• Food Science and Preservation
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• v.11 no.3
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• pp.405-410
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• 2004

Leuconostoc mesenteroides subsp. cremoris DLAB19 were investigated under various culture conditions to maximize the production of antimutagenic substance(s) against aflatoxin Bl(AFBl) on Salmonella enterica serovar Typhimurium TAI00 and TA98. The MRS medium containing glucose(2$\%$) as a carbon source and yeast extract(1 $\%$) as a nitrogen source resulted in the highest production of the antimutagenic substance(s) against aflatoxin Bl(AFBl) in the culture supernatant of Leu. mesenteroides subsp. cremoris DLAB19. Optimal pH of the medium, culture temperature and shaking speed for the antimutagenic substance(s) production were pH 7.0, 30$^{\circ}C$ and 150 rpm, respectively. Under the optimal condition, the antimutagenic effects of Leu. mesenteroides subsp. cremoris DLAB19 culture supernatant were 87.11 $\%$ on S. enterica serovar Typhimurium TA100 and 75.04 S. enterica serovar Typhimurium TA98.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.11
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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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• v.25 no.2
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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.

• Korean Journal of Veterinary Service
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• v.22 no.4
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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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• 2003.10a
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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.

• YAKHAK HOEJI
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• v.49 no.6
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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.

• Food Science and Preservation
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• v.8 no.4
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• pp.399-404
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• 2001

Antimutagenic, antioxidative and nitrite-scavenging effects of seafood bun were investigated. Each samples were extracted with methanol. Aflatoxin Bl(AFB1) was used as mutagen. Seafood bun added 20% kimchi(5mg/plate) reduced mutagenicity of AFB1 for Salmonella typhimurium TA and YG 1024 to 47% and 61%, rrespectivery. The reduction rate of seafood bun added 20% kimchi was higher relative to that of other samples. Mydrogen donating activity in all buns showed over 50% and seafood bun added 20% kimchi was higher than others, but the activity was lower than that of 0.1% BHT. The peroxide value for linoleic acid increased during the storage, the values in seafood bun added 20% kimchi was higher than others, but the activity was lower than that of 0.1% BHT. The peroxide value for linoleic acid increased during the storage, the values in seafood bun added 20% kimchi was significantly lower and the values in other buns were a lower than that of control, the values in all of the samples were higher than that in 0.1% BHT. Among the samples tested, the TBA value in the seafood bun added 20% kimchi for liver homogenate of rat was the lowest. Nitrite-scavenging effect in all the samples tested was higher than 50%.