• 한국식품저장유통학회지
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• 제11권3호
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• pp.405-410
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• 2004

동치미에서 분리한 유산균인 Leu. mesenteroides subsp.cremoris DLAB19 균주의 aflatoxin Bl에 대한 항 돌연변이원성 물질 생산을 위한 최적 조건을 조사한 결과, 탄소원으로 glucose를 첨가시 가장 높은 항 돌연변이 효과를 나타내었으며, 질소원으로서는 yeast extract 첨가시 항 돌연변이 효과가 우수하였다. 탄소원으로 glucose의 농도을 2$\%$ 첨가시aflatoxin Bl에 대한 항 돌연변이 효과가 가장 우수하였으며,질소원으로서 yeast extract 1$\%$ 첨가시 가장 우수한 항 돌연변이 효과를 나타내었다. 항 돌연변이원성 물질 생산을 위한 최적 배양 조건은 초기 pH, 배양 온도, 진탕 속도가 각각 7.0, 30$^{\circ}C$ 및 150 rpm이었다. 상기의 최적 조건에서 36시간 배양시 가장 높은 항 돌연변이 효과를 나타내었는데 S. enterica serovar Typhimurim TA100과 TA98을 이용한 경우항 돌연변이 효과가 87.11$\%$와 75.04$\%$이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권11호
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• pp.1509-1517
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• 2004

A study was conducted to determine the safety of feeding processed broiler litter (BL) to beef cattle. The litter was processed by deepstacking, ensiling and composting. The health issues addressed relevant to the safety of feeding litter included pathogenic bacteria, mycotoxins, heavy metals, medicinal drugs and pesticide residues. Exp. 1 evaluated the feed hygiene of processed rice hulls-bedded BL. The presence of pathogenic bacteria in BL was determined before and after deepstacking. A total of 21 BL samples were collected over a 3-year period of commercial and experimental production of BL for beef cattle. Exp. 2 evaluated the safety of meat of cattle fed deepstacked BL. In Exp. 1, there were no pathogenic bacteria, such as coliform, E. coli, E. coli O157:H7, Salmonella, Listeria and Proteus, in deepstacked BL. Levels of heavy metals (Cu, Fe, Mn and Zn) and toxic heavy metals (As, Pb, Cd and Hg) were lower than the commercial feed tolerances. Aflatoxin, medicinal drug and pesticide residues were detected at extremely low levels. In Exp. 2, the meat of the BL-fed animals exhibited few differences in all analyzed items from that of the control group, showing safety from pathogenic microorganisms and heavy metals. When BL was withdrawn for 14 days prior to slaughtering the BLfed cattle, no medicinal drug residues were detected in the meat. Pesticides in the tissues of either group of animals were much lower than the tolerances. In conclusion, processed rice hulls-bedded BL and the meat of cattle fed BL were safe from the potential hazards of pathogenic bacteria, heavy metals, aflatoxin, medicinal drugs and pesticide residues.

• Parasites, Hosts and Diseases
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• 제25권2호
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• pp.99-109
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• 1987

The present study was carried out to examine the effect of a calcinogen, aflatoxin B1 on the ultrastructural changes of ciliary epithelial cells in mice infected with Clonerchis sinensis. A total of 93 male albino mice(BALB/c strain) was divided into 3 groups; group I, treated with 1.0 ppm aflatoxin Bl for 12 weeks; group II, given 50 C. sinensis n;etacercariae, and group III, given 50 metacercariae and treated with 1.0 ppm aflatoxin Bl for 12 weeks. Three mice served for untreated-uninfected controls. From 4 weeks after the treatsment and/or in(ection, three mice from each group were sacrificed at 4 week intervals up to the 40th week, and their hepatobiliary tissues were prepared for transmission electron microscopy. The most prominent ultrastructural changes in group I were remarkable enlargement of nuclear size, separation of nucleolus, dispersed chromatin granules in nuclei and increased dense granules along the inner membrane of nuclei. In the cytoplasm there was slight proliferation of mitochondria and endoplasmic reticulum (ER) at earlier stage. At the 12th week separation of fibrillar and granular components of the nucleolus was a characteristic finding. As the time elapsed, epithelial cells showed fiattened-cuboidal form and a tendency of atrophy. Most of the nuclei were elongated and polygonal in shape. In group II the appearance of elaborate interwoven folds of lateral cytoplasm forming a labyrinth of interconnected intercellular space and variety in nuclear shape were the prominent fadings at earlier stage. The cytoplasm showed slight proliferation and dilatation of mitochondria and ER, and a small number of mucin droplets. In the basement membrane scanty fibrous cells were seen. With time, variety in nuclear shape, marked proliferation and dilatation of rough ER and some collagen fibrils were demonstrated. Other features of intracellular organelles and mucin droplets persisted. In group III cuboidal epithelial cells showed their remarkably enlarged and irregular nuclei, increased chromatin granules in the nuclei, separated nucleoli, proliferated and dilated rough ER. With time, sequestered mitochondria showed blob-like evaginations which lacked cristae and dense matrix, and were limited by a single membrane. Since the 20th week, microvilli were relatively scanty and poorly developed. Organelles and inclusions in the cytoplasm of metaplastic cells were poor. Nuclei were variable in shape. The nlost prominent changes at later stage were separation of nuclei from the cytoplasm, and appearance of numerous and irregularly angled electron dense granules in the nuclei.

