• Title/Summary/Keyword: bromobenzene

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Substituent Effects on the Leaving Groups in Benzyl Arenesulfonates (Benzyl Arenesulfonate의 離脫基의 置換基效果에 關한 硏究 (第 1 報))

  • Yoh Soo Dong
    • Journal of the Korean Chemical Society
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    • v.19 no.2
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    • pp.116-122
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    • 1975
  • Determination has been made of the kinetics of the reaction of benzyl arenesulfonates with pyridine in acetone. The substituent effects of the leaving groups in benzyl arenesulfonates are correlated by Hammett equations, with the exception of p-MeO and $p-NO_2$ groups, where the electron attracting substituents in the benzyl arenesulfonate increase the rate. The substituent effects of the leaving groups are as expected due to the nucleophilic attack of amine on the benzyl carbon atom. This can be understood in terms of changes in bond formation (C-N) and bond breaking (C-O) in the transition state with charges in electron-attracting ability of the substituents. The predicted substituent effects may indicate a small increase in bond formation and thus a tighter transition state, in benzyl p-bromobenzene sulfonate than in benzyl p-nitrobenzenesulfonate. Predicting made by Thornton concerning the substituent effects on $S_N2$ transition state structures agrees with the changes in bond formation and bond breaking.

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The Acute Toxicity of 1,2,4-Trichlorobenzene in Sprague-Dawley Rats Depleted of Glutathione by Treatment with Buthionine Sulfoximine (BSO 유도 글루타치온 저감 흰쥐에서 1,2,4-trichlorobenzene의 급성독성)

  • 안영수
    • Toxicological Research
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    • v.12 no.1
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    • pp.29-34
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    • 1996
  • 1,2,4-trichlorobenzene (1,2,4-TCB) is used as a dye carrier, an intermediate in the syn[hesis of herbicides, aflame retardant, and for other purpose. After a single oral administration of 1,2,4-TCB (200 mg/kg, 400 mg/kg) in rats, toxic effects were studied by means of serum biochemical and hematological analysis, and liver calcium concentration. Administration of 1,2,4-TCB resulted in dose-dependent manner liver and kidney damage being suggested by increased serum alanine aminbtransferase (ALT) activities, liver calcium concentration and blood urea nitrogen (BUN). Pretreatment with DL-buthionine sulfoximine (BSO, 2 mmol/kg, i.p.) considerably decreased liver glatathione concentration, which was accompanied by markedly elevated serum ALT activites. It is well-known that toxicity of halogenated benzene such as bromobenzene, 1,4-dichlorobenzene is increased by pretreatment of phenobarbital, and protected by pretreatment of cytochrorn P450 inhibitor including metyrapone. However, there were no obvious alterations in toxicity of 1,2,4-TCB by pretreatment of phenobarbital or metyrapone. In comparison with control group, treatment groups exhibited significant changes in some parameters of hematological analysis but all hematological values remained within normal ranges.

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Composition of the Essential Oil of Chrysanthemum sibiricum, and Cytotoxic Properties

  • Lee, Kyung-Tae;Choi, Jong-Won;Park, Jong-Hee;Jung, Won-Tae;Jung, Hyun-Ju;Park, Hee-Juhn
    • Natural Product Sciences
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    • v.8 no.4
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    • pp.133-136
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    • 2002
  • GC-MS data on the volatile oil (CS-oil) of Chrysanthemum sibiricum herbs led to the identification of 2-methoxythioanisol, (+)-camphor, geraniol, citral, thymol, eugenol, ${\beta}-caryophyllene$ oxide, ${\beta}-caryophyllene$, ${\beta}-eudesmol$, juniper camphor together with an unknown substance using the mass spectral library and literature data. CS-oil exhibited significant cytotoxicities on HL-60 $(IC_{50}\;12.5\;{\mu}g/ml)$ cell and mild on HepG-2 cell $(IC_{50}\;102.4\;{\mu}g/ml)$, though the antioxidant ability was found not to be potent $(IC_{50}\;97.2\;{\mu}g/ml)$. However, the component eugenol showed potent antioxidant ability but mild cytotoxicity. Methyleugenol with no phenolic OH showed less potent cytotoxic and antioxidative properties than eugenol suggesting that phenolic OH plays an important role for the cytotoxic and antioxidant abilities. The oil-pretreatment prevented lipid peroxidation induced by bromobenzene in the rat. Therefore, it was demonstrated that CS-oil could be a cytotoxic agent with antioxidant properties.

