• 한국식품영양과학회지
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• 제31권1호
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• pp.131-135
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• 2002

본 연구에서는 작약 추출물의 식후 과혈당 억제작용을 조사하였다. 작약 유기용매(hexane, ethyl acetate, butanol, water) 추출물들을 high performance liquid chromatogrphy를 이용하여 분획한 분획물(fraction)들으 $\alpha$-glucosidase(EC 3.2.1.20) 저해제를 탐색하였다. 작약 ethyl acetate 추출물의 11, 12, 18, 19번 분획물들은 20 $\mu\textrm{g}$/mL에서 각각 85%, 84%, 77%, 77%의 강력한 저해 활성을 나타내었으며, 작약 ethyl acetate 추출물의 10~19번 분획을 경구투여한 in vivo당 (maltose) 부하 실험에서도 양성대조군과 비교하여 유의성 있게 22%의 혈당을 낮추었다. 따라서 본 연구의 in vitro와 in vivo 실험을 통하여 확인 된 $\alpha$-glucosidase 저해 활성을 갖는 작약 분획물들은 식후의 혈당상승 작용을 억제하는 새로운 nutraceutical 소재와 항당뇨 신약개발을 위한 탐색자원으로서 매우 가치있는 자원으로 기대된다.

• 대한한방내과학회지
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• 제30권3호
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• pp.481-494
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• 2009

Background : Radix Sophora Flavescentis (SF) is used for the treatment of diabetes mellitus in Traditional Korean Medicine. However, little is known about the effects of Radix Sophora Flavescentis extract (SFE) on the hypoglycemic mechanism. Objective : We performed a series of experiments to verify the effects of SFE on the proliferation of RIN-m5F, the secretion and synthetic processes of insulin with glucose stimulation and inhibition of $\alpha$-glucosidase. Methods : Various amounts of SFE were added to the RIN-m5F cell culture to identify the effects on the cell proliferation, total amounts of insulin secretion, and related gene expression at the molecular level. Also to identify the inhibitory effect on the $\alpha$-glucosidase activities, ${\rho}NPG$ assay was done with various SFE concentrations followed by comparison with control. Results : SFE did not show considerable effects on RIN-m5F cells proliferation, insulin secretion or insulin mRNA expression, whichever phenomena did not depend on the glucose concentration. However, SFE significantly inhibited $\alpha$-glucosidase activity in a dose dependent manner compared to control. Conclusions : This study showed that SFE has potent $\alpha$-glucosidase inhibitory activity. Thus, SF may by used for the improvement of overall glycemic control. Further mechanism studies on the lipid toxicity and oxidation stress of SF seem to be necessary.

• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.8-13
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• 2002

The isoflavone glycosides are hydrolyzed by ${\beta}$-glucosidase from gut microbes to the bioactive aglycones. However, the specific bacteria from the human intestinal tract that are involved in the metabolism of these compounds are not known. This study was undertaken to develop a fermented soymilk which converts isoflavones to the more bioactive aglycones form using a Bifidobacterium strain. The ${\beta}$-glucosidase activity of 15 Bifidobacterium strains were measured during cell growth. Among them, Bifidobacterium sp. Int-57 was selected for this study, because it has the highest ${\beta}$-glucosidase activity. Growth, acid development, ${\beta}$-glucosidase activity, and the hydrolysis of daidzin and genistin were investigated in four soymilks inoculated with Bifidobacterium sp. Int-57. After 12 h of fermentation, the counts of viable Bifidobacterium sp. Int-57 in all the soymilks reached a level of more than $10^8$ cfu/ml, which was then maintained. The pH of soymilks started to decrease rapidly after 6 h of fermentation and leveled off after 18 h. The titratable acidity of BL# 1 soymilk, BL#2 soymilk, and JP#l soymilk increased from 0.18 to 1.21, 1.15, and $1.08\%$ over the fermentation period, respectively. After 24 h of fermentation, the $\beta$-glucosidase activity in BL#1 soymilk, BL#2 soymilk, JP#l soymilk, and JP#2 soymilk increased to 59.528, 40.643, 70.844, and 56.962 mU/ml, respectively. The isoflavone glycosides, daidzin and genistin, in soymilks were hydrolyzed completely in the relatively short fermentation time of 18 h. These results show that Bifidobacterium sp. Int-57 can be used as a potential starter culture for developing fermented soymilk which has completely hydrolyzed isoflavone glycosides.

