• 펄프종이기술
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• 제31권5호
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• pp.1-11
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• 1999

Wood components, cellulose and lignin, are degraded simultaneously and the general outline for the complementary character of carbohydrates and lignin decomposition as well as the existence of enzymatic systems combining these processes is still valid. The degradatiion of free cellulose or hemicellulose into monosaccharides has long been known to be relatively simple, but the mechanism of lignin degradatiion wasn ot solved very clearly yet. Anyway the biodegradation of woold constituents is understood at present as an enzymatic process. Kigninolytic activity has been correlated with lignin and manganese peroxidases. At present the attention is paid to laccase. Laccase oxidizes lignin molecule to phenoxy radicals and quinones . This oxidation can lead to the cleavageo f C-C or C-O bonds in the lignin phenyl-propane subunits, resulting either in degradation of both side chains and aromatic rings, or in demethylation processes. The role of laccase lies in the "activation" of some low molecular weight mediators and radicals produced by fungal cultures. Such activated factors produced also in cooperation with other enzymes are probably exported to the wood environment where they work in degradation processes as the ' enzyme messengers." It is worth mentioning that only fungi possessing laccase show demethylating activity. Thus demethylation, the process important for ligninolysis, is probably caused exclusively by laccase. Under natural conditions laccase seems to work with other fungal enzymes , mediators and mediating radicals. It has shown the possibility of direct Bjrkman lignin depolymerization by cooperative activity of laccase and glucose oxidase.

• 대한한방내과학회지
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• 제25권2호
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• pp.277-287
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• 2004

Objective : Diabetes is a disease in which the body does not produce or properly use insulin. Etiological studies of diabetes and its complications showed that oxidative stress might playa major role. Therefore, many efforts have been made to regulate oxygen free radicals for treating diabetes and its complications. Because Jindangwon has been known to be effective in treatment of diabetes, the methanol extract of Jindangwon was tested for its effectiveness in reducing the oxidative stress induced by Streptozotocin. Methods : Jindangwon was washed, dried in the shade and crushed. The crushed Jindangwon was extracted 3 times, each time with 3 volumes of methyl alcohol at $60^{\circ}C$ for 24 hours. The extract was filtered and evaporated under reduced pressure using a rotary evaporator to yield 30.6 g. Jindangwon extract was oral-administered to the diabetic rats induced by streptozotocin 50 mg per 1 kg of body weight for 15 days. The efficacy of the Jindangwon extract was examined with regard to the enzymatic pathways involved in the oxygen free radical production and the glutathione balance. Results : he effects of the methanol extract of Jindangwon in streptozotocin-induced diabetics rats with regard to body weight, blood glucose level, hepatic lipid peroxide level, hepatic xanthine oxidase activity and type conversion rate, hepatic glutathione level, hepatic glutathione peroxidase activity, hepatic glutathione reductase activity, hepatic aldose reductase activity, and hepatic sorbitol dehydrogenase activity were favorable enough to suggest that it is a cure for diabetes and its complications. Conclusions :These results support Jindangwon as an effective reducing agent for oxidative stress in the tissues and organs by regulating the production of oxygen free radicals. Jindangwon, in particular, shows promising results for its use as a cure, or preventative medicine for diabetes and its complications by reducing oxidative stress in beta-cells of the pancreas.

• 대한한의학방제학회지
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• 제10권2호
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• pp.159-188
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• 2002

The purpose of this study was to reseach the effect of Daehwanggamchoeumja(大黃甘草飮子) and its component groups on diabetes, free radicals, and antioxidants system in Alloxan-induced diabetic rats. The experimental group was divided into three groups: Daehwanggamchoeumja(DG), and its components groups, Gamdutang (Gamcho&Daedu; DG-I) and Daehwanggamchotang(DG-2). The results were obtained as follows: 1. In the study of effect on diabetic metabolic dysfunction(Glucose, Triglyceride, Total Cholesterol, HDL Cholesterol, Total Protein, Albumin, Creatine, BUN), only DG has a significant effect. 2. In the study on free radical scavenging effect in vitro(the suppressing effect on peroxidation of linoleic acid on concentration, the scavenging effect of DPPH radical, inhibitory effect of superoxide in xanthine-xanthine oxidase system, inhibitory effect on lipid peroxidation reaction by hydroxy radical in $H_2O_2Fe^{2-}$system, and the effect on Nitrate reductase activity), DG and DG-2 have more effect than DG-l relatively. 3. In the study on antioxidants system in vivo(The level of serum LPO, The level of hepatic LPO, Catalase, GSH, GST), only DG has a significant effect. These results suggest that Daehwanggamchoeumja(大黃甘草飮子) has an effect on diabetes, peroxidative damage by free radical, so it seems to be useful to prevent and treat diabetes. The mechanisms of these are supposed to be involved in antioxidant and three drugs' cooperative synergy effect.

