• Korean Journal of Food Science and Technology
• /
• v.23 no.3
• /
• pp.355-359
• /
• 1991

Effects of temperature and pH on thermal degradation of monosodium glutamate(MSG) were investigated during heating of 2% MSG solution at $100{\sim}200^{\circ}C\;and\;pH\;4{\sim}9$. The results showed that the degradation of MSG was very significantly affected by heating temperature and pH. Three hours of heating at $pH\;4\;and\;120^{\circ}C$ resulted appr. 73% MSG degradation while 3 hours at $100^{\circ}C$ decreased only 12%. The comparison study of initial rate of MSG degradation and degradation rate constants showed the highest degradation rate and rate constant and low values in the range of $pH\;6{\sim}8{\sim}$. The values of activation energy calculated from linear relationship of rate constants and 1/T were 18.3 and 9.2 kcal/mole for pH 4 and 5, respectively.

• Radiation Oncology Journal
• /
• v.16 no.3
• /
• pp.233-243
• /
• 1998

Purpose : To evaluate the effects of X-irradiation on prenatal deaths, i.e., preimplantation deaths, embryonic deaths and fetal deaths, and on external malformations in precompacted preimplantation ddy mice Materials and Methods : Pregnant mice (n=85) obtained by limiting the mating time to from 6 to 9 A.M., were segregated into 11 groups. The first five groups (n=26) were irradiated with X-ray doses of 0.1 0.5, 0.75, 1.5, and 3 Gy, respectively, at 24 h post conception (p.c.) of the preimplantation Period. The second five (n=27) groups were irradiated at the same X-ray doses, respectively, but at 48 h p.c. of the preimplantation period. The last group (n=32) was the control group. The uterine contents were examined on the 18th day of gestation for prenatal deaths and external malformations. Results : 1) A statistically significant increase in preimplantation deaths with increasing dose was observed in the experimental groups irradiated at 24 h p.c. and in the groups irradiated at 48 h p.c., as compared to the control group. The threshold dose was close to 0.05 Gy and 0.075 Gy for the irradiations at 24 h p.c. and 48 h p.c. respectively. 2) A statistically significant increase in embryonic deaths with increasing dose was observed in all irradiation groups, except the group irradiated with a dose of 0.1 Gy at 48 h p.c.. 3) No fetal deaths were found in any experimental group. 4) In the experimental groups irradiated at 24 h p.c. anomalies increased with statistical significance, as compared with the control group : 2 exencephalies, 2 open eyelids, 3 anophthalmias, 2 cleft Palates, 2 gastroschisis, 1 abdominal wall defect. 1 leg defect, and 2 short tail anomalies: the threshold dose for external malformations was close to 0.2 Gy at 24 h p.c.. In the groups irradiated at 48 h p.c., 1 open eyelid and 2 short tail anomalies were observed, but there was no statistical significance in those malformations. Conclusion : The results of this study reveal that X-irradiation of precompacted preimplantation ddy mice causes not only preimplantation deaths and embryonic deaths but also external malformations. In addition, external malformations were observed in our experiments at diagnostic doses, including 0.1 and 0.5 Gy. For this reason, we recommend that irradiation should be avoided during the preimplantation period by applying Rugh's 10-day rule.

• Food Science and Preservation
• /
• v.15 no.4
• /
• pp.491-496
• /
• 2008

To develop a freshness indicator of Chonggak-kimchi for marketing purposes, Chonggak-kimchi was prepared and pH, total acidity, total aerobic bacterial load, lactic acid bacterial levels, and reducing sugar content were measured. Sensory evaluation tests on product stored at $4^{\circ}C,\;10^{\circ}C,\;and\;20^{\circ}C$, were performed. The pH increased slightly early in storage, and then decreased to pH 4.2-4.3 for all samples. The rate of decrease of pH rose with increasing storage temperature. Total acidity values rapidly increased after 1, 5, and 7 days of storage at $20^{\circ}C,\;10^{\circ}C,\;and\;4^{\circ}C$, respectively. Populations of total aerobic bacteria and lactic acid bacteria increased slightly until 4 days, 10 days, and 30 days of storage at $20^{\circ}C,\;10^{\circ}C,\;and\;4^{\circ}C$, respectively, and then decreased drastically. Sensory evaluation data showed that Chonggak-kimchi was edible until 4 days(pH 4.5), 10 days(pH 4.4), and 30 days(pH 4.3) of storage at $20^{\circ}C,\;10^{\circ}C,\;and\;4^{\circ}C$, respectively. These results clearly suggest that the shelf-life of Chonggak-kimchi depends on storage temperature, and the pH limit for marketing is 4.3; this is a freshness indicator for Chonggak-kimchi.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.27 no.3
• /
• pp.209-218
• /
• 2007