• Journal of Microbiology and Biotechnology
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• 제23권11호
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• pp.1577-1585
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• 2013

Bioethanol production from lignocellulose is considered as a sustainable biofuel supply. However, the low cellulose hydrolysis efficiency limits the cellulosic ethanol production. The cellulase is strongly inhibited by the major end product cellobiose, which can be relieved by the addition of ${\beta}$-glucosidase. In this study, three ${\beta}$-glucosidases from different organisms were respectively expressed in Saccharomyces cerevisiae and the ${\beta}$-glucosidase from Saccharomycopsis fibuligera showed the best activity (5.2 U/ml). The recombinant strain with S. fibuligera ${\beta}$-glucosidase could metabolize cellobiose with a specific growth rate similar to the control strain in glucose. This recombinant strain showed higher hydrolysis efficiency in the cellulose simultaneous saccharification and fermentation, when using the Trichoderma reesei cellulase, which is short of the ${\beta}$-glucosidase activity. The final ethanol concentration was 110% (using Avicel) and 89% (using acid-pretreated corncob) higher than the control strain. These results demonstrated the effect of ${\beta}$-glucosidase secretion in the recombinant S. cerevisiae for enhancing cellulosic ethanol conversion.

• 생약학회지
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• 제40권3호
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• pp.229-232
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• 2009

The ethanol (EtOH) extract of the branches of Cotinus coggygria (Anacardiaceae) exhibited a significant inhibition on the yeast $\alpha$-glucosidase, one of the key enzymes related with diabetes mellitus, in a dose dependent manner, in vitro. The intensive phytochemical survey of the EtOH extract of the species by way of bioactivity-guided fractionation resulted in the isolation of 1,2,3,4,6-penta-O-galloyl-$\beta$-D-glucose (1) as an active principle responsible for the inhibition on $\alpha$-glucosidase, together with two related components 2 and 3. Compound 1 demonstrated a strong inhibition on the yeast $\alpha$-glucosidase, in vitro and $IC_{50}$ value was calculated as 0.96 mg/ml, when that of a reference drug, acarbose was estimated as 5.3 mg/ml. On the other hand, other related constituents of the species, 1,2,3,6-tetra-O-galloyl-$\beta$-D-glucose (2) and gallic acid (3) were exhibited relatively poor inhibition upon the yeast $\alpha$-glucosidase, respectively.

• Journal of Microbiology and Biotechnology
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• 제25권1호
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• pp.57-65
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• 2015

β-Glucosidase production by the white rot fungus Flammulina velutipes CFK 3111 was evaluated using different carbon and nitrogen sources under submerged fermentation. Maximal extracellular enzyme production was 1.6 U/ml, corresponding to a culture grown in sucrose 40 g/land asparagine 10 g/l. High production yield was also obtained with glucose 10 g/land asparagine 4 g/l medium (0.5 U/ml). Parameters affecting the enzyme activity were studied using p-nitrophenyl-β-_D-glucopyranoside as the substrate. Optimal activity was found at 50℃ and pHs 5.0 to 6.0. Under these conditions, β-glucosidase retained 25% of its initial activity after 12 h of incubation and exhibited a half-life of 5 h. The addition of MgCl₂, urea, and ethanol enhanced the β-glucosidase activity up to 47%, whereas FeCl₂, CuSO₄, Cd(NO₃)₂, and cetyltrimethylammonium bromide inflicted a strong inhibitory effect. Glucose and cellobiose also showed an inhibitory effect on the β-glucosidase activity in a concentration-dependent manner. The enzyme had an estimated molecular mass of 75 kDa. To the best of our knowledge, F. velutipes CFK 3111 β-glucosidase production is amongst the highest reported to date, in a basidiomycetous fungus.