• 생명과학회지
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• 제29권11호
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• pp.1179-1191
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• 2019

암세포는 epithelial mesenchymal transition (EMT)를 통해 tumor invasion과 metastasis가 일어나며, 또한 정상세포와 다른 oncogenic metabolic phenotypes 획득 즉, glycolytic switch 등이 암 발생과 진행에 깊이 연관되어 있음이 잘 알려져 있다. High-mobility group box 1 (HMGB1)은 chromatin-associated nuclear protein으로 알려져 있으나, dying cells 또는 immune cells로부터 방출되기도 한다. 방출된 HMGB1은 damage-associated molecular pattern (DAMP)로서 작용하여 EMT 및 invasion, metastasis를 유도함으로서 tumor progression에 기여한다고 알려졌다. 본 연구에서 HMGB1에 의해 EMT와 glycolytic switch 유도되며, 이 과정은 Snail 의존적임을 확인하였다. 또한 HMGB1/Snail cascade는 COX subunits인 COXVIIa와 COXVIIc의 발현 억제를 통해 mitochondrial repression과 cytochrome c oxidase (COX) inhibition을 유도하였다. HMGB1은 Snail를 통해 glycolytic switch의 주요 효소인 hexokinase 2 (HK2), phosphofructokinase-2/fructose-2,6-bisphosphatase 2 (PFKFB2), phosphoglycerate mutase 1 (PGAM1)의 발현을 증가시켰다. 이들 효소는 glycolytic switch에 중요하게 관여하는 것으로 알려져 있다. 이들 해당과정의 효소들을 knockdown한 결과 HMGB1에 의한 EMT를 억제함으로써 glycolysis와 HMGB1-induced EMT가 밀접하게 연관되어 있을 제시하였다. 이상의 연구 결과들은 HMGB1/Snail cascade가 EMT 및 glycolytic switch, mitochondrial repression에 중요하게 작용할 것임을 시사한다.

• 한국균학회지
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• 제51권1호
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• pp.39-49
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• 2023

남덕유산 월성계곡과 대전광역시 진참천 등지로부터 분리한 야생효모들 중 국내 미기록 야생효모들을선별한후, 이들의균학적특성과효소활성및생리활성등을조사하였다. 이들야생효모들중Candida sorboxylosa WSC25-4 (NNIBRFG47336), Arxula adeninivorans WSC6-3 (NNIBRFG47335), Farysizyma taiwaniana JRC6-2 (NNIBRFG47339), Saturnispora dispora JTS19-1 (NNIBRFG47334), Vanderwaltozyma polyspora JJCH5-3 (NNIBRFG47337)과Vanrija fragicola SW-9 (NNIBRFG47338) 등 6균주들을 국내 미기록 야생효모들로 최종 선별하였다. 이들 균주들은 대부분 구형으로 출아에 의해 영양증식을 하였고, 모두 자낭포자와 의균사들을 형성하지 않았다. V. polyspora JJCH5-3외 5균주들이 YPD, YM, PD등의 배지에서 잘 생육하였고, A. adeninivorans WSC6-3와S. dispora JTS19-1 균주들은 40% 포도당을함유한 YPD 배지에서잘생육하는내당성을보였으며, V. fragicola SW-9 균주는 5% NaCl을 함유한 YPD배지에서 생육하는 호염성 효모로 확인되었다. 국내 미기록 야생효모들의 배양 상등액들 중A. adeninivorans WSC6-3과F. taiwaniana JRC6-2, V. fragicola SW-9 등의 glucoamylase 활성이 각각 58.0, 59.0, 59.0% 로 비교적 높았고, C. sorboxylosa WSC25-4 균주는 알칼리성 단백질분해효소 활성이 높아 세재 산업에 유용할 것으로 사료된다. 또한, 미기록 효모들의 모든배양상등액은항산화활성과 SOD-유사활성이 70-98%로매우높았고, S. dispora JTS19-1과V. fragicola SW-9의항통풍성잔틴산화효소저해활성도각각 70%와 80%로높았다.

