• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.63-63
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• 1993

Phospoinositide-specific phospholipase C (PLC)는 세포막의 phosphoinositide를 분해하여 inositol phosphates와 diacylglycerol을 전달하는데 핵심적인 효소이다. PLC는 분자량과 1차구조의 비교에 의하여 type (PLC-$\beta$, ${\gamma}$, $\delta$)로 구분되며, 각 type마다 2-4종의 subtype이 존재하고 PLC isozyme들에 대한 현재가지의 각종 신호 전달 및 조절에 대한 연구를 종합하면: (1) PLC-$\beta$ type은 G-protein과 연결되어 신호를 전달받고, (2) PLC-${\gamma}$ type은growth factor receptor tyrosine kinase에 의하여 인산화 되어 활성화됨으로, 세포의 성장 신호를 전달하며. (3) PLC-$\delta$ type에 대한 신호 전달이나 조절은 밝혀지지 않고 있다.

• The Korean Journal of Mycology
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• v.31 no.3
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• pp.168-174
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• 2003

In this study, Cordyceps militaris was grown in a liquid medium containing colloidal chitin. A chitinase was purified from the supernatant or cultured medium by ammonium sulfate fractionation, DEAE-Sephadex A-25 and Sephadex G-50 column chromatography. Optimum temperature and pH of this enzyme were $35^{\circ}C$ and 5.5, respectively. The molecular weight of the chitinase was estimated to be 48.5 kDa by SDS-PAGE and its Km value was 0.57 mM. The activity of this enzyme was inhibited by $Cu^{2+},\;Mn^{2+},\;Hg^{2+},\;Zn^{2+},\;CO_{3}^{2-},\;SO_4^{2-},\;CN^-,\;ion,\;and\;OCN^-$ maleic anhydride, acetic anhydride or N-bromo succinimide, especially strongly inhibited by sodium cyanate for 84.0 percentage. But its activity wag slightly stimulated by $Mg^{2+}\;and\;K^+$ ion, respectively. The products formed during hydrolysis of the hexa-N-acetylchitohexaose with this enzyme were N,N'-diacetylchitobiose and N,N',N'-triacetylchitotriose. These results imply that this purified enzyme may be an endo-chitinase.

• Korean Journal of Microbiology
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• v.36 no.2
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• pp.130-135
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• 2000

Decomposition rate of organic matiter in the mud flat of Sunchon Bay was estimated. Physicochemical parameters, cellulose degradation rate. distribution of heterotrophic bacteria, and extracellular enzymatic activities were measured from August 1997 to July 1998. Soil temperatures, water contents, concentration of $PO_4$-P and organic matter were -1-~$30^{\circ}C$, 42.1-53.1%, 0.0779-0.1961 mgig and 1.99-7.64%, respectively. Decomposition rate of cellulose film ranged from 7.7 to 100%imonth, high in summer and low in winter. The number of heterotrophic bacteria ranged from $0.87{\times}10^6 to 3.6{\times}10^7 $CUFsIg dq soil. Enzymatic activities of phosphatase, $\alpha$-D-gluEosidase, $\beta$-D-glucosidase and cellobiohydrolase, which were measured as decomposition rate of methylumbelliferyl(MLiF)-substrate, were 152.23-1779.80 nMIhr, 2.67-202.18 nM/hr, 5.03-258.26 M h r and 3.42-63.07 nM/hr, respectively Cellulose degradaaon rate and extracellular extracellular enzymatic activities were conelated with each other, and showed high correlation coefticiency with soil temperature.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1017-1023
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• 1999

Several extraction conditions of mussel were investigated for preparation of the extract as a natural shellfish seasoning. The conditions studied were extraction temperature and time, addition of sodium phosphates and citrate and hydrolysis with commercial proteolytic enzymes. The extracts were prepared by deshelling, grinding and aqueous extraction followed by centrifugation and filtration. Extraction at $90^{\circ}C$ for 40min showed the highest solids yield with less fishy and high umami taste. Among the several phosphates and citrate added, $Na_{3}PO_{4}$ and $Na_{4}P_{2}O_{7}$ at 1% level were most effective in terms of the yield and umami taste. The pH effects showed that pH 10 resulted the highest solids yield of 28% with less fishy taste. Even though the effect of enzymatic hydrolysis was not greatly different among the commercial enzymes tested, Protamex and Protease II were somewhat better than other enzymes in taste. When the mussel were extracted by the combined conditions, hydrolysis with Protamex followed by extraction at $90^{\circ}C$ for 40min with addition of $Na_{3}PO_{4}$ at pH 10, the solid yields increased up to 30% which was about 58% improvement and high intensity of umami taste and less fishy flavor.

• Microbiology and Biotechnology Letters
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• v.13 no.4
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• pp.355-359
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• 1985

The purified $\beta$-galactosidase from L. sporogenes was most active at pH 7.0 and 6$0^{\circ}C$ with O-nitrophenyl-$\beta$-D-galactopyranoside (ONPG) in 0.05 M phosphate buffer. It was stable over a pH range from 5.0 to 9.0 and lost less than 10％ of its activity after heating for 30 minutes at 6$0^{\circ}C$ and pH 7.0. All the mineral ions examined in this work showed no significant activating effect, whereas L-cysteine exerted a great stimnlatory effect on the enzyme activity at the concentration of 10 mM. The Km values were 1.2 mM for ONPG and 33.3 mM for lactose. Approximately 85％ of lactose in cow's milk, in 10％ skim milk and in 5％ lactose solution was hydrolyzed after 4 hours incubation at 6$0^{\circ}C$ with 2 units of the purified $\beta$-galactosidase per $m\ell$ of the substrate solutions. The $\beta$-galactosidase from L. sporogenes, therefore, is considered to be suitable for hydrolysis of lactose in milk and other dairy products.

