• Archives of Pharmacal Research
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• v.22 no.2
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• pp.99-107
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• 1999

A series of organosulfur compounds were synthesized with the aim of developing chemopreventive compounds active against hepatotoxicity and chemical carcinogesis. 2-(Allylthio) prazine (2-AP) was effective in inhibiting cytochrome P450 2E1-mediated catalytic activities and protein expression, and in inducing microsomal epoxide hydrolase and major glutathione S-transferases. 2-AP reduced the hepatotoxicity caused by toxicant sand elevated cellular GSH content. Development of skin tumors, pulmonary adenoma and aberrant crypt foci in colon by various chemical carcinogens was inhibited by 2-AP pretreatment. Anticarcinogenic effects of 2-AP at the stage of initiation of tumors were also observed in the aflatoxin B1 ($AFB_1$)-induced three-step medium-term hepatocarcinogenesis model. Reduction of $AFB_1$-DNA adduct by 2-AP appeared to result from the decreased formation of $AFB_1$-8,9-epoxide via suppression of cytochrome P450, while induction of GST 2-AP increases the excretion of glutathione-conjugated $AFB_1$ . 2-AP was a radioprotective agent effective against the lethal dose of total body irradiation and reduced radiation-induced injury in association with the elevation of detoxifying gene expression. 2-AP produces reactive oxygen species in vivo, which is not mediated with the thiol-dependent production of oxidants and that NF-KB activation is not involved in the induction of the detoxifying enzymes. the mechanism of chemoprotection by 2-AP may involve inhibition of the P450-mediated metabolic activation of chemical carcinogens and enhancement of electrophilic detoxification through induction of phase II detoxification enzymes which would facilitate the clearance of activated metabolites through conjugation reaction.

• Korean Journal of Agricultural Science
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• v.48 no.1
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• pp.73-81
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• 2021

The current study investigated how Saccharomyces cerevisiae ameliorates the adverse effects of aflatoxin on in vitro rumen fermentation. In this study, five groups (T₁: Control [basal feed]; T₂: T₁ + 300 ppb aflatoxin B1 [AFB₁] and T₃, T₄, and T₅: T₂ with 0.05, 0.1, and 0.2% of S. cerevisiae, respectively) were prepared and incubated in vitro. The results revealed that truly degradable dry matter (TDDM), gas production (GP), microbial biomass production (MBP), truly degradable organic matter (TDOM), partitioning factor (PF), total volatile fatty acids (TVFA), acetate (A), propionate (P) and butyrate (B) values in the control group (T₁) were higher (p < 0.05) than those of the AFB₁ fed group (T₂). The A : P ratio in the control group (T₁) was reduced (p < 0.05) when compared to that of the T₂ group. The TDDM, TDOM, GP, TVFA, A, P, and B values of T₃, T₄, and T₅ improved with the increasing levels of S. cerevisiae; however, the values of group T₅ were lower (p < 0.05) than that of the control. The values of MBP, A : P ratio and PF in group T₅ were statistically similar to that of the control. It was concluded that the inclusion of S. cerevisiae (0.05 to 0.20%) to the AFB₁ (300 ppb) contaminated feed partially to completely ameliorated the adverse effects of AFB₁ on the in vitro rumen fermentation parameters.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.274-279
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• 2001

Generally, non-aflatoxigenic fungi, such as Aspergillus oryzae, and Aspergillus are main microflora in Korean traditional fermented foods including Meju and soybean paste, but sometimes, Aspergillus flavus and Aspergillus parasiticus can be contaminated and accumulated aflatoxins during fermentation and storage. So the screening of aflatoxigenic strains in fermented traditional food is very important to improve the sanitary quality of those foods. In this work, we screened aflatoxin producing fungi from commercial Meju and soybean paste in Western Gyeongnam by immunoassay. Samples were randomly purchased from market of the commercial Meju(10 EA) and soybean paste(20 EA) in nine areas of Western Gyeongnam. Of the samples collected,24 strains and 22 strains of Aspergillus sp. were isolated from Meju and soybean paste, respectively. The isolated strains were cultured on SLS media at $25^{\circ}C$ for 15 days. The cultured broth were extracted with ethyl acetate and were analysed to determine aflatoxin B$_1$(AFB$_1$) by direct competitive ELISA(DC-ELISA). Six strains(25%) isolated from Meju, and 2 strains(9%) isolated from saybean paste, were confined as aflatoxin producing strains. The average range of aflatoxin productivity of isolates from Meju was 54.6 $\pm$ 38.7 ng/ml and that from soybean paste was 11.1 $\pm$ 8.6 ng/ml, respectively. Among them, isolated strain No. M-5-4 produced a high level of AFBl and showed 98.26 ng/ml of AFB$_1$. Every isolates were also re-confined their AFB$_1$productivity by thin layer chromatography(TLC). The TLC results also showed same trend as DC-ELISA results. As the above results, the screening of hazard mycotoxigenic fungi from traditional fermented foods should be necessary for the safety and the application of HACCP system in the food manufactory in Korea.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.188-194
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• 1994