• Journal of Microbiology and Biotechnology
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• 제11권6호
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• pp.915-921
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• 2001

Phytase improves the bioavailability of phytate phosphorus in plant foods to humans and animals, and reduces the phosphorus pollution of animal waste. In order to express a high level of fungal phytase in Saccharomyces cerevisiae, various expression vectors were constructed with different combinations of promoters, translation enhancers, signal peptides, and terminator. Three different promoters fused to the phytase gene (phyA) from Aspergillus niger were tested: a galactokinase (GAL1) promoter, glyceraldehyde-3-phosphate dehydrogenase (GPD) promoter, and yeast hybrid ADH2-GPD promoter consisting of alcohol dehydrogenase II (ADH2) and a GPD promoter. The signal peptides of phytase, glucose oxidase (GO), and rice amylase 1A(RAmy1A) were included. Plus, the translation enhancers of the ${\Omega}$ sequence and UTR70 from the tobacco mosaic virus (TMV) and spinach, respectively, were also tested. Among the recombinant vectors, pGphyA06 containing the GPD promoter, the ${\Omega}$ sequence, RAmy1A, and GAL7 terminator expressed the highest phytase activity in a culture filtrate, which was estimated at 20 IU/ml. An intracellular localization of the expressed phytase activity in a culture filtrate, which was estimated at 20 IU/ml. An intracellular localization of the expressed phytase was also performed by inserting an endoplasmic reticulum (ER) retention signal, KDEL sequence, into the C-terminus of the phytase within the vector pHphyA-6. It appeared that the KDEL sequence directed most of the early expression of phytase into the intracellular compartment yet more than $60\%$ of the total phytase activity was still retained within the cell even after the prolonged (>3 days) incubation of the transformant. However, the intracellular enzyme activity of the transformant without a KDEL sequence was as high as that of the extracellular one, thereby strongly suggesting that the secretion of phytase in S. cerevisiae appeared to be the rate-limiting step for the expression of a large amount of extracellular recombinant phytase, when compared with other yeasts.

• Toxicological Research
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• 제15권1호
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• pp.79-87
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• 1999

To know the stress response and antioxidative effect of sulfur containing compounds, we observed the expression of the stress protein (heat shock protein; inducible protein) from mouse tissues and evaluated the protective effects to hydroxyl radical in mouse brain cell culture. Cysteine, methionine or sodium sulfide was fed by oral administration of 1 ml/per 6hr/three times with 1 mM, 2mM or 3mM to mouse, respectively. After that, the stress proteins were extracted from mouse tissues and analyzed the features of expression. The stress proteins by sulfur containing compounds were showed different aspects in the kinds and concentrations of their compounds, and in the tissues of mouse. In the liver, the stress proteins were appeared at different time on the concentration of sulfur containing compounds and had less than 20 KDa as small molecules. In general, the molecular weights of stress protein in liver, the stress proteins were appeared at different time on the concentration of sulfur containing compounds and had less than 20 KDa as small molecules. In general, the molecular weights of stress protein in the spleen were evaluated from 32KDa to 50KDA, and the induced times were relatively late at high concentration of cysteine, early at low concentration of methionine or sodium sulfide. The stress proteins in mouse muscle were detected mostly between 24hr after treatment of sulfur containing compounds. Their molecular weights were 15~24KDa. In the antioxidative effects of sulfur containing compounds to hydroxyl radical, cell viabilities were measured by 63.2% at 10 $\mu\textrm{M}$, 65.5% at 50 $\mu\textrm{M}$, 68.6% at 100 $\mu\textrm{M}$, 78.3% at 150 $\mu\textrm{M}$, or 83.0% at 200 $\mu\textrm{M}$ of cysteine, respectively. At addition of methionine, the cell viabilities were assessed as 58.1% at 10 $\mu\textrm{M}$, 62.8% at 50 $\mu\textrm{M}$, 75.7% at 100 $\mu\textrm{M}$, 78.6% at 150 $\mu\textrm{M}$, and 79.2% at 200 $\mu\textrm{M}$ after 4hrs exposure with 20mU/ml glucose oxidase (GO) system, while the numbers of live cells to hydroxyl radicals in treatment of sodium sulfide were showed 48.6% at 10 $\mu\textrm{M}$, 54.8% at 100 $\mu\textrm{M}$, 51.8% at 150 $\mu\textrm{M}$, and 51.6% at 200 $\mu\textrm{M}$ in the neuronal cells. In the inhibitory effects on the proliferation of tumor cells, percentages of dead cells of the CT-26 or HeLa cell were generally less than 30% even 48hr after addition of sulfur containing compounds. Conclusively, the results of these experiments indicate that stress protein by sulfur containing compounds can be used as physiological indicator for animal nutrition and for environment, and also that cysteine and methionine can play critical roles as an antioxidant.

