• 분석과학
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• 제11권1호
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• pp.73-78
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• 1998

미오글로빈 시안착물(MbCN) 단백질에 대한 NMR의 HMQC 연구는 수소와 결합된 상자기성 heme 탄소 시그날의 완전한 지정을 가능토록 해준다. 이러한 상자기성 MbCN에 대한 HMQC 실험의 적용은 heme시그날뿐만 아니라 상자기성 아미노산에 대해 결합된 수소와 탄소간의 coherence를 지정하여주며 자연존재량 $^{13}C$시그날의 지정이 모든 low-spin 상자기성 heme단백질에서도 가능하다. 이러한 시그날 지정 전략은 정자기성 영역에서 공명하는 수소 시그날의 지정을 위해 사용되는 NOE에만 의존하는것 보다 훨씬 명확한 시그날지정이 가능하다. 2,4-비닐기의 ${\alpha}$-탄소들과 7-프로피온기의 ${\beta}$-탄소에서 특이한 anti-Curie형태를 보이는 것은 그들이 heme평면에 존재하고 있지 않다는 증거가 된다. Proximal His에 의해 유도된 heme의 전자 및 자성의 비대칭은 heme탄소 시그날공명이 $25^{\circ}C$에서 250 ppm의 범위에 이르도록 한다. 이러한 heme 탄소 시그날 공명은 미오그로빈 heme의 전자구조를 분석하는데 있어서 수소 시그날의 공명보다 더욱 민감한 증거로 작용할수 있다.

• 폴리머
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• 제35권4호
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• pp.337-341
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• 2011

수직배향 액정디스플레이의 시야각 향상을 위한 광대역 보상필름을 개발하였다. 상용화된 수직배향 액정디스플레이는 측면 시야각을 보상하는 위상차 필름을 필요로 한다. 일반적으로 triacetylcellulose(TAC)에 광학첨가제를 첨가한 후 제막연신을 통하여 수직배향 액정디스플레이용 위상차 필름을 제작하는데, 첨가되는 광학첨가제의 화학구조에 따라 필름의 위상차와 파장분산 특성이 달라진다. 본 연구에서는 첨가제에 따른 분극률 이방성을 양자역학적으로 계산하고 선택된 중심 이성질체에 사이드 그룹을 치환시켜 파장별 분극률 이방성을 또한 계산하였다. 특히, 치환기가 methoxy와 proplonate인 경우에 치환위치와 숫자에 따른 파장별 분극률 이방성을 비교하였다. 2개의 propionate 그룹이 meta위치에 있을 경우가 파장분산 특성이 가장 완만한 것을 양자역학적 계산을 통하여 예측하였으며 이를 실험을 통해 증명하였다. 파장분산 특성이 완만하다는 것은 LCD 시야각 특성이 광원의 파장에 따라 덜 변한다는 의미이며, 현재 수준보다 우수한 화질을 구현할 수 있다.

• 한국잡초학회지
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• 제18권2호
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• pp.161-170
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• 1998

Fenoxaprop-P-ethyl에 대한 bentazon의 길항작용기작을 검정하기 위하여 4엽기의 벼와 피를 대상으로 bentazon 혼합처리에서 나타나는 fenoxaprop-P-ethyl의 흡수, 이행, 대사 및 작용점의 활성 변화를 조사하였다. Fenoxaprop-P-ethyl에 대하여 벼와 피의 지상부에서 생육억제가 크게 나타났다. Fenoxaprop-P-ethyl 단독처리에 있어서 두 초종 모두에서 처리 직후부터 빠른 속도로 약제가 흡수되어, 총 흡수량의 90%이상이 약제처리 6시간 이내에 이루어졌으며, 처리 24시간까지 흡수량의 약 30%가 처리엽의 상, 하위조직으로 이행되었다. Ethyl ester형으로 처리된 약제는 신속히 acid형으로 전환되었으며, 처리 24시간 후부터는 acid형이 conjugate형의 대사물로 전환되었다. 그러나 bentazon에 의한 fenoxaprop-P-ethyl의 흡수, 이행 및 대사활성의 변화는 인정되지 않았다. In vitro ACCase의 활성은 벼와 피 에서 각각 26.5 및 23.2nmol/min/mg protein으로 나타났다. 이 효소 활성의 50% 저해농도에 있어서 fenoxaprop-P-ethyl 단독처리와 bentazon 혼합처리 사이에 유의성은 인정되지 않았다. 그러나 bentazon 처리에 의하여 in vivo ACCase 활성의 감소와 엽록체 thylakoid에서 전자전달의 억제가 나타났다. 따라서 fenoxaprop-P-ethyl에 대한 bentazon의 길항작용기작은 bentazon이 fenoxaprop-P-ethyl 작용점의 활성에 직접적으로 관여하는 것이 아니라, 엽록체 구조 및 활성 저해에 의한 fenoxaprop-P-ethyl의 작용점 감소를 통하여 간접적으로 fenoxaprop-P-ethyl의 활성을 억제하는 것으로 판단된다.

