• Applied Biological Chemistry
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• 제40권4호
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• pp.277-282
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• 1997

아라비돕시스 탈리아나의 아세토락테이트 합성 효소 (ALS)를 그 유전자를 포함하고 있는 대장균 MF 2000/pTATX로부터 부분 정제하였다. 부분 정제된 이 효소를 가지고 여러 가지 변형 화학물질들 즉, 요오드아세트산, 요오드아세타마이드, N-에틸말레이미드 (NEM), 5,5'-디티오비스(2-니트로벤조산) (DTNB), 파라염화수은벤조산 (PCMB), 그리고 페닐글리옥살 등에 대한 민감성을 조사하였다. PCMB가 가장 민감하게 저해를 했으며, DTNB와 NEM이 그 뒤를 따랐다. 이 효소의 기질인 피루브산이 요오드아세트산에 의한 활성 저해를 보호하지 못하였으므로 기질의 결합에 시스테인의 관련이 없는 것 같이 보인다. 한편, 기질이 페닐글리옥살에 의한 효소의 활성 저해를 부분적으로 보호하는 것으로 보아 기질이 아르기닌기와 상호 작용함을 암시하고 있다. 부분 정제된 효소는 발린과 이소루신에 민감하게 방해를 받았으나 루신은 그렇지 않았다. 그러나, PCMB로 변형시킨 효소는 되먹임 방해를 더 강하게 받았다. 그 외 ALS에 대한 새로운 제초제 후보인 피리미디설퍼 벤조산 유도체의 저해 효과를 검토하였다.

• 생약학회지
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• 제25권2호
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• pp.121-131
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• 1994

Two kinds of new lectins, CATL-I and CATL-II, were partially purified from the intestine of Chlorostoma argyrostoma turbunatum by physical saline extraction, salt fractionation, ion exchange chromatography and gel filtration. CATL-I and CATL-II were purified 39.4 and 15.8 fold with a yield of 8.8 and 7.4%, respectively. On polyacrylamide gel electrophoresis, CATL-I demonstrated one major and one minor bands. This lectin agglutinated human and other animal erythrocytes nonspecifically and also agglutinated murine splenic lymphocytes. Carbohydrate specificity of the lectins was determined by inhibition of the agglutinability by methyl-${\alpha}-_D$-galactopyranoside and $_L-rhamnose$ at a final concentration of 6 mM. The lectins contained relatively high amounts of acidic amino acids, but the contents of sulfur containing amino acids were very low or was not estimated. Immunochemical studies were carried out to identify some properties of marine animal lectins.

• Bulletin of the Korean Chemical Society
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• 제23권7호
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• pp.990-994
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• 2002

Hydroxybenzothiophenes, dihydroxy-benzothiophenes, and benzothiophenedione were identified as inter-mediates of benzothiophene (BT) exposed to ultrasonic irradiation. It is proposed that benzothiophene is oxidized by OH radical to sequentially for m hydroxybenzothiophenes, dihydroxybenzothiophenes, and benzothiophenedione. Benzothiophene is decomposed rapidly following pseudo-first-order kinetics in a first-order manner by ultrasonic irradiation in aqueous solution. The toxicity of sonochemically treated solutions was checked by E. coli and a less inhibition in bacterial respiration was observed from the 120-min treated benzothiophene sample than from the untreated benzothiophene sample. Also evolution of carbon dioxide and sulfite was observed during ultrasonic reaction. A pathway for ultrasonic decomposition of benzothiophene in aqueous solution is proposed.

• Bulletin of the Korean Chemical Society
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• 제12권1호
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• pp.93-97
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• 1991

Rate constants have been measured spectrophotometrically for the reactions of alkali metal ethoxides with 4-nitrophenyl benzoate, S-4-nitrophenyl thiobenzoate and 4-nitrophenyl thionbenzoate in ethanol at 25$^{\circ}$C. Substitution of S for O in the leaving group has not affected reactivity significantly, while the effect of the similar replacement in the acyl group has led to rate decrease by a factor of 10, although pronounced rate enhancements have been expected for both systems. The replacement of O by a polarizable S has also influenced the reactivity of the esters toward alkali metal ethoxides, i.e. the reactivity decreases as the size of the metal ion decreases. The alkali metal ions have showed inhibition effect instead of catalytic effect which would have been expected for the present system. The effect of replaced sulfur atom on the reactivity for the present system is attributed to the nature of hard and soft acids and bases.