• 미생물학회지
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• 제34권4호
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• pp.212-218
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• 1998

세포외 다당류를 분비하는 새로운 methylotrophic bacteria를 분리하여 세균의 특징과 그 세균이 생산하는 세포외 다당류의 물리 화학적 특성을 조사하였다. 분리균주는 그람음성의 간균으로 편모가 없는 비운동성 세균이며, DNA의 G+C 함량은 53-56%이었고, plasmid를 가지고 있지 않았다. 메탄올과 메틸아민만을 기질로 이용하였으며, 탄소동화경로로는 ribulose monophosphate pathway를 이용하는 절대 methylotrophic bacteria이었다. 성장을 위한 최적온도와 pH는 각각 $35^{\circ}C$와 6.5이었고, 0.5%(v/v)의 메탄올이 포함된 배지에서 가장 빨리 성장하였다(세대시간=2.4시간). 분리균주는 절대 호기성 세균으로 질소원과 산소가 결핍된 조건에서 다량의 세포외 다당류를 분비하였다. 다당류 생산을 위한 최적온도와 pH는 각각 $30^{\circ}C$와 6.5이었고, 1.0%(v/v)의 메탄올이 포함된 배지에서 배지내의 탄소 대질소비가 57.4일 때 가장 많이 생산되었다. 정제된 다당류는 포도당과 galactose로 이루어져 있었다. 에탄올 처리전의 다당류는 낮은 pH에서 더 높은 점도를 보였고, 온도와 염류농도의 변화에도 비교적 안정하였다. 에탄올 처리후의 다당류는 xanthan gum보다 높은 점도를 나타내었고, pH, 온도, 염류농도의 변화에 대해 점도변화가 크지 않았다. 냉동건조된 다당류를 전자현미경을 이용하여 관찰하였을 때, 에탄올 처리전의 다당류는 얇은 막이 겹친 구조를 하고 있었고, 에탄올 처리후의 다당류는 굵은 섬유상의 모습을 띠고 있었다.

• Applied Biological Chemistry
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• 제13권1호
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• pp.1-27
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• 1970