• Toxicological Research
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• 제21권3호
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• pp.187-193
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• 2005

The rodent Hershberger assay is considered as a potential short term in vivo screening method for the detection of androgenic or anti-androgenic compounds. The objective of this study was to evaluate the anti-androgenic activities of di(2-ethylhexyl) phthalate (DEHP), di(n-butyl) phthalate (DBP), and butylbenzyl phthalate (BBP). A 10-day Hershberger assay was performed using immature Sprague-Dawley male rats castrated at 6 weeks of age. Tastosterone propionate (TP, 0.4 mg/kg/day) was administered s.c. to castrated male rats and followed by flutamide (1, 5, 10, or 20 mg/kg/day) treatment for 10 days by oral gavage. Similarly, DEHP, DBP, or BBP were also administered by oral gavage at 250, 500, or 1000 mg/kg/day after TP (0.4 mg/kg/day) administration. As expected, flutamide significantly inhibited the TP-induced re-growth of seminal vesicles, ventral prostate, and Levator ani plus bulbocavernosus muscles (LABC) at 1 mg/kg/day and above, and Cowper's glands and glans penis at 5 mg/kg/day and above. DEHP significantly (p<0.05) decreased the seminal vesicles, ventral prostate, LABC and Cowper's glands weights at 1000 mg/kg/day. BBP at 1000 mg/kg/day significantly inhibited TP-induced re-growth of the LABC in the immature castrated male rats, whereas ventral prostate, seminal vesicles, and Cowper's glands weights were unaffected. In contrast to DEHP, DBP did not affect accessory sex organ weights at any concentration. Body weights, combined adrenal glands, and kidney weights were not affected, but liver weights were significantly increased at high dosages in the DEHP, DBP, and BBP treatment groups. Our observations strongly suggest that DEHP acts as an androgen antagonist at the high dose (i.e., 1000 mg/kg/day).

• 한국축산시설환경학회지
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• 제18권sup호
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• pp.35-40
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• 2012

본 연구는 사료에 서양고추냉이 분말 0.03%, 팽이버섯폐배지 0.5% 및 서양고추냉이 분말 0.03%와 팽이버섯폐배지 0.5%의 혼합제를 사료에 각각 첨가한 후 비육돈에 급여하여 분뇨에서 발생되는 악취물질의 농도변화를 조사하였다. 1. 분뇨의 단쇄지방산 농도를 측정한 결과 초산, 프로피온산, 부티르산 및 이성체지방산의 농도는 처리구간에 차이가 없었다(p>0.05). 2. 분뇨의 페놀, p-크레졸 및 이들을 합한 페놀류 농도는 처리구간에 차이가 없었다(p>0.05). 그러나 인돌 농도는 고추냉이 처리구에서 낮았으며(p<0.05), 스카톨 농도는 대조구와 고추냉이구에서 가장 높았고, 고추냉이와 버섯폐배지의 혼합구에서 가장 낮았으며, 버섯폐배지구는 중간이었다(p<0.05). 인돌류 농도는 고추냉이와 버섯폐배지의 혼합구에서 가장 낮았다(p<0.05).

