• YAKHAK HOEJI
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• v.49 no.2
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• pp.122-127
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• 2005

Dental caries is one of the most common oral diseases in the world. Glucosyltransferase (Gtase) of Streptococcus mutans (S. mutans) plays an important role in the develo pment of dental caries. For the purpose to develop anti- caries, we examined the effect of metabolites isolated from Streptomyces sp. M-20 on Gtase and the growth of S. mutans. Streptomyces sp. M-20 isolated from Mongolian soil showed 95~96% sequence homology with that of Streptomyces lin- colnensis. The metabolites of Streptomyces sp. M-20 were partially purified by extraction with ethyl acetate, silica gel column chromatography and preparative TLC. Partially purified metabolite, red colored component (MR-20) in ethyl acetate fraction showed potent antibacterial activitiy against S. mutans and inhibitory activity against Gtase purified from S. mutans, while another isolated yellow component (MY-20) showed no activity against S. mutans. The inhibitory activity of MR-20 against Gtase was confirmed by activity staining on SDS-polyacrylamide gel electrophoresis. The concentration of MR-20 for 50% inhibition $(IC_{50})$ against Gtase activity was $60{\mu}g/ml$. These results suggest that MR-20 can be developed for antibacterial agent and anticaries.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.641-646
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• 2012

We used the hybrid density-functional (B3LYP/6-31G(d,p)) method to analyze the substitution patterns of $C_{20}H_{18}X_2$ derivatives (X = F, Cl, Br, or OH) obtained as disubstituted $C_{20}H_{20}$ cages. Our results suggest that the cis-1 regioisomers (1,2-dihalo derivatives) are less stable than the trans-1 regioisomers (1,20-dihalo derivatives), whereas in the case of the dihydroxy derivatives, the cis-1 regioisomer is more stable than the trans-1 regioisomer. This implies that in the dihalo-induced strain cages of $C_{20}H_{18}X_2$, the strain effect would affect the relative energies, while in the dihydroxide, the hydrogen bonds have a stronger effect on the relative energies in cis-1 regioisomer than the strain effect do. Thus this supports the experimental result in which the bisvicinal tetrol was of particular preparative-synthetic interest as a substitute for the lacking bisvicinal tetrabromide. Further, the topologies of the HOMO and LUMO characteristics of all $C_{20}H_{18}Cl_2$ and $C_{20}H_{18}Br_2$ regioisomers with the same symmetry are same, but they are different from those of $C_{20}H_{18}F_2$ and $C_{20}H_{18}(OH)_2$. This indicates that the five regioisomers of each $C_{20}H_{20}$ disubstituted derivative will have an entirely different set of characteristic chemical reactions.

• YAKHAK HOEJI
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• v.39 no.4
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• pp.417-426
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• 1995

6-[(N-4-Chlorophenyl)amino]-7-chloro-5,8-quinolinedione (RCK20) was tested for antifungal activities, in vivo, against Candida albicans. RCK20 was compared vath ketoconazole and fluconazole in the treatment of systemic infection with Candida albicans in normal rats. The therapeutic potential of RCK20 had been assessed by evaluating their activities (survival rate) against systemic infections with in normal mice with Candida albicans. RCK20 improved survival rates as well as ketokonazole. RCK20 had ED$_{50}$. 0.25$\pm$0.18 mg/kg but ketoeonazole and fluconazole had ED$_{50}$, 8.00$\pm$0.73, 10$\pm$0.43 mg/kg respectively. Activities of RCK20 showed superior to that of ketoconazole and fluconazole. Intraperitoneauy administered RCK20 at the ED$_{50}$, 0.25 mg/kg for 7days and 14days reduced Candida albicans colony count in the kidneys and livers as well as ketoconazole and fluconazole at these ED$_{50}$, 8.00 and 10 mg/kg. Acute oral toxicity studies of RCK20 were carried out in ICR mice of both sexes. These acute oral toxicities of RCK20 were low and LD$_{50}$ values were over 2.850 mg/kg in ICR mice. The Genotoxicities of RCK20 had been evaluated. RCK20 was negative in Ames test with Salmonella typhimurium (TA98 and TA100). The clastogenicity was tested on the RCK20 with in vivo mouse micronucleus assay. RCK20 did not show any clastogenic effect in mouse peripheral blood and was negative in mouse micronucleus assay. These results indicate that RCK20 has no genotoxic potential under these experimental condition.

