• 한국막학회:학술대회논문집
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• 한국막학회 1994년도 추계 총회 및 학술발표회
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• pp.72-73
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• 1994

Whey는 일명 lactoserum 이라고도 하며 치즈제조시 우유를 응고시키는 과정에서 Casein과 지방으로부터 분리되어 나오는 액상의 부산물로 본래 우유 부피의 약 90%를 차지하며, 용해성 단백질, 유당, 비타민과 무기질 등을 함유하고 있다. 유청에 함유되어 있는 단백질은 건조고형분의 약 13%가 되는데, 주요 단백질은 $\beta$-lactoglobulin(50%), $\alpha$-lactalbumin(22%), Serum albumin(5%), Immunoglobulin(12%), Proteose-peptone(10%) 등이 있다. 유청단백질중 가장 많이 함유되어 있는 $\beta$-lactoglobulin은 구형의 단백질로 단량체의 분자량은 약 18,400이며, pH 3.5~7 범위내에서는 해리되지 않는 이량체(dimer)를 형성한다. pH 3.5 이하에서 이량체는 해리되고 다량체의 형성으로 재평성한다. pH 7.0 이상의 알칼리 영역에서는 Conformational Change가 일어나는 것으로 알려져 있으며, 등전점(isoelectric point)은 pH 5.2이다. $\alpha$-lactalbumin은 14,200의 분자량을 가지는 구형의 단백질로 등전점은 pH 4.8이다.

• Bulletin of the Korean Chemical Society
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• 제13권1호
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• pp.83-87
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• 1992

The ring expansion of 1,3-thiazolidines 4 derived from ${\beta}$-ketoacid derivatives to the corresponding dihydro-1,4-thiazines 1 by using the action of chlorine on 4 has been achieved. In the chlorinolysis unisolable sulfenyl chlorides 5 may be formed from chlorosulfonium ions 11 by ${\beta}$-elimination involving carbonyl activated methylene hydrogens. Addition of sulfenyl chloride to the internal double bond appears to form probable thiiranium ions 14, which in turn gave 1 with loss of acidic proton. Imminium ions 15 could be hydrolyzed easily to give enol 8. As a side reaction, dihydrothiazine that was formed was further chlorinated to produce dichlorides 16 which were rearranged readily to the chloromethyl compounds 10.

• 대한의생명과학회지
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• 제25권3호
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• pp.275-281
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• 2019

This study was performed to characterize the chromosomal metallo-${\beta}$-lactamases (MBLs) of Chryseobacterium indologenes isolated from Korea and to propose a clustering method of IND MBLs based on their amino acid similarities. Chromosomal MBL genes were amplified by PCR from 31 clinical isolates of E. indologenes. Nucleotide sequencing was performed by the dideoxy chain termination method using these PCR products. Antimicrobial susceptibilities were determined by the agar dilution method. PCR experiments showed that all 31 E. indologenes isolates contained all $bla_{IND}$ genes. DNA sequence analysis revealed that E. indologenes isolates possessed ten types of $bla_{IND}$ gene, including seven novel variants ($bla_{IND-8}$ to $bla_{IND-14}$). The most common combination of MBL was IND-2 (n = 18). Minimum inhibitory concentrations of imipenem and meropenem for the isolates harboring novel IND MBLs were ${\geq}16{\mu}g/mL$. IND MBLs were grouped in three clusters, based on amino acid similarities.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.298.1-298.1
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• 2002

Tyrosinase (monophenol. 3.4-${\beta}$-dihydroxyphenylalanin oxygen oxidoreductase. EC 1.14.18.1 J. which plays a pivotal role in melanogenesis. It is single chain glycoprotein catalyzing the hydroxylation of tyrosine to ${\beta$\mid$$-3.4-dihydroxyphenylalanin (DOPA) and the oxidation of DOPA to DOPA quinone. To investigate whitening effect of chitosan oligosaccharide. we obtained chitosan oligosaccharide ［(glucosamine)2-6］ by NaNO2 oxidation and measured the effect of chitosan oligosaccharide on tyrosinase activity. Chitosan oligosaccharide dose-dependently inhibited tyrosinase (2 unit) activity and inhibited by 18.8% at dose of 100${\mu}$g/ml. Vitamin C. arbutin and kojic acid that are well known to be inhibitor of melanin production dose-dependently inhibited tyrosinase (2unit) activity. These results suggest that chitosan oligosaccharide may be used as inhibitor of melanin production in melanocyte. which will be further studied.

• Archives of Pharmacal Research
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• 제27권3호
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• pp.300-304
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• 2004

Five caffeic acid derivatives; methyl ester of caffeoylglycolic acid (1), dimethyl ester of caffeoyltartaric acid (2), dimethyl ester of caffeoyltartronic acid (3), monomethyl ester of caffeoyltartronic acid (4), methyl ester of caffeic acid (5), and some other secondary metabolites including; quercetin, quercetin 3-O-$\beta$-D-glucuronide methyl ester, kaempferol, 3,5,7,4'-O-tetramethylkaempferol, $\beta$-sitosterol glucoside, 2$\alpha$-hydroxyursolic acid and 2,24-dihydroxyursolic acid, have been isolated and characterized. All the isolated compounds were characterized with the help of NMR spectroscopy and mass spectrometry. Structure of compound 3 was also confirmed by a single X-ray crystallographic technique. Isolates were evaluated for anti-oxidant activities and most of the tested compounds were found to be potent in DPPH free radical scavenging ($IC_{50}{\;}={\;}4.56-14.17{\;}{\mu\textrm{g}}/mL$) and superoxide anion scavenging ($IC_{50}{\;}={\;}0.58-7.39{\;}{\mu\textrm{g}}/mL$) assays.