The inhibitory effects of rice extract on mutagenicity induced by 3-amino-1,4-dimethyl-5H-pyrido [4,3-b]indole(Trp-P-1), 3-amino-1-methyl-5H-pyrido [4,3-b]indole(Trp-P-2), sodium azide(SA), 2-nitrofluorene(2NF), mitomycin C(MMC), aflatoxin $B_1(AFB_1)$ and 4-nitroquinoline oxide(4-NQO) were investigated using Salmonella typhimurium reversion assay, SOS chromotest and spore rec-assay. In Salmonella typhimurium reversion assay, methanol extract from brown rice (Illpumbyeo, Japonica variety) showed the highest inhibitory effect among other extracting solvent including hexane, chloroform and water. Methanol extract showed stronger inhibitory effect, above 85%, on indirect-acting mutagens(Trp-P-1, Trp-P-2 and $AFB_1$) than those on direct-acting mutagens(4-NQO, 2NF). In SOS chromotest, methanol extracts showed $77.6{\sim}88.9%$ effects on SOS function induced by Trp-P-1, Trp-P-2, $AFB_1$ and 4-NQO. In spore rec-assay, methanol extracts inhibited the mutagenicity induced by $AFB_1$ and MMC. As the concentration of methanol extract increased, inhibitory effect on mutagenicity increased but reached at steady state as inhibition rate of 90% when the concentration was above 5 mg/plate. In inhibitory effects of methanol extracts by various rice varieties, all of 11 varieties turned out to have inhibitory effect on mutagenicity. There was no significant difference (p>0.05) in inhibitory effect of methanol extracts between brown and white rice against Trp-P-1, but showed difference (p<0.05) against 4-NQO.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.468-472
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• 1995

Substantial amount of caryophyllene oxide (CPO) is present in the essential oils of traditionally-used folk medicinal plants and herbal spices. The CPO, produced via chemical and/or enzymatic reaction of caryophyllene (CP), has largely being used as a flavoring component and exhibited a variety of biological activities. Now, we report the antimutagenic activity of CPO determined by Ames's preincubation test. S-9 fraction was prepared from the liver of rats treated with Arochor 1254. Anatoxin $B_1\;(AFB_1)$ and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) were used as mutagens. Reduction of mutagenicity of $AFB_1$ or IQ for S. typhimurium TA98 and TA100 by CPO was found to be a dose-dependant manner. CPO (500 ${\mu}g/plate$) reduced mutagenicity of AEB1 for S. typhimurium TA98 and TA100 to 89% and 71%, respectively. For IQ, similar results were observed against S. typhimurium TA98 and TA100, resulting in the inhibition percentage of 77% and 51%, respectively. CP also reduced mutagenicity of AEB1 and IQ for S. typhimurium TA98 and TA100, but the reduction rate was somewhat lowered relative to that of CPO. These results indicate that CPO could be developed as a potent antimutagenic flavoring agent.

• The Korean Journal of Cytopathology
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• v.1 no.1
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• pp.68-73
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• 1990

A total of 48 cases of tuberculous lesion in the lymph nodes (43 cases), lung (3 cases) and soft tissue (2 cases), was subjected to fine needle aspiration cytology (FNAC). The age of the patients ranged from 19 to 77 year-old (average 33.6 years in age) and the male to female ratio was 1 : 4. Thirty-four cases (70.8%) demonstrated distinct granulomatous reaction with or without caseation necrosis, nine cases (18.8%) showed no granulomas, but large amount of necrotic debris with numerous polymorphonuclear cells and histiocytes, and five cases (10.4%) revealed acellular material only. The overall AFB positivity in smears was 62.5%. In areas associated with granulomatous reaction and necrosis, AFB positivity was 55.8%, while it was 80.0% in cases with acellular necrotic material. There were 2 cases of parasitic infestation which could not be easily differentiated from tuberculosis based on aspiration smears only.

