• Journal of Microbiology and Biotechnology
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• v.21 no.3
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• pp.267-273
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• 2011

Methyl violet, used extensively in the commercial textile industry and as a biological stain, is a hazardous recalcitrant. Aspergillus sp. strain CB-TKL-1 isolated from a water sample from Tsumoriri Lake, Karzok, Ladakh, India, was found to completely decolorize methyl violet within 24 h when cultured under aerobic conditions at $25^{\circ}C$. The rate of decolorization was determined by monitoring the decrease in the absorbance maxima of the dye by UV-visible spectroscopy. The decolorization of methyl violet was optimal at pH 5.5 and $30^{\circ}C$ when agitated at 200 rpm. Addition of glucose or arabinose (2%) as a carbon source and sodium nitrate or soyapeptone (0.2%) as a nitrogen source enhanced the decolorization ability of the culture. Furthermore, the culture exhibited a maximum decolorization rate of methyl violet after 24 h when the C:N ratio was 10. Nine N-demethylated decolorized products of methyl violet were identified based on UV-visible spectroscopy, Fourier transform infrared (FTIR), and LC-MS analyses. The decolorization of methyl violet at the end of 24 h generated mono-, di-, tri-, tetra-, penta-, and hexa-N-demethylated intermediates of pararosaniline. The variation of the relative absorption peaks in the decolorized sample indicated a linear decrease of hexa-N-demethylated compounds to non-N-demethylated pararosaniline, indicating a stepwise N-demethylation in the decolorization process.

• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1559-1565
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• 2014

Cellulase and xylanase are main hydrolysis enzymes for the degradation of cellulosic and hemicellulosic biomass, respectively. In this study, our aim was to develop and test the efficacy of a rapid, high-throughput method to screen hydrolytic-enzyme-producing microbes. To accomplish this, we modified the 3,5-dinitrosalicylic acid (DNS) method for microwell plate-based screening. Targeted microbial samples were initially cultured on agar plates with both cellulose and xylan as substrates. Then, isolated colonies were subcultured in broth media containing yeast extract and either cellulose or xylan. The supernatants of the culture broth were tested with our modified DNS screening method in a 96-microwell plate, with a $200{\mu}l$ total reaction volume. In addition, the stability and reliability of glucose and xylose standards, which were used to determine the enzymatic activity, were studied at $100^{\circ}C$ for different time intervals in a dry oven. It was concluded that the minimum incubation time required for stable color development of the standard solution is 20 min. With this technique, we successfully screened 21 and 31 cellulase- and xylanase-producing strains, respectively, in a single experimental trial. Among the identified strains, 19 showed both cellulose and xylan hydrolyzing activities. These microbes can be applied to bioethanol production from cellulosic and hemicellulosic biomass.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.1004-1014
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• 2013

Six nonpathogenic fungal strains isolated from alkaline soils of Buenos Aires Province, Argentina (Acremonium murorum, Aspergillus sidowii, Cladosporium cladosporoides, Neurospora tetrasperma, Purpureocillium lilacinum (formerly Paecilomyces lilacinus), and Westerdikella dispersa) were tested for their ability to produce keratinolytic enzymes. Strains were grown on feather meal agar as well as in solid-state and submerged cultures, using a basal mineral medium and "hair waste" as sole sources of carbon and nitrogen. All the tested fungi grew on feather meal agar, but only three of them were capable of hydrolyzing keratin, producing clear zones. Among these strains, P. lilacinum produced the highest proteolytic and keratinolytic activities, both in solid-state and submerged fermentations. The medium composition and culture conditions for the keratinases production by P. lilacinum were optimized. Addition of glucose (5 g/l) and yeast extract (2.23 g/l) to the basal hair medium increased keratinases production. The optimum temperature and initial pH for the enzyme production were $28^{\circ}C$ and 6.0, respectively. A beneficial effect was observed when the original concentration of four metal ions, present in the basal mineral medium, was reduced up to 1:10. The maximum yield of the enzyme was 15.96 $U_c/ml$ in the optimal hair medium; this value was about 6.5-fold higher than the yield in the basal hair medium. These results suggest that keratinases from P. lilacinum can be useful for biotechnological purposes such as biodegradation (or bioconversion) of hair waste, leading to a reduction of the environmental pollution caused by leather technology with the concomitant production of proteolytic enzymes and protein hydrolyzates.