• Journal of Microbiology and Biotechnology
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• 제29권7호
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• pp.1083-1095
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• 2019

Butyrate is known to play a significant role in energy metabolism and regulating genomic activities that influence rumen nutrition utilization and function. Thus, this study investigated the effects of an isolated butyrate-producing bacteria, Clostridium saccharobutylicum, in rumen butyrate production, fermentation parameters and microbial population in Holstein-Friesian cow. An isolated butyrate-producing bacterium from the ruminal fluid of a Holstein-Friesian cow was identified and characterized as Clostridium saccharobutylicum RNAL841125 using 16S rRNA gene sequencing and phylogenetic analyses. The bacterium was evaluated on its effects as supplement on in vitro rumen fermentation and microbial population. Supplementation with $10^6CFU/ml$ Clostridium saccharobutylicum increased (p < 0.05) microbial crude protein, butyrate and total volatile fatty acids concentration but had no significant effect on $NH_3-N$ at 24 h incubation. Butyrate and total VFA concentrations were higher (p < 0.05) in supplementation with $10^6CFU/ml$ Clostridium saccharobutylicum compared with control, with no differences observed for total gas production, $NH_3-N$ and propionate concentration. However, as the inclusion rate (CFU/ml) of C. saccharobutylicum was increased, reduction of rumen fermentation values was observed. Furthermore, butyrate-producing bacteria and Fibrobacter succinogenes population in the rumen increased in response with supplementation of C. saccharobutylicum, while no differences in the population in total bacteria, protozoa and fungi were observed among treatments. Overall, our study suggests that supplementation with $10^6CFU/ml$ C. saccharobutylicum has the potential to improve ruminal fermentation through increased concentrations of butyrate and total volatile fatty acid, and enhanced population of butyrate-producing bacteria and cellulolytic bacteria F. succinogenes.

• 한국유기농업학회지
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• 제26권4호
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• pp.775-787
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• 2018

본 연구는 반추동물의 메탄 감소에 효과가 있는 합성첨가제를 대체 할 수 있는 천연첨가제를 찾고자 연구를 실시하였다. 첨가제인 MRA-1(파), MRA-2 (SLS), MRA-3 (SDS), MRA-4(파+탄닌산)를 만들어 발효시간대별(3, 6, 9, 12, 24 및 48 h) in vitro 시험을 실시하였다. pH는 발효시간동안 적정범위였으며, 건물소화율은 모든 발효시간대별 모든 처리구에서 대조구와 유의적(P>0.05)인 차이를 보이지 않았고, 미생물성장량에도 부정적인 영향을 미치지 않았다. 메탄 발생량은 발효 24시간대 MRA-1구를 제외한 나머지 처리구에서 대조구에 비해 유의적(P<0.05)으로 낮게 측정되었으며, 특히 이산화탄소 발생량은 MRA-4 첨가구에서 발효 9, 24, 48시간대에서 유의적(P<0.05)으로 낮았다. 메탄생성량 감소에 영향이 있는 프로피온산 함량은 발효 24시간대 MRA-4구에서 대조구에 비해 유의적(P<0.05)으로 높았다. Ciliate-associated methanogens은 발효 24시간대 MRA-1, MRA-3 및 MRA-4구에서 대조구에 비해 유의적(P<0.05)으로 낮게 측정되었다. 따라서 파와 탄닌산은 반추위 내 메탄 저감 효과가 있는 합성첨가제를 대체 할 수 있어 반추동물용 천연 메탄 저감제로서의 활용 가능성이 있을 것으로 사료된다.

• 한국환경과학회지
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• 제28권6호
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• pp.527-533
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• 2019

The aim of present study was to investigate the effect of three types of Chestnut Meals (CM) on chemical composition and rumen fermentation characteristics of the fermented diet. The inoculants consisted of Lactobacillus acidophilus, Bacillus subtilis, and Sacaromyces cerevisiae and were applied to three different types of CM; Whole Chestnut (WC), endodermis (EN), and kernel (KE). All types of CMs were ensiled at $39^{\circ}C$ for 0, 1, 2, 4, or 6 days. After ensiling, the fermented CMs were sub-sampled for laboratory assays. On day six of fermentation, counts of the lactic acid-producing Bacillus subtilis, and yeast were higher (P<0.05) in WC than in the other CM types. On day four, KE had higher (P<0.05) crude protein content but lower (P<0.05) neutral detergent fiber and acid detergent fiber contents than the other treatments. In terms of rumen digestibility, KE had the highest (P<0.05) in vitro digestibility of dry matter (IVDMD), neutral detergent fiber digestibility (IVNDFD), total volatile fatty acid (VFA), propionate, butyrate concentrations, and total gas volume, as well as the lowest (P<0.05) acetate concentration. On the other hand, EN had the highest (P<0.05) pH and ammonia-N concentration in the rumen. In the rumen, even though WC application produced the highest microbial count and fermentation characteristics, it did not have a beneficial effect on rumen digestibility. Therefore, this study concluded that application of KE could be recommended due to the observed improvements in IVDMD and IVNDFD.

