• 한국미생물·생명공학회지
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• 제25권2호
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• pp.144-150
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• 1997

After DNA damage, umuDC is the only SOS operon that must be induced to promote SOS mutagenesis in Escherichia coli. The recombinant plasmid pBC401 and pBC402 were constructed to fuse the lac structural genes with promoter region of umuDC operon to induce the expression of lacZ gene by DNA damage. We transformed the plasmid pBC401 and pBC402 into E. coli MC1061, lacZ deleted strain and determined the activity of $\beta$-galactosidase for various mutagen; UV, mitomycin C (MMC), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), 4-nitroqunoline-1-oxide (NQO), ethyl methanesulfonate (EMS). The $\beta$-galactosidase activities of PBC401 and pBC402 for UV, MMC, and NQO were increased in proportion to expression time until 3 hours thereafter, the activities were constant or slightly decreased. The activities for MNNG and EMS were not so high as for UV, MMC, and NQO. When MNNG and EMS were treated, $\beta$-galactosidase activity of pBC402 was slightly lower than pBC401 but when UV, MMC, and NQO were treated in pBC402, $\beta$-galactosidase activity was slightly higher than in pBC401. Therefore, the pBC402 was better than the pBC401 in terms of sensitivity for frameshift mutagen. We suggest that the plasmid pBC401 and pBC402 are easy to detect mutagens which cause frameshift mutation rather than point mutation.

• Preventive Nutrition and Food Science
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• 제4권1호
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• pp.38-42
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• 1999

Antimutagenic effects of 5 kinds of kochujang(Korean red pepper soybean paste) samples compared with doenjang(Korean soy paste) were studied using the Ames test with Salmonella typhimurium TA100 and the SOS chromotest, with E. Coli PQ37. Th eantimutatenic effects of methanol extracts from red pepper powder and meju(fermented soybean) powder, the major ingredients of the kochujang,were also evaluated for the mutagenicity of aflatoxin B1 (AFB1) in the Ames assay. The methanol extracts from the kochujang samples showed lower antimutagenicities than those of doenjang against AFB1 and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in the Ames assay. Traditional kochujang I and II exhibited strong antimutagenic activity against AFB1 and MNNG. The traditional kochujang samples against MNNG were aslo observed in the SOS chromotest system with the same fashions as shown in the Ames mutagenicity test. The methanol extracts from meju powder had the strongest inhibitory effects on mutabenicity induced by AFB1, however, those form red pepper powder showed lower inhibition rate than kochujang. These results suggest that traditional kochujang exhibit higher antimutagenic acitivity than the commercial variety, and that meju powder seems to be one of the major antimutagenic components in kochujang.

• Asian Pacific Journal of Cancer Prevention
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• 제15권15호
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• pp.6363-6367
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• 2014

Purpose: This study was conducted to assess the preventive effect of Actinidia valvata Dunn (AVD) extract on an animal model of gastrointestinal carcinogenesis on the basis of changes in tumor incidence, cell proliferation, and apoptosis. Materials and Methods: Seventy-five male Wistar rats were divided into five different treatment groups with 15 rats in each group. Group I was given normal feed, whereas Groups II to IV were treated with 10% sodium chloride in the first six weeks and 100ug/mL of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in drinking water for 24 weeks. Group II was then given normal feed, whereas Group III was given AVD extract (0.24g/kg/day) for 12 weeks. Group IV was given AVD extract from the first week to the 36th week, whereas Group V was treated with AVD extract alone for 36 weeks. All rats were sacrificed at the end of the 36-week experiment and assessed for the presence of gastrointestinal tumors. The occurrence of cancer was evaluated by histology. Bax, Bcl-2, Caspase-3, and cyclinD1 were determined by immunohistochemical staining and Western blotting. Results: The incidences of gastric cancer were 0% in Group I, 73.3% in Group II, 33.3% in Group III, 26.7% in Group IV, and 0% in Group V. Bcl-2 and cyclinD1 expression was decreased in AVD extract treated groups, whereas Bax and Caspase-3 expression was increased. Comparison with group II revealed significant differences (p<0.01). Conclusions: AVD extract exhibits an obvious preventive effect on gastrointestinal carcinogenesis induced by MNNG in rats through the regulation of cell proliferation and apoptosis.