• 생약학회지
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• 제47권1호
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• pp.29-37
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• 2016

Anti-diabetic potential of the leaves of A. elata through the inhibitory activity on PTP1B and ${\alpha}$-glucosidase has not been reported. In this study, the EtOAc fraction of methanolic extract from the leaves of A. elata showed potent inhibitory activity against the PTP1B and ${\alpha}$-glucosidase with $IC_{50}$ value of $96.29{\pm}0.3$ and $264.71{\pm}14.87{\mu}g/mL$, respectively. Three known triterpenoids, oleanolic acid, oleanolic acid-28-O-${\beta}$-D-glucopyranoside and oleanolic acid-3-O-${\beta}$-D-glucopyranoside were isolated from the most active EtOAc fraction. We determined the chemical structure of these triterpenoids through comparisons of published nuclear magnetic resonance (NMR) spectroscopic data. Furthermore, we screened these triterpenoids for their ability to inhibit PTP1B and ${\alpha}$-glucosidase over a range of concentrations ($12.5-50{\mu}M$). All three terpenoids significantly inhibited PTP1B in a concentration dependent manner and oleanolic acid effectively inhibited ${\alpha}$-glucosidase. In addition, these compounds revealed potent inhibitory activity with negative binding energies toward PTP1B, showing high affinity and tight binding capacity in the molecular docking studies. Therefore, the results of the present study clearly demonstrate that A. elata leaves and its triterpenoid constituents might be beneficial in the prevention or treatment of diabetic disease.

• 생약학회지
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• 제40권2호
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• pp.150-154
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• 2009

We examined ethanol extracts prepared from the Korean marine algae belonging to the Sargassaceae family for their inhibitory effects on ${\alpha}$-glucosidase activity and free radicals in vitro. Among five marine algae, the extracts of Sargassum yezoense were found to possess strongly ${\alpha}$-glucosidase inhibition and free radicals scavenging activities. Two compounds were isolated via bioactivity guided isolation and tested for their effects on ${\alpha}$-glucosidase, DPPH, $ABTS^{+}$ and $Photochem^{(R)}$ analysis. Their chemical structures were elucidated by spectral analysis and direct comparison with authentic compounds; their structures were identified as sargaquinoic acid (1) and sargahydroquinoic acid (2). The inhibitory effects of compound 1 and 2 ($IC_{50}$ value:14.2 and 12.8 ${\mu}M$, respectively) on ${\alpha}$-glucosidase were more potent that of deoxynojirimycin as a positive control ($IC_{50}$ value:18.0 ${\mu}M$). All compounds displayed antioxidative activity which was measured by DPPH, $ABTS^{+}$ and $Photochem^{(R)}$ apparatus.

• 미생물학회지
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• 제35권1호
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• pp.35-40
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• 1999

소양호에서 식물 플랑크톤이 분비하는 유기물의 분자량 크이게 따른 세균수와 활성의 변화를 측정하였다. 소양호 상걸리 유역에서 여름철에 채수한 물을 tangential flow ultrafiltration 으로 용존 유기물질을 100,000 nMW~0.1$\mu\textrm{m}$, 10,000 nMW~100,000 nMW와 1,000 nMW~10000 nMW의 3개 fraction으로 구분하였고, 여기에 호숫물을 접종하여, 세균수와 $\beta$-glucosidase 의 변화를 측정하였다. 배양기간 동안에 나타난 총세균수는 24시간까지 급격히 증가한 후 점차 안정적으로 변하는 전형적인 성장곡선을 나타내었으며, DOC 농도와 종류가 달랐음에도 , $1.2{\times}10^{7}$ cells $ml^(-1)$범위였고, 저분자 fraction에 비해 최고 1,000배 이상 높았다. 즉 10,000 nMW 이상의 고분자 용존 유기물질은 $\beta$-glucosidase의 유도체로 작용하며, 저분자 용존 유기물질은 $\beta$-glucosidase 활성도를 높이지 못하는 것으로 확인되었다.

• 약학회지
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• 제55권6호
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• pp.446-450
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• 2011

As an effort to find a new scaffold for ${\alpha}$-glucosidase inhibition, we have prepared total 11 phenylalkylated piperazine derivatives and tested their ${\alpha}$-glucosidase inhibitory activities. Compounds 8 ($IC_{50}=2.73{\pm}0.075mM$) possessing two 3-methoxyphenethyl group on 1,4-position of piperazine showed comparable potency to acarbose used as reference. But other compounds were inactive to ${\alpha}$-glucosidase. The result indicated that proper substituents on the piperazine can engender ${\alpha}$-glucosidase inhibitory activities on the piperazine derivatives.