• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.52-56
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• 1991

Inulin degradation was examined using patially puriiied enzyme mixtures of the Exo-inulinase from a Bacillus spp. and the Endo-inulinase from a Pseudomonas spp.. The highest synergistic xtion of the two cnzymcs was observcd when the Exo- and the Endo-inulinase werc mixed at the ratio of 1 to 13, and the rate of hydrolysis of the above process was enhanced approximately 1.6 times I1ight.1- than that of the reaction catalysed with a single enzyme of the same units. The enzymc mixture showed the maximal activity at pH 6.0 and $55^{\circ}C$, and in the prescncc of 0.5 mM each of $CO^{2+}$ and $Mn^{2+}$. Under the optimal condition described above fructosu was accumulated with the overitll concentration of 84% after 36 hours of the reiiction.

• Food Science and Preservation
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• v.5 no.4
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• pp.342-345
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• 1998

This study was investigated to the structure of cell wall during maturation for the research of softening of jujube fruits. Cell was hardly combined with each other untill turning stage, but middle lamella of cell wall was splited at mature stage and was observed splited cell. The middle lamella of cell wall was not observed at green mature stage, but was observed at turning stage. Cell wall was degraded at mature stage. It was observed mitochondria, endoplasmic reticulum et. at in jujube fruit of green mature stage, but cytoplasm and organelle was attached on cell wall as vacuole was grown up after turning stage.

• Journal of Life Science
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• v.22 no.12
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• pp.1724-1728
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• 2012

A marine bacterial strain that degraded fucoidan from Ecklonia cava was isolated from seawater. The crude fucoidanase of this strain efficiently degraded fucoidan at pH 8 and $50^{\circ}C$. The crude enzyme hydrolyzed 7.1% (w/w) fucoidan within 24 hrs from an 1% (w/v) fucoidan solution and produced oligosaccharides by endo-type hydrolysis as the reaction products. The results of 16S rRNA gene sequence analysis and biochemical tests permitted a tentative identification of strain SB 1493 as a Pseudoalteromonas species.

• Korean Journal of Microbiology
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• v.54 no.1
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• pp.46-52
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• 2018

Biodegradation pathway of dibenzofuran (DBF) of Novosphingobium pentaromativorans US6-1, a high-molecular-weight polycyclic aromatic hydrocarbons degrading strain, was investigated via analysis of metabolic intermediates and transcriptome. As a result, 3(2H)-benzofuranone, a basic skeleton of the metabolic intermediates produced by lateral dioxygenation process, was detected as an intermediate. RNA-Seq analysis confirmed that most of the expressed genes upon exposure to DBF were related to the lateral degradation pathway. Based on these results, the biodegradation pathway of DBF by N. pentaromativorans US6-1 was proposed.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.93-97
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• 1991

The enzymatic properties of purified CGTase from alkalophilic Bacillus sp. YC-335 have been examined. Apparent Vmax values of the enzyme in transferring glycosyl residues ${\alpha}-,\;{\beta}-and\;{\gamma}-cyclodextrin(CD)$ to sucrose were $16.13,\;21.8\;and\;9.8{\mu}moles/min/mg\;protein$, respectively and Km values of the corresponding CD were 1.68, 0.33 and 0.37 mM, respectively. A number of saccharides, specially starch hydrolyzates such as glucose and maltose, could activate the dextrinizing activity of the enzym. However, the dextrinizing activity was inhibited by ${\beta}-CD$. It was found from Lineweaver-Burk plot that the inhibition of CGTase by ${\beta}-CD$ was noncompetitive. High performance liquid chromatographic analysis showed that the enzyme has three kinds of activity ; transglycosylation and disproportionation as well as cyclization.