• Journal of Oral Medicine and Pain
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• v.32 no.2
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• pp.129-135
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• 2007

Ecdysteroids are known as insect molting hormone. At the same time, ecdysteroids and plant ecdysteroids (phytoecdysteorids) reveal beneficial effects on mammal. The present study was undertaken to determine the possible cellular mechanism of action of phytoecdysteroids in bone metabolism. The effects on the osteoblasts were determined by measuring cell proliferation, alkaline phosphatase (ALP) activity, and gelatinase activity. The effects on the osteoclasts were investigated by measuring tartrate-resistant acid phosphatase (TRAP)(+) multinucleated cells (MNCs) formation after culturing osteoclast precursors. Phytoecdysteroid treatment showed a increase in ALP activity of osteoblasts. Phytoecdysteroid increased the activity of gelatinase. In addition, phytoecdysteroid decreased the osteoclast generation induced by macrophage-colony stimulating factor (M-CSF) and receptor activator of NF-kB ligand (RANKL) in (M-CSF)-dependent bone marrow macrophage (MDBM) cell cultures. Taken these results, phytoecdysteroid may be a regulatory protein within the bone marrow microenvironment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.5
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• pp.664-670
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• 2016

Cheonggukjang (CKJ) is a Korean traditional food made of fermented soybeans. In comparison to normal intake of soybeans, Cheonggukjang has high digestibility with bioactive, antioxidant substances, and thrombolytic enzymes. Recent studies have reported anti-oxidant, anti-cancer, anti-inflammatory, anti-obesity activities as well as inhibitory activities against osteoporosis for CKJ. In this study, we identified the effects of CKJ on osteoblast differentiation by increasing the polyglutamic acid (PGA) content of CKJ. Alkaline phosphatase (ALP) activity and mineralization significantly increased in response to treatment with both natural CKJ (CKJ A) and PGA-increased CKJ (CKJ B). However, CKJ B exhibited higher ALP activity and mineralization than CKJ A. Real-time reverse transcription PCR demonstrated that mRNA expression of osteoblastic-associated genes such as type I collagen, alkaline phosphatase, osteocalcin, and osteopontin in C2C12 cells was significantly up-regulated by CKJ A or B treatment. These results indicate that treatment with CKJ has an anabolic effect on bone by increasing osteoblastic differentiation and ALP activity. Increasing PGA content in CKJ had a greater effect than CKJ A on up-regulation of osteoblastic gene expression in osteoblast cells.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.1
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• pp.79-89
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• 2005

Forest soils were analyzed on their biological and physicochemical properties for the ecological restoration of burnt forest soil using organic wastes and proper microorganisms. Three kinds of soil samples were collected from undamaged soil(US), naturally restoring soil(NS) and artificially restoring soil(AS). All soil samples were sandy soil and acidic soil, ranged pH 5.34~5.78. Moisture content was higher in the soil of NS region. And the others were similar. Total organic matter and soluble sugar were higher at the surface, generally. Heterotrophic soil microbes were abundant at the surface soil of NS and subsoil of AS. Dehydrogenase, cellulase and phosphatase activities were higher at the NS soil. Especially, Dehydrogenase activity as primary index of soil microbial process showed high correlationship with moisture content(r=0.90, P < 0.05).

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.325-331
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• 2002

investigated to maximize the production of fibrinolytic enzyme from Fomitella fraxinea mycelia. Among the tested media, Coriolus versicolor medium (CVM) showed the highest production for the enzyme. 2% galactose, 0.6% yeast extract and 0.1% $NaNO_3$, 0.1% $K_2HPO_4$, and 0.05% $MgSO_4$.$7H_2O$ as carbon, nitrogen, phosphorus, and inorganic salt sources resulted in the maximum level of the enzyme activity, respectively. The enzyme production from F. fraxinea was reached to highest level after the cultivation for 10 days at $25^{\circ}C$ and pH 9. The enzyme activity of culture supernatant was most active at $40^{\circ}C$ and pH 10. The activity of the enzyme was inhibited by phenylmethylsulfonylfluoride and aprotinin, suggesting that it is a serine protease.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.72-75
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• 2007

Using co-immunoprecipitation, we identified proteins interacting with Streptomyces coelicolor RNase ES, an ortholog of Escherichia coli RNase E that plays a major role in RNA decay and processing. Polyphosphate kinase and a homolog of exoribonuclease polynucleotide phosphorylase, guanosine pentaphosphate synthetase I that use inorganic phophate were co-precipitated with RNase E, indicating a possibility of S. coelicolor RNase ES to form a multiprotein complex called degradosome, which has been shown to be formed by RNase E in E. coli. Polynucleotide phophorylase proteins from these two phylogenetically distantly related bacteria species showed similar RNA cleavage action in vitro. These results imply the ability of RNase ES to form a multiprotein complex that has structurally and functionally similar to that of E. coli degradosome.