• 약학회지
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• 제59권4호
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• pp.164-169
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• 2015

In the present study, we determined the effect of $18{\beta}$-glycyrrhetinic acid ($18{\beta}$-GA) in the mice model bearing xenografts of HT-29 human colon cancer cell line. Data from the cytotoxicity assay displayed that $18{\beta}$-GA induced cell death in HT-29. The cytotoxicity was enhanced as the $18{\beta}$-GA treatment was prolonged. In case of 72 hrs treatment, $LD_{50}$ of $18{\beta}$-GA was approximately $90{\mu}M$, and the efficacy at $100{\mu}M$ of $18{\beta}$-GA appeared to be equivalent to that of doxorubicin at $1{\mu}M$. Based on the in vitro data, we tested the anti-tumor effect of $18{\beta}$-GA in thymic mice (Balb/c strain). Xenograft tumors were generated by subcutaneous injection of HT-29 ($3{\times}10^6cells/mouse$) to mice and the mice were treated intraperitoneally with $18{\beta}$-GA ($50{\mu}g/time/mouse$) every other day for 4 times. The tumor volumes were measured for a period of 14 days. Data displayed that the $18{\beta}$-GA treatment reduced the tumor volumes (P < 0.05) as compared to control mice. However, this activity was demolished when athymic mice (Balb/c nu/nu) were used instead of thymic mice. This observation appeared that T lymphocyte played an important role in the anti-tumor activity. In conclusion, our results indicate that $18{\beta}$-GA has anti-tumor activity in HT-29 tumor-bearing mice, which may be associated with T cells.

• 한국미생물·생명공학회지
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• 제40권4호
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• pp.325-332
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• 2012

본 연구는 우리나라 막걸리의 우수성을 발굴하고자 60종의 시판 생 막걸리와 저온살균 막걸리를 수집하여 이들의 주요 이화학적 성질과 젖산균 및 항고혈압활성 등의 생리기능성을 조사하였다. 생 막걸리의 에탄올 함량은 3.6%~9.6% 이었고 이들의 잔당 함량은 0.20%에서 4.52%, 아미노태질소 함량은 3.50~101.9 mg%로 다양하였다. 저온살균 막걸리의 경우 에탄올 함량은 4.0%~7.0%로 생 막걸리와 비슷하였으나 잔당함량은 0.98%~7.57%로 생 막걸리보다 높았다. 또한 시판 생 막걸리의 젖산균 생균수는 평균 $2.0{\times}10^8$ CFU/mL 이었다. 여러가지 생리기능성 중 시판 EDS-14 생 막걸리와 PWR-12 저온살균 막걸리의 항고혈압성 안지오텐신 전환효소 저해활성이 각각 89.0%와 87.0%로 매우 높았으나 여타의 생리기능성은 30% 미만으로 낮았다. 또한 ${\beta}$-Glucan 함량은 생 막걸리와 저온살균 막걸리가 각각 건조고형물 g당 평균 14.1%와 14.6%을 보였다.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2001년도 춘계심포지움 및 학술발표회
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• pp.131-131
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• 2001

내분비계장애물질에 대한 검색기법의 하나로 수컷 어류의 교배행위 및 생식력에 대한 in vivo 연구를 시도하였다. 수컷 송사리(Oryzias latipes)에 대표적 에스트로젠인 17$\beta$-estradiol를 2 및 20 $\mu\textrm{g}$/L의 농도로 각 노출군당 5마리씩 14일간 노출시킨 후 각 군당 임의로 2마리씩 선택하여 Prostaglandin F2$\alpha$를 주사한 3마리의 정상 암컷 송사리와의 교배행위를 비디오 카메라를 이용하여 1시간 동안 녹화하여 분석하였다. (중략)

• Natural Product Sciences
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• 제14권4호
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• pp.269-273
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• 2008

Microbial transformation of isoxanthohumol (1), a prenylated flavanone from hops, has resulted in the production of a pair of glucosylated derivatives. The structures of these compounds were elucidated to be (2S)-5-methoxy-8-prenylnaringenin 7-O-${\beta}$-D-glucopyranoside (2) and (2R)-5-methoxy-8-prenylnaringenin 7-O-${\beta}$-Dglucopyranoside (3) based on the spectroscopic analyses.

• Archives of Pharmacal Research
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• 제14권2호
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• pp.143-146
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• 1991

A new synthetic sequence for the chiral lactone moiety of compactin was developed from $\alpha$-D-glucose in 9 steps via simultaneous reductive detosylation and epoxide-ring opening of 2, 3-epoxy-4-tosylate using NaBH_4$ to afford 2, 4-dideoxy sugar as a key intermediate.