• 동아시아식생활학회지
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• 제23권3호
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• pp.311-319
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• 2013

The purpose of the present study is to investigate the effects of green tea catechin on microsomal phospholipase $A_2(PLA_2)$ activity and the arachidonic acid (AA) cascade in hearts of microwave exposed rats. Sprague-Dawley male rats weighing $100{\pm}10$ g were randomly assigned to one normal group and three microwave exposed groups. The microwave exposed groups were subdivided into three groups: catechin free diet (MW) group, 0.25% catechin (MW-0.25C group and 0.5% catechin (MW-0.5C) group according to the levels of dietary catechin supplementation. Rats were sacrificed $6^{th}$ day after microwave irradiations (2.45 GHz, 15 min). The heart microsome $PLA_2$ activity in the MW group was 130% greater than that of normal groups, whereas there was no significant difference between normal group and MW-0.25C, MW-0.5C group. The per- centage phosphatidyl ethanolamine (PE) hydrolyzed in the heart microsome in the MW was increased 54% by microwave irra- diation, whereas there was no significant difference between normal group and MW-0.5C group. The percentage phosphatidyl choline (PC) hydrolyzed in the heart microsome in the MW group was increased by 104% and by microwave irradiation, whereas there was no significant difference between normal group and MW-0.5C group. The formation of thromboxane $A_2(TXA_2)$ in the heart microsome was 70% greater in the MW group than in the normal group. However, the MW-0.25C and MW-0.5C group maintained the normal level. The formation of prostacyclin ($PGI_2$) in the heart microsome was 21% lower in the MW group than in the normal group, while that of MW-0.25C and MW-0.5C group were maintained in the normal group. The heart microsomal thiobarbituric acid reactive substances (TBARS) concentrations, as an index of lipid peroxide, were 71% greater in the MW group, as compared with normal group. However, the MW-0.25C and MW-0.5C group were 4.6% and 9.2% lower, respectively, than that of MW group. In conclusion, heart function appeared to be improved by green tea catechin supplementation due to its antithrombus action, which in return controls the AA cascade system.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.376.1-376.1
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• 2002

Phytochemical examination of Barks of Ulmus macrocarpa isolated two flavanone, three flavanonol, three flavan 3-ol and one procyanidin compounds. We also determinated the antioxidative activity of these compounds by measuring the radical scavenging effect on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Three flavan 3-ol (catechin, epicatechin and catechin-7-O-$\beta$-O-xylopyranoside) and procyanidin B1 showed significant antioxidative activity. (omitted)

• Journal of the Korean Wood Science and Technology
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• 제29권4호
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• pp.53-59
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• 2001

비자나무 잎을 아세톤-물의 혼합용액으로 추출하고 n-hexane, chloroform, ethylacetate 및 물 분획으로 분류하여 동결건조하고 분말상 화합물로 조제하였다. 그 중에서 ethylacetate 용성 추출물을 메탄올-물 및 에탄올-헥산(n-hexane)의 혼합용액을 사용하여 Sephadex LH-20 칼럼상에서 크로마토그래피를 수행하였다. 비자나무 잎의 추출성분은 대부분 (+)-catechin, (-)-epicatechin, (+)-gallocatechin 및 (-)-epigallocatechin과 같은 flavan 화합물과 3'-O-methyl-(+)-catechin 및 3'-O-methyl-(-)-epicatechin과 같은 flavan의 methyl ether 화합물로 구성되어 있었으며 그 이외에 benzoic acid계 화합물인 protocatechuic acid도 단리 되었다. 단리된 화합물은 $^1H$- 및 $^{13}C$-NMR, NOE와 CI-MS 분석에 의해 화학구조를 구명하였다.

• 한국식품영양과학회지
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• 제27권2호
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• pp.319-325
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• 1998

The purpose of this study was to investigate the effect of green tea catechin on microsomal mixed function oxidase(MFO) system of kidney and brain in streptozotocin(STZ) induced diabetic rats. Sprague-Dawley male rats weighing 140$\pm$10g were randomly assigned to one control and three STZ-diabetic groups. Diabetic groups wer classified to DM-0C(catechin 0%/kg diet), DM-0.5C (catechin 0.5%/kg diet), and DM-1.0C(catechin 1%/kg diet) according to the level of catechin supplementation. Diabetes were experimentally induced by intravenous administration of 55mg/kg body weight of STZ in citrate buffer(pH 4.3) after 4 weeks feeding of three experimental diets. Animals were sacrificed at the sixth day of diabetic state. The contents of cytochrome P450 in kidney were increased by 77, 42, 49% in DM-0C, DM-0.5C and DM-1.0C groups, respectively, than normal group. The contents of cytochrome P450 in brain were increased by 43% in DM-0C group than normal group, but those of DM-0.5C and DM-1.0C groups were similar to that of normal group. The contents of cytochrome b5 in kidney were increased by 78, 38, 49% in DM-0C, DM-0.5C and DM-1.0C groups, respectively, than normal group. Meanwhile, the contents of cytochrome b5 in brain were not significantly different among all groups. The activities of NADPH-cytochrome P450 reductase in kidney of DM-group were increased by 27% than normal group, but those of DM-0.5C and DM-1.0C groups were 13 and 15% lower than that of DM-0C group. The activities in brain were also increased by 31% in DM-0C group, but those of DM-0.5C and DM-1.0C groups were similar to than of normal group. Levels of TBARS (thiobarbituric acid reactive substance) in kidney were increased by 147, 60 and 59% in DM-0C, DM-0.5C, and DM-1.0C groups, respectively, compared with normal group, but those of DM-0.5C and DM-1.0C groups were 36, 35% lower than that of DM-0C group. Meanwhile, the levels of TBARS in brain were not significantly different among four groups. These results indicate that dietary catechins in green tea play a powerful antioxidant role in reducing the lipid peroxidation enhanced by activation of MFO system in STZ-induced diabetes.

