• 대한화학회지
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• 제24권4호
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• pp.269-279
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• 1980

$t^2_2$ 전자배치를 가진 팔면체 및 일그러진 팔면체 $[V(III)A_3B_3]$형태 착물에 대한 자기모멘트를 계산하는 새로운 방법을 발전시켰다. [A 와 B = O, Cl, N, F 또는 Br]. 이 방법에 의하여 계산한 자기모멘트가 실험치와 비교적 잘 일치한다. 일그러진 팔면체 $[V(III)A_3B_3]$형태 착물의 계산한 자기모멘트는 tetragonal distortion의 크기가 증가함에 따라 감소한다. 자기모멘트에 대한 k (orbital reduction factor), $\xi'$ 및 온도의 영향을 또한 고찰하였다. 쌍극자모멘트 및 편극율에 대한 $^3T_1$ 분자궤도함수의 기여분을 계산하는 새로운 방법을 발전시켰다. 이 방법에 의하여 계산한 $^3T_1$ 분자궤도함수의 기여분은 합리적인 범위안에 들었다.

• The Korean Journal of Ecology
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• 제3권1_2호
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• pp.11-16
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• 1980

무시비구, 질소시비구(6.67gN/$m^2$) 및 과질소비구(13.34gN/$m^2$)의 질소구배처리에 따른 대두개체군의 생육과정별 제 생장해석적특징 및 일차생산성을 비교검토하였다. 질소시비구 및 과질소시비구에서는 대조구에 비해 8~10배의 순질소흡수율과 비교적 높은 생산성 및 최대 LAI의 도달이 2주정도 빨리 나타났고 SLA의 증가를 보였으나, 근립의 형성은 1/3~1/4의 감소를 보였다. 그러나, H, F/C, T/R, RGR, NAR, 및 CGR 등 생장해석적특징에는 큰 유의차가 없었다.

• 대한미생물학회지
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• 제18권1호
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• pp.23-29
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• 1983

An epidemiological survey was carried out to identify the serotypes of Streplococcus mutans isolated from carious lesions of 65 caries-active subjects(CAS) and sound tooth surfaces of 40 caries-free subjects(CFS). The autoclaved antigen extract was performed on each isolate, and then, serotypes of the isolates were determined in agar-gel immunodiffusion test. The results were as follows: 1. S. mutans was found in 78% of the samples of CAS, and of CFS. The difference of isolation frequency between CAS and CFS was not observed. 2. Only one serotype per single subject was detected in 61% of total samples, in remaining 39% of samples two or more serotypes were detected. 3. In 41.2% of CAS samples plural serotypes of S. mutans were found, whereas 35.5% of CFS samples showed plural serotypes distribution. 4. The most frequently identified serotype in each subject was serotype c; 69.5% of subjects harbored serotype c S. mutans. Serotype d was next most frequently isolated from subjects, comprising 23.2%. 5. Serotype c strain was found in 64.7% of CAS, 77.4% of CFS. 6. Of the isolates from CAS and CFS, serotype c was most commonly found, comprising 48.8%, serotype d was found in 16.3%, serotypes f. e, and g comprising 13.2%, 9.3%, and 7.8% respectively. Serotypes a and b were also found but in far lower frequencies(2.3%, 0.8%). 7. Serotype c strains were more found in CFS than in CAS, but serotypes d and e were more found in CAS.

• 한국환경보건학회지
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• 제42권3호
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• pp.160-168
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• 2016

Objectives: Materials coming into contact with food may result in the migration of chemical substances into the food. To protect consumers from exposure, Regulation (EU) No. 10/2011 specifies the use of standard migration tests. Polyethylene terephthalate (PET), widely used for food packaging materials, has drawn the attention of researchers because unwanted migration of PET into food might occur when consumers reuse packaging material. The aim of this study was to predict and develop a migration model for two components, acetaldehyde and butyraldehyde in PET, into food simulants under conditions of changing pH and solvents, such as those observed in fermented foods like kimchi or sauerkraut. Methods: Using a migration model based on Fick's second law of diffusion in one dimension, the migration of acetaldehyde and butyraldehyde from PET into a simulant of fermented food at $20^{\circ}C$ over 10 days was evaluated. The simulant for fermented food was modelled as 10% ethanol for three days, followed by 3% acetic acid for seven days. Results: The migration of acetaldehyde into the 10% ethanol was 0.36 times that of a simulated fermented food system, while that of butyraldehyde was 1.34 times greater. These results may have been influenced by the chemical interactions among the migrants, polymers and simulants, as well as by the solubilities of the migrants in polymers and simulants. Conclusion: Because food simulants have a limited capacity to mimic real food systems under the current migration model, an appropriate simulant and migration test should be considered in the case of increasing acidity. Furthermore, since the accuracy of the worst-case estimation of migration predicted by the current model is severely limited under changing food conditions, food simulants and their interactions should be further investigated with respect to conservative migration modelling.