황색종 잎담배의 인공발효숙성은 효모처리에 의한 인공발효, 단순한 인공숙성, 2년 저장숙성 및 미처리구로 나누어 미생물학, 물리학, 화학, 생화학적으로 그 변화과정을 종합적으로 연구하여 다음과 같은 결과를 얻었다. 1. 한국산 잎담배 Y.S.A의 발호숙성을 촉진시키는 최적 조건으로서는 및 담배를 온도 $40^{\circ}C$평형함수율 18%, 관계습도 74%에 놓아두는 것이 잎담배의 모든 품질적 특성에 가장 양호한 결과를 주는 것임을 알게되었다. 2. 잎담배를 $40^{\circ}C$의 숙성온도 및 74%의 상대습도에서 효모를 첨가하여 약 20일 내외에서 숙성을 촉진시켜 숙성시키면 잎담배의 여러가지 물리적 및 화학적 특성이 1년 및 2년 저장숙성시킨 것과 비슷하게 됨을 알게 되었음으로 그 실용적 효과를 입증할 수 있었다. 3. 온도 $40^{\circ}C$와 평형함수율 18%의 숙성조건하에서 잎담배에 효모를 첨가하여 또는 단순히 조기숙성시켰을 때 잎담배는 그 숙성에 필요한 물리화학적 특성은 약 20일만에 얻을 수 있다는 것을 알게되었다. 4, 본 실험에서 잎담배의 발효숙성기간중 미생물의 동태는 효모와 세균은 15일까지 증가하였다가 감소하였고 곰팡이류는 끝까지 계속 증가하였다. 5, 효모구 및 속성구 잎담배의 이화학성은 발효숙성이 $15{\sim}20$일 진행함에 따라 pH는 저하하였고 팽승성과 연소성이 양호하여 졌고 자극순도, 명도주재파장등 색택에 관련되는 물리성이 2년저장 잎담배와 비등하여졌다. 또 총환원성물질, 전당, 전환원당, 알카로이드량은 감소하였고 유기산, ether 추출물은 증가, 전질소 및 단백질량, 조섬유, 회분등은 별 변화가 없었다. 6. 효모 및 속성구의 잎담배는 발효숙성이 15-30일 진행되는 동안 그 개개의 화학성분이 다음과 같이 변화하였다. 즉, 시일이 경과함에 따라 당 류-sucrose, rhamnose, glucose 색소류-chlorophyll, carotenes, xanthophyll, violaxanthine polyphenols-rutin, chlorogenic 및 caffeic acid 유기산-iso?tutylic, crotonic, capronic, galacturonic,tartaric, succinic, citric acid 알카로이드-nicotine,nornicotine등 화합물은 감소하였다. 한편 시일이 경과함에 따라 당 류-fructose, maltose, raffnose 아미노산-proline, cystine, 유 기 산-formic, acetic, propionic, malic, oxalic,malonic, α-ketoglutaric, fumaric, glutaric acid 등 화합물은 증가하였다. 7. 잎담배 발효숙성중 생화학적 특성의 변화는 다음과 같았다. 즉, 30일간의 발효숙성기간중 산소흡수량은 점차 감소하였으며, ${\alpha}-amylase$ ${\beta}-amylase$}활성도는 점차 약하여 졌으나 catalase, invertase는 그 활성도가 일단 숙성중기에 높아졌다가 낮아졌다.

• Applied Biological Chemistry
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• 제47권1호
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• pp.27-32
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• 2004

가금티프스는 닭, 오리, 칠면조, 꿩 등 가금류에 Salmonella gallinarum이 원인균이 되어 발병하는 질병이다. 본 연구는 가금티프스를 방제하기 위한 생균제 개발을 위한 기초조사의 목적으로 가금티프스 원인균인 5. gallinarum 의 생육을 저해시킬 수 있는 길항균을 야생꿩에서 분리, 선발했다. 최종적으로 3종의 우수 길항균주를 선발하였으며 선발, 분리된 길항균을 동정한 결과 Ll9, L33균주는 similarity가 100%인 Sphinromonas sanguis로 동정 되었고 L50균주는 similarity가 96.2%로써 Sphinromonas sanguis의 근연종으로 동정되었다. 선발된 길항균주가 생산한 길항물질의 특성을 확인해본 결과, S. gallinarum을 저해하는 물질이 고분자성 물질이고 내열성임을 추정 할 수가 있었다. S. sanguis Ll9의 경우 배양 20시간 이후부터 길항물질이 생산되었으며 탄소원, 질소원을 각각 maltose, $(NH_4)_2SO_4$를 첨가하였을 때 가장 높은 길항력을 나타내었다. S. sanguis L33의 경우 배양 22시간 이후 부터 길항물질이 생산되었으며 탄소원, 질소원을 각각 galactose, urea를 첨가하였을 때 가장 높은 길항력을 나타내었다. S. sanguis L50은 배양 10시간 이후부터 길항물질을 생산하였으며 탄소원, 질소원을 각각 saccharose, $(NH_4)_2S_2O_8$음로 하였을 때 가장 높은 길항력을 나타내었다.