• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.254-260
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• 2016

Doenjang samples were prepared by inoculation of multiple starters consisting of two Bacillus spp., one yeast, and one fungus. Doenjang A was fermented with Bacillus amyloliquefaciens EMD17, B. amyloliquefaciens MJ1-4, Pichia farinosa SY80, and Rhizopus oryzae. Doenjang B and C were fermented with the same yeast and fungus but different Bacillus strains; namely, B. amyloliquefaciens EMD17 and B. subtilis CH3-5 for doenjang B, and B. amyloliquefaciens MJ1-4 and B. subtilis CH3-5 for doenjang C. Doenjang D was fermented with microorganisms present in rice straw (control). The doenjang samples were spiked with B. cereus ATCC14579 at two different levels, 10⁴ CFU/g doenjang (I) and 10⁷ CFU/g doenjang (II). All eight doenjang samples were fermented for 70 days at 25℃. Growth of B. cereus was inhibited in doenjang A, B, and C, with the bacterial cell count after 70 days being less than the initial 10⁴ CFU/g added, whereas B. cereus was not inhibited in doenjang D. Doenjang B showed the strongest inhibitory activity against B. cereus, with a cell count of less than 10³ CFU/g after 42 days, even when B. cereus was initially added at 10⁷ CFU/g. Some properties of the doenjang samples, such as pH, TA, and amino-type nitrogen content, were similar to those of doenjang fermented with starters only. The results indicate that carefully selected starters can effectively prevent the growth of B. cereus during doenjang fermentation.

• Korea journal of population studies
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• v.24 no.2
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• pp.149-177
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• 2001

This is a study on age-crime curve in Korea. Three data was used in this study as following: First is the crime statistics as aggregated data. Second is the police record(N=3.541 offences) of the male ex-offenders(N=988) who have been released in eleven prisons in 1987 as individual data. Third is the self-reported group-interview data(N=10.198 offences) administered to the male prisoners(N=979) in ten correctional facilities including eight adult prisons, one juvenile prison and one juvenile training center as another individual data. Generally, the right-skewness of age-crime curve has been explained through the difference of crime rate between early starters and late starters. Moffitt explains that this is because of the higher participation rate of the juvenile period of adolescence-limited offenders, but Godttfredson and Hirschi explain that this is because of a similar distribution in the crime rate of both early starters and late starters. the analysis of this study shows that Godttfredson and Hirschi’s explanation on the generality of age-crime-curve distribution is correct, but this can be modified by various factors like a economic crisis. And the peak age of juvenile period is consistent with the Moffitt’s hypothesis that the peak age is contributed to the increase of crime rate of late starters, not with Godttfredson and Hirschi’s one.

• Korean Journal of Child Studies
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• v.26 no.5
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• pp.367-377
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• 2005

Semi-structured in-depth interview method were used to test psycho-social comparison among first time offenders and repeated offenders. Data were analyzed by t-test and chi-square. Differences between first time offenders and repeated offenders were that there were more male offenders than female offenders, and violent and theft offenders were more than sex offenders fraud and traffic offenders; early starters were more repeated offenders than late starters; there were some variables such as runway of home, parents' caring attitude, school drop out and maladjustment affecting in repeated offenses; developmental environment of repeated offenders were more negative than first time offenders. Therefore, intervention and prevention program development of good parenting and schooling and forensic counseling focused on optimal developmental environment is needed.

• Journal of Microbiology and Biotechnology
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• v.27 no.5
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• pp.869-877
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• 2017

Lactic acid bacteria (LAB) are used as fermentation starters in vegetable and dairy products and influence the pH and flavors of foods. For many centuries, LAB have been used to manufacture fermented foods; therefore, they are generally regarded as safe. LAB produce various substances, such as lactic acid, ${\beta}$-glucosidase, and ${\beta}$-galactosidase, making them useful as fermentation starters. Existing functional substances have been assessed as fermentation substrates for better component bioavailability or other functions. Representative materials that were bioconverted using LAB have been reported and include minor ginsenosides, ${\gamma}$-aminobutyric acid, equol, aglycones, bioactive isoflavones, genistein, and daidzein, among others. Fermentation mainly involves polyphenol and polysaccharide substrates and is conducted using bacterial strains such as Streptococcus thermophilus, Lactobacillus plantarum, and Bifidobacterium sp. In this review, we summarize recent studies of bioconversion using LAB and discuss future directions for this field.

• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1397-1404
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• 2014

A few starters have been developed and used for doenjang fermentation but often without safety evaluation. Filamentous fungi were isolated from industrial doenjang koji, and their potential for mycotoxin production was evaluated. Two fungi were isolated; one was more dominantly present (90%). Both greenish (SNU-G) and whitish (SNU-W) fungi showed 97% and 95% internal transcribed spacer sequence identities to Aspergillus oryzae/flavus, respectively. However, the SmaI digestion pattern of their genomic DNA suggested that both belong to A. oryzae. Moreover, both fungi had morphological characteristics similar to that of A. oryzae. SNU-G and SNU-W did not form sclerotia, which is a typical characteristic of A. oryzae. Therefore, both fungi were identified to be A. oryzae. In aflatoxin gene cluster analysis, both fungi had norB-cypA genes similar to that of A. oryzae. Consistent with this, aflatoxins were not detected in SNU-G and SNU-W using ammonia vapor, TLC, and HPLC analyses. Both fungi seemed to have a whole cyclopiazonic acid (CPA) gene cluster based on PCR of the maoA, dmaT, and pks-nrps genes, which are key genes for CPA biosynthesis. However, CPA was not detected in TLC and HPLC analyses. Therefore, both fungi seem to be safe to use as doenjang koji starters and may be suitable fungal candidates for further development of starters for traditional doenjang fermentation.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.509-516
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• 2007

Starters of lactic acid bacteria(LAB) were isolated from the commercial yoghurt products and the four isolates have been studied on their identification and some physiological characteristics. For the purpose of identification, microscopic examination, API test, and 16s rRNA gene sequencing were conducted. Isolate A from a yogurt product of local dairy company A was shown to be Gram-positive rod-shaped bacterium. All strains isolated were turned out to be as Lactobacillus paracasei by using a API 50 CHL kit. In contrast, isolate A was identified as a strain of Lactobacillus helveticus based on the 16S rRNA sequencing data, and L. casei ssp. casei for both B and D and L. paracasei for C. All the isolates survived the simulated gastric juice, pH 2.0 within 3 hours and sharply decreased in viability so that no viable cell was observed after 4.5 hours incubation. In addition, the four isolated strains were almost identical in antibiotic susceptibility to six different kinds of antibiotics including erythromycin ($15\;{\mu}g$), ampicillin ($10\;{\mu}g$), gentamycin ($10\;{\mu}g$), neomycin ($30\;{\mu}g$), but rather resistant to colistin ($10\;{\mu}g$) and streptomycin ($10\;{\mu}g$). It was noteworthy that four isolates were confirmed to produce antibacterial substance against foodborne pathogens of Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli 0157:H7 as test organisms based on the inhibitory zones on an MRS soft agar medium. At presence, the inhibitory factor is unknown so that further studies are required to ascertain the active factor responsible for the inhibitory activities.

• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.319-324
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• 2012

Production of liquid starters using wheat bran as a medium for Rhizopus oryzae N174 and the changes in their characteristics noted during storage were investigated in this study. The optimal culture conditions of the liquid starters were determined to be 5~15% (w/v) wheat bran and 48~72 hrs of incubation. The effects of liquid starters with different storage periods and temperatures (-18, 4, 10 and $25^{\circ}C$) on the quality of wheat nuruk were evaluated. According to the results of the pH, acidity, reducing sugar and enzyme activities, it was found that liquid starter using wheat bran preserved for one day, at any temperature, is the best method of storage for seed cultures for R. oryzae N174.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.880-888
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• 2016

