• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.154-163
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• 1989

This studies were designed to improve the productivity of L-lysine by protoplast fusion and immobilized system of fusants using strains of Brevibacterium flavum ATCC 21528, Brevibacterium lactofermentum ATCC 21086 and Corynebacterium glutamicum 820. Mutants were isolated with concentration method of $300{\mu}g/ml$ penicillin-G after treatment of $250{\mu}g/ml$ N-methyl-N-nitro-N-nitrosoguanidine. B. flavum $37-2(Hos^-,\;Kan^r,\;AEC^r)$, B. lactofermentum $6-2(Ile^-,\;Val^-,\;Str^r,\;AEC^r)$ and C. glutamicum 57-5$(Met^-,\;Thr^-,\;Rif^r,\;AEC^r)$ were isolated from mutants. Protoplasts were induced by being incubated with $500{\mu}g/ml$ lysozyme of lysis solution for 6 hr and the ratio of protoplast formation and regeneration were ranging from 97-99% and 33-37%, respectively. Fusion frequencies of fusants of BBFL 21, BCFG 37 and BCLG 59 were shown in the range from $1.25{\times}10^{-6}\;to\;5.83{\times}10^{-7}$ under the optimum conditions. The fusant BBFL 21 showed the highest productivity of $411.1\;ng/ml{\cdot}hr$ L-lysine in the lysine productivity broth at $30^{\circ}C$ for 72hr. In the immobilization systems, fusant BBFL 21 was employed in various polymer matrices such as sodium alginate, polyacrylamide, agar and ${\alpha}-carrageena$. The immobilization of sodium alginate showed the highest productivity of $413\;ng/ml{\cdot}hr$ L-lysine in the batch system. Continuous fermentation of immobilization system by using tube fermentor was produced the highest productivity $416.7\;ng/ml{\cdot}hr $ L-lysine under optimum condition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.10B
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• pp.946-961
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• 2008

This study aims to provide guidelines on future policy for restructuring the scheme of aid programs associated with If small and medium-sized enterprises (i.e. SME) in Korea. For this purpose, we investigate an empirical dataset of recent aid programs deployed by Ministry of Information and Communication (i.e. MIC) for the last four years First, it is examined that the programs are practiced in accordance with their own policy objective by comparing matching samples between two groups such as program beneficiary and non-beneficiary companies. Second, positioning transition of programs within a same category is visualized in terms of two business portfolio analysis matrices. Third, an affiliation network matrix of (he programs is newly developed and then we attempt to analyze the programs relationship by the application of multidimensional scaling method to the affiliation network matrix. The empirical dataset is composed of two different kinds of corporate datasets. One is a corporate dataset of 8,994 beneficiary companies that are aided by MIC during the year of '03-'06. The other is also a corporate dataset of 18,354 non-beneficiary companies that have no records of the program supports during the years at all. Particularly, the matching samples of non-beneficiary companies are prepared in order to have comparable corporate age years (i.e. CAY) against beneficiary companies' CAY. Results show that; 1) up-to-date, the programs are properly assigned to IT SME conforming to their own policy objective; 2) however, as the year goes on, the following two distinct positioning transitions are revealed such as (1) both CAY and corporate sales (i.e. SAL) are increased simultaneously, (2) ratio of intangible assets (i.e. RIA) is decreased and ratio of operating gain to revenue (i.e. ROR) is increased. Hence, the role of the programs gets weakened with regard to providing seed money to technology innovation-typed IT SME so that a managerial adjustment of the programs is required consequently; 3) even though the model adequacy is not satisfactory through the analysis of multidimensional scaling method, the relationship of indirect-typed programs can relatively be stronger than that of direct-typed programs.

• Korean Journal of Environmental Agriculture
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• v.26 no.3
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• pp.246-253
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• 2007