• Animal Bioscience
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• 제34권1호
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• pp.74-84
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• 2021

Objective: Feed additives that modify rumen fermentation can be used to prevent metabolic disturbances such as acidosis and optimize beef cattle production. The study evaluated the effects of liquid and powdered forms of polyclonal antibody preparation (PAP) against Streptococcus bovis and Fusobacterium necrophorum on rumen fermentation parameters in ruminally cannulated non-lactating dairy cows that were adapted or unadapted to a high concentrate diet. Methods: A double 3×3 Latin square design was used with three PAP treatments (control, powdered, and liquid PAP) and two adaptation protocols (adapted, unadapted; applied to the square). Adapted animals were transitioned for 2 weeks from an all-forage to an 80% concentrate diet, while unadapted animals were switched abruptly. Results: Interactions between sampling time and adaptation were observed; 12 h after feeding, the adapted group had lower ruminal pH and greater total short chain fatty acid concentrations than the unadapted group, while the opposite was observed after 24 h. Acetate:propionate ratio, molar proportion of butyrate and ammonia nitrogen concentration were generally greater in adapted than unadapted cattle up to 36 h after feeding. Adaptation promoted 3.5 times the number of Entodinium protozoa but copy numbers of Streptococcus bovis and Fibrobacter succinogens genes in rumen fluid were not affected. However, neither liquid nor powdered forms of PAP altered rumen acidosis variables in adapted or unadapted animals. Conclusion: Adaptation of cattle to highly fermentable carbohydrate diets promoted a more stable ruminal environment, but PAP was not effective in this study in which no animal experienced acute or sub-acute rumen acidosis.

• Journal of Animal Science and Technology
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• 제62권6호
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• pp.801-811
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• 2020

The main objective of this in vitro study was to evaluate red ginseng byproduct (RGP) as a protein resource and its effects on rumen fermentation characteristics, microflora, CO2, and CH4 production in ruminants. Four treatments for in vitro fermentation using buffered rumen fluid over a 48 h incubation period were used: 1, RGP; 2, corn gluten feed (CGF); 3, wheat gluten (WG); and 4, corn germ meal. In vitro dry matter digestibility (IVDMD), in vitro neutral detergent fiber digestibility (IVNDFD), in vitro crude protein digestibility (IVCPD), volatile fatty acids, pH, and ammonia nitrogen (NH3-N) were estimated after 48 h incubation. Gas production was investigated after 3, 6, 12, 24, 36 and 48 h. The CO2 and CH4 were evaluated after 12, 24, 36, and 48 h. A significant difference in total gas production and CO2 emissions was observed (p < 0.01) at all incubation times. CH4 production in RGP were higher (p < 0.05) than that in other treatments but a higher CH4 portion in the total gas production was observed in WG (p < 0.05) at 48 h incubation. The IVDMD, IVNDFD, and IVCPD of RGP was lower than those of other conventional ingredients (p < 0.01). The RGP had the lowest NH3-N value among the treatments (p < 0.01). The RGP also had the lowest total VFA concentration (p < 0.01), but presented the highest acetate proportion and acetate to propionate ratio among the treatments (both, p < 0.01). The abundance of Prevotella ruminicola was higher in RGP than in WG (p < 0.01), whereas RGP has lower methanogenic archaea (p < 0.01). In conclusion, based on the nutritive value, IVDMD, low NH3-N, and decreased methanogenic archaea, RGP inclusion as a protein source in ruminant diets can be an option in replacing conventional feed sources.