Changes in quality characteristics of gochujang prepared with different ingredients (white rice, barley, sorghum and millet, bamboo salt) and meju starters were studied. The gochujang samples were fermented for 6 weeks at $40^{\circ}C$ and analyzed for changes in their physicochemical properties and sensory characteristics. Eight different gochujang samples were prepared: WR-SS-AB, WR-SS-ABL, WR-BS-AB, WR-BS-ABL, MG-SS-AB, MG-SS-ABL, MG-BS-AB, MG-BS-ABL (WR: white rice, MG: mixed grains, SS: solar salt, BS: bamboo salt, AB: Aspergillus oryzae/Bacillus subtilis starter meju, ABL: Aspergillus oryzae/Bacillus subtilis/Lactobacillus plantarum starter meju). There were significant differences between experimental groups in terms of moisture content, pH, acidity, and color value. All gochujang samples showed increased moisture contents and pH as well as increased acidity and amino-type nitrogen during fermentation. MG-BS-ABL showed the highest contents of amino-type nitrogen and free amino acids after 6 weeks of fermentation compared with other experiment groups. In addition, MG-BS-ABL showed the highest sensory analysis score, including appearance, flavor, taste, and overall acceptability after the fermentation of samples. Based on the results, MG-BS-ABL exhibited similar quality characteristics as general gochujang but showed the highest sensory scores and contents of amino-type nitrogen and free amino acids. These results might be due to the high protein contents of mixed grains and high mineral contents of bamboo salt and fermented products from mixed probiotic starters.

• Food Science and Preservation
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• v.24 no.8
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• pp.1188-1194
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• 2017

Gochujang, a traditional Korean food, is fermented by mixing red pepper powder, various grain, meju and salt. Changes in the kind of ingredients and fermentation method could increase health functionalities. In this study, in vivo anti-colitis effects of gochujang prepared with mixed grains, bamboo salt baked 3 times and meju starters on DSS-induced colitis in C57BL/6 mice were studied. We prepared gochujang prepared with mixed grains (MG), bamboo salt, and Aspergillus oryzae (A) and Baccillus subtilis (B) mixed starters (MG-AB) and gochujang prepared with MG, bamboo salt and A, B and Lactobacillus plantarum (L) mixed starters (MG-ABL). MG-AB and MG-ABL significantly increased body weight and colon length compared to the control (p<0.05). MG-ABL showed significantly decreased interleukin-6 (IL-6) expression in serum compared to the control and MG-AB group (p<0.05). MG-ABL also regulated mRNA and protein levels of pro-apoptotic Bcl-2-associated X protein (Bax) and anti-apoptotic B-cell lymphoma-2 (Bcl-2) in the mice colon tissue (p<0.05). Therefore, MG-ABL exhibited the increased anticolitis effects by inhibiting damage of colon tissue, probably by regulating a pro-inflammatory cytokine of IL-6 and regulated apoptosis related genes. These results indicated that gochujang changed with good ingredients and starters had colitis preventive effects and might be due to active compounds in mixed grain and bamboo salt, and produced by L during the fermentation of gochujang.

• 전기의세계
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• v.22 no.5
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• pp.33-38
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• 1973

3상 농형 유도전동기는 가장 경제적이고 편리한 동력원이다. 본 고에서는 유도전동기용 기동기에 대하여 여러가지 설계양식의 타당성과 장래의 개발가능성을 고찰한다. 기동기는 전동기를 기동시킬뿐만 아니라 정상상태하에서 정지시키는 장치이다. 또 기동기는 과부하에 의한 손상으로부터 전동기를 보호하고, 정전시의 우발적인 재기동을 방지한다. 기동기의 보호기능이 전기적으로는 중요하지만 이문제는 성가신 기동책무만큼 빈번히 발생하지는 않는다. 전동기용 기동기의 또하나의 기능은 회전방향의 전환 및 속도조정이다.