This study was performed to enhance the cleanup efficiency of methoxyfenozide and bentazone by pH adjustment in the course of liquid-liquid partition and to develop an optimum analytical conditions using HPLC coupled with DAD for two matrices, brown rice and rice straw. Preparation procedure of brown rice sample was "extraction${\rightarrow}$coagulation${\rightarrow}$liquid-liquid partition$\rightarrow$-florisil C.C", and this procedure was samely applied to two compounds. In rice straw, preparation procedure of methoxyfenozide sample was "extraction$\rightarrow$-alkalization$\rightarrow$liquid-liquid extraction$\rightarrow$coagulation$\rightarrow$florisil C.C", and in the case of bentazone, "extraction$\rightarrow$alkalization$\rightarrow$liquid-liquid partition$\rightarrow$acidification$\rightarrow$liquid-liquid extraction$\rightarrow$florisil C.C". All these purified samples were redissolved in the mobile phases, acetonitile : 20 mM sodium acetate (75:25, v/v) for methoxyfenozide and acetonitrile : 75 mM sodium acetate, pH 6.0 (40:60, v/v) for bentazone. Recoveries of methoxyfenozide analysis in brown rice and rice straw were 83.5-97.4 and 86.4-97.3%, and detection limits were 0.02 and 0.04 mg/kg, respectively. Recoveries of bentazone in brown rice and rice straw were 86.8-101.9 and 88.3-94.5% and detection limits were 0.005 and 0.01 mg/kg, respectively. This methods seem to be usefully applied to the residue analysis of two compounds in the view of producing stable analytical condition and fair reproducibility.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.556-566
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• 2010

A new kinetic spectrophotometric method is developed for the measurement of Mn(II) in natural water samples. The method is based on the catalytic effect of Mn(II) with the oxidation of Gallocyanin by $KIO_4$ using nitrilotriacetic acid (NTA) as an activation reagent at 620 nm. The optimum conditions obtained are $4.00{\times}1^{-5}\;M$ Gallocyanin, $KIO_4$, $1.00{\times}10^{-4}\;M$ NTA, 0.1 M HAc/NaAc buffer of pH = 3.50, the reaction time of 5 min and the temperature of $30^{\circ}C$. Under the optimum conditions, the proposed method allows the measurement of Mn(II) in a range of $0.1\;-\;4.0\;ng\;mL^{-1}$ and with a detection limit of down to $0.025\;ng\;mL^{-1}$. The recovery efficiency in measuring the standard Mn(II) solution is in a range of 98.5 - 102%, and the RSD is in a range of 0.76 - 1.25%. The newly developed kinetic method has been successfully applied to the measurement of Mn(II) in both some environmental water samples and certified standard reference river water sample, JAC-0031 with satisfying results. Moreover, few cations and anions interfere with the measurement of Mn(II). Compared with the other catalytic-kinetic methods and instrumental methods, the proposed kinetic method shows fairly good selectivity and sensitivity, low cost, cheapness, low detection limit and rapidity. It can easily and successfully be applied to the real water samples with relatively low salt content and complex matrices such as bottled drinking water, cold and hot spring waters, lake water, river water samples.

• Tuberculosis and Respiratory Diseases
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• v.58 no.4
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• pp.367-374
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• 2005

Background : The fact that only 10-20% of chronic cigarette smokers develop chronic obstructive pulmonary disease (COPD) reflects the presence of genetic factors associated with the susceptibility to COPD. Recently, it was reported that the surfactant protein A increases the secretion of matrix metalloprotease 9, which degrades extracellular matrices of the lung, through a Toll-like receptor 2 (TLR2). In this context, possible role of TLR2 in the pathogenesis of COPD was postulated, and a functional dinucleotide repeat polymorphism in intron II of TLR2 was evaluated for any association with COPD. Method : Male patients with COPD and male smokers with a normal pulmonary function were enrolled in this study. The number of Guanine-Thymine repeats in intron II of the TLR2 gene were counted. Because the distributions of the repeats were trimodal, the alleles were classified into three subclasses, 12-16 repeats: short (S) alleles; 17-22 repeats: medium length (M) alleles; and 23-27 repeats: long (L) alleles. Result : 125 male patients with COPD and 144 age- and gender-matched blood donors with a normal lung function were enrolled. There were no differences in the distribution of each allele subclass (S, M and L) between the COPD and control group (p=0.75). The frequencies of the genotypes with and without each allele subclass in the COPD and control group were similar. Conclusion : A microsatellite polymorphism in intron II of TLR2 gene was not associated with the development of COPD in Koreans.

