : 1 to 10 : 1. The condition of mixing time and temperature varied from 30 to 60$^{\circ}C$ and from 10 minutes to 3 hours to remove cholesterol from $\beta$-cyclodextrin complex. When the ratio of choloroform and methanol was 1 : 1, the removal efficiency of cholesterol was 98.8%. The efficiency of cholesterol removal was improved when the ratio of solvent : complex increased to 4 : 1. When mixing time and temperature was up to for 1hr, at 50$^{\circ}C$ respectively, the efficiency of cholesterol removal improved to 99%. It concluded that the efficiency of cholesterol removal of 50% renewed one contained $\beta$-cyclodextrin were 81.1% while the cholesterol removal efficiency of 100% renewed $\beta$-cyclodextrin was 24% if cholesterol removal efficiency of new $\beta$-cyclodextrin were 100%.

• 대한수학회보
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• 제52권1호
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• pp.105-123
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• 2015

Let $f_{\beta}=h_{\beta}+\bar{g}_{\beta}$ and $F_a=H_a+\bar{G}_a$ be harmonic mappings obtained by shearing of analytic mappings $h_{\beta}+g_{\beta}=1/(2isin{\beta})log\((1+ze^{i{\beta}})/(1+ze^{-i{\beta}})\)$, 0 < ${\beta}$ < ${\pi}$ and $H_a+G_a=z/(1-z)$, respectively. Kumar et al. [7] conjectured that if ${\omega}(z)=e^{i{\theta}}z^n({\theta}{\in}\mathbb{R},n{\in}\mathbb{N})$ and ${\omega}_a(z)=(a-z)/(1-az)$, $a{\in}(-1,1)$ are dilatations of $f_{\beta}$ and $F_a$, respectively, then $F_a\tilde{\ast}f_{\beta}{\in}S^0_H$ and is convex in the direction of the real axis, provided $a{\in}[(n-2)/(n+2),1)$. They claimed to have verified the result for n = 1, 2, 3 and 4 only. In the present paper, we settle the above conjecture, in the affirmative, for ${\beta}={\pi}/2$ and for all $n{\in}\mathbb{N}$.

• 생약학회지
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• 제31권1호
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• pp.34-38
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• 2000

Three compounds were isolated from the roots of Astragalus membranaceus (Leguminosae). On the basis of spectroscopic evidences, the structures were characterized as $3-0-{\beta}-D-xylopyranosyl-(2',3'-O-diacetyl)-6-0-{\beta}-D-glucopyranosyl-3{\beta},6{\alpha},16{\beta},25-tetrahydroxy-20(R)$,24(S)-epoxy-cycloartane(Astragaloside I), $3-0-{\beta}-D-xylopyranosyl-(2'-O-acetyl)-6-0-{\beta}-D-glucopyranosyl-3{\beta},6{\alpha},16{\beta},25-tetrahydroxy-20(R)$,24(S)-epoxy-cycloartane(Astragaloside II), $3-0-{\beta}-D-xylopyranosyl-(2',4'-O-diacetyl)-6-0-{\beta}-D-glucopyranosyl-3{\beta},6{\alpha},16{\beta},25-tetrahydroxy-20(R)$,24(S)-epoxycycloartane(Isoastragaloside I). Full data of NMR including HMBC and 1D-TOCSY experiment of these compounds were reported for the first time.

• 한국미생물·생명공학회지
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• 제25권2호
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• pp.212-217
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• 1997

A strain of Bacillus sp. WS-14 was isolated from soil. Medium optimization for ${\beta}-mannanase$ production by Bacillus sp. WS-14 was performed. Effect of various carbon sources on ${\beta}-mannanase$ production was investigated and locust bean gum was the most effective for ${\beta}-mannanase$ production. ${\beta}-mannanase$ activity and cell growth increased with increasing the concentration of locust bean gum, however, the amounts were not significant. Among nitrogen sources, soytone was the most effective for ${\beta}-mannanase$ production. Inorganic compounds such as $KH_2PO_4,\;NaCl\;Na_2CO_3\;and\;MgSO_4{\cdot}7H_2O\;on\;{\beta}-mannanase$ production were optimized for ${\beta}-mannanase$ production. Locust bean gum of 10.0 g/l, soytone of 5.0 g/l, $KH_2PO_4$ of 2.0 g/l, NaCl of 10.0 g/l, $MgSO_4{\cdot}7H_2O\;of\;0.2\;g/l,\;Na_2CO_3$, of 2.0 g/l were selected as optimum content. Production of ${\beta}-mannanase$ by using the optimum medium was carried out. The maximum ${\beta}-mannanase$ activity of 20.8 unit/ml could be obtained after 14 h fermentation which corresponed to the productivity of ${\beta}-mannanase$ of 1.48 unit/ml-h.

• Nuclear Engineering and Technology
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• 제31권4호
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• pp.401-407
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• 1999

We have performed two experiments in the fast critical assembly BFS to measure the effective delayed neutron fraction $\beta$$_{eff}$ values and compared the results to validate the $\beta$$_{eff}$ computation code, BETA-K. Measurements of $\beta$$_{eff}$ were carried out in a metallic plutonium core and a metallic uranium core with Cf$^{252}$ source pseudo-reactivity method. Fission integrals and correction factors, which were used to obtain the experimental $\beta$$_{eff}$ values, were calculated by using the LMR core design computation code system of KAERI. BETA-K has been developed consistently with the hexagonal Nodal Expansion Method (NEM) and it used delayed neutron data of ENDF/B-VI. By comparing the computed $\beta$$_{eff}$ values with the measured ones, we found that the results from BETA-K agreed with the experimental values within the experimental error bound.ror bound.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2006년도 Spring Conference
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• pp.77-90
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• 2006

