• Food Science of Animal Resources
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• v.23 no.3
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• pp.278-283
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• 2003

Feasibility tests on using liposomes for detecting food-borne pathogenic bacteria were studied with E. coli 0157:H7 as a model analyte. lmmunoliposomes, whose surface was conjugated with anti-E. coli 0157:H7 IgG and which encapsulated the marker dye, sulforhodamine B, were used for the detection label. Among the feasibility tests, the first test was to use a test-strip on which antibodies to anti-E. coli O157:H7 IgG were immobilized. In this format, immunoliposomes that did not bind to E. coli O157:H7 in sample were captured and then exhibited a visible signal which was inversely related with the number of E. coli O157:H7 in sample. The second test was a direct liposome assay followed by immunomagnetic separation. In this format, immunoliposomes which were bound to E. coli O157:H7 were lysed with detergent and produced a signal which was proportionally related with the number of E. coli O157:H7 in sample. The results from both formats indicate that liposomes can be utilized as a detection label.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.1
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• pp.47-52
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• 1989

Aspergillus awamori, B-2 which has a high ability to decolorize melanoidin was selected among various fungi. Aspergillus awamori, B-2 showed the highest decolorization activity when it was cultivated in a melanoidin medium containing 3.0% glucose, 0.5% yeast extract, 0.1 % $KH_2PO_4\;and\;0.05%\;MgSO_4{\cdot}7H_2O$ at an initial pH 7.0 at $37^{\circ}C$ for 5 days. Mycelia immobilized system with. Ca-alginate was more effective on melanoidin decolorization activity showed approximately 70% in 10 days under the optimal conditions. Continuous decolorization of melanoidin using, reuse of immobilized mycelia showed an almost constant decolorization of abort 60-70% for 15 days.

• Food Science of Animal Resources
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• v.30 no.6
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• pp.946-950
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• 2010

This study evaluated the antimicrobial effects of meat processing-related organic acids on Burkholderia thailandensis (Burkholderia pseudomallei surrogate) with different water activities. B. thailandensis KACC12027 (4 log CFU/mL) was inoculated in microwell plates containing tryptic soy broth pH-adjusted to 4, 5, 6, and 7 with ascorbic acid, citric acid, and lactic acid and with water activities adjusted to 0.94, 0.96, 0.98, and 1.0 with NaCl, followed by incubation at $35^{\circ}C$ for 30 h. The optical density (OD) of the samples was measured at 0, 3, 6, 12, 24, and 30 h at 595 nm to estimate the growth of B. thailandensis. Growth of B. thailandensis was observed only at water activity of 1.0. In general, more bacterial growth (p<0.05) was observed at pH 6 than at pH 7, and the antimicrobial effects of the organic acids on B. thailandensis were in the following order: Ascorbic acid > lactic acid > citric acid after incubation at $35^{\circ}C$ for 30 h. These results indicate that organic acids in meat processing-related formulations should be useful in decreasing the risk related to an emerging high risk agent (B. pseudomallei).

• Journal of the Korean Vacuum Society
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• v.10 no.1
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• pp.104-111
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• 2001

B-doped hydrogenated amorphous silicon carbide (a-SiC:H) thin films were prepared by plasma-enhanced chemical-vapor deposition in a gas mixture of $SiH_4, CH_4,\;and\; B_2H_6$. Physical and chemical properties of a-SiC:H films grown with varing the ratio of $B_2H_6/(SiH_4+CH_4)$ were characterized with various analysis methods including scanning electron microscopy (SEM), X-ray diffractometry (XRD), Raman spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, secondary ion mass spectroscopy (SIMS), UV absorption CH_4spectroscopy and electrical conductivity measurements. With the B-doping concentration, the doping efficiency and the micro-crystallinity were decreased and the film became amorphous when $B_2H_6/(SiH_4{plus}CH_4)$ was over $5{\times}10^{-3}$. The addition of $B_2H_6$ gas during deposition decreased the H content in the film by lowering the quantity of Si-C-H bonds. Consequently, the optical band gap and the activation energy of a-SiC:H films were decreased with increasing the B-doping level.

• Korean journal of food and cookery science
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• v.21 no.5
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• pp.575-584
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• 2005

The objective of this study was to develop bioactive ginseng yogurt, fermented by B. minimum KK-1 and B. cholerium KK-2, which showed transforming activity of ginseng extract to compound K. Among older people, 3% ginseng yogurt fermented by B. minimum KK-1 and mixed with Bifidobacterium KK-1, KK-2 showed the highest overall acceptability(6.80, 6.80) among 1%(3.87, 3.67), 2%(4.40, 4.53) and 3% ginseng yogurt. The pH of ginseng yogurt was lower than that of plain yogurt. During 9 days of storage, the pH of each yogurt slightly decreased and then increased until 15 days of storage. The 3 8.25 log CFU/g and B. cholerium KK-2; 7.78 log CFU/g). Therefore, ginseng might be used as a growth factor during the fermentation of yogurt. The L value of ginseng yogurt decreased, and the a and b values increased, with increasing ginseng concentration.

