• 한국미생물·생명공학회지
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• 제25권1호
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• pp.68-74
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• 1997

The conversion of D-sorbitol to L-sorbose by Gluconobater suboxydans was analyzed, and continuous production of L-sorbose was carried out in immobilized cell reactors. L-Sorbose production by high densities of resting cells was more effective than by conventional batch fermentations. Sorbitol dehydrogenase, an enzyme converting D-sorbitol to L-sorbose, did not suffer from substrate inhibition, but from product inhibition. When L-sorbose production was carried out with Ca-alginate-immobilized cells, about 60 g/l of L-sorbose was obtained. On the other hand, when the corn steep liquor (CSL) concentration of medium was reduced to 0.08%, 80 g/l of L-sorbose was obtained. Outgrowth inside the immobilized carriers was thought to block the pores of the carriers so that substrate could not easily diffuse through the carriers. Continuous production of L-sorbose was well accomplished in a bubble column reactor, and 6. 5 g/l.h of productivity and 81.2% of yield were obtained at a substrate feeding rate of 0.08h$^{-1}$ under the optimum conditions with carrier volume of 55% and aeration rate of 3 vvm.

• Nutrition Research and Practice
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• 제2권4호
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• pp.195-199
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• 2008

Alcoholism has been associated with folate deficiency in humans and laboratory animals. Previous study showed that ethanol feeding reduces the dehydrogenase and hydrolase activity of 10-formyltetrahydrofolate dehydrogenase (FDH) in rat liver. Hepatic ethanol metabolism generates acetaldehyde and acetate. The mechanisms by which ethanol and its metabolites produce toxicity within the liver cells are unknown. We purified FDH from rat liver and investigated the effect of ethanol, acetaldehyde and acetate on the enzyme in vitro. Hepatic FDH activity was not reduced by ethanol or acetate directly. However, acetaldehyde was observed to reduce the dehydrogenase activity of FDH in a dose- and time-dependent manner with an apparent $IC_{50}$ of 4 mM, while the hydrolase activity of FDH was not affected by acetaldehyde in vitro. These results suggest that the inhibition of hepatic FDH dehydrogenase activity induced by acetadehyde may play a role in ethanol toxicity.

• Journal of Animal Science and Technology
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• 제52권4호
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• pp.281-286
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• 2010

본 연구에서는 초유를 장기간 보관하는 동시에 유산균의 함량을 증진시킨 발효초유를 Holstein 송아지의 성장 및 설사발생에 미치는 효과를 조사하였다. 발효초유를 제조하기에 적합한 균주를 선택하기 위한 실험으로 L. rhamnosus와 E. faecium을 혼합하여 사용한 경우 풍미가 좋았고 대장균군의 억제가 우수하였으며 유산균의 증식도 활발하여 이 두 균을 혼합하여 사용하는 것이 초유발효에 적합하다고 판단되었다. 송아지 사양 실험 결과로서 분변 중의 대장균과 젖산균수의 조사 결과 대장균은 발효초유 20% 첨가구에서 시간 경과 후 가장 많이 감소하는 경향을 보였으며 분내 유산균은 급여 28일째 대조구에 비하여 20% 급여수준에서 균수가 유의하게 증가하였다. 발효초유 급여 후 체중변화는 28일 후 20% 첨가구의 경우 1.4 kg (7.8%)으로 가장 높은 증체효과를 보였다. 기간별 증체효과를 살펴보면 20% 첨가구의 경우 0~14일은 0.41 kg으로 각각의 실험구 중 가장 증체량이 낮게 나타났고 14~28일의 증체량은 0.87 kg으로 이 기간 중에는 일당증체량이 가장 높게 나타나 장기 급여가 효과가 있을 것으로 추정되었다. 그러나 발효초유 급여 수준에 따른 설사 지속 일수는 무첨가구는 2.7일, 5% 첨가구 2.4일, 10% 첨가구 4일, 20% 첨가구는 2.4일로서 무첨가구, 5% 첨가구, 20% 첨가구는 3일 이내에 설사가 멈추었으나 10% 첨가구의 경우 3일 이상 지속되어 발효 초유첨가에 따른 설사 방지효과는 분명히 나타나지 않는 것으로 보였다. 이상의 결과에서 발효초유 첨가가 증체에 미치는 영향은 14일 이후 발효초유첨가 수준이 높을수록 또는 급여기간이 길수록 증체효과에 영향을 끼친다고 볼 수 있고 설사방지 효과의 경우 발효초유 첨가 수준에 의해서는 별 영향을 미치지 못하는 것을 알 수 있었다.

