• Journal of Life Science
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• v.9 no.2
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• pp.160-168
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• 1999

Butyrate is one of the short-chain fatty acids that are present in the colon of mammals in millimolar concentration as a result of microbial anaerobic fermentation of dietary fiber, undigested starch, and proteins. In this study, sodium butyrate was examined in HT29 cell, human colonic cancer cell line, on cell viability, alkaline phosphatase activity, PLC-${\gamma}$1 expression and complex sphingolipid biosynthesis. Treatment with butyrate showed that the decrease of cell adhesion and viability was time-dependent. Sodium butyrate also induced to increase the activity of alkaline phosphatase which is a differentiation marker enzyme and decrease the expression of PLC-${\gamma}$1. Biosynthesis of sphingomyelin and galactosylceramide by butyrate treatment were decreased so fast but ceramide was increased 680dpm/mg protein% more than untreated group on first day and then decreased fast. In addition, acid ceramidase and neutral ceramidase activity were inhibited early stage by sodium butyrate. These results suggest that sodium butyrate causes cell differentiation or cell growth arrest of HT29 cell accompanied by early increase of ceramide content and alkaline phosphatase activity and decrease of galactosylceramide content and PLC-r1 expression.

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.449-455
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• 2005

To reduce saft content of kochujang, various combinations of sub-materials such as ethanol mustard and chitosan were added to kochujang, and their effects on microbial characteristics, enzyme activities, and physicochemical characteristics of kochujang were investigated after 12 weeks of fermentation. Activities of ${\beta}$-amylase and pretense were low in ethanol-mustard-chitosan-added kochujang, whereas no significant difference was observed in ${\alpha$-amylase activity among all groups. Number of viable yeast cells decreased remarkably in mustard-added kochujang during late aging period, and anaerobic bacterial counts decreased in sub-material-added groups. Consistency of kochujang increased by addition of sub-materials, and oxidation-reduction potential was low in chitosan-added group. Mustard-chitosan-added kochujang showed lowest increase in total color difference(${\Dalta}E$) and decrease in water activity. PH of kochujang wns highest in mustard-chitosan-added kochujang, resulting in significantly increased titratable acidity. Addition of sub-material increased reducing sugar contents of kochujang, whereas ethanol production was significantly repressed in mustard-chitosan-added kochujang. Amino nitrogen content was Highest in mustard-chitosan-added kochujang during late aging period, whereas ammonia nitrogen content was lower in ethanol-mustard-added kochujang. Results of sensory evaluation indicated ethanol-mustard-added kochujang was more acceptable than other groups in taste and overall acceptability.

• Journal of Pharmacopuncture
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• v.20 no.2
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• pp.127-131
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• 2017

Objectives: Polymorphonuclear neutrophils (PMNs) constitute the first line of defense against invading microbial pathogens. Early events in inflammation involve the recruitment of neutrophils to the site of injury or damage where changes in intracellular calcium can cause the activation of pro-inflammatory mediators from neutrophils including superoxide generation, degranulation and release of myeloperoxidase (MPO), productions of interleukin (IL)-8 and tumor necrosis factor ${\alpha}$ ($TNF-{\alpha}$), and adhesion to the vascular endothelium. To address the anti-inflammatory role of flavonoids, in the present study, we investigated the effects of the flavonoids quercetin and vitexin on the stimulus-induced nitric oxide (NO), $TNF-{\alpha}$, and MPO productions in human neutrophils. Methods: Human peripheral blood neutrophils were isolated, and their viabilities were determined by using the Trypan Blue exclusion test. The polymorphonuclear leukocyte (PMNL) preparations contained more than 98% neutrophils as determined by morphological examination with Giemsa staining. The viabilities of cultured neutrophils with various concentrations of quercetin and vitexin ($1-100{\mu}M$) were studied using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays. Neutrophils were cultured in complete Roswell Park Memorial Institute (RPMI) medium, pre-incubated with or without quercetin and vitexin ($25{\mu}M$) for 45 min, and stimulated with phorbol 12-myristate 13-acetate (PMA) ($10^{-7}M$). NO production was carried out through nitrite determination by using the Griess method. Also, the $TNF-{\alpha}$ and the MPO productions were measured using enzyme-linked immunosorbent assay (ELISA) kits and MPO assay kits. Results: Neutrophil viability was not affected up to a concentration of $100{\mu}M$ of quercetin or vitexin. Both quercetin and vitexin significantly inhibited $TNF-{\alpha}$, NO, and MPO productions in human neutrophils (P < 0.001). Conclusion:The present study showed that both quercetin and vitexin had significant anti-inflammatory effects. Thus, treatment with either quercetin or vitexin may be considered as a therapeutic strategy for treating patients with neutrophil-mediated inflammatory diseases.