• Korean Journal of Environment and Ecology
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• v.33 no.2
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• pp.187-201
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• 2019

This study examined the physicochemical water quality and evaluated the ecological health in 14 sites of Geum River (upstream, mid-stream, and downstream) using the fish community distribution and guilds and eight multi-variable matrices of FAI (Fish Assessment Index) during June 2008-May 2009. The analysis of the water quality variables showed no significant variation in the upstream and mid-stream but a sharp variation due to the accumulation of organic matter from the point where the treated water of Gap and Miho streams flew. The analysis of physicochemical water properties showed that BOD, COD, TN, TP, Cond, and Chl-a tended to increase while DO decreased to cause eutrophication and algae development from the downstream where Miho and Gap stream merged. The analysis of fish community showed that the species richness index and species diversity index increased in the mid-stream area but decreased in the downstream area, indicating the stable ecosystem in the upper stream and the relatively unstable ecosystem in the downstream. The analysis of the species distribution showed that the dominant species were Zacco platypus that accounted for 20.9% of all fish species and Zacco koreanus that accounted for 13.1%. The analysis of the fish tolerance and feeding guild characteristics showed that the sensitive species, the insectivore species, and the aquatic species were dominant in the mid-stream point. On the other hand, contaminants from the sewage water treatment plant of Miho stream had a profound effect in the downstream to show the dominance of tolerant species, omnivorous species, and lentic species. Therefore, it is necessary to improve water quality by reducing the load of urban pollutants and to pay attention to the conservation and restoration of aquatic ecosystems.

• Journal of Intelligence and Information Systems
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• v.25 no.3
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• pp.89-115
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• 2019

This study was conducted to present the stylistic differences between Arthur Conan Doyle and Agatha Christie, famous as writers of classical mystery novels, through data analysis, and further to present the analytical methodology of the study of style based on text mining. The reason why we chose mystery novels for our research is because the unique devices that exist in classical mystery novels have strong stylistic characteristics, and furthermore, by choosing Arthur Conan Doyle and Agatha Christie, who are also famous to the general reader, as subjects of analysis, so that people who are unfamiliar with the research can be familiar with them. The primary objective of this study is to identify how the differences exist within the text and to interpret the effects of these differences on the reader. Accordingly, in addition to events and characters, which are key elements of mystery novels, the writer's grammatical style of writing was defined in style and attempted to analyze it. Two series and four books were selected by each writer, and the text was divided into sentences to secure data. After measuring and granting the emotional score according to each sentence, the emotions of the page progress were visualized as a graph, and the trend of the event progress in the novel was identified under eight themes by applying Topic modeling according to the page. By organizing co-occurrence matrices and performing network analysis, we were able to visually see changes in relationships between people as events progressed. In addition, the entire sentence was divided into a grammatical system based on a total of six types of writing style to identify differences between writers and between works. This enabled us to identify not only the general grammatical writing style of the author, but also the inherent stylistic characteristics in their unconsciousness, and to interpret the effects of these characteristics on the reader. This series of research processes can help to understand the context of the entire text based on a defined understanding of the style, and furthermore, by integrating previously individually conducted stylistic studies. This prior understanding can also contribute to discovering and clarifying the existence of text in unstructured data, including online text. This could help enable more accurate recognition of emotions and delivery of commands on an interactive artificial intelligence platform that currently converts voice into natural language. In the face of increasing attempts to analyze online texts, including New Media, in many ways and discover social phenomena and managerial values, it is expected to contribute to more meaningful online text analysis and semantic interpretation through the links to these studies. However, the fact that the analysis data used in this study are two or four books by author can be considered as a limitation in that the data analysis was not attempted in sufficient quantities. The application of the writing characteristics applied to the Korean text even though it was an English text also could be limitation. The more diverse stylistic characteristics were limited to six, and the less likely interpretation was also considered as a limitation. In addition, it is also regrettable that the research was conducted by analyzing classical mystery novels rather than text that is commonly used today, and that various classical mystery novel writers were not compared. Subsequent research will attempt to increase the diversity of interpretations by taking into account a wider variety of grammatical systems and stylistic structures and will also be applied to the current frequently used online text analysis to assess the potential for interpretation. It is expected that this will enable the interpretation and definition of the specific structure of the style and that various usability can be considered.

