• Journal of Applied Biological Chemistry
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• v.60 no.3
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• pp.257-263
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• 2017

A cellulolytic strain Y2 was isolated from soil obtained in the Canadian Alpine region. The isolate was identified as Paenibacillus sp. Y2 by 16S rRNA sequencing. When grown in LB medium supplemented with carboxymethyl-cellulose (CMC), CMCase production increased to 122.0% of that observed in LB without CMC. Culture supernatant was concentrated by ultrafiltration and 80% ammonium sulfate precipitates were separated by Hi-Trap Q and CHT-II chromatography. The purified enzyme (EG-PY2) showed a homogeneous single band and the molecular mass was estimated to be 38 kDa by SDS-PAGE. Optimum pH and temperature of the enzyme were 4.5 and $30^{\circ}C$, respectively. The half-life of enzyme activity at 50 was 140.7 min, but the enzyme was drastically inactivated within 5 min at $55^{\circ}C$. The enzyme was highly activated to 135.7 and 126.7% by 5.0 mM of $Cu^{2+}$ or $Mg^{2+}$ ions, respectively, and moderately activated by $Ba^{2+}$ and $Ca^{2+}$ ions, whereas it was inhibited to 76.8% by $Fe^{2+}$, and to ${\leq}50%$ by $Mn^{2+}$, $Co^{2+}$, $Zn^{2+}$, and EDTA. The enzyme was activated to 211.5% in the presence of 0.5 M of NaCl and greatly tolerant to 3.15M of NaCl. The enzyme showed 2.98 times higher ${\beta}$-glucanase activity than CMCase activity. Based on these results, it can be concluded that EG-PY2 is an acidophilic, cold-active, and halotolerant endoglucanase. The authors suggest it is considered to be useful for various industrial applications, such as, fruit juice clarification, acidic deinking processes, high-salt food processing, textile and pulp industries, and for biofuel production from seaweeds.

• Korean Journal of Materials Research
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• v.23 no.5
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• pp.271-275
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• 2013

Cobalt (Co) compounds have been used for centuries to impart rich blue color to glass, glazes and ceramics. Cobalt monoxide (CoO), an oxide of Co, is an inorganic compound that has long been used as a coloring agent in the ceramic industry. Unlike other coloring agents, CoO can be used to develop colors other than blue, and several factors such as its concentration in the glaze and firing condition have been suggested as possible mechanisms. For example, CoO produces a typical blue color called "cobalt blue" at very low concentrations such as 1 wt% in both oxidation and reduction firing conditions; a higher concentration of CoO (5 wt%) develops a darker blue color under the same firing conditions. Interestingly, CoO also develops a purple color at high concentrations above 10 wt%. In this study, we examined the applicability and mechanism of a novel purple glaze containing cobalt(II, III) oxide, one of the well characterized cobalt oxides. Experimental results show that an Augite crystal isoform (Augite-Fe/Co) in which Fe was replaced with Co is the main component contributing to the formation of the purple color. Based on these results, we developed a glaze using chemically synthesized Augite-Fe/Co crystal as a color pigment. Purple color glaze was successfully developed by the addition of 6~15 wt% of $Co_3O_4$ to magnesia lime.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.3
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• pp.15-32
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• 2011

This study was carried out to investigate the soil characteristics and propose the management for the Monument Beobsoo Marsh, Korea. The soil properties of O.M, $Ca^{2+}$, $Na^+$ and CEC were higher and the soil properties of pH_{1:5}$ and $P_2O_5$ were lower the studied sites than other marsh sites in Korea. Although the Heavy metals such as Pb, Hg, Cd, Cu, Zn, Cr and As were lower compare to the safety standard of soil pollution in Korea, the overall conservation management plan based on long-term monitoring should be considered just because it varied by the point and non-point source pollution within the studied marsh. The source of water pollution varied due to non-point polluting origins such as sewage inlet, degraded terrain for agriculture, fishing sites, sites of removed water grasses, pesticides, chemical fertilizers, as well as fallen leaves. The creation of an artificial marsh is recommended due to the soil environment of the studied sites may be changed owing to the accumulated contaminants from the sources of both of point or non-point contaminants. The establishment of the zones of core, buffer and transition which is basic management structure of the UNESCO MaB could be applied to manage the studied site. Simultaneously the promotion of voluntary participation and education of the local residents are needed.

