• BMB Reports
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• 제31권3호
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• pp.269-273
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• 1998

The objective of this study was to evaluate the reversal of multi drug resistance of human cell lines by specific inhibitors of ${\alpha}-glycosidase$ and mannosidases that had been reported to be involved in N-linked oligosaccharide processing of glycoproteins. N-methyldeoxynojirimycin, I-deoxynojirimycin, and castanospermine, which were known to be potent inhibitors of both ${\alpha}-glycosidase$ I and II, showed no activity against the multidrug resistant phenotype of the cell lines of SNU1DOX, KB-V1, and MCF-7/ADR. In contrast, I-deoxymannojirimycin, an inhibitor of mannosidase I, resulted in a slight reversal for the vinblastine resistance of the KB-V1 cell line, but did not show any activity toward the other cell lines. Parallel experiments with tunicamycin, an inhibitor of N-linked glycosylation, also resulted in no significant changes in multidrug resistant (MDR) phenotype of the cell lines tested in this work. These observations suggest that the unglycosylation of P-glycoprotein associated with the inhibitor treatments might not be correlated with the reversal of multidrug resistance of the cell lines tested in this study.

• 한국잠사곤충학회지
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• 제48권1호
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• pp.25-27
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• 2006

누에장려품종 중 혈당강하제 개발에 적합한 품종 결정을 위하여 DNJ 함량을 정량한 결과, 봄에 사육한 금옥잠이 5.45 mg/gDW으로 DNJ 함량이 가장 높았다. 또한 누에 유전자원 원종 66품종의 DNJ 함량을 결정한 결과, 품종간 DNJ 함량 차이가 매우 큰 것으로 밝혀져, 혈당 강하제용 누에 육종시 기초자료가 될 수 있으며, 또한 DNJ 함량이 낮은 품종은 DNJ 축적 기작 연구에 많은 도움이 될 것으로 사료된다.

• Biomolecules & Therapeutics
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• 제6권4호
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• pp.364-370
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• 1998

Glycosidase inhibitors from urine of Bombyx mori were isolated and their inhibitory activities on glycosidases were evaluated. Six compounds were isolated by using several ion exchange columns, and their chemical structures were identified by the physicochemical and spectral data. Compound IV, V and Ⅵ were identified as 1-deoxynojirimycin, fagomine and 1,4-dideoxy-1,4-imino-D-arabinitol, respectively. Among six compounds isolated,1-deoxynojirimycin(IV) was the most potent inhibitor on $\alpha$-glucosidase and $\beta$-galactosidase of rat intestine, and its inhibitory activities for trehalase and almond $\beta$-glucosidase were relatively weak. Compound V and Ⅵl retained a little inhibitory potency toward $\alpha$-glucosidase and $\beta$-galactosidase. Compound II and III, however, have been found to have no effect on all glycosidases tested in this study.

• Biomolecules & Therapeutics
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• 제6권3호
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• pp.242-246
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• 1998

The inhibitory activities of Amberlite active fraction, which was obtained from methanol soluble fraction of freeze dried slikworm urine, on the rat intestinal glycosidase-catalyzed enzymatic reaction were examined in in viro and in vivo experiments. Amberlite active fraction showed significant inhibitory effects on the hydrolysis of o-glycosidic bond, especially $\alpha$-1,4 bond. On the other hand, the inhibition on the hydrolysis of $\beta$-glycosidic bond was very weak. Oral administration of Amberlite active fraction resulted in a dose-dependent decrease in the blood glucose after an oral maltose load, and postprandial hyperglycemia in carbohydrate-loaded mice was suppressed by Amberlite active fraction at 60 mgHg in decreasing order of maltose, starch, sucrose and lactose. 60 mg/kg of Amberlite active fraction lowered the blood glucose level markedly after 18, 35, and 60 min after an oral maltose load and the antihyperglycemic activity was maintained upto 90 min. In alloxan-induced hyperglycemic mice, Amberlite active fraction at a dose of 100 mg/kg also significantly lowered blood glucose after an oral maltose load, and its efficacy was almost equivalent to that of acarbowe.