• Journal of Microbiology and Biotechnology
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• v.27 no.7
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• pp.1345-1358
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• 2017

The impact of overproduction of a heterologous protein on the metabolic system of host Lactococcus lactis was investigated. The protein expression profiles of L. lactis IL1403 containing two near-identical plasmids that expressed high- and low-level of the green fluorescent protein (GFP) were examined via shotgun proteomics. Analysis of the two strains via high-throughput LC-MS/MS proteomics identified the expression of 294 proteins. The relative amount of each protein in the proteome of both strains was determined by label-free quantification using the spectral counting method. Although expression level of most proteins were similar, several significant alterations in metabolic network were identified in the high GFP-producing strain. These changes include alterations in the pyruvate fermentation pathway, oxidative pentose phosphate pathway, and de novo synthesis pathway for pyrimidine RNA. Expression of enzymes for the synthesis of dTDP-rhamnose and N-acetylglucosamine from glucose was suppressed in the high GFP strain. In addition, enzymes involved in the amino acid synthesis or interconversion pathway were downregulated. The most noticeable changes in the high GFP-producing strain were a 3.4-fold increase in the expression of stress response and chaperone proteins and increase of caseinolytic peptidase family proteins. Characterization of these host expression changes witnessed during overexpression of GFP was might suggested the metabolic requirements and networks that may limit protein expression, and will aid in the future development of lactococcal hosts to produce more heterologous protein.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.653-657
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• 2011

The efficiency of clove oil, MS-222, and 2-phenoxyethanol was evaluated as anesthetics in juvenile Scomber japonicus. Stage A5 of anesthesia was assumed to be sufficient for conducting routine aquaculture procedures in less than 3 min, with recovery (stage R5) in less than 5 min. The lowest effective doses of the three anesthetics were 50 mg $L^{-1}$ clove oil (anesthetic time of 71.3 s and recovery time of 167.0 s), 100 mg $L^{-1}$ MS-222 (anesthetic time of 70.7 s and recovery time of 115.7 s), and 400 mg $L^{-1}$ 2-phenoxyethanol (anesthetic time of 86.7 s and recovery time of 95.0 s). Anesthetic times decreased with increasing doses for all three anesthetic agents, and fish anesthetized with clove oil exhibited the longest recovery times. After 30 min, the highest plasma cortisol and lactate levels were detected with the use of clove oil, whereas the lowest values were observed with 2-phenoxyethanol. In addition, high glucose levels were maintained during recovery with clove oil, but the treatments did not significantly differ. The most effective of the three anesthetic agents was 2-phenoxyethanol, although all were considered acceptable for use in cultures of juvenile Scomber japonicus.

• Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.47-57
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• 2014

Thai Jasmine rice (Oryza sativa, long grain Indica var.) is popular in southeastern Asia and China due to its non-glutinous, fluffy texture and fragrant smell. However it has a high starch digestibility, which leads to an increased glycemic index (GI). Therefore it may require modified cooking methods for diabetes patients. The objectives of this study were to optimize the ratio of Thai Jasmine rice, sea tangle, and olive oil (CLTR) based on consumers' acceptance. The GI of plain cooked Thai Jasmine rice (CLR) was measured as a control. Sensory evaluation and response surface methodology were used to determine the optimal ratio. Texture analysis and nutritional evaluation were also performed on the optimal recipe of cooked Jasmine rice with sea tangle. A multiple regression equation was developed in quadratic canonical polynomial models. We used 26 trained Chinese panelists in their forties to rate color, flavor, adhesiveness, and glossiness, which we determined were highly correlated with overall acceptability. The optimal CLTR formula was 34.8% rice, 2.8% sea tangle, 61.9% water, and 0.5% olive oil. Compared to CLR, CLTR had a lower hardness, but a higher springiness and cohesiveness. However, CLR and CLTR had the same adhesiveness and chewiness. The addition of sea tangle and olive oil delayed retro-gradation of starch in CLTR and increased total dietary fiber, and protein and ash contents. The degree of gelatinization, and in vitro protein and starch digestibility of CLTR were lower than those of CLR. Based on Wolver' method, the GI of CLTR (52.9, incremental area under the glycemic-response curve, ignoring the area below fasting, as used for calculating the GI [Inc]) was lower compared with that of CLR (70.94, Inc), which indicates that CLTR is effective in decreasing and stabilizing blood glucose level, owing to its lower degree of gelatinization and starch digestibility. Our results show that CLTR can contribute to the development of a healthier meal for families and the fast food industry.

