• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.191-195
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• 1993

The intestinal microflora of humans is an extraordinarily complex mixture of microorganisms, the majority of which are anaerobic bacteria. Amongst them, most prevalent bacteria are Bacteroides, Eubacterium, Peptococcus, Bifidobacteria. We isolated a Bacteroides fragilis strain from a Korean adult and examined various glycosidase activities of this strain. The activities of $N-acetyl-{\beta}-glucosaminidase,\;{\alpha}-fucosidase$, ${\beta}-glucuronidase$, chitobiase and PNPCase were stronger in Bacteroides fragilis Roid 8 than in other intestinal anaerobic bacteria. $N-acetyl-{\beta}-glucosaminidase$ was strongest, followed by ${\alpha}-fucosidase$, ${\beta}-glucuronidase$ and PNPCase. The activities of ${\beta}-galactosidase$, ${\beta}-xylosidase,\;{\alpha}-arabinofuranosidase$ were not present or very low. The activities of ${\alpha}-glucosidase$, ${\beta}-glucosidase$ and ${\alpha}-galactosidase$ were present but at a lower level than in Bifidobacterium. The effect of the carbon sources on the production of $N-acetyl-{\beta}-glucosaminidase$, ${\alpha}-fucosidase$, ${\beta}-glucuronidase$ and PNPCase of Bacteroides fragilis Roid 8 was investigated. :.actose and glucose lowered the production of the varous glycosidase enzymes studied in this work. In addition, we investigated the optimum temperature and pH of each glycosidase from Bacteroides fragilis Roid-8 using crude enzyme preparations.

• Journal of Sericultural and Entomological Science
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• v.48 no.1
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• pp.25-27
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• 2006

[ ${\alpha}-Glycosidase$ ] inhibitors slows the velocity of the uptake of monosaccharides in the small intestine by retarding the speed of degradation of disaccharides to monosaccharides, which made it possible to develop ${\alpha}-glycosidase$ inhibitors as the antihyperglycemic ('antihyperglycemic' means 'blood-glucose-level-lowering') reagent for the diabetic patients such as acarbose and miglitol. Twenty kinds of ${\alpha}-glycosidase$ inhibitors have been reported to exist in mulberry, Morns alba, and some of them are also found in the silkworm, Bombyx mari, as the result of its daily feeding of mulberry leaves as the sole diet. 1-Deoxynojirimycin (DNJ), one of the most potent ${\alpha}-glycosidase$ inhibitor, is the most abundant among polyhydroxylated alkaloids with ${\alpha}-glycosidase$ inhibiting activity in both M alba and B. mari, therefore considered the antihyperglycemic criterion of the mulberry- or silkworm-based neutroceutical products. DNJ is thought to be accumulated in the body of silkworm because the its concentration in the silkworm body is two to three times as much as that in the mulberry leaves. Eighteen silkworm F1 varieties have been recommended for industrial rearing in Korea by some standards such as pathological strength. DNJ concentration in 18 recommendedwere measured at 3rd day in the 5th instar after lyophilization to determine the varieties that accumulates DNJ in its body most. GeumOk-Jam was the highest in the DNJ concentration of 5.45 mg/gDW among the recommended F1 varieties.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1397-1401
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• 2005

Bone morphogenetic protein-4 (BMP-4) is a signaling homodimeric molecule that acts as a morphogen to influence cell fate in a concentration-dependent manner. The limited supply of a pure preparation of BMP-4, due to very low level of their expression in vivo, makes it difficult not only to study the biological activities of BMPs, but also to use them as a clinical tool. For a large-scale production of BMP-4, human BMP-4 cDNA was expressed in Chinese hamster ovary (CHO) cells by a recently development vector system, which confers position-independent stable expression of the foreign genes. The CHO cell line expressing recombinant human BMP-4 (rhBMP-4) at the level of $7\;{\mu}g/ml$ could be obtained after stepwise selection with methotrexate. This level of expression is about 70 times higher than those previously reported. The partially processed form of BMP-4 as well as mature form could be detected, when the aliquots of culture media were analyzed by Western blot. The glycosylation pattern and biological activity of the rhBMP-4 were determined by glycosidase treatment and the induction rate of alkaline phosphatase in mouse osteoblastic cells.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.379-382
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• 2018

Trafficking process of viral glycoprotein to cell surface results in the syncytium formation when baby hamster kidney (BHK) cells was infected by Newcastle disease virus (NDV). Rhus chinensis gall, well-known as a medicinal plant, inhibited not only syncytium formation, but also trafficking of glycoprotein, hemagglutinin-neuramidase (HN) to the cell-surface. Modification of viral glycoprotein is processed within the endoplasmic reticulum and golgi body during trafficking into surface. R. chinensis gall extracts showed the strong inhibitory activities ($IC_{50}$ $12.5{\mu}g/mL$) against ${\alpha}-glucosidase$, when compared with the ${\beta}-glucosidase$. And this inhibitory activities is increased by the samples in a dose-depedent pattern. These data showed that the extracts of R. chinensis gall inhibited the cell-surface expression of NDV-hemagglutinin-neuramidase glycoprotein without significantly affecting HN glycoprotein synthesis in NDV-infected BHK cells.