• KSBB Journal
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• v.14 no.6
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• pp.707-712
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• 1999

We have produced new-structured oligosaccharides using mixed-enzyme reactor of dextransucrase from Leuconostoc mesenterides B-512FMCM and ${\alpha}$-amylase. When the concentrations of sucrose and starch were 10%(w/v) and 5%(w/v), respectively, the maximum yield of oligosaccharides with both dextransucrase(100U) and ${\alpha}$-amylase(1000U) was 66.4%. The activity of dextransucrase in mixed-enzyme reactor was increased about 2.5 times by acceptor reaction with starch hydrolyzates. As the activities of dextransucrase:${\alpha}$-amylase were increased from 20U:200U to 500U:5000U, the amount of polymer was increased and the yield of oligosaccharides was decreased. By the addition of sucrose into mixed-enzyme reactor following the prehydrolysis of starch with ${\alpha}$-amylase, the yield was increased up to 12% compared with that of mixed-enzyme reactor without the addition of starch hydrolyzate. New structured-oligosaccharides showed heat resistance up to 140$^{\circ}C$ and was stable in acidic condition at pH 3~6.

• Korean Journal of Microbiology
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• v.26 no.3
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• pp.223-229
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• 1988

Bacillus subtilis K-4-3, which produces considerable amount of $\beta$-glucanase was selected among extracellular $\beta$-glucanase-producing bacteria isolated from soil. $\beta$-glucanase was purified by ammonium sulfate fractionation, Sephadex G-100 gel filtration and DEAE-sephacel ion exchange chromatography. The purified enzyme revealed a single band by polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. Its molecular weight was estimated to be 17000 dalton by SDS-polyacrylamide gel electrophoresis. The optimum pH and temperature of the purified $\beta$-glucanase were 7.0 and $50^{\circ}C$, respectively. The enzyme was strongly inhibited by 1.0mM of $Fe^{3+}$, and activated by 1.0mm of $Li^{}47+$. The absence of glucose after thin layer chromatography of reaction products revealed that the purified enzyme contains no cellobiase or laminarinbiase activity. The loberation of ki, tri-and tetra-saccharide as reaction products can be explained by endoaction of the enzyme.

• Journal of Life Science
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• v.13 no.6
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• pp.970-975
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• 2003

Microbial trichloroethylene (TCE) degradation using trickling biofilter (TBF) is a cost-effective treatment method, in which monooxygenase (MO) fortuitously transforms TCE via cometabolism. Simple TBF, however, could not be stably operated for long-term treatment of TCE due to the contradictory characteristics of cometabolism. In this paper, microbial biocatalyst and biofilm reactor system, a two-stage continuous stirred tank reactor (CSTR)/TBF system using Burkholderia cepacia G4 and Methylosinus trichosporium OB3b, are evaluated for the long-term continuous treatment of TCE. The maximum TCE elimination capacities were in the range of 28 and 525 mg TCE/1$.$day. The reactor systems were stably operated for more than 3∼12 months.

• Korean Journal of Environmental Agriculture
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• v.29 no.4
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• pp.388-395
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• 2010

In order to decrease level of an organophosphorus fungicide, tolclofos-methyl, from in situ ginseng cultivating soil, we isolated a tolclofos-methyl degrading bacteria from ginseng cultivating soil samples. The bacterial strain removed tolclofos-methyl around 95% after 3 days incubation with complete liquid media. The strain was identified as Sphingomonas sp. by 16S rDNA sequence comparison, and designated as Sphingomonas sp. 224. Through the GC-MS analysis, Sphingomonas sp. 224 was proposed to have an initiative degradation pathway generating the metabolite such as 2,6-dichloro-4-methyl phenol compound from tolclofos-methyl. In addition, Sphingomonas sp. 224 was confirmed representing the effective degrading capability to tolclofosmethyl in situ soil.

• Applied Microscopy
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• v.24 no.3
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• pp.67-77
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• 1994

Storage material of endosperm cells digested by various enzymes should be transported to the embryo. At this time, the cellulose of the endosperm cell wall is guessed to be hydrolyzed by the cellulase enabling to transfer the storage material from the endosperm cells to the embryo. Therefore, this study has been carried out to investigate the ultrastructure of endosperm and the localization of the cellase activity on Cannabis sativa L. during germination. Endosperm cells contain a large number of lipid bodies and protein bodies with globoids as the storage material. During gemination they are gradually degenerated, however, the former almost remain until the cells are completely digested. Electron-microscopical reaction products of cellulase on endosperm cells are present. The closer the embryo, the more amount of reaction products on the endosperm cell wall are appeared.