• 한국식품영양학회지
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• 제15권1호
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• pp.23-28
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• 2002

감잎의 메탄을 추출물과 이를 극성이 다른 용매로 더욱 불리한 용매별 획분들의 돌연변이 유발 억제효과를 spore rec assay를 이용하여 검토하고 사람의 결장암 세포인 HT-29와 사람의 위암 세포인 AZ-521의 증식에 대한 저해효과를 실험하였다. 감잎의 메탄을 추출물은 spore rec assay에서 N-methyl- N'-nitro-N-nitrosoguanidine(MNNG) 의 돌연변이성을 61% 정도 억제하였으며, 감잎의 메탄을 추출물에서 효과가 있었던 활성물질을 정제하기 위하여 다시 극성이 다른 용매들로 각각 추출하여 얻은 획분 중에서는 헥산, 클로로포름 및 에틸아세테이트 획분이 강한 돌연변이 유발억제효과를 나타내었다. 그리고 감잎의 메탄을 추출물은 암세포의 증식을 억제시키는 항발암 효과가 관찰되었는데 사람의 결장암 세포인 UT-29와 사람의 위암 세포인 AZ-521에 감잎의 메탄을 추출물을 50$\mu\textrm{g}$/ml와 100$\mu\textrm{g}$/ml 첨가시 이들 암세포의 증식이 각각 90%와 99%가지 크게 억제되었다. 감잎의 메탄을 추출물을 다시 극성이 다른 용매들로 분리한 획분들 중에서는 사람의 결장암 세포인 HT-29와 사람의 위암세포인 AZ-521에 감잎의 클로로포름 획분을 각각 50$\mu\textrm{g}$/ml와 100$\mu\textrm{g}$/ml 첨가시 이들 암세포의 증식 억제율이 100%에 달하였고 감잎의 에틸아세테이트 획분도 사람의 결장암 세포(HT-29)와 사람의 위암세포(AZ-521)에 대해 클로로포름 획분 다음으로 강한 항발암 효과가 관찰되었으며, 헥산 획분도 이들 두 획분(클로로포름 및 에틸아세테이트)보다는 낮았으나 암세포 증식을 억제하는 효과가 관찰되어 항돌연변이 실험에서와 일치하는 결과를 얻었다.

• 한국환경성돌연변이발암원학회지
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• 제18권2호
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• pp.71-76
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• 1998

환경독성물질에 의한 폭로는 세포내 DNA의 수복과정에 영향을 미쳐 돌연변이나 암을 유발할 수 있다. 독성물질에 의해 유도된 DNA의 비정상 수복효과를 판단하기 위하여.in vivo에서 MNNG 또는 Benzo(a)pyrene을 투여하고 in vitro에서 Bleomycin을 처리하여 나타나는 염색체이상효과를 관찰하였다. 실험결과, MNNG를 투여 후 Bleomycin을 처리하였을 때 염색체이상의 상승효과가 나타났다. 한편, Benzo(a)pyrene 투여 후 Bleomycin을 처리하였을 패는 높은 농도에서 염색체이상의 상승효과가 나타났다. 이같은 결과는 MNNG나 Benzo(a)pyrene 같은 유전독성물질들이 in vivo에서 세포내 비정상 DNA수복을 일으킬 수 있으며, 이러한 작용은 관련 유전독성물질의 염색체손상성에 무관하며 투여용량에 의존되는 것으로 판단된다.

• 생명과학회지
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• 제11권5호
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• pp.432-438
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• 2001

우리나라 동치미 발효에 관여하는 유산균의 항돌연변이활성을 조사하기 위하여 숙성중의 동치미부터 300여주의 유산균을 분리하였다. 이들 균주들의 항돌연변이활성이 활성을 Salmonella enterotica serovar typhimurium TA100과 TA98을 이용하여 조사하고 직접 변이원 MNNG, NPD, 4-NQO와 간접변이원으로서 AFB1에 대하여 항돌연변이 활성이 가장 우수한 DLAB19균주를 최종 선별하였다. 최종 선별한 DL-AB19의 형태학적, 배양학적 및 생리학적 특성을 조사하여 Bergeys Manual Systematic Bacteriology의 분류 기준에 따라 동정한 결과 Leuconostoc mesenteroides subsp. cremoris 또는 그 유연균으로 동정하였다. Leu. mesenteroides subsp. cremoris DLAB19의 배양 상징액의 MNNG, NPD, 4-NQO 및 AFB1에 대한 항돌연변이 활성은 100$\mu$ι/plate 첨가시활성이 가장 높게 나타났다. 또한 B. subtilis의 포자를 이용한 spore-assay 방법을 사용하여 MNNG와 4-NQO에 대한 항돌연변이 활성을 가지고 있음을 재확인하였다.