• Bulletin of the Korean Chemical Society
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• 제18권11호
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• pp.1192-1195
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• 1997

A divergent approach to 2-(hydroxymethyl)pyrrolidine-3,4-diols has been studied with 1,4-dideoxy-1,4-imino-D-arabinitol (D-AB1), a potent glycosidase inhibitor. D-AB1 was efficiently synthesized from 2,3-epoxyalcohol 6a in overall 11% yield.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.115-115
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• 2003

Naturally occurring sugar mimics with a nitrogen in the ring are classified into five structural classes: polyhydroxylated pyrrolidines, piperidines, indolizidines. pyrrolizidine, and nortropanes. Glycosidase are involved in a wide range of important biological processes, such as intestinal digestion, post-translational processing of glycoproteins and the lysosomal catabolism of glycoconjugate. The realization that alkaloidal sugar mimics might have enormous therapeutic potential in many diseases such as viral infection, cancer and diabetes has led to increasing interest and demand for these compounds. Most of these effects can be shown to result from the direct or indrect inhibition of glycosidases.

• Archives of Pharmacal Research
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• 제20권4호
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• pp.346-350
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• 1997

The synthesis of cis- and trans-1,6-dihydroxypyrrolizidine starting from trans-4-hydroxy-L-proline and their evaluation as glycosidase inhibitors are reported. The cis-isomer was found to be a potent inhibitor against .alpha.-glucosidase and showed weak inhibitory effect against other glycosidases. The trans-isomer exhibited weak inhibitions of b-glucosidase and amylo-glucosidase and poor inhibition of other glycosidases.

• 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.134-134
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• 1998

The modulation of glycosidase activity by inhibitors is of great interest. Such compounds have been shown to be important tools in mechanistic studies on glycohydrolase as well as having promising therapeutic application. An ${\alpha}$-glucosidase inhibitor was isolated from culture filterates of Penicillium sp. The inhibitor was active against ${\alpha}$-glucosidase isolated from yeast and porcine small intestine. However, it showed no inhibition to Aspergillus ${\alpha}$-galactosidase, Escherichia coli ${\beta}$-galactosidase, and jack bean ${\alpha}$-mannosidase. The inhibitor was highly soluble in ether, methanol and chloroform. The inhibitor was purified using silica gel, Sephadex LH-20 column chromatography and reverse-phase HPLC. The inhibitory compound designated PA-7(IC$\sub$50/=35$\mu\textrm{g}$) was obtained as white powder. The structure of PA-7 was determined with spectroscopic data of EI-MS, FAB-MS, $^1$H, and $\^$13/C NMR. The inhibitor has a diketopiperazine moiety.

• International Journal of Industrial Entomology and Biomaterials
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• 제7권2호
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• pp.161-164
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• 2003

Several polyhydroxylated alkaloids were isolated from the extracts of freeze-dried silkworm powder, and purified by ion exchange chromatographic analysis. Through the HPLC analysis, we could identify 1-deoxynojirimycin (DNJ) and a kind of calystegin $B_2$ (HS-58) as well as a noble compound (HS-74) from the purified polyhydroxylated alkaloids. In order to know the characteristics of these isolated alkaloids as enzyme inhibitors, glycosidase inhibition activities of these identified alkaloids including other two non-purified alkaloids (SWP 3-1 and SWP 3-2) were investigated.

• 동아시아식생활학회지
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• 제12권5호
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• pp.364-369
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• 2002

본 연구는 천연 자원인 뽕나무에서 혈당강하 효능을 가진 뽕잎(상엽)의 열수 추출법을 이용하여 상엽 추출물의 공정화 확립과 Formulation 개발을 위해 상엽 추출물과 silk peptide 및 한약재를 첨가한 시제품을 동물실험을 통하여 Formulation을 최종 결정하여 제품화하여 기능성 음료를 개발하고자 하였다. 연구 결과, 상엽 추출의 최적 조건은 상엽 크기는 3mm 이하로 하고, 2/3 정도 packing된 면포자루로 포장된 상엽을 사용하며, 상엽 사용량은 50~100 g/L, 추출 온도는 9$0^{\circ}C$, 추출 시간은 2 hr으로 하였으며 이때 수율은 20~25%였다. 또한 시료 배합에 따른 혈당강하 실험을 통하여 상엽 추출물과 silk peptide 의 농도는 각각 1%, 0.1%일 때 혈당강하 작용이 가장 우수하였으며 부재료로 사용된 둥글레는 상엽추출물의 10% 첨가한 경우가 혈당강하작용이 가장 컸으며, polydextrose도 효과가 있으므로 첨가하는 것이 바람직하다고 사료된다.