• Toxicological Research
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• 제17권
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• pp.251-256
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• 2001

The expression of phase II detoxifying enzymes is affected by a variety of compounds and the induction of the enzymes plays an essential role in chemoprevention. A variety of phytochemicals such as sulfur-containing chemoprotective agents (SCC) may trigger cellular signals and activate phase II gene expression through ARE activation. see induces glutathione S-transferases. Studies were conducted to investigate the role of mitogen-activated protein (MAP) kinase and phosphatidylinositol 3-kinase (PI3-kinase) in the induction of GST (e.g. rGSTA2) by sec. We also studied the MAP kinase pathway responsible for the GST expression by see and compared that with the pathway activated by oxidative stress as a result of sulfur amino acids deprivation (SAAD). see inhibited phosphorylation of ERK1/2 although the effect of see on JNK and p38 MAP kinase was minimal. Wortmannin and LY294002. PI3-kinase inhibitors. abolished the increases in rGSTA2 mRNA and protein levels by SCC. Deprivation of cystine and methionine caused oxidative stress in H4IIE cells. as evidenced by a decrease in the reduced glutathione and an increase in prooxidant production. Electrophoretic mobility shift assay revealed that the ARE complex consisting of Nrf-1/2 and Maf proteins was activated 12~48 h. The rGSTA2 mRNA and protein levels were increased by SAAD. Activation of ARE and induction of rGSTA2 were both completely inhibited by PI3-kinase inhibitors. Inhibition of p38 MAP kinase by SB203580 prevented the ARE-mediated rGSTA2 induction. The results of this study showed that PI3-kinase might play an essential role in the ARE-mediated rGSTA2 induction by see or SAAD and that the dual MAP kinase pathways were responsible for the enzyme induction.

• 한국세라믹학회지
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• 제51권6호
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• pp.584-590
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• 2014

Air-cooled slag showed grindability approximately twice as good as that of water-cooled slag. While the studied water-cooled slag was composed of glass as constituent mineral, the air-cooled slag was mainly composed of melilite. It is assumed that the sulfur in air-cooled slag is mainly in the form of CaS, which is oxidized into $CaS_2O_3$ when in contact with air. $CaS_2O_3$, then, is released mainly as $S_2O{_3}^{2-}$ion when in contact with water. However, the sulfur in water-cooled slag functioned as a constituent of the glass structure, so the$S_2O{_3}^{2-}$ ion was not released even when in contact with water. When no chemical admixture was added, the blended cement of air-cooled slag showed higher fluidity and retention effect than those of the blended cement of the water-cooled slag. It seems that these discrepancies are caused by the initial hydration inhibition effect of cement by the $S_2O{_3}^{2-}$ ion of air-cooled slag. When a superplasticizer is added, the air-cooled slag used more superplasticizer than did the blast furnace slag for the same flow because the air-cooled slag had higher specific surface area due to the presence of micro-pores. Meanwhile, the blended cement of the air-cooled slag showed a greater fluidity retention effect than that of the blended cement of the water-cooled slag. This may be a combined effect of the increased use of superplasticizer and the presence of released $S_2O{_3}^{2-}$ ion; however, further, more detailed studies will need to be conducted.

• 원예과학기술지
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• 제31권5호
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• pp.633-639
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• 2013

딸기의 잿빛곰팡이병과 흰가루병을 방제하기 위해 개화기에 살균제 처리가 요구된다. 최근에 딸기에 등록된 살균제들이 딸기 화분 발아에 미치는 영향은 거의 알려지지 않았다. 따라서 본 연구에서는 in vitro 상에서 딸기 3품종의 화분에 대한 24종의 살균제와 6종의 친환경자재에 대해 발아에 미치는 영향을 조사하였다. 딸기의 화분은 18% sucrose agar 배지에서 $25^{\circ}C$로 처리되었을 때 쉽게 발아되었으며, '설향', '매향', '금향'의 평균 화분 발아율은 각각 15.3, 18.4, 30.7%을 보였다. Pyraclostrobin, azoxystrobin, kresoxim-methyl, dichlofluanid, iminoctadine tris, sulfur는 무처리구 대비 93.8% 이상의 화분 발아 억제가를 나타내었다. 반면, simeconazole과 procymidone 살균제의 화분 발아율은 영향이 가장 적었다. 이 in vitro 검정 결과는 딸기 재배농가의 개화기 살균제 선정에 대한 정보를 제공할 수 있을 것이다.