• 원예과학기술지
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• 제34권2호
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• pp.331-341
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• 2016

본 연구는 기능성 지표물질 확인을 위한 동양란 심비디움(Cymbidium) 향기 성분 비교 분석을 목적으로 하며, GC/MS 방법을 사용하여 한국춘란(Cymbidium goerigii L.), 중국춘란(C. forrestii R.)과 일경구화(C. faberi R.)의 향기성분을 비교 분석하였다. 분석은 한국춘란으로 '민춘란', '주금화', 중국춘란으로 '취개', '송매', '용자', 일경구화로 '최매', '남양매', '화자'등을 사용하였다. GC/MS 방법을 통해 검출된 성분들을 peak area(%)값 분석을 사용하여 3%이상의 주요 향기성분으로 분류하였다. 향기 성분 분석 결과 한국춘란에서는 유방암, 자궁경부암, 교모세포종암에 세포독성 기능성을 가진 ${\alpha}$-bergamotene과, 인체 간암 세포(HepG2)의 사멸과 성장 억제, 항진균제 및 바베스열원충, 충치균에 대한 억제 기능성을 가진 nerolidol이 가장 많았다. 중국 춘란에서는 nerolidol과 악성 흑색종 세포(B16-F10), 인체 간암 세포와 백혈병 세포(HL-60, K562)의 사멸과 억제 등의 기능성을 가진 ${\beta}$-bisabolene이 가장 많았다. 일경구화에서는 교모세포종(SF-767)의 억제와 간암세포주(BEL-7402)에 소염작용 억제 효과를 가진 ${\alpha}$-pinene, 위장 보호 효과 기능을 가진 1,8-cineole과 페로몬의 기능을 가진 1,3,7-octatriene이 가장 많았다. 이상에서 동양란의 주요 향기 성분으로 밝혀진 물질들은 인간에게 유익한 다양한 기능성을 갖고 있는 것으로 확인되었다.

• Toxicological Research
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• 제20권1호
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• pp.71-82
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• 2004

Changes in cell cycle control in the lungs and liver of the B6C3F1 mice (20 males per each group) exposed to ozone (0.5 ppm), 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 1.0 mg/kg), and dibutyl phthalate (DBP, 5,000 ppm) after 52 weeks were examined through Western, Northern blot, and immunohistochemistry based on alterations in protein expression levels of G1/S checkpoints (cyclin D1, cyclin E, and PCNA), G2/M checkpoints (cyclin B1, cyclin G, and cyclin A), negative regulators (p53, p21, GADD45, and p27), and positive regulator (mdm2). Expression levels of cyclins D1, E, G, PCNA, mutant p53, and mdm2 proteins were higher in the lungs and livers treated with combination of toxicants than in those treated with ozone only. Expression levels of the wild-type and mutant p53, p21, GADD45, p27, and mdm2 proteins and mRNAs were higher in toxicant-treated groups than those of the control. Immunohistochemical analysis revealed staining intensities of the PCNA, cyclin D1, c-myc and mdm2 protein- treated lungs and livers were stronger than those of the control group. Our results showed that combined treatment of ozone with NNK/DBP altered the cell cycle control through instability of the wild-type p53 gene. Such pivotal p53-mediated cell cycle alterations may be responsible for the toxicity observed under our experimental condition. These results may be applied to risk assessment of mixture-induced toxicity.

• BMB Reports
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• 제34권3호
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• pp.206-211
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• 2001

Endostatin, a proteolytic fragment of collagen XVIII, is a potent inhibitor of angiogenesis and the growth of several primary tumors. However, the opinions on the activity of endostatin derivatives deleted N- or C- terminal are still controversial. In this regard, we produced mouse endostatin and its derivatives in the prokaryotic system, and studied their anti-tumor activity. The [$^3H$]-thymidine incorporation assay demonstrated that N-terminal deleted mouse endostatin, and a C- and N-terminal deleted mutant, effectively inhibited the proliferation of human umbilical vein endothelial cells (HUVECs). The biological activity of endostatin was also shown by its in vivo anti-angiogenic ability on the chorioallantoic membrane (CAM) of a chick embryo. Treatment of $200\;{\mu}g$ of mouse endostatin, or N-terminal deleted mouse endostatin, inhibited capillary formation of CAM 45 to 71%, which is comparative to a 80% effect of positive control, $1\;{\mu}g$ of retinoic acid. An in vivo mouse tumor growth assay showed that N-terminal deleted mouse endostatin, and the N-/C-terminal deleted mutant, significantly repressed the growth of B16F10 melanoma cells in mice as did the full-length mouse endostatin. According to these results, N-and N-/C-terminal deleted mouse endostatins are the potent inhibitors of tumor growth and angiogenesis.

