• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.666-674
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• 2016

The bacterial strains were screened as potential starters for fermenting low-salt doenjang (a Korean traditional fermented soybean paste) using Korean doenjang based on proteolytic and antipathogenic activities under 6.5-7.5% NaCl conditions. Phylogenetic analysis based on 16S rRNA gene sequences showed that they all belonged to the genus Bacillus. Proteolytic and antipathogenic activities against Escherichia coli, Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, and Aspergillus flavus, as well as fibrinolytic, amylase, and cellulase activities of the 10 strains were quantitatively evaluated. Of these, strains D2-2, JJ-D34, and D12-5 were selected, based on their activities. The functional, phenotypic, and safety-related characteristics of these three strains were additionally investigated and strains D2-2 and D12-5, which lacked antibiotic resistance, were finally selected. Strains D2-2 and D12-5 produced poly-γ-glutamic acid and showed various enzyme activities, including α-glucosidase and β-glucosidase. Growth properties of strains D2-2 and D12-5 included wide temperature and pH ranges, growth in up to 16% NaCl, and weak anaerobic growth, suggesting that they facilitate low-salt doenjang fermentation. Strains D2-2 and D12-5 were not hemolytic, carried no toxin genes, and did not produce biogenic amines. These results suggest that strains D2-2 and D12-5 can serve as appropriate starter cultures for fermenting low-salt doenjang with high quality and safety.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.1005-1012
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• 2009

Lysozyme and the reduction of metabisulfite addition to red wine were evaluated during a winemaking process and after malolactic fermentation (MLF). Treatment, with lysozyme, of the must from Tempranillo grapes and at the end of alcoholic fermentation (AF) caused the 100% implantation of the inoculated bacterial strain and shortened the duration of MLF by 7 days. At the end of the MLF, wines treated with lysozyme showed lower volatile acidity, color intensity, and biogenic amine content. The differences in color intensity disappeared during wine stabilization. The lysozyme addition after MLF led to lower histamine concentrations in wines. These phenomena occurred irrespective of the lactic acid bacteria (LAB) proliferation control and of the Oenococcus oeni dominant strain identified at this period. The results of this study show the significance of preventive use of lysozyme in vinification of red wine to maintain low histamine levels and ensure a successful implantation of inoculated O. oeni starters.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.351-360
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• 2020

Previous studies have suggested that microbial fermentation is an attractive process to develop food products using seaweed. The objective of this study was to isolate and characterize lactic acid bacteria (LAB), which are used as starters for seaweed fermentation. The isolation of LAB strains was conducted using kelp Saccharina japonica kimchi, a well-known fermented seaweed in southeastern Korea. Based on the assay of acid tolerance, bile tolerance and antioxidant activity, 15 strains of LAB were selected for further study. The LABs exhibited cholesterol lowering activity in the range of 15.50 to 94.77%. Among the LABs suitable for food production, Lactobacillus plantarum D-11 had the highest antioxidant and cholesterol lowering activities. This probiotic strain will be applied to develop various kelp fermentation products.

• Mycobiology
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• v.44 no.3
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• pp.155-161
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• 2016

The most economically important species used in a wide range of fermentation industries throughout Asia belong to Aspergillus section Flavi, which are morphologically and phylogenetically indistinguishable, with a few being toxigenic and therefore a major concern. They are frequently isolated from Korean fermentation starters, such as nuruk and meju. The growing popularity of traditional Korean alcoholic beverages has led to a demand for their quality enhancement, therefore requiring selection of efficient non-toxigenic strains to assist effective fermentation. This study was performed to classify the most efficient strains of Aspergillus section Flavi isolated from various types of traditional wheat nuruk, based on a polyphasic approach involving molecular and biochemical evaluation. A total of 69 strains were isolated based on colony morphology and identified as Aspergillus oryzae/flavus based on internal transcribed spacer and calmodulin gene sequencing. Interestingly, none were toxigenic based on PCR amplification of intergenic regions of the aflatoxin cluster genes norB-cypA and the absence of aflatoxin in the culture supernatants by thin-layer chromatography analysis. Saccharification capability of the isolates, assessed through ${\alpha}-amylase$ and glucoamylase activities, revealed that two isolates, TNA24 and TNA15, showed the highest levels of activity. Although the degrees of variation in ${\alpha}-amylase$ and glucoamylase activities among the isolates were higher, there were only slight differences in acid protease activity among the isolates with two, TNA28 and TNA36, showing the highest activities. Furthermore, statistical analyses showed that ${\alpha}-amylase$ activity was positively correlated with glucoamylase activity (p < 0.001), and therefore screening for either was sufficient to predict the saccharifying capacity of the Aspergillus strain.