• 생명과학회지
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• 제18권2호
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• pp.273-278
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• 2008

콜레스테롤 생합성 과정에 있어서 속도조절 단계 효소의 하나인 squalene synthase에 대한 저해물질의 탐색을 목적으로, 30종의 다양한 천연물을 대상으로 squalene synthase에 대해 저해효과를 검토한 결과 녹차추출물에서 비교적 저해활성이 높고 재현성이 있게 저해효과를 나타내는 것으로 확인되었다. 녹차에 함유되어 있는 squalene synaase에 대한 저해물질의 용매추출성을 검토한 결과 ethyl acetate와 n-butanol 층에 저해물질이 많이 함유되어 있는 것으로 확인되었으며 저해물질은 녹차의 polyphenol 화합물인 catechin에 의한 것으로 추정되었다. Catechin 표준용액의 각 농도에 따른 squalene synthase 저해작용을 살펴 본 결과, (-)-epigallocatechin gallate, (-)-epicatechin gallate, (-)-epigauocatechin, (-)-epicatechin, (+)-catechin의 순으로 저해활성이 강한 것으로 나타났으며 가장 강한 저해활성을 나타내는 (-)-epigallocatechin gallate의 $IC_{50}$값은 $90{\mu}M$이었다.

• 한국식품과학회지
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• 제37권4호
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• pp.513-518
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• 2005

포도종실추출물에 함유되어 강력한 항산화 작용을 나타내는 성분인 proanthocyanin의 구성 성분이면서 에피머인 (+)-catechin과 (-)-epicatechin을 CE법을 이용하여 분석하였다. CE법을 이용한 catechin류 분석의 최적 조건은 fused silica capillary$(20cm{\times}50{\mu}m)$, current $56{\mu}A$, voltage 10 kV, phosphate/borate buffer(pH 6.0), 온도 $20^{\circ}C$로서 (+)-catechin과 (-)-epicatechin을 6분 이내에 매트릭스의 방해없이 분석할 수 있었다. 비색법, HPLC법과 CE분석법의 특징을 비교해 보면 비색법은 (+)-catechin과 (-)-epicatechin합한 총 함량은 알 수 있으나 두성분의 분리는 할 수 없었다. 또한 HPLC방법은 표준품은 두 성분이 잘 분리되었으나 시료 분석 시 proanthocyanin을 가수분해하기 위해 첨가한 산으로 인해 시료가 강산성을 띠어 컬럼 손상되는 문제가 있어 직접 분석이 불가능하여 시료를 희석해야 했으며, 희석을 하여 분석할 경우에도 많은 잡 피크들로 정량적인 결과를 얻기에 용이하지 않았다. 한편 CE법의 경우 산 가수분해한 시료를 별다른 처리 없이도 다른 성분의 방해 없이 분석할 수 있었다. 분석소요시간의 경우 비색법은 실험단계가 복잡하여 많은 시간이 걸렸으며 HPLC는 15분 그리고 CE는 6분 이내에 분석이 가능하였다. 재현성과 직선성을 보면 HPLC와 CE의 방법이 모두 양호하였고 검출한계에 있어서는 CE법이 0.035mg/L로서 검출감도가 매우 우수하였다. 이와 같이 CE법은 포도종실에 존재하는 (+)-catechin과 (-)-epicatechln을 분석하는데 방법의 용이성, 분석결과의 정확성에 있어서 기존 방법인 비색법과 HPLC 방법보다 우수한 결과를 나타내었다.

• Journal of the Korean Wood Science and Technology
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• 제31권2호
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• pp.45-51
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• 2003

큰잎자작 변재의 메탄올(methanol, MeOH) 조추출물로부터 silica gel column, CPC 등의 크로마토그라피를 이용하여 4종의 화합물을 단리하였으며, 단리물질에 대한 NMR 등의 기기분석 결과, flavonoid 및 lignan 배당체인 catechin 7-O-𝛽-D-xylopyranoside, lyoniresinol 9'-O-𝛽-D-glucopyranoside, 그리고 diarylheptanoid인 11-oxo-3, 8, 12, 17-tetrahydroxy-9-ene [7, 0]-metacyclophane 및 11-oxo-3, 8, 9, 10, 12, 17-hexahydroxy [7, 0]-metacyclophane으로 각각 동정하였다.