• Research in Plant Disease
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• v.28 no.3
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• pp.122-131
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• 2022

Colletotrichum acutatum s. lat. 20JDS8 sensitive and 20CDJ6 resistant to pylaclostrobin were used to investigate the cross-resistance with fungicides belonging to the strobilurins and the characteristics of fungicidal controlling activities with different mechanisms against the isolate resistant to the fungicide. The resistant isolate of 20CDJ6 also showed the resistance to azoxystrobin, trifloxystrobin, and kresoxim-methyl, suggesting that there is a cross-resistance relationship. All fungicides with different action mechanisms inhibited mycelial growth of both susceptible and resistant isolates of C. acutatum s. lat., but their disease control effects in fruits were different according to the fungicides. The disease control effect of isopyrazam against 20JDS8 and 20CDJ6 was very low, and fluazinam showed a control effect of 91.9% and 88.1% against 20JDS8 and 20CDJ6 only when it was treated before inoculation by spraying spore suspensions on pepper fruits without wounds. Tebuconazole and prochloraz effectively inhibited not only the mycelial growth of 20JDS8 and 20CDJ6 on potato dextrose agar medium, but also disease incidence in red pepper fruits. As a result of this study, C. acutatum s. lat. 20CDJ6 resistant to pyraclostrobin showed cross-resistance with other strobilurin fungicides. In addition, we think that fluazinam, tebuconazole, and prochloraz can be recommended as alternative fungicides for the control of red-pepper pyranthracnose pathogens resistant pyraclostrobin. However, fluazinam can be effective only if it is treated protectively before the occurrence of the disease.

• Korean Journal of Poultry Science
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• v.38 no.4
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• pp.265-273
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• 2011

This study was carried out to determine the effect of dietary supplementation of quercetin and methoxylated quercetin extracted from onions on chicken thigh meat quality during cold storage. For 35 days, 1-day-old 320 broiler chicks (Ross) were divided into 8 groups and supplemented the diet; basal diet only (CONTROL), CONTROL with antibiotics (AB), vitamin E 20 IU (VE20), vitamin E 200 IU (VE200), quercetin 20 ppm (QC20), quercetin 200 ppm (QC200), methoxylated quercetin 20 ppm (MQ20), and methoxylated quercetin 200 ppm (MQ200). After slaughtering the broilers, thighs were separated and analyzed the quality change of the meat during storage at $4^{\circ}C$ for 7 days. The meat quality factors such as pH, color, water holding capacity, and sensory characteristics of thigh meat were determined on the experiment day 0, 3, and 7. After slaughtering, the pH of AB, VE 20, QC 20, and MQ 200 showed no significant difference compare to that of CONTROL. However, VE 200 and QC 20 showed higher pH value than CONTROL on storage day 3. $L^*$ value of chicken thigh of MQ 20 was lower than CONTROL on storage day 0, however, no significant difference was found between CONTROL and treatments on storage day 3. Redness ($a^*$) of chicken thigh in CONTROL was increased during storage. QC 20, QC 200, and MQ 200 significantly reduced the $b^*$ value of chicken thigh (p<0.05). Water holding capacity of VE 20 and MQ 200 was significantly higher than the CONTROL on the day 0. Also, QC 200 showed higher WHC compare to the CONTROL. In sensory evaluation, overall acceptability of chicken thigh in quercetin and methoxylated quercetin group showed no significant differences compare to that of CONTROL by storage day 3. These results suggested that the quercetin and methoxylated quercetin could be used as additives to enhance broiler thigh meat quality such as pH and WHC without adverse effect on color and sensory characteristics.

• Culinary science and hospitality research
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• v.18 no.5
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• pp.267-278
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• 2012

The purpose of this study was to investigate the quality characteristics of Sulgidduck made with commercial dry rice powder, providing an optimal milk ratio and soaking time for dry powder in water to make Sulgidduck using dry rice powder. The Sulgidduk samples with dry rice powder were prepared with two soaking times (0, 30 min) and different amounts of milk (0, 20, 40, 60%), and analyzed for moisture content, Hunter's color value, texture characteristics and sensory evaluation. The moisture content of the samples ranged from 36.37% to 39.80% and the highest moisture quantity was showed in the group with 20% of milk and 30min of soaking time(SM20). The L-value was the highest in the group with 20% of milk and 0min of soaking time(M20). The b-value was increased with the amount of milk and soaking time increased, showing the highest in the group with 60% of milk and 30min of soaking time(SM60). TPA showed that SM20 had the lowest hardness and the highest adhesiveness. Chewiness, gumminess and cohesiveness were the highest in the group with 60% of milk and 0min of soaking time(M60). Based on quantitative descriptive sensory evaluations, the score of white color and moistness was showed high in the group with 0% of milk and 0min of soaking time(M0), and white powder on the surface was shown the most in the group with 20% of milk and 30min of soaking time(SM20). The score of moistness, springiness and chewiness were highest in the group with 20% of milk and 0min of soaking time(M20). Sulgidduk made with 20% of milk and 0min of soaking time(M20) was the most preferable in color, flavor, taste, and overall acceptability.