• Bulletin of the Korean Chemical Society
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• v.14 no.1
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• pp.101-107
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• 1993

Ab initio calculations are carried out at the 6-311G$^{**}$ level for the $C_{2v}$ interactions of Be and Li atoms with acetylene molecule. The main contribution to the deep minima on the $^3B_2\;BeC_2H_2\;and\;^2B_2 LiC_2H_2$ potential energy curves is the b_2\;(2p(3b_2)-l{\pi}_g^*(4b_2))$ interaction, the $a_1\;(2s(6a_1)-I{\pi}_u(5a_1))$ interaction playing a relatively minor role. The exo deflection of the C-H bonds is basically favored, as in the $b_2$ interaction, due to steric crowding between the metal and H atoms, but the strong in-phase orbital interaction, or mixing, of the $a_1$ symmetry hydrogen orbital with the $5a'_1,\;6a'_1,\;and\;7a'_1$ orbitals can cause a small endo deflection in the repulsive complexes. The Be complex is more stable than the Li complex due to the double occupancy of the 2s orbital in Be. The stability and structure of the $MC_2H_2$ complexes are in general determined by the occupancy of the singly occupied frontier orbitals.

• Korean Journal of Crystallography
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• v.15 no.2
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• pp.99-103
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• 2004

The structure of $C_{16}H_{19}O_2N_3CuCl_2\;{\cdot}\;H_2O$ has been determined by X-ray diffraction methods. The crystal system is triclinic, space group Pl, unit cell constants. $a=7.6202(9)\; \AA,\; b=8.5943(7) \AA,\; c= 8.6272(6) \AA,\; \alpha= 67.518(6)^{\circ}.\; \beta= 68.043(8)^{\circ},\; \gamma=74.370(8)^{\circ},\; V=478.89(8)\; \AA^3,\; T=295K,\; Z=1,\; D_c=1.504Mgm^{-3}$The intensity data were collected on an Enraf-Nonius CAD-4 Diffractometer with graphite monochromated $MoK\alpha$ radiation $(\alpha=0.7107\;\AA)$. The molecular structure was solved by direct method.』 and refined by full-matrix least squares to a final $R=2.47\%$ for 1659 unique observed $F_0>4\sigma(F_0)$ reflections and 234 parameters.

• Journal of the Korean Magnetics Society
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• v.15 no.6
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• pp.315-319
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• 2005

To obtain low switching field ($H_{SW}$) we introduced amorphous ferromagnetic $Co_{70.5}Fe_{4,5}Si_{15}B_{10}$ single and synthetic antiferromagnet (SAF) free layers in magnetic tunnel junctions (MTJs). The switching characteristics for MTJs with structures $Si/SiO_2/Ta$ 45/Ru 9.5/IrMn 10/CoFe 7/AlOx/CoFeSiB 7 or CoFeSiB (t)/Ru 1.0/CoFeSiB (7-t)/Ru 60 (in nm) were investigated and compared to MTJs with $Co_{75}Fe_{25}$ and $Ni_{80}Fe_{20}$ free layers. CoFeSiB showed a lower saturation magnetization of $560 emu/cm^3$ and a higher anisotropy constant of $2800\;erg/cm^3$ than CoFe and NiFe, respectively. An exchange coupling energy ($J_{ex}$) of $-0.003erg/cm^2$ was observed by inserting a 1.0 nm Ru layer in between CoFeSiB layers. In the CoFeSiB single and SAF free layer MTJs, it was frond that the size dependence of the $H_{SW}$ originated from the lower $J_{ex}$ experimentally and by micromagnetic simulation based on the Landau-Lisfschitz-Gilbert equation. The CoFeSiB SAF structures showed lower $H_{SW}$ than that of NiFe, CoFe and CoFeSiB single structures. The CoFeSiB SAF structures were proved to be beneficial far the switching characteristics such as reducing the coercivity and increasing the sensitivity in micrometer to submicrometer-sized elements.

• Journal of the Korean Chemical Society
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• v.53 no.1
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• pp.90-94
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• 2009

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1051-1054
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• 2004

The structural transformation behavior of $Na_2Ti_3O_7$ by hydrolysis was investigated in mild and strong acidic aqueous medium. Compared with $K_2Ti_4O_9,\;Na_2Ti_3O_7$ exhibits quite different structural and morphological transformation behavior despite their similar layered structural characteristics. $TiO_2(B)$ obtained by heat treatment of $H_2Ti_3O_7\;at\;350^{\circ}C$ transforms to rutile $H_2Ti_3O_7\;at\;900^{\circ}C$. This temperature is much lower than $1200{\circ}C$, the temperature for anatase to rutile transition when $K_2Ti_4O_9$ is used as a starting titanate. A rectangular rod shape and size of $TiO_2(B)$ particles obtained from $Na_2Ti_3O_7$ is also different from a fibrous structure of $TiO_2(B)$ prepared using $K_2Ti_4O_9$. Rutile crystals of 100 nm diameter with a corn-like morphology and large surface area are directly obtained when the hydrolysis of $Na_2Ti_3O_7$ is carried out at $100^{\circ}C$ in a strong acid solution. The structure of starting titanates and the hydrolysis conditions are an important factor to decide the particle size and morphology of $TiO_2(B)\;and\;TiO_2$.