• Journal of Life Science
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• v.29 no.11
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• pp.1208-1217
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• 2019

Saposhnikovia has been used as a traditional medicinal herb in Asia because of the reported anti-inflammatory, anti-allergic rhinitis, pro-whitening, anti-atopy, anti-allergy, and anti-dermatopathy effects of the phytochemical compounds it contains. In this study, we investigated the antioxidant effects of a Saposhnikovia extract after fermentation by Lactobacillus plantarum BHN-LAB 33. Saposhnikovia powder was inoculated with L. plantarum BHN-LAB 33 and fermented at $37^{\circ}C$ for 72 hr. After fermentation, the total polyphenol content of the Saposhnikovia extract increased by about 14%, and the total flavonoid content increased by about 9%. The superoxide dismutase-like activities, DPPH radical scavenging, ABTS radical scavenging, reducing power activity, and tyrosinase inhibition activity also increased after fermentation by approximately 70%, 80%, 45%, 39%, and 44%, respectively. The results confirmed that fermentation of a Saposhnikovia extract by L. plantarum BHN-LAB 33 is an effective way to increase the antioxidant effects of the extract. The bioconversion process investigated in this study may have the potential to produce phytochemical-enriched natural antioxidant agents with high added value from Saposhnikovia matrices. These results can also be applied to the development of improved foods and cosmetic materials.

• Journal of Food Hygiene and Safety
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• v.36 no.1
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• pp.24-33
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• 2021

For this study, we surveyed concentrations of 8 mycotoxins (aflatoxin B1, B2, G1, G2, ochratoxin A, fumonisin B1, B2 and zearalenone) in agricultural products used for food and medicine by liquid chromatography-tandem mass spectrometry and conducted a risk assessment. Samples were collected at the Yangnyeong Market in Seoul, Korea, between January and November 2019. Mycotoxins were extracted from these samples by adding 0.1% formic acid in 50% acetonitrile and cleaned up by using an ISOLUTE Myco cartridge. The method was validated by assessing its matrix effects, linearity, limit of detection (LOD), limit of quantification (LOQ), recovery and precision using four representative matrices. Matrix-matched standard calibration was used for quantification and the calibration curves of all analytes showed good linearity (r2>0.9999). LODs and LOQs were in the range of 0.02-0.11 ㎍/kg and 0.06-0.26 ㎍/kg, respectively. Sample recoveries were from 81.2 to 118.7% and relative standard deviations lower than 8.90%. The method developed in this study was applied to analyze a total of 187 samples, and aflatoxin B1 was detected at the range of 1.18-7.29 ㎍/kg (below the maximum allowable limit set by the Ministry of Food and Drug Safety, MFDS), whereas aflatoxin B2, G1 and G2 were not detected. Mycotoxins that are not regulated presently in Korea were also detected: fumonisin (0.84-14.25 ㎍/kg), ochratoxin A (0.76-17.42 ㎍/kg), and zearalenone (1.73-15.96 ㎍/kg). Risk assessment was evaluated by using estimated daily intake (EDI) and specific guideline values. These results indicate that the overall exposure level of Koreans to mycotoxins due to the intake of agricultural products used for food and medicine is unlikely to be a major risk factor for their health.

• Journal of Food Hygiene and Safety
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• v.38 no.5
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• pp.319-331
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• 2023

Aminoglycoside antibiotics, also known as aminoglycosides (AGs), are veterinary drugs effective against a wide range of gram-negative and gram-positive bacteria. Owing to their recent use in cultured meats, it has become essential to establish an analytical method for safety management. AGs are highly polar compounds, and ion-pair reagents (IPRs) are used to ensure component separation. Owing to the high possibility of potential mechanical problems resulting from IPR addition to the mobile phase, an analytical method in which IPRs are added directly to the vial was explored. In this study, methods for analyzing 10 AGs via liquid chromatography-tandem mass spectrometry (LC-MS/MS) with the addition of two IPRs were validated for selectivity, detection limit, quantitation limit, recovery, and precision. The detection limit was 0.0001-0.0038 mg/kg, the quantification limit was 0.004-0.011 mg/kg, and the linearity (R²) within the concentration range of 0.01-0.5 mg/kg was over 0.99. Recovery and precision (expressed as relative standard deviation) evaluated in the two matrices (beef and cell culture media) ranged from 70.7% to 120.6% and 0.2% to 24.7%, respectively. The validated AG analytical method was then applied to 15 meats prepared from chicken, beef, and pork, and 6 culture media and additives used in cultured meat. No AGs were detected in any of the 15 meats distributed in Korea; however, streptomycin and dihydrostreptomycin were detected at levels ranging from 695.85 to 1152.71 mg/kg and 6.35 to 11.11 mg/kg, respectively, in the culture media additives. The LC-MS/MS method coupled with direct addition of IPRs to the vial can provide useful basic data for AG analysis and safety evaluation of meats as well as culture media and additives for cultured meats.