Anti-lipid Peroxidative Principles from the Stem Bark of Kalopanax pictus Nakai

  • Choi, Jong-won;Han, Youn-Nam;Lee, Kyung-Tae;Park, Kun-Yong;Kwak, Tae-Soon;Kwon, Sang-Hyuk;Park, Hee-Juhn
    • Archives of Pharmacal Research
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    • v.24 no.6
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    • pp.536-540
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    • 2001
  • Hepatic lipid peroxide contents were examined in bromobenzene-treated rats firstly after the oral administration of MeOH extract of Kalopanax pictus stem bark its n-BuOH fraction, EtOAc fraction and an alkaline hydrolysate of the n-BuOH fraction, and secondly after the intraperitoneal administration of hederagenin monodesmosides and bisdesmosides. Two hederagenin monodesmosides, kalopanaxsaponin A (KPS-A) and sapindoside C, exhibited significant anti-lipid peroxidation effects after intraperitoneal administration at doses of $10-30{\;}{\mu}mole/kg$, whereas their bisdesmosides did not exhibit any significant activity. These results suggest that it is the hederagenin monodesmosides that are responsible for anti-lipid peroxidation in vivo. The activity of KPS-A was established by the observation of decreased aminopyrine N-demethylase activity and increased epoxide hydrolase activity.

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Hepatic Detoxification and Antioxidant Activity in Sea-urchin Roe and Ethanol Extract of Roe (성게 부위별 및 그 추출물의 간 해독과 항산화 활성 효과)

  • Lee, Seung-Joo;Ha, Wang-Hyun;Choi, Hye-Jin;Cho, Soon-Yeong;Choi, Jong-Won
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.43 no.5
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    • pp.428-436
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    • 2010
  • Sea-urchins (Anthocidaris crassispina) are widely distributed in the East Sea of Korea. The aim of this study was to evaluate the hepatoprotective effects of sea-urchin roe on bromobenzene (BB)-induced liver damage in rats. The antioxidative and detoxifying properties of sea-urchin roe in BB-poisoned rat liver was examined by chemical analysis of serum aminotransferase (AST, ALT), glutathione S-transferase (GST), $\gamma$-glutamylcystein synthetase, glutathione reductase, epoxide hydrolase, amino-N-demethylase (AD), aniline hydrolase (AH) enzyme activity, as well as lipid peroxide and glutathione contents. Sea-urchin roe inhibited the increase of serum AST, ALT enzyme activity. Increasing lipid peroxide contents and AD and AH activities were significantly decreased in ethanol extract of sea-urchin roe. GST, $\gamma$-glutamylcystein synthetase, glutathione reductase and epoxide hydrolase enzyme activities increased in sea-urchin roe-fed group, compared with the BB-treated group. These results suggest that sea-urchin roe facilitates recovery from liver damage by enhancing antioxidative defense mechanisms and hepatic detoxication metabolism.