• KSBB Journal
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• 제6권1호
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• pp.35-43
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• 1991

The production of poly-$\beta$-hydroxybutyrate(PHB) from methanol by batch and fed-batch cultivations of Methylobacterium sp. GL-10 was studied. PHB accumulation was stimulated by the nutrients deficiency including, NH4+, SO42-, and K+. The nitrogen deficiency was the most critical factor for PHB accumulation. In batch cultivation, the maximum cell concentration and PHB content were 1.86g/l and 0.62g/l, respectively, with 1.0%(v/v) of methanol and 0.5g/1 of ammonium sulfate. The mass doubling time of Methylobacterum sp. GL-10 was in the range of 4-5 hrs. The cell growth and PHB accumulation were severely inhibited at the methanol concentration over than 2% (v/v). To overcome methanol Inhibition, constant feeding and intermittent feedillg fed-batch cultivations were adopted, using C/N molar ratio as a control factor. In constant feeding fed-batch process, cell concentration was increased up to 2.67g/1, and PHB yield was enhanced from 0.33 of batch culture to 0.53. The relatively low cell concentration was caused by methanol accumulated in culture broth at late growth phase. To prevent methanol accumulation and to maximize PHB production, DO-state intermittent fed-batch cultivation was attempted. The cell and PHB concentration was reached up to 4.55g/1 and 1.80g/1, respectively. It was possible to maintain methanol concentration low and also to feed nutrient of desired C/N molar ratio.

• 농약과학회지
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• 제17권1호
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• pp.33-40
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• 2013

온실가루이와 담배가루이의 살충과 행동에 미치는 pyrifluquinazon의 효과를 조사하였다. Pyrifluquinazon은 가루이류의 성충에 대해 50 ppm부터 12.5 ppm까지 90% 이상의 살충활성을 나타내었으나, 알과 약충에는 효과가 없었다. 뿌리와 잎을 통한 침투이행효과는 없었으나, 잔효성 검정에서 처리 후 5일차까지 90% 이상의 살충활성을 나타내었고, 90% 이상의 방제효과를 나타내었다. 접촉독성과 섭식독성에 의한 가루이류의 행동과 발현속도를 조사한 결과, 접촉 1시간 이후부터 가루이류는 바닥에 떨어져 심한 날개경련과 마비를 일으키는 증상을 나타내었으며, 섭식 3시간 이후부터 유사한 증상을 나타내었다. 한편, 선택시험에서 가루이류는 방사 1시간 이후부터 기피행동을 나타내었다. 따라서 pyrifluquinazon는 온실가루이와 담배가루이에 속효적으로 작용하고 날개 경련과 마비증상을 유발하여 식물체로부터 바닥으로 떨어져 아사하는 효과를 나타내지만, 직접적인 섭식억제효과는 없는 것으로 여겨졌다.

• Journal of Nutrition and Health
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• 제29권6호
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• pp.608-614
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• 1996

This study was performed to investigate the influcence of mugwort on the duodenal ulcer induced by cysteamine administration in rats. Five groups of rats were fed each experimental diet containing 0%, 5%, 15%, 30% of mugwork powder for 10 weeks. Duodenal ulcer was induced by cysteamine injection (400mg/100g body weight) after 10 weeks of feeding experimental diets (C-0, C-5, C-15, C-30). Control animal that fed 0% mugwork powder added diet were injected saline (S-0) to compare with cysteamine injected groups. When the duodenal ulcer induced by cysteamine-HCI administration, all animals in the C-0 group formed erosion and perforating ulcer was found in 44% of animals. Higher the added mugwork ratio, more inhibited of the duodenal ulcer induced by cysteamine administration (C-5, C-15). But when the ratio of added mugwort is 30%, the inhibition effect disappeared (C-30). The alkaline phospatase activities were lower at the duodenal mucosa and small intestinal mucosa in the cysteamine treated groups(p<0.05). The acid phophatase activities were higher at the stomach, small intestine and large intestine of the cysteamine treated groups. But in mugwort added diet group, the changes of enzyme activites were lessended. The maltast activities were lower at the duodental mucosa and small intestinal mucosa of cysteamine treated groups. But in mugwort added diet group, maltase activites were recovered.

• Journal of Ginseng Research
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• 제19권3호
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• pp.206-211
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• 1995

This study was investigated to find the effects of petroleum ether extract (Lipophilic fraction) from Korean red ginseng on platelet aggregation and thrombin time of the plasma in two groups of the experimental rats. One group of rats were fed with 15% corn oil (15%kg-diet) containing a number of 18 : 2 (linoleic acid) or 15% beef-tallow (15%/kg-diet) containing saturated fatty acids for 3 weeks, and were followed by feeding the petroleum ether extract (25 mg/kg-diet) for 3 weeks. The other group of rats (control group) were fed with 15% corn oil or 15% beef-tallow for 6 weeks. The platelet aggregation induced by thrombin and collagen was significantly inhibited and the thrombin time was prolonged in the 15% corn oil plus petroleum ether extract administrated group than in the 15% corn oil administrated group. And the same results were shown in the 15% beef-tallow plus petroleum ether extract administrated group. These results suggest that the petroleum ether extract from Korean red ginseng may have the beneficial effects on the inhibition of the platelet aggregation and the inhibition of blood coagulation induced by dietary fats.