Beta-amyloid peptide (A$\beta$) is a major component of senile plaques and its aggregation is considered to play a critical role in pathogenesis of Alzheimer's disease (AD). Aggregation of A$\beta$ could result from both increased synthesis and decreased degradation of A$\beta$. Our laboratory is interested in understanding the mechanism of A$\beta$ degradation in brain. Recently our laboratory identified a bacterial gene (SKAP) from Streptomyces sp KK565 whose protein product has an activity to cleave A$\beta$ and thus reduce the A$\beta$-induced neurotoxicity. The sequence analysis showed that this gene was closely related to aminopeptidase. Maldi-Tof analysis showed that the recombinant SKAP protein expressed in E. coli cleaves both A$\beta$ 40 and A$\beta$ 42 at the N-terminal of A$\beta$ while an aminopeptidase from Streptomyces griseus (SGAP) cleaves at the C-terminal. We also identified a mammalian homolog of SKAP and the recombinant mammalian protein expressed in Sf-9 insect cells showed a similar proteolytic activity to SGAP, cutting A$\beta$ at the C-terminus. I well discuss the detailed mechanism of the enzyme action and its functional implication in AD.

• 한국동물위생학회지
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• 제21권3호
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• pp.267-275
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• 1998

돼지 수정란의 체외생산은 난자의 체외성숙과 체외수정에 관한 기술의 부족으로 아직까지 만족스럽지 못한 수준이다. 특히 돼지 수정란의 체외생산에는 복잡한 세포질의 성숙과정과 높은 다정자침입율 및 전핵형성의 억제등의 문제점이 있다. 본 연구에서는 돼지 난자의 체외성숙 체계를 개선하기 위하여 transforming growth factor$\beta$(TGF$\beta$)의 첨가가 난자 및 난구세포에 미치는 효과에 대하여 검토하였다. 체외성숙용 배지에 TGF$\beta$를 1~10ng/$m\ell$의 농도로 첨가하여 미성숙 난자를 배양한 결과 성숙율이 높아졌다. TGF$\beta$의 효과는 난구세포가 제거된 난자의 성숙에도 효과적이었다. TGF$\beta$(를 첨가하지 않은 배양액 내에서는 배양 24시간 까지 metaphase-II로 성숙된 난자가 관찰되지 않았으나 TGF$\beta$를 첨가한 배양액 내에서는 관찰되었다. 한편, 난구세포가 부착된 난자의 성숙배양시 TGF$\beta$의 첨가시기에 따른 차이는 없었으나, 난구세포를 제거한 난자의 경우에는 성숙배양 전반기(59%) 또는 후반기(57%) 24시간 동안에만 TGF$\beta$를 첨가하는 것이 48시간 동안 계속하여 첨가(27%)하는 경우 또는 비첨가(38%)에 비하여 유의적으로 높은 성숙율을 나타냈다(p<0.05). 이와 같은 결과는 난구 세포가 돼지 난자의 체외성숙에 필수적이지만 TGF$\beta$는 난구세포가 제거된 난자의 체외성숙에 어 느정도 유익한 효과를 발휘하는 것으로 추측된다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.125-125
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• 1998

Glycyrrhizin (18$\beta$-glycyrrhetic acid $\beta$-D-glucuronyl a-D-glucuronic acid, GL), a main component of liquore extract (Glycyrrhiza glabra), is ingested orally as a component in the oriental medicine. By human intestinal bacteria, glycyrrhizin (18$\beta$-glycyrrhetinic acid $\beta$-D-glucuronyl a-D-glucuronic acid, GL) was metabolized to glycyrrhetinic acid (GA): main pathway metabolizing GL to GA by glucuronidases of Bacteroides J-37 (Kim et al., 1997) and Eubacterium sp strain GLH (Akao et al., 1987) and minor pathway metabolizing GL to GA via 18$\beta$-glycyrrhetic acid D-glucuronic acid (GAMG) by $\beta$-glucuronidase of Streptococcus LJ-22 and glucuronidases of Bacteroides J-37 / E. coli. $\beta$-Glucuronidase from Streptococcus LJ-22 hydrolyzed GL to GAMG, not GA. $\beta$-Glucuronidase of Streptococcus LJ-22 hydrolyzed $\beta$-glucuronic acid conjugates of polysaccharides rather than aglycone-$\beta$-glucuronides Optimal pH of Streptococcus LJ-22 $\beta$-glucuronidase was 5-6 and its molecular weight was 250 kDaltons. Km for GL was 0.37mM.

• Archives of Pharmacal Research
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• 제22권1호
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• pp.1-8
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• 1999

Transforming growth factor-$\beta$ (TGF-$\beta$) is the prototypical multifunctional cytokine, participating in the regulation of vital cellular activities such as proliferation and differentiations as well as a number of basic physiological functions. The effects of TGF-$\beta$ are critically dependent on the expression and distribution of a family of TGF-$\beta$ receptors, the TGF-$\beta$ types I, II, and III. It is now known that a wide variety of human pathology can be caused by aberrant expression and function of these receptors. the coding sequence of the type II receptor (RII) appears to render it uniquely susceptible to DNA replication errors in the course of normal cell division. By virtue of its key role in the regulation of cell proliferation, TGF-$\beta$ RII should be considered as a tumor suppressor gene. High levels of mutation in the TGF-$\beta$ RII gene have been observed in a wide range of primarily epithelial malignancies, including colon and gastric cancer. It appears likely that mutation of the TGF-$\beta$ RII gene may be a very critical step in the pathway of carcinogenesis.