• International Journal of Industrial Entomology and Biomaterials
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• v.44 no.2
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• pp.65-71
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• 2022

The wild silkmoth Antheraea yamamai Guérin-Méneville, 1861 (Lepidoptera: Saturniidae) is an important producer of silk that is superior to the silk produced by traditional domesticated silkworm. In this study, we sequenced the complete mitochondrial genome (mitogenome) of An. yamamai collected from Jeju Island, which is the southernmost island approximately 100 km offshore southward from the Korean Peninsula. Determining this sequence will be necessary for tracing the biogeographic history of the species and developing molecular markers for identifying the origin of commercial products. Comparison of the sequence divergence among two available and the current mitogenomes revealed a low but substantial number of substitutions, totaling 23 nucleotides in the whole genome. CytB and ND5 showed the highest variability with five and four variations, respectively, suggesting that these regions will be prior regions to target for subsequent biogeographic and diagnosis study. Phylogenetic reconstruction based on all available sequences of Saturniidae showed that An. yamamai is a sister to the congeneric species An. pernyi, corroborating that Antheraea is a highly supported monophyletic group. The tribe Saturniini was clearly non-monophyletic and interrupted by Attacini and Bunaeini.

• Journal of Food Hygiene and Safety
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• v.38 no.4
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• pp.217-227
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• 2023

The consumption of ready-to-eat side dishes is rapidly growing in South Korea. These foods are particularly vulnerable to microbiological contamination as they are often cooked without any treatment, such as heating or stored at room temperature after cooking. Hence, in 2022, we analyzed the ready-to-eat side dishes sold in Gyeongsangnam-do, South Korea for microbiological contamination. We collected 100 samples from supermarkets in 7 cities, and then examined them for presence of food-borne pathogens and sanitary indicator bacteria. In the analysis of the food-borne pathogens, Bacillus cereus and Clostridium perfringens were isolated from 51 samples (51.0%) and 3 samples (3.0%), respectively. However, both quantitatively met the Korean Food Standards Codex. Genes of five different enterotoxins and one emetic toxin were analyzed from the 51 isolated B. cereus strains. We detected enterotoxin entFM (100.0%), nheA (94.1%), hblC (58.8%), cytK (56.9%), and bceT (41.2%) in 51 isolates, and emetic toxin gene, CER, in only one (2.0%) isolate. We did not detect C. perfringens toxin gene (cpe) that causes food poisoning in any one of the three C. perfringens isolates. In the case of sanitary indicator bacteria, Kimchi had the highest levels of total aerobic bacteria and coliforms, followed by Saengchae, Jeotgal, Jeolim, Namul, and Jorim, respectively. We counted total aerobic bacteria at two different storage temperatures (4℃ and 20℃) to determine the effect of storage temperature. When stored at 20℃, total aerobic bacteria count increased in most of the ready-to-eat side dishes, except for Jeotgal. This result conclusively shows the need for refrigerating the ready-to-eat side dishes after purchase. Further research is needed to assess the risk and safety of the ready-to-eat side dishes available in the market and determine appropriate safety management practices.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.334-340
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• 2014

Toxin-producing Bacillus cereus is the causative agent of two different types of food poisoning: the emetic and the diarrheal types. This study was conducted to investigate the presence of enterotoxin and emetic toxin genes in 263 B. cereus isolated from 619 different ready-to-eat food items. Hemolytic enterotoxins hblA, hblC, and hblD were detected in 85.6, 41.1, and 76.8%, respectively, of the B. cereus isolates. About 67.0% (175/263) of the isolates presented all of three genes. Non-hemolytic enterotoxins nheA, nheB, and nheC were detected in 100, 97.0, and 68.4% of the isolates, respectively. Approximately 90.0% (236/263) of the isolates presented all of these three non-hemolytic enterotoxin genes. Emetic toxin gene, CER, was detected in 132 of 263 (50.2%) isolates. Computer-assisted cluster analysis of Rep-PCR profiles showed a high genetic diversity among the isolates. All B. cereus isolates from food samples tested in this study carried at least 6 of 10 toxin genes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.12
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• pp.1895-1904
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• 2015

Foodborne illness associated with food service establishments is an important food safety issue in Korea. In this study, foodborne pathogens (Bacillus cereus, Clostridium perfringens, Escherichia coli, pathogenic Escherichia coli, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and Vibrio parahaemolyticus) and hygiene indicator organisms [total viable cell counts (TVC), coliforms] were analyzed for food and environmental samples from foodservice establishments at schools in Gyeonggi province. Virulence factors and antimicrobial resistance of detected foodborne pathogens were also characterized. A total of 179 samples, including food (n=66), utensil (n=68), and environmental samples (n=45), were collected from eight food service establishments at schools in Gyeonggi province. Average contamination levels of TVC for foods (including raw materials) and environmental samples were 4.7 and 4.0 log CFU/g, respectively. Average contamination levels of coliforms were 2.7 and 4.0 log CFU/g for foods and environmental swab samples, respectively. B. cereus contamination was detected in food samples with an average of 2.1 log CFU/g. E. coli was detected only in raw materials, and S. aureus was positive in raw materials as well as environmental swab samples. Other foodborne pathogens were not detected in all samples. The entire B. cereus isolates possessed at least one of the diarrheal toxin genes (hblACD, nheABC, entFM, and cytK enterotoxin gene). However, ces gene encoding emetic toxin was not detected in B. cereus isolates. S. aureus isolates (n=16) contained at least one or more of the tested enterotoxin genes, except for tst gene. For E. coli and S. aureus, 92.7% and 37.5% of the isolates were susceptible against 16 and 19 antimicrobials, respectively. The analyzed microbial hazards could provide useful information for quantitative microbial risk assessment and food safety management system to control foodborne illness outbreaks in food service establishments.