In vivo and In vitro Anti-lipid Peroxidative Effect of the Extract Complex of Korean Anti-thirst Drugs (한방 소갈약 추출물 및 복합물에 의한 In vivo 및 In vitro 지질과산화 저해효과)

  • 이경태;박동영;박희준;정현주;박건영;최종원
    • YAKHAK HOEJI
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    • v.46 no.5
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    • pp.358-363
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    • 2002
  • In Oriental medicine, the prescriptions composed of several herb medicines have been used. It is still unclear how the sum of several extracts of anti-thirst drugs represents the anti-lipid peroxidative action. Three anti-thirst herb medicines, Kalopanax pictus (K), Pueraria thunbergiana (P) and Rhus verniciflua (R), were extracted with MeOH and $H_2O$, respectively, and the former one was fractionated into the resultant EtOAc extract. Each extract was reconstituted to give KPR311, KPR131 and KPR113 where, for example, KPR311 represents the complex of K-P-R {3:1:1 (w/w/w)} of the three extracts. The order of the inhibitory effect in bromobenzene-induced lipid peroxidation in rats was as follows: EtOAc extract>$H_2O$ extract>MeOH extract. Extract complexes were found to be more potent than the extracts of individual crude drugs. The KPR131 of EtOAc extract was found to be the most potent among the tested samples. These anti-lipid peroxidative effects were also supported by the decrease of aniline hydroxylase activity and aminopyrine N-demethylase activity, on the other hand by the increase of epoxide hydrolase activity. All the tested samples were assayed in vitro antioxidative effects such as DPPH assay, ADP/NADPH/Fe$^{3+}$ assay and ascorbic acid/Fe$^{2+}$ assay. The EtOAc extracts also showed the most significant antioxidative effects. These results suggest that the sum of anti-thirst drugs could reflect the effects of respective crude drugs.s.s.

Motorsports and Engineering Aspects (모터스포츠의 공학적 접근)

  • 장성국
    • Journal of the korean Society of Automotive Engineers
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    • v.24 no.5
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    • pp.98-103
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    • 2002
  • 이제 카트 정렬과 휠 셋업에 필요한 최적의 변수들을 알아보았다. 실제 세팅은 위에서 언급한 내용 이외에도 많은 것들을 고려하여야 한다. 타이어 접지력의 세팅은 경기장, 날씨, 제품의 불 균일성 등을 고려하여 야 한다. 즉, 어떤 경기장은 코너의 반경이 다른 경기 장 보다 크며 어떤 경기장은 코너가 매우 많기도 하여 세팅을 상황에 맞게 하여야 하는 것이다. 각각의 변수를 세팅할 경우는 중간 값을 취하는 것이 바람직하여 이 중간 값을 취하는 것이 바람직하며 이 중간 값을 각각의 경기장의 특성에 맞추어 변화시키면 되는 것이다. 예를 들면, 접지력이 작게 발생되는 경기장(혹은 매우 추운날씨) 에서는 캐스터를 코기 하여 초기 회전 발생이 용이하게 할 수도 있다. 또한 토우인 값을 크게 하여 타이어가 마찰을 더욱 많이 발생하여 타이어의 온도가 급격히 상승하여 원하는 접지력의 수준에 용이하게 도달할 수 있게 하는 것이다. 그러나 이러한 세팅은 다른 핸들링 문제를 야기할 수 있다는 것을 이해하여야 하며 이러한 문제를 해결하는 또 다른 노력이 필요하게 되는 것이다. 가장 중요한 것은 후륜 내측으로부터는 조종 성능을 향상시키는데 필요한 접지력을 거의 기대하지 못한다는 것이며 마찰이 적게 발생하여 손쉽게 동력 손실을 초래하고 있다는 것이다. 그러므로 회전을 할 경우에도 속도를 낮추어서는 안되며 이렇게 하이야 핸들링이 매우 용이하게 되는 것이다. 그러나 위의 설명에서도 보았듯이 일부 세팅을 변경하면 여러 곳이 그 효과가 나타난다. 예를 들어 후륜의 간격을 변화시키면 카트에서 무게이동 뿐만 아니라 회전 시에 가속이나 감속에 의한 회전 토크의 효과도 달라지게 된다. 특정한 세팅의 변화가 어떻게 작용할 것이라는 확신을 가지고 있다고 할지라도 세팅에서 가장 중요한 것은 주행 기록이다. 여기서 설명되어진 많은 내용이 주행 기록을 향상시키기를 바라는 바이다.간이 육색과 총육색소 함량에는 영향을 미치지 않는 것으로 나타났다. 관능적 특성평가 중 육색과 육즙참출은 대조구와 비교하여 CLA급여 처리구가 유의적인 차이가 없었으나, 근내지방 축적 정도와 전체적인 기호성은 대조구에 비하여 CLA 급여 처리구가 유의적으로 높은 평가를 받았다(p<0.05). 간격은 술 후 1년 후까지도 지속적으로 감소하는 경향을 보였다. 따라서 이 기간동안에는 추적관찰이 필요한 것으로 생각된다.경미하게 나타났으며, 이는 2% 흥국 첨가식이의 섭취로 인한 bromobenzene 대사 및 유해산소 해독의 촉진에 기인되기 때문일 것으로 생각된다.다.과 및 지질과산화억제효과의 순과 일치하였다. 총 flavonoid 함량은 DPPH 라디칼 제거효과에 대한 $IC_{50}$/ 값과 높은 상관관계(r=-0.9924, p<0.01)를 나타내었다.이 우수한 심근보호 효과를 나타내나, 허혈시간이 2시간을 초과하면 심근의 혈역학적 기능과 미세구조의 변화는 중등도의 저온(22∼24$^{\circ}C$)에서 유의하게 악화되었다. 이 같은 결과로 볼 때 심근 허혈시간이 2시간을 초과한다면 심근 온도를 낮추어야 할 것으로 판단된다. 7.2, with 64.0% of office workers having an average level between 6- and 9. The degree of stress was higher for females than males, for unmarried salaried and hot-tempered persons. Those not doing exercise were subject to the highest levels of stress, and those a having sufficient sleep were found to be subject to less stress.