• 한국식품과학회지
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• 제42권1호
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• pp.8-13
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• 2010

캔제품 중 Biphenol A diglycidyl ether(BADGE), bisphenol F diglycidyl ether(BFDGE) 및 그 분해산물인 BADGE $H_2O$, BADGE $2H_2O$, BADGE HCl, BADGE 2HCl, BADGE HCl $H_2O$, BFDGE $H_2O$, BFDGE $2H_2O$, BFDGE HCl, BFDGE 2HCl, BFDGE HCl $H_2O$ 등의 HPLC/FLD와 HPLC/APCI-MS에 의한 정성 및 정량방법을 확립하고 133개 캔 제품을 사용하여 분석방법의 재현성을 검토하였다. 수용성 식품의 경우 BADGE $2H_2O$가 13개 제품에서 0.400-0.888 mg/kg, BADGE HCl $H_2O$가 1개 제품에서 0.566 mg/kg, BFDGE $H_2O$가 3개 제품에서 0.489-0.664 mg/kg, BFDGE $2H_2O$가 3개 제품에서 0.455-0.846 mg/kg, BFDGE HCl $H_2O$가 2개 제품에서 0.455-0.752 mg/kg의 농도로 검출되었다. 지용성 식품의 경우에는 BADGE가 3개 제품에서 0.093-0.486 mg/kg, BADGE $H_2O$가 1개 제품에서 0.183 mg/kg, BADGE HCl이 1개 제품에서 0.097 mg/kg, BADGE 2HCl이 7개 제품에서 0.200-0.452 mg/kg, BFDGE가 3개 제품에서 0.438-0.506 mg/kg, BFDGE $2H_2O$가 1개 제품에서 0.295 mg/kg, BFDGE HCl 및 BFDGE 2HCl이 1개 제품에서 0.324 mg/kg의 농도로 검출되었다. 분석방법의 재현성은 우수하였고, 모니터링 결과는 EU 수준과 유사하거나 안전한 수준으로 나타났다.

• 대한수의학회지
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• 제41권1호
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• pp.29-35
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• 2001

The protective effects of egg yolk atibodies obtained from chickens immunized with fimbrial antigens from ETEC 987P were evaluated in 14 and 21 d old pigs in which ETEC diarrhea was induced. For the Exp. 1, eight early-weaned pigs($5.00{\pm}0.5kg$ average BW and 14 d average age) and eight weaned pigs($6.00{\pm}0.5kg$ average BW and 21 d average age) were used to examine influence of egg yolk antibodies on growth performance and resistance to ETEC 987P infection. Dietary treatments included 1) administered of commercial egg yolk(14 d of age; CEY14), 2) administered of egg yolk antibodies(14 d of age; EYA14), 3) administered of commercial egg yolk(21 d of age; CEY21), 4) administered of egg yolk antibodies(21 d of age; EYA21). The 14 and 21 d old pigs were challenged with 2 ml of ETEC 987P at a dose of $10^{10}\;CFU\;ml^{-1}$ per weaned pigs. Weaned pigs treated with egg yolk antibodies recovered and pigs treated with egg yolk antibodies tended to increase average daily gain(P<0.05). Also, EYA12 and EYA21 treatments were reduced coli-form bacteria concentration and increased Lactobacilli sp. concentration from feces. For the Exp. 2, sixteen weaned pigs($6.00{\pm}0.5kg$ average daily gain BW and 21 d average age) were used to examine influence of yolk or white from egg containing antibodies on growth performance and resistance to ETEC 987P infection. Dietary treatments included l) administered of commercial egg yolk(CEY), 2) administered of commercial egg white(CEW), 3) administered of egg yolk antibodies(EYA), 4) administered of egg white antibodies(EWA). Pigs treated only with EYA showed signs of recovery. Also, EYA treatment showed the best average daily gain without significant differences (P>0.05). EYA treatment was reduced coli-form bacteria concentration increased and Lactobacilli sp. concentration from feces. In conclusion, egg yolk antibodies have protective effects from pigs in which ETEC diarrhea was induced.

• The Plant Pathology Journal
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• 제32권3호
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• pp.228-241
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• 2016

In our previous study, we reported that a novel endophytic bacterium Bacillus oryzicola YC7007 has suppressed bacterial diseases of rice via induced systemic resistance and antibiotic production. This endophytic strain, B. oryzicola YC7007 was used as a biological control agent against bakanae disease of rice caused by Fusarium fujikuroi, and its mechanism of interaction with the pathogen and the rice was further elucidated. Root drenching with B. oryzicola YC7007 suspension reduced the disease severity of bakanae significantly when compared with the untreated controls. The treatments of B. oryzicola YC7007 suspension ($2.0{\times}10^7cfu/ml$) to the rice rhizosphere reduced bakanae severity by 46-78% in pots and nursery box tests containing autoclaved and non-autoclaved soils. Moreover, in the detached rice leaves bioassay, the development of necrotic lesion and mycelial expansion of F. fujikuroi were inhibited significantly by spraying the culture filtrate of B. oryzicola YC7007. Drenching of ethyl acetate extracts of the culture filtrate to the rhizosphere of rice seedlings also reduced the bakanae disease severity in the plant culture dish tests. With the root drenching of B. oryzicola YC7007 suspension, the accumulation of hydrogen peroxide was observed at an early stage of rice seedlings, and a hormonal defense was elicited with and without pathogen inoculation. Our results showed that the strain B. oryzicola YC7007 had a good biocontrol activity against the bakanae disease of rice by direct inhibition, and was also capable of inducing systemic resistance against the pathogen via primed induction of the jasmonic acid pathway.