This experiment was conducted to investigate effect of plowing frequency and sowing dates on the agronomic characteristics, feed value, weed yield and palatability of silage corn. Treatments were a basal treatment(C: May 5 seeding, plowing once, weeding control once), T1(May 12 seeding, plowing twice, weeding control 0 time), T2(May 19 seeding, plowing three times, weeding control 0 time, T3(May 26 seeding, plowing four times, weeding control 0 time) and T4(June 2 seeding, plowing five times, weeding control 0 time). The experiment was performed at the College of Life and Natural Sciences of Sangju University in Sangju in 2006. The plant height and ear height showed highly in order to C > T1 > T2 > T3 > T4 treatment, leaf length was the highest at T2 (96.0cm). Leaf width and number of dead leaf were the highest at C and T3 (11.2cm), C, C and T1 (4.6), respectively. Stem diameter was the highest at T3 as 31mm, while T2 was the lowest as 25mm (p<0.05). Ear circle showed highly in order of C > T1 > T4 > T3 > T4 (p<0.05), and tip filling degree was the highest at C treatment as 8.8, while T4 treatment was the lowest as 6.0 (p<0.05). The stem hardness and grain hardness were C < T1 < T2 < T3 < T4 (p<0.05). Stem saccharinity was T1(6.1%) was the highest, while T2(3.0%) was the lowest(P<0.05). Fresh yield of weed was the lowest at C treatment as 500 kg/ha, but T1 treatment was the highest as 44,100 kg/ha (p<0.05). Weed coverage rate showed highly in order of T1 > T2 > T3 > T4 > C treatment (p<0.05). Fresh yield of corn was the highest at C treatment as T3,550 kg/ha, but T4 treatment was the lowest as 65,500 kg/ha (p<0.05). Dry matter yield of corn showed highly in order of C(26,978 kg/ha) > T1(26,130 kg/ha) > T2(20,255 kg/ha) > T3(20,255 kg/ha) > T4(17,508 kg/ha) treatment (p<0.05). Crude protein content was T1(7.69%) > T4(7.42%) > T2(6.34%) > T3(5.99%) > C(5.91%) treatment (p<0.05), and Crude fat content showed highly in order of C (2.13%) > T1(2.04%) > T2(1.96%) > T3(1.95%) > T4(1.84%) treatment. Relative palatability of Holstein, Korean native goat and spotted deer was the highest at C treatment, but Korean native cattle was the highest at T1 treatment.

• Journal of Digital Convergence
• /
• v.12 no.3
• /
• pp.7-16
• /
• 2014

This study aims to analyze the key logic of the current C-P-N-D ICT ecological system, to find out the shortcomings of the current system, and then to offer policy suggestions for the establishment of a new creative contents industry ecological system; that is, ICCT (Information, Communication, Contents and Technology) System.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.11
• /
• pp.2060-2069
• /
• 2017

Newcastle disease is a serious infectious disease in the poultry industry. The commercial vaccines can only offer limited protection and some of them are expensive and need adjuvants. At present, DNA vaccines are widely used. However, the immune responses induced by DNA vaccines are too slow and low. Here, we constructed the transfer vectors with a different number of C3d as molecular adjuvants (n = 1, 2, 4, or 6), and the vectors were cloned into the optimal eukaryotic expression plasmid (pVAXI-optiF) that expressed the F gene of Newcastle disease virus (NDV), and named pVAXI-F(o)-C3d1, pVAXI -F(o)-C3d2, pVAXI-F(o)-C3d4, and pVAXI-F(o)-C3d6, respectively. Cell transfection test indicated that pVAXI-F(o)-C3d6 showed the highest expression. In vivo immunization showed that the chickens immunized with pVAXI-F(o)-C3d6 intramuscularly induced better immune responses than the chickens immunized with the other plasmids. The protective efficacy of pVAXI-F(o)-C3d6 was 80% after challenge with the highly virulent NDV strain F48E9. The results in this study showed that C3d6 could be used as a molecular adjuvant to quickly induce an effective immune response to control NDV.

• Journal of the Korean Ceramic Society
• /
• v.18 no.2
• /
• pp.119-125
• /
• 1981

The thermostable resistor was made by using P.T.C.R-N.T.C.R. ceramics. In this study $BaTiO_3$ type P.T.C.R. ceramics and $SnO_2-Sb_2O_3$ type N.T.C.R. ceramics were cocrystallized in one body and electrical resistance was stable under the temperature variation between $25^{\circ}C$-40$0^{\circ}C$. The ceramics showed the most stable electrical resistance for the mal variation when the composition was 0.6P.T.C.R. $BaTiO_3$,$ 0.4SnO_2$ and 0.01 $Sb_2O_3$.