• Preventive Nutrition and Food Science
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• v.2 no.4
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• pp.348-353
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• 1997

The antimutagenic and cancer cell growth inhibitory effects of methanol extracts from 9 kinds of seaweed were studied in the Ames assay and cell culture systems, respectively. The methanol extracts from the seaweeds of sea lettuce, chlorella, sea tangle, sea mustard, sporophyll of sea mustard, fusiforme, seaweed papulosa, purple laver and ceylon moss showed antimutagenicities against aflatoxin B₁(AFB₁) and N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) in the Salmonella typhimurium TA100. These extracts revealed relatively higher antimutagenicity against AFB₁(indirect mutagen) than MNNG(direct mutagen). Sporophyll of sea mustard and seaweed papulosa exhibited strong antimutagenic activity against AFB₁, and sporophyll of sea mustard, sea tangle and ceylon moss also reduced the mutagenicity induced by MNNG. The sporophyll fo sea mustard exerted the highest antimutagenic activity among the samples treated. The methanol extracts from 9 kinds of seaweed inhibited the growth of two cancer cell lines, AGS human gastric adenocarcinoma cells and HT-29 human colon carcinoma cells. Sea tangle, sea mustard and sporophyll of sea mustard inhibited the growth of cancer cells significantly. These results suggest that various seaweeds show not only antimutagenic activity but also growth inhibitory effect of some cancer cells.

• Journal of Magnetics
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• v.13 no.1
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• pp.19-22
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• 2008

ZnO nanotips, grown on c-$Al_2O_3$ and quartz, were implanted variously with 200 keV Fe or Mn ions to a dose level of $5{\times}10^{16}cm^{-2}$. The magnetic properties of these samples were measured using a superconducting quantum interference device (SQUID) magnetometer. Fe-implanted ZnO nanotips grown on c-$Al_2O_3$ showed a coercive field width of 209 Oe and a remanent field of 12% of the saturation magnetization ($2.3{\times}10^{-5}emu$) at 300K for a sample annealed at $700^{\circ}C$ for 20 minutes. The field-cooled and the zero-field-cooled magnetization measurements also showed evidence of ferromagnetism in this sample with an estimated Curie temperature of around 350 K. The Mn-implanted ZnO nanotips grown on c-$Al_2O_3$ showed superparamagnetism resulting from the dominance of a spin-glass phase. The ZnO nanotips grown on quartz and implanted with Fe or Mn showed signs of ferromagnetism, but neither was consistent.

• Tuberculosis and Respiratory Diseases
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• v.74 no.5
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• pp.215-221
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• 2013

Background: Nontuberculous mycobacteria (NTM) are considered opportunistic pathogens, and several species of NTM are associated with human diseases that typically involve the pulmonary, skin/soft tissue, or lymphatic systems; such infection may also cause disseminated diseases. Recent studies have reported increasing rates of NTM-induced disease worldwide. Methods: Respiratory samples are being analyzed for acid-fast bacilli (AFB) culture and NTM identification at Dankook University Hospital in Cheonan, Korea, from September 2005 to September 2011. Identification is performed by using polymerase chain reaction-restriction fragment length polymorphism analysis targeting a novel region of the rpoB gene. Results: A total of 25,133 specimens were received for AFB culture, of which 1,014 (4.0%) were NTM-positive. A total of 267 samples from 186 patients were tested for NTM identifications, and 232 samples from 157 patients were positive for NTM species. Among the patients who tested positive for NTM, 65.6% were men and the average age was 63.3 years. Mycobacterium avium complex, the most commonly detected NTM pathogen, was found in 65.9% of the 232 samples. The annual average percentage of NTM isolates from AFB culture-positive specimens was 31.3%: the highest rate was seen in 2011 (44.3%), followed by 2009 (37.4%) and 2010 (37.2%). An upward trend in NTM incidence was found during the study period. Conclusion: The prevalence of pulmonary NTM isolates continues to increase in Cheonan, suggesting that pulmonary NTM disease is becoming increasingly common.

• Natural Product Sciences
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• v.4 no.2
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• pp.100-104
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• 1998

The antimutagenic activity of a methanol extract of roasted Cassia tora seed against aflatoxin $B_1(AFB_1)$ was demonstrated with the Salmonella typhimurium assay. The numbers of revertants per plate decreased significantly when this extract was added to the assay system using Salmonella typhimurium TA100 and or TA98. The MeOH extract was then sequentially partitioned with $CH_2Cl_2$, EtOAc, n-BuOH, and $H_2O$. The $CH_2Cl_2$ and n-BuOH fractions possessed antimutagenic activity, but the EtOAc and $H_2O$ fractions were inactive. Both the MeOH extract and its fractions were capable of inhibiting the indirect-acting mutagen $AFB_1$, suggesting that these fractions may prevent the metabolic activation of $AFB_1$, or scavenge the electrophilic intermediate capable of inducing mutations. Column chromatography using silica gel yielded pure alaternin from the $CH_2Cl_2$ a fraction, and adenosine and isorubrofusarin gentiobioside from the n-BuOH fraction. Alaternin and isorubrofusarin gentiobioside demonstrated significant antimutagenic activities.