• Journal of the Korean Wood Science and Technology
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• v.15 no.4
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• pp.18-25
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• 1987

The cellulolytic activities of Aspergillus fumigatus KC-1 was investigated, which showed the most active producer of cellulase among the 256 strains of cellulose-decomposing microorganisms screened in our laboratory. All the examined cellulolytic activities (filter paper-, Avicel-, cotton-, CMC-, salicin- and xylansaccharifying activity) in a culture of A. fumigatus KC-1 grown on 1% popular sawdust pretreated with peroxide alkaline reached a maximum within 4-5 days. The optimum pH and temperature for the enzymatic activity was found to be pH 4.5 and $60^{\circ}C$ respectively. The sawdust of poplar wood delignified with 1% NaOH and 20% peracetic acid succesively recorded the highest hydrolysis rate in the tests of enzymatic saccharification. The major end product of hydrolysis of poplar wood with the cellulolytic enzymes obtained from A. fumigatus KC-1 was glucose with small amount of cellobiose and xylose. It can be concluded from these results that A. fumigatus KC-1 is an advantagous source of a cellulase that is capable of hydrolyzing cellulose to glucose rapidly. The influence of degree of delignification, substrate size and its concentration on the rate of hydrolysis of poplar wood was also discussed.

• Microbiology and Biotechnology Letters
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• v.4 no.4
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• pp.145-151
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• 1976

Cultural characteristics of a strain of Streptomyces sp. K-14 (KFCC 35051) producing glucose isomerase were demonstrated. The glucose isomerase was produced when the strain was grown in the medium containing pure xylan or xylan.containing materials such as wheat bran or com cob. The optimum condition was attained in a culture medium composed of 3 % wheat bran or com cob, 2 % com steep liquor, 0.1% $MgSO_4$$7H_2O$ and 0.012 % $CoSO_4$$7H_2O$ for the production of the glucose isomera,e. The production of the enzyme reached to a maximum level when the strain was cultured for 40 hrs $30^{\circ}C$ and pH 7.0.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.1
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• pp.7-11
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• 1990

As the putrefaction of fish is greatly relied on the microorganisms inhabited in the viscera of them, we investigated the microfloral changes in the viscera of sardine, Sardinops melanosticta, which has been caught a lot in adjacent sea of Korea but showed rapid spoilage, after storages with various temperature. The following results were obtained. Viable cell counts at $25^{\circ}C$ of the viscera of sardine were $1.6\times10^5/g$ at the fresh sample, $1.5\times10^5/g$ at the frozen sample, $2.9\times10^8/g$ at the spoiled samples. The most predominant microbial genera from the fresh sardine were Moraxella spp.($31.4\%$) and Pseudomonas spp.($28.6\%$), but Enterobacteriaceae($83.1\%$) was in spoiled sample. While Moraxella spp.($46.2\%$) and Flavobacterium-Cytophaga($21.0\%$) were predominant in the frozen sample and Enterobacteriacear($69.6\%$) was in the thawed-spoiled sample. The rates of proteolytic enzyme producing bacteria were $20\%$ in the fresh sample, $22\%$ in the frozen sample but the rates were increased to $52\%,\;29\%$ in the spoiled sample and the thawed-spoiled sample respectively.

• Microbiology and Biotechnology Letters
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• v.28 no.3
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• pp.167-171
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• 2000