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.21-26
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• 1984

The balance between metabolic activation of xenobiotics and detoxification of their active metabolites may playa vital role in controlling mutagenic and carcinogenic processes. To assess the possible role of P. ginseng C.A. Meyer in detoxification of xenobiotics, we studied the effects of ginseng on several parameters of the monooxygenasd system, including benzo(a) pyrene monooxygenase(AHH) and benzo(a) pyrene epoxide hydratase(EH) as well as effects of ginseng on the conjugation system. Test animals receiving ginseng saponin-fraction induced epoxide hydratase activity to over $150\%$ (20mg/kg b.w.) of the control and increased glutathione transferase activity (GSH-T) up to $140\%$ (20mg/kg b.w.) of the control, whereas no significant changes were observed in the benzopyrene monooxygenase activity (AHH). Such a selective induction of the inactivation enzyme epoxide hydratase, combined with a marked elevation of the detoxifying enzyme glutathione transferase, without a concurrent induction of benzopyrene monooxygenase which is responsible for the formation of carcinogenic intermediates, demonstrates that ginseng has the potential to alter the metabolic course of carcinogenic polycyclic aromatic hydrocarbons, and thereby enhance detoxification. Thus, ginseng may play an important role in the prevention of tumors caused by carcinogens.

• Journal of Ginseng Research
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• v.13 no.1
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• pp.42-48
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• 1989

The binding of bay region diol-epoxides of polycyclic aromatic hydrocarbons (PAHs) to target tissue DNA is thought to be essential for the initiation of cancer by these compounds. In this study we investigated the effect of polyacetylenes such as panaxynol and panaxydol on the formation of benzo(a)pyreno (BP)-metabolite-DNA adduct in the liver of ICR mice. Treatment of mice by i.p. administration of polyacetylenes produced a marked reduction in BP metabolite binding to DNA in vitro. Following i.v. administration of (3H)BP(300, ${\mu}$Ci/21 nmoles/0.1 nt DMSO) to mice, radioactivity was detected in the DNA of the liver in vivo. The result of tentative identification of the 4 peaks between the two standard markers for high pressure liquid chromatography showed that the peaks. I, II, III, and IV were BP-phenol oxide-DNA adduct (or BP-diol-epoxide-dCyt. adduct), (-) BP$.$diolepoxide I:dGuO adduct, (+) BP-diol-epoxide I: dGuo adduct, and BP-diol-epoxide II:dGuO adduct, respectively. The minor adduct, (-) BP-diol epoxide I: dGuo was reduced to 6971 of the amount of the control, while the major adduct, (+) BP-diolepoxide I: dGuO(peak II) which was produced from (-) BP-7, 8-diol was reduced to 78% of that of the control. The amount of the minor adduct, BP-diol-epoxide II:dGuo adduct(peak IV) which formed from (+) BP-7, 8-diol was 58% of the control. These results show that the panaxydol is more related to inhibition of the formation of the minor ad- ducts than of the major adducts, which were generally produced from ($\pm$) BP-7, 8-dihydro-dials.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.141-147
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• 2023

The genus Cottiusculus Jordan and Starks 1904 (Cottoidei: Cottidae) comprises four species worldwide, three species in Japan, and two species in Korea. Cottiusculus species are characterized by a compressed head and body without scales, except for lateral-line scales, a preopercle with four spines, a curved uppermost preopercular spine with small dorsal spines, and teeth on the upper jaws, vomer, and palatines. Two Cottiusculus species have been recorded in Korea: Cottiusculus gonez and Cottiusculus nihonkaiensis. Among these, "jeom-jul-hoet-dae" specimens were initially identified as Cottiusculus schmidti by many Korean Ichthyologists. However, since C. nihonkaiensis was reported by Kai and Nakabo (2009), most such specimens have been identified as C. nihonkaiensis. To clarify the taxonomic status of "jeom-jul-hoet-dae", we conducted morphological and molecular analyses collected from the coasts of South Korea, and compared our findings with previous reports. Japanese and Korean C. nihonkaiensis specimens mostly consistent in some proportional measurements, our molecular results indicate that they are the same species. C. nihonkaiensis, "jeom-jul-hoet-dae" distinguished from other congers by combination of following characters: simple nasal spines, two branched cirri at the upper jaw, cirri at the opercular, preopercular, and lateral lines, and a number of blotches below the lateral line.