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Quality Properties of Capsule Type Meju Prepared with Aspergillus oryzae (Aspergillus oryzae를 이용한 캡슐형 메주의 품질특성)

  • 최재훈;권선화;이상원;남상해;최상도;박석규
    • Food Science and Preservation
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    • v.10 no.3
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    • pp.339-346
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    • 2003
  • In order to improve some problems such as contamination of undesirable mold, mycotoxin production and excessive drying on the surface of traditional meju, we developed a capsule type-meju(CM) coated with steamed black bean and Aspergillus oryzae - rice koji(0.3%, w/w) mixture to surface of traditional meju and fermented at 25$^{\circ}C$ for 14 days under 80% relative humidity. Contamination of undesirable mold on the surface of CM was not detected within 2 weeks and some genus Penicillium molds on control meju without koji were found naturally after 12 days of fermentation. The moisture content of meju was showed to be in the range of 34.7 - 29.4% being 32.7%(w/w) of mean value. Titratable acidities in CMs prepared with black bean(BCM) and soybean(SCM) were much higher than that in control meju, and BCM was similar to SCM. Free sugar content in BCM(123.98 mg%) was 10 times and 2.1 times higher than that in control meju(15.02 mg%) and SCM(59.85 mg%), respectively. Amino type nitrogen content in control meju was 147.00 mg% and its content in BCM(255.50 mg%) was 1.37 times higher than that in SCM(187.25 mg%). Total organic acid content in BCM(95.98 mg%) and SCM(1l9.98 mg%) were much higher than that in control meju(26.44 mg%), and then lactic and malic acid contents were markedly changed according to capsulation of meju. Lightness value(L) of Hunter color index was much higher in BCM than in SCM. Fatty acid composition of CM was not different as compared to control meju. Total free amino acid content in BCM(1039.70 mg%) was 4.4 times and 2.4 times higher than that in control meju(236.45 mg%) and SCM(556.07 mg%), respectively.