• 한국수산과학회지
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• 제27권2호
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• pp.166-172
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• 1994

To evalulate the antioxidant effect of flavonoid(+)-catechin on n-3 polyunsaturated fatty acids in vivo, rats were fed with diets containing $5\%$ corn oil(CO), $5\%$ corn oil and $15\%$ purified fresh fish oil(FO) or peroxidized fish oil(PFO) for 10 days. To accerelate lipid peroxidation, all of them were injected with 60mg phenobarbital(a day per kg body weight), and treated with phorone(diisopropylidene acetone) before the rats were killed. Contents of triglyceride, phospholipid, cholesterol and lipid peroxide and the activities of GOT, GPT in serum and total lipid and cholesterol content in liver of PFO group rats were significantly higher than those of the FO one. Contrary to our expectations, the activities of superoxide dismutase (SOD), catalase and glutathione peroxidase(GSH-Px) in liver of the FO group were ]ewer than those of the PFO group. These results might be explained as the results of homeostasis. Even though the hepatic glutathione were depleted, catechin and a-tocopherol inhibited production of lipid peroxide effectively. These results suggested that catechin be considered an antioxidative and hepatoprotective agent.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1984년도 학술대회지
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• pp.257-275
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• 1984

Enzymatic browning is considered desirable in tea and tobacco processing but undesirable in many fruits processing at the present time. It is necessary to understand the nature of the enzyme, phenoloxidase, in order to control browning reactions, and extend its effects to formation of browning products as antioxidants in ginseng. Ginseng exhibits antioxidant activity when incorporated with turkey dark meat patties. The activity in red ginseng showed about two times stronger than white ginseng. One of the phenolic antioxidants from fresh, white and reprocessed white ginseng was identified as phenol 2.6 Bis(1.1 dimethyl ethyl) 4-methyl among several unknown compounds by GC/mass spectrometer. In red ginseng, no phenol 2.6 Bis (1.1 dimethyl ethyl) 4-methyl was detected, the compound may be polymerized by phenoloxidase and form some higher molecular compounds which may possess high antioxidant activity. Phenoloxidase isozymes in fresh Korean ginseng (panax ginseng C.A. Meyer) were extracted with phosphate buffer at pH 7.3. The isozymes were purified through ammonium sulfate fractionation, dialysis and chromatography on a DEAE-cellulose column. Two groups of phenoloxidase were shown to be present, one in the floating agglomerated group and the other in the precipitate. group from the 0.85 saturation ammonium sulfate. The DEAE-cellulose column chromatography, the phenoloxidase isozyme present in the precipitate appears as the first peak (I), and that in the agglomerate in the second peak (II). Isozyme I showed higher activity with catechin and catechal, and isozyme II showed higher activity with p-cresol. The isozyme showed two optimum pH activity one at pH 4.5 and the other at 8.5 with catechin as substrate. Korean ginseng phenoloxidase has high heat stability. When heated at $75^{\circ}C$ for 2 hours, its activity remained $90\%\;and\;80\%$ on phenoloxidase I and II respectively. Phenoloxidase I was most active on (+) catechin followed by p-cresal, catechol and epicatechin. Phenoloxidase II was most active on p-cresal followed by (+) catechin, catechol, p-coumanic acid and epicatechin. Sodium bisulfite, sodium cyanide, ascorbic acid glutachion in the oxidized form, sodium diethyl dithiocarbomate and ethylendiamine tetra acetate (EDTA) acted as inhibitors. Red ginseng color development was initiated by phenoloxidase and finished by a followed sun drying process. The antiaging activity of ginseng may be initiated by the antioxidant in the ginseng.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권1호
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• pp.1-10
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• 2008

Oral squamous cell carcinoma (OSCC) is the most frequent form of oral cancer and holds the eighth position in the cancer incidence ranking. OSCC patients are treated by classical therapeutic modalities consisting of surgery, radiotherapy, and/or chemotherapy. But OSCC still shows significant mortality rates. Thus, new therapeutic approaches have been investigated and the most promising one is naturally acquired agents with known anti-cancer effects. Genistein is a compound extracted from soy bean. Its anti-cancer effect on breast cancer is well established now and it is investigated whether it has similar effect on OSCC. It inhibited the growth and invasive-ness of OSCC cells in vitro, but these effects did not work in living animals in vivo. Catechin is a compound from green tea and its anti-cancer effect on OSCC is known better than other agents. Catechin showed its anti-cancer effect in vitro via induction of apoptosis, cell cycle arrest, inhibition of growth, and down-regulation of invasion/metastasis. These effects were confirmed in vivo with mouse model. Cordycepin is one of major pharmacologically important components in Cordyceps Militaris and may exert its anti-cancer effect as an adenosine receptor agonist. In recent study, it inhibited the proliferation of OSCC cells via A3 adenosine receptor. But because there is very scarce evidence on this effect, more researches are needed on this theme.