• Journal of Animal Science and Technology
• /
• v.48 no.6
• /
• pp.847-860
• /
• 2006

This study investigated the effects of feeding Charolais steers on diets rich in either n-6 or n-3 polyunsaturated fatty acids (PUFA) and time on feed (TOF) on muscle fatty acid composition and content. Twenty eight steers were fed on ad libitum forage and one of two concentrates varying in the source of fat; soya (high in C18:2 n-6) or whole linseed (high in C18:3 n-3) for either 60 or 90 days in IGER (Institute of Grassland and Environmental Research, UK). The concentrates were fed at approximately 0.73 of total DM intake. TOF influenced carcass weight, conformation and fatness scores, which were higher at 90 v. 60 days (P<0.05). Diet did not affect total fatty acid content of neutral lipid in m. longissimus thoracis but feeding linseed increased total phospholipid fatty acid by approx- imately 15%(P<0.05). Linseed increased the amount and proportion of C18:3 n-3 (P<0.001) and the proportion of CLA (cis-9, trans-11 conjugated linoleic acid), while soya increased the content (P<0.05) and proportion (P<0.001) of C18:2 n-6 in muscle neutral lipid. In muscle phospholipid, linseed significantly increased the amount of CLA, C18:3 n-3 and its longer chain derivatives as well as C14:0, C16:0, C18:0. C18:1 trans and C18:2 n-6. The amount and proportion of C18:2 n-6 and its longer chain C20 derivatives were higher on feeding soya. TOF (90 v. 60 day) increased the content of C14:0, C16:0, C16:1, CLA, C18:1 n-9, C18:2 n-6 and C18:3 n-3 in muscle neutral lipid. The P:S was not affected by diet or TOF. The ratio of C18:2 n-6 : C18:3 n-3 and sum of n-6 : n-3 fatty acids were higher in muscle from animals fed on linseed v. soya (P<0.001). The study indicates that the PUFA composition of beef muscle may be significantly modified by feeding contrasting dietary lipids, soya vs. linseed. Feeding linseed produced a better balance of muscle fatty acids, more in line with current nutritional recommendations with a lower C18:2 n-6:C18:3 n-3 ratio associated with higher muscle content of C18:3 n-3 and C20:5 n-3 and CLA and lower C20:4 n-6.

• Proceedings of the Korean Society for Applied Microbiology Conference
• /
• 2000.04a
• /
• pp.208-213
• /
• 2000

Penicillium fellutanum produces a phosphorylated, choline-containing extracellular peptido-polysaccharide, peptidophosphogalactomannan (pPxGM) (8). The $\^$13/C-methyl labeled pPxGM ([methyl-$\^$13/C]pPxGM) was prepared from the cultures supplemented with L-[methyl-$\^$13/C]methionine or [2-$\^$13/C]glycine and was used as a probe to monitor the fate of phosphocholine in this polymer. Addition of purified [methyl-$\^$l3/C]pPxGM to growing cultures in low phosphate medium resulted in the disappearance of [methyl-$\^$13/C]phosphocholine and -N,N'-dimethyl-phosphoethanolamine from the added [methyl-$\^$13/C]pPxGM. Two $\^$l3/C-methyl-enriched cytoplasmic solutes, choline-O-sulfate and glycine betaine, were found in mycelial extracts, suggesting that phosphocholine-containing extracellular pPxGM of P.fellutanum is a precursor of intracellular choline-O-sulfate and glycine betaine and thus of phosphatydilcholine (l0). $\^$13/C-Methyl-labeled cells grown in 3 M NaCl-containing medium showed 2.6- and 22-fold more accumulation of $\^$13/C-methyl labeled choline-O-sulfate and glycine betaine, respectively, originated from the extracellular [$\^$13/C-methyl]pPxGM than those grown without added NaCl. The results suggest that, in addition to glycerol and erythritol, glycine betaine and choline-O-sulfate and thus choline are also osmoprotectants and hence that pPxGM is involved in osmotolerance of this fungus (11). Taken collectively, the $\^$l3/C- and $\^$31/P-NMR analyses of cytosolic solute pools and structural modulation of extracellular pPxGM corresponding to environmental stimuli in P. fellutanum, provided evidence that pPxGM is involved in cellular choline metabolism, osmotolerance, and recycling of metabolites.

• Journal of Ginseng Research
• /
• v.25 no.3
• /
• pp.136-140
• /
• 2001

Effects of incubation temperature and pH on chlamydospore germination of Cylindrocarpon destrcutans (isolate CY-9802) causing root rot of Panax ginseng were studied. Germination rate of the chlamydospores on Czapek solution agar(CSA) was higher than on potato dextrose agar(PDA) at the incubation temperatures tested. The chlamydospores were able to be germinated at range of 5$\^{C}$ to 30$\^{C}$ after 48 hours incubation on CSA. Germination rate was 53.2∼6.27% at range of 15$\^{C}$ to 25$\^{C}$, and the optimum temperature was 20$\^{C}$, whereas they were very low at 30$\^{C}$ on PDA. Germination rate was 43.6% to 47.9% at range of 10$\^{C}$ to 20$\^{C}$, and the optimum temperature was 20$\^{C}$ as well. They were able to be germinated at pH of 5.2 to 8.1 on CSA and 5.2 to 7.2 on PDA. Optimum pHs for the germination on CSA and PDA were from 6.4 to 8.2 and from 5.2 to 6.0, respectively. Mycelial color of the fungus on CSA was pale brown at pH from 5.2 to 6.0 and white from pH 6.4 to 8.1, while it was typical dark brown ar range of pH 5.2 to 7.1 and brown at pH 7.2 on PDA after 21 days incubation.