• Korean Journal of Veterinary Service
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• v.29 no.3
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• pp.277-285
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• 2006

Plasmids are covalently closed circular molecules of DNA that are stably inherited and replicate somewhat independently of the bacterial chromosome. Genes carried on plasmids can mediate a wide variety of important functions, including antibiotics (R plasmids) and heavy metals resistance, toxins production, cell penetration, iron chelation, complement resistance, and metabolic characteristics such as sucrose and lactose fermentation. Fifty strains of lactobacilli were isolated from 26 staters and 29 fermented milk products. They were classified 27 strains as Lactobacillus paracasei subsp paracasei, 11 stains as Lactococcus lactis subsp cremoris, 6 strains as L delbrueckii subsp lactis, 4 strains as L acidophius, and 2 strains as L delbrueckii subsp bulgaricus. All of these strains were examined for drug resistance and transferability of R plasmids. All of the isolates were sensitive to Am, C, CF, E, NB, P, T, and Te. But resistant to SXT 94% (47 strains), K 66% (33 strains), S 56% (28 strains), ENR 50% (25 strains), NOR 38% (19 strains) CIP 38% (19 strains), GM 16% (8 strains), and N 14% (7 strains), in order. And 32 different resistant patterns were found. The most frequently encountered patterns were CIP-ENR-K-NOR-S-SXT (5 strains). In vitro R plasmids transfer experiment, 57 antibiotic resistant strains which were not transfer to the recipient 2 Escherichia coli strains by conjugation, These results indicate that Lactobacillus in internal trade market' stater recognize R factor but transmissible R plasmid is not existed.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.252-259
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• 2009

We previously isolated Bacillus strains with high fibrinolytic activities (FAs) from cheonggukjang prepared by traditional ways. To test their potential as starters for cheonggukjang, soybean was fermented for 72 hr at $37^{\circ}C$ with each isolate and a control lab strain: B. subtilis CH3-25 (BS3-25), B. amyloliquefaciens CH51 (BA51), B. amyloliquefaciens CH86-1 (BA86-1), and B. subtilis 168 (BS168, control, lab strain). Viable cell numbers of all cheonggukjang samples rapidly increased and reached about $10^9$ CFU/g after 6 hr. During 72 hr, the initial pH of 6.3 rapidly increased to 8.1$\sim$8.2 for cheonggukjang fermented with BS3-25 or BA86-1, and 7.3 for those with BA51 or BS168. FAs and protease activities (acid, neutral, and alkaline) rapidly increased in cheonggukjang fermented with BS3-25, BA51, or BA86-1 during the first 12 hr. On the other hand, those of cheonggukjang fermented with BS168 slightly increased during the first 36 hr. There were significant changes in acid and neutral protease activities in cheonggukjang fermented with BA51 or BA86-1 during the 24 hr. Rapid increases of $\beta$-glucosidase activity corresponded well with rapid increases of $\alpha$-amylase and $\alpha$-galactosidase activities in addition to increases in antioxidant activities and the TPCs (total phenolic contents). The highest increase in the TPCs was observed in cheonggukjang fermented with BA86-1 while the least was that fermented with BS168.

