• YAKHAK HOEJI
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• v.43 no.6
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• pp.818-826
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• 1999

Antidiabetic activity and mechanism of Sangbackpitang (SBPT) was examined in db/db mice, which is a spontaneously hyperglycemic, hyperinsulinemic and obese animal model. SBPT and acarbose were administered orally for 4 weeks. Fasting and non-fasting serum glucose, glycated hemoglobin and triglyceride were all reduced when compared between db/db control group and SBPT treated group. At 12th week after birth, SBPT increased an insulin secretion although statistic significance was not seen. Total activities of sucrase, maltase and lactase in SBPT treated group were all decreased when compared to db/db control. On the other hand, sucrase and maltase activities in acarbose treated groups were increased. Effect of SBPT on mRNA expression of glucose transporter(GLUT-4) was also examined. Quantitation of glucose transporter was performed by RT-PCR and in vitro transcription with co-amplification of rat-action gene as an internal standard. Muscular GLUT-4 mRNA expression in SBPT treated group was increased significantly. These results may suggest that SBPT lowered blood glucose ascribing to inhibition of glycosidase-catalyzed reaction and upregulation of muscular GLUT-4 mRNA expression.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.454-460
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• 2007

Enzymatic properties and substrate specificity of recombinant $\beta-glycosidases$ from a hyperthermophilic archaeon, Sulfolobus shibatae (rSSG), were analyzed. rSSG showed its optimum temperature and pH at $95^{\circ}C$ and pH 5.0, respectively. Thermal inactivation of rSSG showed that its half-life of enzymatic activity at $75^{\circ}C$ was 15 h whereas it drastically decreased to 3.9 min at $95^{\circ}C$. The addition of 10 mM of $MnCl_2$ enhanced the hydrolysis activity of rSSG up to 23% whereas most metal ions did not show any considerable effect. Dithiothreitol (DTT) and 2-mercaptoethanol exhibited significant influence on the increase of the hydrolysis activity of rSSG rSSG apparently preferred laminaribiose $(\beta1\rightarrow3Glc)$, followed by sophorose $(\beta1\rightarrow2Glc)$, gentiobiose $(\beta1\rightarrow6Glc)$, and cellobiose $(\beta1\rightarrow4Glc)$. Various. intermolecular transfer products were formed by rSSG in the lactose reaction, indicating that rSSG prefers lactose as a good acceptor as well as a donor. The strong intermolecular transglycosylation activity of rSSG can be applied in making functional oligosaccharides.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.4
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• pp.433-438
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• 1999

Two components of the neuroendocrine-hormonal response to long-term treatment of acarbose, adipose tissue-derived leptin and central neuropeptide Y (NPY), were investigated in the ICR mice on a high- carbohydrate diet. Acarbose, administered 5 or 50 mg per 100 g diet for four weeks, dose dependently suppressed body weight gain. The body weight gain was reduced along with the amount of daily food intake in 50 mg acarbose-treated group at $7^{th}\;and\;28^{th}$ day. 5 or 50 mg acarbose treatment administered for four weeks reduced leptin mRNA levels to 62% and 77% of the control group, demonstrating that the amount of leptin mRNA in adipocytes correlates with body weight. As dose of acarbose increased, leptin mRNA level also increased, suggesting that potent inhibition of ${\alpha}-glycosidase$ by a higher dose of acarbose furthers the enzyme activity and leptin gene consequently. On the other hand, central expression level of NPY gene was increased significantly compared with the control group at the same amount of acarbose administered, reflecting that leptin and NPY operate in a negative-feedback circuit to regulate body fat stores.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.629-636
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• 2012

Ginsenosides, ginseng saponin, are the principal components responsible for the pharmacological and biological activities of ginseng. In order to improve absorption and biological activities, the biotransformation of major ginsenoside to minor ginsenoside, as the more active compound, is required. In this study, we isolated Lactobacillus brevis THK-D57, which has high ${\beta}$-glycosidase activity, from Kimchi. The major ginsenoside Rb1 was converted to the minor ginsenoside 'compound K' during the fermentation of L. brevis THK-D57. The results propose that the biotransformation pathway to produce compound K is as follows: ginsenoside $Rb_1{\rightarrow}ginsenoside$ $Rd{\rightarrow}ginsenoside$ $F_2{\rightarrow}ginsenoside$ compound K.

• 대한생식의학회:학술대회논문집
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• 2001.06a
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• pp.67-67
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• 2001

• Journal of fish pathology
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• v.27 no.1
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• pp.25-33
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• 2014

Hydrolase activities of excretory-secretory products (ESP) and somatic extracts (SE) from Anisakis simplex sensu stricto (s.s.) and Anisakis pegreffii larvae were investigated by using API ZYM kit. In esterase group, acid phosphatase showed high activity from both of A. simplex (s.s.) and A. pegreffii. Esterase (C4) showed activity only from SE and A. simplex (s.s.) showed higher activity than A. pegreffii. Alkaline phosphatase, acid phosphatase and naphthol-AS-BI-phosphohydrolase showed higher activity in 3rd stage larvae than in 4th stage larvae of both species. In aminopeptidase group, only leucine arylamidase showed remarkable activity in SE of both anisakid species, and A. simplex (s.s.) SE showed higher activity than A. pegreffii SE. In glycosidase group, N-acetyl-${\beta}$-glucosaminidase, ${\alpha}$-mannosidase, ${\alpha}$-fucosidase showed higher activity in A. simplex (s.s.) than A. pegreffii, and 4th larvae showed higher activity than 3rd larvae. These differences in hydrolase activity of anisakid nematodes larvae are thought to be due to different metabolism such as growth, moulting, digestion and feeding.