• 대한한방소아과학회지
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• 제38권1호
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• pp.37-45
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• 2024

Objectives The aim of this study was to determine the inhibitory effects of Bangpungtongsungsan extract (BTS) on fat accumulation in high-fat diet-induced young obese mice. Methods The extract was administered to 3-week-old C57BL/6 male mice fed with a high-fat diet. The experimental groups were divided into a control group (Ctrl), high-fat diet group (HFDF), and BTS treated group after high fat diet feeding (BTST), with 10 mice assigned to each group. Lipid synthesis was observed to confirm the inhibition of fat synthesis. Changes in body weight, body fat percentage, and total cholesterol in the blood were observed to confirm weight control. Peroxisome proliferator-activated receptor gamma (PPAR-γ) and sterol regulatory element-binding protein (SREBP)-1 positivity was observed to confirm the inhibition of fat accumulation in liver tissue. Results Bangpungtongsungsan significantly inhibited lipid synthesis. Changes in body weight, body fat percentage, and total cholesterol in the blood were significantly lower in BTST rats than in HFDF rats. PPAR-γ and SREBP-1 positivity were significantly lower in BTST rats compared to HFDF rats. Conclusions This study confirms the potential of BTST to inhibit fat accumulation in obesity.

• KSBB Journal
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• 제8권2호
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• pp.164-171
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• 1993

Methylomonas mucosa를 이용하여 세포외 다당류의 생산을 알아보았다. 본 미생물은 성장을 위해 메탄올을 탄소원으로 이용하여 세포외 다당류를 생산한다. 효과적인 발효 공정 시스템의 개발올 위해 회 분식, 유가식, 연속식 배양을 수행하여 각각의 당류 에 대한 생산성을 알아보았다. 플라스크 배양에서 메탄올이 약 1 % (v/v) 이상에서 다당류의 생산과 세포의 성장은 저해되었다. 1% (v/v)에서 최대 비성장속도를 나타내었고 C/N 비율이 높을수록 다당류의 생산은 많았다. 다당류의 생산에 $Mg^{2+}$ 이온 농도가 크게 영향을 줌을 확인할 수있었다. 유가식 배양에서는 다당류의 농도가 회분식에 비 해 4배 이상 높았으나 수율은 오히려 감소하였다. 연속주입을 통한 유가식 배양은 간헐적 주업방법보다 생산성이 높았다. 이는 간헐적 주입에서 나타날 수 있는 메탄올에 의한 제한이나 저해가 없었기 때 문으로 보여진다. 연속조엽은 산소 제한을 피하기 위해 순수산소를 공급하였다. 희석률이 O.21h-1까지 증가하여도 수융 과 생산성은 증가하였다. 생산된 다당류 용액의 점도는 다당류의 증가에 따라 지수적으로 증가하였다.

• KSBB Journal
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• 제5권3호
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• pp.269-277
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• 1990

메탄올이용균인 Methylobacillus sp. SKI의 균체생산효율을 증대시킬 목적으로 마이크로컴퓨터 제어 배양기를 이용해 고농도 유가배양을 수행하였다. 배양액의 초기 메탄올농도를 1.0%(v/v)로 하여 회분배양할 경우 배양 13시간만에 2.07g/l의 균체농도에 도달하였다. 공기 공급에 의한 유가배양에서 최대교반속도 1200rpm, 최대 공기유량 5.0$\ell$/min의 조건으로 배양시 약 15시간만에 13.7$\ell$/ldml 균체농도에 도달하였다. 산소공급에 의한 유가배양에서 최대교반속도 1200rpm, 공기유량 1.0$\ell$min, 최대산소유량 5.0$\ell$/min의 조건으로 배양시 17시간만에 45.3g/l의 균체농도에 도달하였다. 균의 대수 증식기를 공기공급에 의한 유가 배양으로 회분배양에 비해 약 3시간, 산소공급에 의한 유가배양으로 회분배야에비해 약 3시간, 산소공급에 의한 유가배양으로 회분배양에 비해 약 4시간 더 연장할 수 있었다. 즉, 유가배양로 단시간에 높은 농도의 균체를 얻은 것은 feedback제어에 의해 메탄올을 저해농도 이하로 유지시키면서 용존산소를 한계농도 이상으로 제어함으로써 균의 대수적 증식으로 연장시킨 결과이다. 산소공급에 의한 유가배양중 균체농도 27.6g/l에서 미량원소성분이 결핍되었고, 42.8g/l에서 $Mg^2^+$성분이 결핍되었으므로 배양중에 추가공급되었다.