• Korean Journal of Food Science and Technology
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• v.4 no.3
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• pp.194-199
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• 1972

To investigate the feasibility of producing yoguhrt from soybean milk which will be acceptable for Korean this experiment was carried out. The addition of pasteurized milk into soybean milk speeded up acid production by L. casei and also demonstrated the improvement of acceptability of the product. Certain additives like glucose, lactose and yeast extract also stimulated acid production. It was found that the yoguhrt of pH range of $4.2{\sim}3.7$ was well agreed to Korean preference. It was also observed by panel test in this study that the acceptability of Korean for yoguhrt increased through repeated tasting, and in consequence, this would turn out to be an ordinary acceptable food item, even though it is felt quite objectionable at the beginning of taste.

• Korean journal of food and cookery science
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• v.32 no.2
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• pp.188-196
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• 2016

Purpose: In order to develop soy sauce and increase its functionality, by adding black garlic extract. Methods: We compared quality characteristics and antioxidant activity of 20 days aging black garlic soy sauce from mixed manufacturers with raw soy sauce (commercial fermented soy sauce) and different ratio of black garlic extract (65 Brix, 0.3-5.0%). Results: The salt content of the black garlic extract (0.3-5.0%) added soy sauce were 12.35-12.77%. The pH was lowered to 4.99, and acidity was increased to 2.12%, depending on the increase in black garlic extract added ratio. The crude protein and total nitrogen contents were 6.23-6.62% and 1.10-1.16%, respectively, and content of amino form nitrogen was 0.52-0.53%, without significant differences between experimental groups. Contents of reducing sugar and free sugars (fructose and glucose) tended to be higher with higher mixing ratios of black garlic extract. Total phenolic compounds and flavonoids contents were significantly increased in the 3% and 5% black garlic extract addition group. At concentrations of 62.5, 125, 250, 500, 1,000 and $2,000{\mu}g/mL$, the DPPH and ABTS radical scavenging activity of the polysaccharides isolated from control soy sauce and 5% black garlic extract added soy sauce showed higher correlation with their concentration. Conclusion: These results, confirmed that the soy sauce produced by adding more than 3% of black garlic extract has high antioxidant activity.

• Journal of the Korean Society of Safety
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• v.24 no.6
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• pp.157-162
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• 2009

Radioactive medicines are used a lot owing to the increase of a PET-CT examination using glucose metabolism useful for the early diagnosis of diseases. Therefore, the spatial dose that is generated from patients and their surroundings causes the patients' guardians and health professional to be exposed to radiation. However, they get unnecessarily exposed to radiation because medical institutions lack in space for isolation and recognition of the examination. This research intended to examine the spatial dose rates by measuring the dose emitted from the patient for 48 hours to whom F-18 FDG was administered. The spatial dose rates that were measured 100cm away from the patient's body after F-18 FDG was injected were $65.88{\mu}$Sv/hr at 60-minute point, $45.13{\mu}$Sv/hr at 90-minute point, $9.88{\mu}$Sv/hr at 6-hour point, and $1.24{\mu}$Sv/hr at 12-hour point. When the dose that the guardian and health professional got was converted into the annual(240-day working) accumulative dose, it was examined that the guardian received 81.56 mSv/yr and health professional received 49.36mSv/yr. In addition, the result has revealed that the dose that the patient received from one time of PET-CT examination was 3.75mSv/yr, which is 1.5 times more when compared with the annual natural radiation exposure dose.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.134-137
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• 2016

Big data analysis refers the ability to store, manage and analyze collected data from an existing database management tool. In addition, extract value from large amounts of structured or unstructured data set and means the technology to analyze the results. Meta-analysis is a statistical integration method that delivers an opportunity to overview the entire result of integrating and analyzing many quantitative research results. Meta-analysis is sometimes expressed as an analysis of another analysis. Commonly, factors of metabolic syndrome can be defined as abdominal obesity, high triglycerides, low high density lipoprotein cholesterol, elevated blood pressure, and elevated fasting glucose. This study will find meaningful mediator variables for criterion variables that affect before and after the metabolic syndrome studies, on the basis of the results of a meta-analysis. We reviewed a total of 5 studies related to metabolic syndrome published in Korea between 2000 and 2016, where a cause and effect relationship is established between variables that are specified in the conceptual model of this study.