• Korean Journal of Microbiology
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• v.35 no.3
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• pp.231-236
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• 1999

The fuugus(Penicil1ium oralicum; HCLF-34) secreted the cyanobacteria lytic enzyme which had a molecular weight of about 22 kDa, a optimum temperature of $20^{\circ}C$, a optimum pH of 3.5, and a temperature-stable up to $50^{\circ}C$. The chemical ions such as sodium, potassium, barium, magnesium. and mangan ions appeared positive activity. but calcium, iron, copper ions, EDTA, and PMSF displayed negative activity: this results were the same as the characterilics of other cell wall lytic enzymes. This extracellular enzyme showed lytic aclivily against SDS-insoluble peptidoglycan of Anabaenrr cylinrlrica. The cell wall lylic enzyme of Penicilliurn oxalicum(HCLF-34) seemed to be glycosidase-like enzyme in the fact that ihe concentration of rcducing sugar was increased when the peptidoglycan of Anabaena qlinrlricn md Micrococcus luteus reacted with this enzyme

• Journal of Microbiology and Biotechnology
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• v.9 no.3
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• pp.376-380
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• 1999

Constructs, encoding a single-chain variable fragment of a catalytic antibody 4f4f (scFv-4f4f) with glycosidase activity, were made by combining the coding sequences for the heavy and light chain variable domains with a sequence encoding a linker (GGGGS). Using three different plasmid systems, single-chain antibodies were expressed separately in Escherichia coli, demonstrating significant differences in the expression level and amounts in soluble form of the recombinant protein. The protein expression from pET3a-scFv-4f4f was up to 20% of the total soluble proteins and, more importantly, the proteins were mostly found in a soluble form. An SDS-PAGE analysis of the purified single-chain proteins, yielding higher than 5mg from a 1-1 culture, showed a single band corresponding to its molecular weight of 29,100. A preliminary study shows that the expressed scFv-4f4f is catalytically active. The catalytic parameters for the hydrolysis of p-nitrophenyl-$\beta$-D-glucopyranoside by scFv-4f4f are being investigated.

• Journal of Life Science
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• v.19 no.5
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• pp.680-683
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• 2009

Glycosidase inhibitors are major targets in the treatment of type II diabetes, cancer and viral infections. This study was carried out to investigate the glycosidase inhibitory substances from bamboo (Phyllostachys bambusoides). Bamboo was extracted with methanol and then further fractionated with n-hexane, chloroform, n-BuOH and aqueous to get an active fraction. All extracts were evaluated for ${\alpha}$-glucosidase inhibitory activities to identify the n-hexane fraction with 33.5 ${\mu}$g/ml of IC50 value. Active compound 1 in the n-hexane fraction was identified as linoleic acid, which exhibited inhibitory activity with 12.4 ${\mu}$M of IC50 value. Mechanistic analysis showed that linoleic acid exhibited noncompective inhibition. This is the first study in which bamboo is reported to show ${\alpha}$-glucosidase inhibitory activity.

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.2
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• pp.163-167
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• 2010

[ $\alpha$ ]Glucosidase (EC 3.2.1.20) is a glycosidase that hydrolyzes disaccharides, oligosaccharides, and polysaccharides resulting in the release of α-D-glucose. In this study, $\alpha$-glucosidase activity in the hemolymph and midgut of the mulberry silkworm Bombyx mori and Japanese oak silkmoth Antheraea yamamai was measured using maltose, sucrose, trehalose, and p-nitrophenyl $\alpha$-D-glucopyranoside as substrates. In general, hemolymph $\alpha$-glucosidase activity was higher in B. mori than in A. yamamai. In contrast, midgut $\alpha$-glucosidase activity was higher in A. yamamai than in B. mori for all of the substrates tested. $\alpha$-Glucosidase activity in the midgut of both B. mori and A. yamamai showed similar responses to changes in pH and temperature for all of the substrates tested. Native (7.5%) PAGE of hemolymph and midgut proteins from B. mori and A. yamamai followed by staining with 4-methylumbelliferyl $\alpha$-D-glucoside (MUG) indicated that the $\alpha$-glucosidases of these related lepidopterans are functionally similar but structurally different. In comparison to $\alpha$-glucosidase activity from A. yamamai, $\alpha$-glucosidase activity from B. mori was generally less sensitive to the $\alpha$-glucosidase inhibitors, 1-deoxynojirimycin (DNJ), acarbose, and voglibose when the activity was determined using maltose, sucrose, and trehalose.