• 대한수의학회지
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• 제31권3호
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• pp.241-251
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• 1991

In order to investigate the effect of Panax ginseng extract and it's degree in mucociliary change of mice nasal septum epithelia exposured to sulfur dioxide, 96 ICR male mice were used. They were at first divided the 4th week, the 8th week or the 16th week groups according to the age after birth and 6 hour or 12 hour groups according to the $SO_2$ gas exposured hour in a day, and at control, 50mg, 100mg and 200mg injection groups according to the dosage of the freeze-drying powder of the ginseng extract which was injected into the mouse peritoneal cavities in the condition of the solution solved with physiological saline solution. Each subgroups which were divided finaly included 4 male mice. The histological tissue sections for observation were made from nasal septum, posterior nasal orfice and trachea. The results obtained by experiments were summarized as followings. 1. The loss of the nasal mucosa epithelial cilia of the mouse exponsure to the $SO_2$ gas after ginseng extract injection was apparently diminish eompare to those exposured only $SO_2$ gas without pretreatment of ginseng extract (p<0.01). 2. The inhibition effect for the loss of nasal mucocilia according to the ginseng extract dosages not found in this research (p>0.05). 3. There were differences in the loss of nasal mucosa cilia according to the $SO_2$ gas exposure time between the control group and ginseng extract pretreatment group (p<0.01). 4. According to the increase of the postnatal time, there were remarkable differences between the control group and the ginseng extract pretreatment groups in the loss of nasal mucosa cilia (p<0.01). 5. Ciliary changes of the posterior nasal orifice and trachea according to the $SO_2$ gas exposure time, mice age and ginseng dosages, were not dearly observed in this light microscopical observation.

• 한국식품영양학회지
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• 제36권6호
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• pp.572-580
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• 2023

Hypertension is characterized by excessive renin-angiotensin system activity, leading to blood vessel constriction. Several synthetic compounds have been developed to inhibit renin and angiotensin-converting enzyme (ACE). These drugs often have adverse side effects, driving the exploration of plant protein-derived peptides as alternative or supplementary treatments. This study assessed the phenolic compound and amino acid content and the antioxidant and antihypertensive activity of 5 South Korean staple crops. Sorghum had the highest phenolic compound content and exhibited the highest antioxidant activity. Millet grains, particularly finger millet (38.86%), showed higher antihypertensive activity than red beans (14.42%) and sorghum (17.16%). Finger millet was found to contain a large proportion of branched-chain, aromatic, and sulfur-containing amino acids, which are associated with ACE inhibition. In particular, cysteine content was positively correlated with ACE inhibition in the crops tested (r=0.696, p<0.01). This study confirmed that the amino acid composition was more correlated with the antihypertensive activity of grains than the phenolic compound content. Finger millet mainly contained amino acids, which have higher ACE inhibitory activity, resulting in the strongest antihypertensive activity. These findings underscore the antihypertensive potential of select crops as plant-based food ingredients, offering insight into their biological functions.

• 한국응용곤충학회지
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• 제11권1호
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• pp.19-23
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• 1972

1. 사과나무 부란성병해를 일으키는 병원균을 사과 주산지인 충남북, 경북등 3개도에서 조사하였으며 살균제의 효과를 실내에서 검정하였다. 2. 병윈균은 Valsa mali (부란병) 및 Botryosphaeria ribis(동부병)은 경북, 충남. 충북 등 3개도 모두 분포하며 Phomopsis truncicola (동고병)만은 충북에서는 없었다. Valsa mali는 어느 지역에서나 가장 많이 발견되었으나 천원지방에서는 Botryosphaeria ribis가 더 많앗다. 3. 저지대에 의한 Valsa mali의 산균효과나 병원균을 접종한 수피의 침투효과에서 수은제 , 석회유황합제의 효과가 좋았고 다음으로 황산옥시키노린제, 유황제가 좋았고 알콩등의 효과는 인정되지 않았다.