Analysis of Production of Thermostable Alkaline Protease using Thermoactinomyces sp. E79. Jung, Sang Won, Sung-Sik Park, Yong-Cheol Park" Tae Kwang Oh2, and Jin-Ho Seo*, Department of Food Science and Technology, Seoul National University, Suwon 441-744, Korea, 1lnterdisciplinary program [or Biochemical Engineering & Biotechnology, Seoul National Univer5it}~ Seoul 151 "7421 Koreal 2Microbial Enzyme RU, Korea Research Institute of Bioscience & Biotechnology, Po. Box 1151 Yusong, Taejon 305"6001 Korea - This research was undertaken to analyze fermentation properties of Thermoactinomyces sp. E79 for production of a thermostable alkaline protease, which is able to specifically hydrolyze defatted soybean meal (DSM) to amino acids. TIle optimum pH for cell growth and protease production was pH 6.7, Thermoactinomyces sp. E79 did not grow at pHlO Among carbon sources tested, soluble starch was the best for protease production, while glucose repressed protease production. Tryptone was found to be the best nitrogen source for cell growth and soytone was good tor protease production. Oxygen transfer rate played an important role in producing thermostable alkaline protease. Ma'<..imum values of 6.58 glL of dry cell weight and 43.0 UJmL of protease activity were obtained in a batch fermentation using a 2.5 L jar fermentor at 1.93 X 102 hr-l of volumetric oxygen transfer coeff'jcient (kLa). Addition of 200 mgIL humic acid to the growth medium resulted in 1.64 times higher protease activity and 1.77 times higher cell growth than the case without humic acid addition.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.216-223
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• 2003

A 1.3-kb of chitosanase gene (choA) encoding 45-kDa polypeptide was cloned, expressed, and characterized from a newly isolated Bacillus cereus H-1. The chitosanase protein (ChoA) of B. cereus H-l was purified to homogeneity by ammonium sulfate precipitation and CM-sephadex column chromatography. Optimum pH was around 7, and stable pH range in the incubation at 50 C was 4-11. Optimum temperature was around 50 C, and enzyme activity was relatively stable below 45 C. ChoA showed the activities toward carboxymethyl cellulose (CMC) in addition to soluble or glycol chitosan. Based on MALDI-TOF MS analysis of purified ChoA, the entire amino acid sequence of ChoA was interpreted by database searching of previously known Bacillus chitosanases. A 1.6 kb of PCR product of corresponding chitosanase gene was obtained and its DNA sequence was determined. The deduced amino acid of choA revealed that ChoA have a 98% homology with those of Bacillus sp. No.7-M strain and Bacillus sp. KCTC0377BP. The recombinant ChoA protein was expressed in E. coli DH5$\alpha$. Deduced amino acid comparison of choA with other chitosanases suggested that it belongs to family 8 microbial endo-chitosanase with chitosanase-cellulase activity.

• Journal of Microbiology and Biotechnology
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• v.21 no.8
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• pp.861-868
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• 2011

A xylanase gene, xyn7c, was cloned from Paenibacillus sp. 12-11, an alkalophilic strain isolated from the alkaline wastewater sludge of a paper mill, and expressed in Escherichia coli. The full-length gene consists of 1,296 bp and encodes a mature protein of 400 residues (excluding the putative signal peptide) that belongs to the glycoside hydrolase family 10. The optimal pH of the purified recombinant XYN7C was found to be 8.0, and the enzyme had good pH adaptability at 6.5-8.5 and stability over a broad pH range of 5.0-11.0. XYN7C exhibited maximum activity at $55^{\circ}C$ and was thermostable at $50^{\circ}C$ and below. Using wheat arabinoxylan as the substrate, XYN7C had a high specific activity of 1,886 U/mg, and the apparent $K_m$ and $V_{max}$ values were 1.18 mg/ml and 1,961 ${\mu}mol$/mg/min, respectively. XYN7C also had substrate specificity towards various xylans, and was highly resistant to neutral proteases. The main hydrolysis products of xylans were xylose and xylobiose. These properties make XYN7C a promising candidate to be used in biobleaching, baking, and cotton scouring processes.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.90-96
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• 2017

Gray mold disease, cause by Botrytis cinerea, occurs severe damage on varieties of fruit and vegetable production, and have no a critical control method. In case of chemicals control, it is a trigger emergence of drug resistance strains due to using them continuously. In addition, the pathogen is difficult to control naturally because it is possible to survive regardless of host status. In this study, microorganisms were isolated from tomato flower and hive samples and in order to select suitable microbial control agents for tomato gray mold disease. During six-months study, we isolated 1,004 isolates from flower and 925 isolates from pollinator hive samples. Among them, 6 strains were selected based on result of antifungal activity test. The selected strains showed not only strong antifungal activity against gray mold pathogen, but also cellulase and protease enzyme activities. The selected strains were identified as Paenibacillus polymyxa. In plant assay, P. polymyxa prevented the gray mold disease occurrence near 75%.