• 동아시아식생활학회지
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• 제14권3호
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• pp.288-293
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• 2004

This study was carried out to determine the antimutagenic and anticancer effects of fermented soybean using Ames test and cytotoxicity, respectively. The ethyl acetate fraction (200 g/plate) of fermented soybean in the Salmonella typhimurium TA100 strain showed 86.6% of inhibition rate against the mutagenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG). In addition, the suppression of ethyl acetate fraction with same concentration of fermented soybean in the Salmonella typhimurium TA98 and TAI00 strains showed 82.4% and 90.8% inhibition against 3-amino-l,4-dimethyl-5H-pyrido-(4,3-b)indol (Trp-P-l), respectively. The cytotoxicity effects of fermented soybean against the cell lines with human lung carcinoma (A549), human gastric carcinoma (AGS) and human breast adenocarcinoma (MCF-7) were inhibited with the increase of the extract concentration. The treatment of 1.0 mg/mL ethyl acetate fraction of fermented soybean showed strong cytotoxicities of 71.6%, 91.5% and 80.7% against A549, AGS and MCF-7, respectively.

• Journal of Plant Biology
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• 제30권1호
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• pp.69-77
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• 1987

From the single cell cultures of haploid tobacco (Nicotiana tabacum L. cv. NC 2326) glyphosate-resistant plants were regenerated. After treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and then inoculated onto the LS medium supplemented with 1 mM glyphosate, the single cells survived formed colonies and calluses in 65 and 95 days after culture, respectively, and then whole plants were regenerated in 0.1 mM glyphosate-containing medium from the selected calluses. There was no difference in fresh weight and shikimate content between the selected and normal haploid calluses. When sprayed with 0.1 mM glyphosate, the shikimate contents in the regenerated and normal plants were 0.659 and 20.816 mol/g fr. wt., while that in other normal plants which were not sprayed was 0.921. In addition, the calluses induced from the regenerated plants grew without showing any retardation when treated with glyphosate. These results indicate that the secelcted calluses and regenerated plants are resistant to glyphosate.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.143-143
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• 1993

현재 시판되고 있는 정장용 생균 제제에 함유되어있는 정장 균주의 하나인 Bifidobacterium bifidum은 항결핵제 중 rifampicin에 감수성으로 rifampicin과 병용 투여시 본래의 정장 효과를 기대할 수없다. 따라서, rifampicin에 내성인 돌연변이 균주를 얻기 위해 B. bifidum을 N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)로 처리하여 rifampicin에 내성인 30 종의 균주를 선별하였고, rifampicin에 대한 Minimal Inhibitory Concentration (MIC)를 측정해 본 결과 내성이 1,000 배 이상 상승하였다. 균주 동정을 위하여 fructose-6-phosphate phosphoketolase test를 실시해 본 결과 Bifidobacterium임이 확인되었다. 이들 내성 균주들의 유기산 생산량을 측정하여 그 생산량이 모균주와 가장 유사한 3 종의 균주를 선발하였다. 이들에 대하여 Escherichia coli 생육 억제능을 시험해 본 결과 E. coil 생육 억제능이 모균주와 유사하였다. 또, rifampicin을 함유한 배지에서 돌연변이 균주를 배양시킨 경우 rifampicin이 안정한 상태로 잔존한 것을 알 수 있었다. 이것으로 보아 돌연변이 균주들은 rifampicin을 분해 또는 변형시키는 효소를 생산하지 않는다고 볼 수 있다. 이상의 결과로 본 연구에서 개발한 돌연변이 균주들, 즉 B. bifidum RFRll, RFR21 그리고 RFR61은 rifampicin에 내성이면서 모균주와 동일한 생화학적 특성을 갖는 정장 균주로 여겨진다.

• 한국식품위생안전성학회지
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• 제10권4호
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• pp.219-224
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• 1995

The antimutagenic effects of 46 kinds of medicinal plants that have been used as traditional folk antitumor agents in Korea were studied by using Ames mutagenicity test. Most of the methanolic extracts from the plants which were used in this experiment showed strong antimutagenic activity toward aflatoxin B1(AFB1) in Salmonella typhimrium TA100 and TA98. However, N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) induced mutagenicity was not blocked by adding the methanolic extracts of the plants except persimmon leaves (Diospyros kaki Thunberg)and Elaeagnus umbellata.