• Food Science and Preservation
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• v.19 no.5
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• pp.619-625
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• 2012

In the present study, the proximate composition, sugar, minerals, total phenolic and flavonoid compounds, and amino acids in Calystegia japonica (C. japonica) were measured to determine if it can be used as a nutritional and functional material for the development of valuable foods. The mean crude protein, fat, and ash contents of the leaves were 5.75, 2.46, and 7.77%, respectively. The soluble-protein contents of the leaves and roots were 146.78 and 33.67 mg%, respectively. The reducing-sugar and free-sugar contents of the leaves were 682.70 and 166.00 mg%, respectively, and those of the roots were 2,934.89 and 37.70 mg%. The mineral content of the leaves was 3,122.13 mg%, and that of the roots was 1,540.85 mg%. The three elements Ca, K, and Mg were very rich in all their parts, with minerals accounting for 96-99% of their total mineral contents. The total phenolic compound of the leaves was 3,028.89 mg%, and the total flavonoid compound was 382.67 mg%. The phenolic and flavonoid compounds in the leaves were more than 7.6 times those in the roots. The free-amino acid levels in the leaves and roots were 2,467.15 and 1,334.81 mg%, respectively. The results of the comparison of the leaves and roots of C. japonica showed that the leaves had a rich proximate composition consisting of minerals, total phenolic and flavonoid compounds, and amino acid. This suggests that C. japonica leaves are potentially useful sources of functional and favorite foods and nutraceuticals.

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.456-463
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• 1991

$\beta$-Galactosidase of Bifidobacterium longum KCTC 3215 was studied on the production, purification, and characterization. Optimum conditions for the enzyme production were in the medium of 1.0% lactose as carbon source, initial pH 7.0 and in 17 hours of cultivation at $37^{\circ}C$. The enzyme was purified 9.25 folds by protamine sulfate precipitation, ammonium sulfate fractionation, DEAE-Sephadex A-50 ion exchange chromatography and Sephadex G-150 gel filtration. The maximal P-galactosidase activity was observed at pH 6.5 and at the temperature of $40^{\circ}C$ This enzyme was stable at pH 6.0-8.5. Metal ions such as $Ca^{2+} \;and \; Co^{2+}$, 2-mercaptoethanol, cysteine, and glutathione stimulated B-galactosidase activity. The enzyme activity was inhibited by addition of $Mg^{2+}, Fe^{2+}, Cs^{1+}, Li^{1+}$, DETA, galactose, and $\rho$-chloromercuribenzoic acid. The kinetics of o-nitrophenyl-$\beta$-D-galactopyranoside and lactose were $K_m$ = 1.66 mM, $V_{max}= 0.30 mM/min\cdot mg\cdot protein$ and $KK_m = 3.18 mM, \; V_{max}= 0.42 mM/min \cdot mg\cdot$ protein, respectively. The molecular weight of native enzyme was about 360, 000 dalton and the enzyme consisted of 2 identical subunits with a molecular weight of 180, 000.

• Journal of Microbiology and Biotechnology
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• v.21 no.3
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• pp.236-242
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• 2011

A psychrotrophic bacterium, Arthrobacter sp. ON14, isolated from Antarctica, was shown to exhibit a high ${\beta}$-galactosidase activity at a low temperature. A genomic library of ON14 was constructed and screened for ${\beta}$-galactosidase genes on functional plates containing 5-bromo-4-chloro-3-indolyl-${\beta}$-D-galactopyranoside (X-gal) as the substrate. Two different ${\beta}$-galactosidase genes, named as galA, galB, were found in ON14. Computational analyses of the genes revealed that the encoded protein GalA belongs to family 2 of glycosyl hydrolysases and is a cold-active protein, whereas GalB belongs to family 42 of glycosyl hydrolysases and is a mesophilic protein. Reverse transcription analyses revealed that the expression of galA is highly induced at a low temperature ($4^{\circ}C$ ) and repressed at a high temperature ($28^{\circ}C$ ) when lactose is used as the sole carbon source. Conversely, the expression of galB is inhibited at a low temperature and induced at a high temperature. The purified GalA showed its peak activity at $15^{\circ}C$ and pH 8. The mineral ions $Na^+$, $K^+$, $Mg^{2+}$, and $Mn^{2+}$ were identified as enzyme activators, whereas $Ca^{2+}$ had no influence on the enzyme activity. An enzyme stability assay revealed that the activity of GalA is significantly decreased when it is incubated at $45^{\circ}C$ for 2 h, and all its activity is lost when it is incubated at $50^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.19-25
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• 2014

An extracellular agarase was purified from Bacillus sp. BI-3, a thermophilic agar-degrading bacterium isolated from a hot spring in Indonesia. The purified agarase revealed a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with an apparent molecular mass of 58 kDa. The optimum pH and temperature of the agarase were 6.4 and $70^{\circ}C$, respectively. The activity of the agarase was stable at high temperatures, and more than 50% activity was retained at $80^{\circ}C$ for 15 min. Furthermore, the enzyme was stable in the pH range of 5.8-8.0, and more than 60% of the residual activity was retained. Significant activation of the agarase was observed in the presence of $K^+$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$, and $Sr^{2+}$; on the other hand, $Ba^{2+}$, $Zn^{2+}$, $Cu^{2+}$, $Mn^{2+}$, $Co^{2+}$, $Fe^{2+}$, and EDTA inhibited or inactivated the enzyme activity. The components of the hydrolytic product analyzed by thin-layer chromatography showed that the agarase mainly produced neoagarobiose. This study is the first to present evidence of agarolytic activity in aerobic thermophilic bacteria.