• Science of Emotion and Sensibility
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• v.13 no.3
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• pp.485-492
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• 2010

This thesis analyzes the proportion and disproportion of faces through visual analysis and measured value for women faces in 20s and 60s.. The proportion of bizygion breadth and face height is 1 : 1.34 in 20s and 1 : 1.39 in 60s which shows face height is ling in 60s, and 0.85 : 1 : 1 for upper face length, middle face length and lower face length in 20s which shows the proportion of upper face length and lower face length are long while they are 0.84 : 1 : 1.06 in 60s which shows lower face length is long and upper face length is short. If the proportion of the face is more than $2^{\circ}$ which is severe imbalance, angle of eyes is 8% in 20s, 13% in 60s, and angle of nasal is 11% in 20s, 29% in 60s, angle of mouse is 11% in 20s and 40% in 60s, showing imbalance of 60s is severe. As above, It shows that face height is longer in 60s than in 20s and lower face is long among others because face's change due to aging. Also, We able to know that face's imbalance is severer in 60s than in 20s.

• Journal of Veterinary Clinics
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• v.26 no.1
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• pp.23-28
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• 2009

Peritoneal dialysis (PD) is a clinical technique that therapeutically removes toxic solutes from body fluids and normalizes endogenous solutes whose aberrant concentrations disrupt normal physiology. This study retrospectively evaluated clinical outcomes and complications of PD in 20 dogs with renal failure. Blood works (total count of red blood cells (RBC), packed cell volume (PCV), the serum biochemical, and electrolyte values related to renal insufficiency) and complications associated with peritoneal dialysis, and clinical outcomes were recorded before and after PD. Additionally, creatinine reduction ratio (CRR) and urea nitrogen reduction ratio (URR) were calculated for evaluating the efficacy of PD. PD resulted in a significant (p < 0.05) reduction in blood urea nitrogen (BUN) concentration in 19 dogs, while a significant (p < 0.05) reduction in creatinine concentration in 17 dogs. The complications of PD were hypoalbuminemia (12/20, 60%), anemia (10/20, 50%), subcutaneous dialysate leakage (9/20, 45%), bacterial peritonitis (6/20, 30%), dialysate retention (5/20, 25%) and limb edema (4/20, 20%). This study demonstrated that PD was effective in reducing the magnitude of azotemia in dogs with renal failure especially in acute phase, although the complication rate was high but manageable.

• Korean journal of food and cookery science
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• v.23 no.2 s.98
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• pp.245-251
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• 2007

The purpose of this study was to examine how potato glycoalkaloid(PGA) contents changed as storing temperatures and periods changed for potatoes(Superior) cultivated in Korea. Some potatoes were stored at $5^{\circ}$C for 80 days, and others were stored at $20^{\circ}$C for 40 days. PGA contents were measured every 20 days for the potatoes stored at $5^{\circ}$C and 10 days for those stored at $20^{\circ}$C. The results can be summarized as follows. The amounts of a-chaconine and a-solanine measured on the first day of storage were 54.22 mg/100 g and 26.57 mg/100 g, respectively. Thus, the a-chaconine content was almost twice as much as the a-solanine content. The sprouts of potatoes stored at $5^{\circ}$C grew by 0.4 cm in 20 days, 1 cm in 40 days, 1.8 cm in 60 days, and 5.2 cm in 80 days. Furthermore, the PGA content increased by 3.5% in 20 days, 11.6% in 40 days, 23.4% in 60 days, and 41.4% in 80 days, compared to the PGA content on the first day. The sprouts of potatoes stored at 20 grew by 0.5 cm in 10 days, 2.3 cm in 20 days, and 7.4 cm in 40 days. Furthermore, PGA content increased by 12.5% in 10 days, 36.6% in 20 days, 44.8% in 30 days and 48.4% in 40 days, compared to the PGA content on the first day. Thus, we determined that potatoes stored at $20^{\circ}$C showed faster sprout growths and faster increases in PGA content than those stored at $5^{\circ}$C.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.644-651
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• 2007

To establish the optimum conditions for storing buttercup squash, we examined the effectiveness of several storage methods and the quality of the squash under various storage conditions, including temperature (12 and $20^{\circ}C$) and relative humidity (20, 40, 60, and 80%). The spoiling rate of the squash was affected more by the storage temperature than the relative humidity, and the squash stored at $20^{\circ}C$ started to be deteriorated after 20 days of storage. At $20^{\circ}C$, soluble solid content gradually increased until 20 days of storage, and then it tended to decrease. The L-value had a tendency to increase with days of storage, and the a- and b-value also increased after 40 days. In addition, the color changes were great when the squash was stored at high temperature and high relative humidity. The total pectin content increased until 20 days at $20^{\circ}C$, and then it decreased, but less change was observed in the squash stored at $12^{\circ}C$. Overall, the results showed that storage at $20^{\circ}C$ after field curing resulted in excessive weight loss, color loss and poor eating quality, as well as a high level of decay (approximately 70%) after 40 days. However, the squash stored at $12^{\circ}C$ and 60% RH (relative humidity) showed less degreening and had a reduced level of decay, below 10%.