• Journal of IKEEE
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• v.22 no.2
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• pp.258-265
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• 2018

This paper proposes an algorithm for reducing the starting current when the single-phase induction motor starts and analyzes its operation. Generally, the single-phase induction motors require several starters to generate the starting torque due to their structural characteristics. In this paper, a capacitor-start / capacitor-run method of the single-phase induction motor is basically adopted. This conventional method is efficient and has a large starting torque, but it generates about 5 ~ 6 times of inrush current at startup. As a result, the freezer starting device and peripheral devices are damaged and life time may be reduced. To reduce the inrush current, the current control algorithm based on the virtual dq model is presented to control the starting current. In addition, it validates the proposed algorithm through experiments to smooth transit from start-up operation to the rated operating region.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.9
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• pp.1137-1140
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• 2014

Faulty electric motors onboard vessels with anomalies in windings or poor insulation are usually repaired at land based workshops and reinstalled in place by crew hands after receiving the repaired motors. Especially for 3 phase induction motors which need Y-${\delta}$ starters with 6 lead wires, it would happen that the polarities of stator windings cannot be well distinguished if the original tags of these wires are erased or not visible clearly, resulting in subsequent damage to the repaired motor due to extreme current flow when the power is given to the motor the stator windings of which are wrongly connected in the polarity. This study proposes an easy way to make correct connection in winding polarities without failures based on the electro-magnetically induced voltages on windings when a slight DC current is supplied to a winding coil by using an analog multi-tester. The proposed method is applied to actual motors and delves into the applicability for polarity discrimination through a few measurements onboard vessels.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7847-7852
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• 2015

Purpose: Research carried out with gynecologic cancer patients using CAM was reviewed to provide a source for discussing which CAM method is used for which purpose, patients' perceptions on the effects/side effects occurred during/after using CAM and their sources of information regarding CAM. Materials and Methods: This literature review was carried out for the period between January 2000 and March 2015 using Scopus, Dynamed, Med-Line, Science Dırect, Ulakbim, Research Starters, Ebscohost, Cinahl Complete, Academic Onefile, Directory of Open Access Journals, BMJ Online Journals (2007-2009), Ovid, Oxford Journal, Proquest Hospital Collection, Springer-Kluwer Link, Taylor & Francis, Up To Date, Web Of Science (Citation Index), Wiley Cochrane-Evidence Base, Wiley Online Library, and Pub-Med search databases with "complementary and alternative medicine, gynecologic cancer" as keywords. After searching through these results, a total of 12 full length papers in English were included. Results: CAM use in gynecologic cancer patients was discussed in 8 studies and CAM use in breast and gynecologic cancer patients in 4. It was determined that the frequency of CAM use varies between 40.3% and 94.7%. As the CAM method, herbal medicines, vitamins/minerals were used most frequently in 8 of the studies. When the reasons why gynecologic cancer patients use CAM are examined, it is determined that they generally use to strengthen the immune system, reduce the side effects of cancer treatment and for physical and psychological relaxation. In this review, most of the gynecologic cancer patients perceived use of CAM as beneficial. Conclusions: In order that the patients obtain adequate reliable information about CAM and avoid practices which may harm the efficiency of medical treatment, it is recommended that "Healthcare Professionals" develop a common language.

• Korean Journal of Food Science and Technology
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• v.52 no.1
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• pp.11-18
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• 2020

Bacteria of the genus Enterococcus are of importance in food fermentations as well as their use as probiotics in humans and livestock. However, they are also important nosocomial pathogens that cause infections. Some strains are resistant to multiple antibiotics and possess virulence factors. The role of Enterococcus species in disease has raised issues on their safety for use in foods or as probiotics. First, this review summarized the positive and negative traits of Enterococcus spp. to illustrate the controversial nature of this bacterial genus and discussed the current genomic approaches can eliminate pathogenic strains. Then, this review examined the current status of starter development for traditional food fermentations and the regulation on the approval of novel food microorganisms in Korea to point out problems in the regulation. Based on the conclusions from the studies on Enterococcus spp., we suggested the direction of safety assessment of novel food microorganisms in Korea.