• Korean Journal of Veterinary Service
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• v.34 no.3
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• pp.217-226
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• 2011

Salmonella spp. is of increasing public health concern as causative pathogens of food poisoning. The aim of this study was to investigate the serotypes and antimicrobial resistance pattern of Salmonella spp. isolated from duck farms in Daegu-Gyeongbuk province. Also, S. Enteritidis and S. Typhimurium isolates were further examined for plasmid analysis, phage typing and pulsed-field gel electrophoresis (PFGE). A total of 34 Salmonella spp. (16.4%) were isolated from duck farms and ten serotypes were identified. The predominant serotypes were S. Typhimurium (23.5%) S. Fyris (17.6%) and S. Haardt (11.8%), S. Agona and S. Enteritidis (respectively 8.8%). Of 34 Salmonella isolates, 15 (44.1%) isolates were resistant to at least one antimicrobial agent and multiple resistance (resistance to more than 4 drugs) was observed in 9 strains (26.5%). The high resistance was found to streptomycin (32.4%), tetracycline (29.4%), ampicillin, kanamycin and nalidixic acid (respectively, 26.5%), all Salmonella isolates were susceptible to cefoxitin, cefotaxime, gentamicin, amikacin and ciprofloxacin. All S. Enteritidis and S. Typhimurium isolates were found to contain only one plasmid (ca. 54 or 55kb, respectively). Among the S. Enteritidis isolates, two phage types were found, PT32a and PT1c, respectively, one isolates did not react with any of the phages used. Whereas, all S. Typhimurium isolates were RDNC (reacts but does not conform). PFGE showed to be a useful typing method better than plasmid analysis and phage typing for discrimination of isolates especially, S. Typhimurium isolates. Our results indicated that the serotypes of Salmonella isolates are widely distributed in duck farms, further epidemiological studies should be carried out.

• Journal of Technologic Dentistry
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• v.42 no.3
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• pp.234-239
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• 2020

Purpose: We investigated the marginal fit between abutment and metal copings according to impression technique, wax block types, and metal types. Methods: We selected the traditional impression method of using rubber impression materials and the digital impression method of using oral scanners, three types of wax blocks, and two types of metal, both of which were domestically and commercially available, were selected to produce metal copings, and the marginal fit was determined through the use of silicon replication. Results: The measurements of axial wall fit revealed that the IYV specimens had the best fit, with a mean gap of 24.11±5.95 ㎛, followed by CEV, CHV, CSS, CSV, CES, CHS, and IYS specimens (mean: 33.44±8.41 ㎛). The differences were not statistically significant. The marginal gap measurements showed that the CEV specimen had the smallest gap, 17.25±4.13 ㎛, followed by the CSV, CHV, CSS, CES, CHS, IYV, and IYS specimen (mean: 43.47±15.63 ㎛). The differences were statistically significant. Conclusion: The axial wall fit of the metal coping (VeraBond2V; Aalba Dent, Inc., Fairfield, CA, USA) produced by the lost wax technique with the traditional impression method was excellent. The marginal fit of the metal coping (VeraBond 2V) produced by wax milling with the use of an oral scanner was also excellent. The marginal fit of the metal coping was within the clinically acceptable limits in all groups.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.53-60
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• 2004

Recently, there has been a growing tendency to use whole crop rice for feeds as there is an increased rice supply and a decrease in the demand for rice in Korea. Little information, however, is available about the management and utilization of whole crop rice for feeds. This study was conducted to decide the optimum harvest date through examining the plant height, dry matter(DM) yield and feed composition of whole crop rice harvested at different maturity. Field study was established early in May until October 7th on a rice field at Yupori, Sinbuk-yeup, Chunchon, Kangwon-Do. "Ilpum" mutant rice was sown at 52 kg/ha, and N, P and K were applied at 209, 113 and 81 kg/ha, respectively. The rice was harvested at six different mature stages for analysis; booting stage; 17 Aug., milk-ripe stage; 27 Aug., dough stage; 7 Sep., yellow ripe stage; 17 Sep., dead ripe stage; 27 Sep. and full ripe stage; 7 Oct. Plant height was 77 cm in booting stage (P<0.05) which was lower when compared to the other stages among which the heights did not differ with average range of 93∼97 cm. The highest dry matter yield was observed in yellow ripe stage (22.8 T/ha), which was followed by dead ripe stage (19.3 T/ha), full ripe stage (19.3 T/ha), and dough stage (15.1 T/ha). Crude protein (CP) and Neutral detergent fiber (NDF) concentrations consistently decreased with maturity. The highest concentrations of CP and NDF were obtained in booting stage with 9 and 73.6%, respectively (P<0.05), and lowest in full ripe stage with 5.8 and 64.6%, respectively (P<0.05). The concentration of total digestible nutrient (TDN) was highest in booting stage (59.7%); however no significant difference was found among other stages. The concentrations of Ca and P were not different among mature stages. According to these results, the yellow ripe period is appropriate to harvest the whole crop rice for forage considering dry matter yields, feed compositions and TDN concentrations.