• 한국동물위생학회지
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• 제22권4호
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• pp.393-398
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• 1999

This case occurred following accidental consumptions of toxic levels of feedstuffs in the Korean indigenous cattle which were pregnant for 3-6 months. Grossly, poorly defined bluish coloration in the ventral sac of the rumen, reticulum and omasum was visible on the surface of the stomach. The severely affected ruminal walls were perforated and blood-tinged exudate was observed and death followed due to acute diffuse peritonitis. There were copious amount of porridgelike rumen contents, which has a distinct fermentative odor. The epithelia were easily wiped off and hyperemic in patch. Histopathologically, chemical rumenitis with neutrophilic infiltration and opportunistic fungal infection was evident in the mucosa and submucosa. Multifocal necrotic foci with fungal hyphae on the liver and severe congestion on the renal medulla were noted. There was no evidence of heavy metal and aflatoxin Bl in the suspected feedstuffs. This case was diagnosed as acute carbohydate engorgement in cattle.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.263-267
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• 2003

Solid-state fermentation of lovastatin by Aspergillus terreus was investigated using commercially available 1.2 L polypropylene bottle designed for mushroom cultivation. Moist solid raw materials such as com, rice, and soy bean were tested and com was found to be most suitable for an economical production of lovastatin. 50% or higher water addition prior to the sterilization of com was effective for the maximal lovastatin production. About 0.5% (w/w) lovastatin content in dried cells and corn mass was obtained after 20 days of solid-state fermentation at 30$^{\circ}C$. For safety concerns, aflatoxin Bl and citrinin levels after fermentation were assayed but they were not detected. Lovastatin containing cells and corn residue after fermentation were autoclaved, dried, crushed, and fed to chicken for a period of 3 weeks. Approximately 20% reduction of blood cholesterol level of chicken was observed.

• 약학회지
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• 제49권6호
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• pp.505-510
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• 2005

Allylthio group of allicin and other organosulfur compounds which are isolated from garlic is considered as a pharmacophore, a key structure component of the molecule which is responsible biological activities. In the foregoing studies various 3-allylthio -6- alkoxypyridazine derivatives (K- compounds ) and 3-allylthio -6- alkylthiopyridazine derivatives(Thio-K-compounds) were synthesized and their biological activities were tested in vivo. They showed good hepatoprotective activities on the carbon tetrachloride-treated mouse and aflatoxin Bl-treated rat and chemopreventive activities on bepatocarcinoma cells in rat as expected. Now 3-allylthio-6-heterocyclylalkylaminopyridazine derivatives that the oxygen atom at 6-Position of 3-allylthio-6-alkoxypyridazine is replaced by nitrogen (N) were synthesiz ed and their activities were tested in vitro against SK-Hep-1 human liver cancer cells. They showed good chemopreventive activities on hepatocarcinoma cells.

• 한국식품저장유통학회지
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• 제8권4호
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• pp.399-404
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• 2001

김치 첨가 해물만두의 생리기능성을 조사하고자 시판 만두, 해물만두 및 20% 김치첨가 해물만두 추출물에 대한 항돌연변이, 항산화 효과 및 아질산염 소기능에 대하여 조사하였다. 간접돌면변이원으로 알려진 aflatoxin B$_1$을 첨가한 Salmonella typhimurium TA 100 및 YG 1024에 만두 추출물을 5 mg/plate 농도로 처리한 후 항돌연변이 효과를 조사한 결과 20% 김치첨가 해물만두의 돌연변이 저해율이 47% 및 61%로 가장 높게 나타났으며, 수소공여능은 모두 50% 이상의 활성을 나타내었고, 시판만두, 해물만두 및 20% 김치첨가 해물만두의 순으로 높게 나타났으나, 모두 0.1%의 BHT 첨가군 보다는 낮았다. Linoleic acid에 대한 과산화물가는 저장기간이 지남에 따라 대조군의 과산화물가는 크게 증가한 반면 20% 김치첨가 해물만두 첨가군에서는 대조군에 비하여 매우 낮게 나타났으며, 시판 및 해물만두 추출물의 경우는 약간 낮게 나타났으나 0.1% BHT 첨가군보다는 모두 높았다. 횐쥐의 liver homogenate에 만두추출물을 처리한 후 TBA가를 조사한 결과 20% 김치첨가 해물만두 추출물 처리구가 가장 낮게 나타났다. 아질산염 소거능은 모두 50% 이상이었다.