• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.188.2-188.2
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• 2011

The use of renewable energy sources is becoming increasingly necessary to minimize the problems derived from the global warming impacts caused by the utilization of fossil fuels as well as their limited supply and reservoir. Also, localized heavy rain has occurred in many areas. As a result, suspended wood waste is being inflow into the dam and the problem of waste disposal has occurred. It is a unique renewable and alternative source for the production of energy. The experiment using wood waste (dry weight 25.0g) was conducted for extraction sugars such as xylose, lactose and glucose. For the sugar extraction from wood waste, hydrolysis experiment using wood waste was conducted by two steps. First step was reacted with 72% sulfuric acid (24.0N and 37.5 ml) for 1hr at $30^{\circ}C$ and second step was reacted at $105^{\circ}C$ for one hour after adding 2.45times of hot water. Extracted sugar was used in the experiment of sugar consumption to estimate feasibility of ethanol production using yeast(P. Stipitis and S cerevisiae). As a result, sugar extracted from wood waste was effective consumed by yeast(P. Stipitis and S cerevisiae). The consumption rate by yeast was S. cerevisiae was faster than that of P. stipitis. It can be confirmed that resource as ethanol production using wood waste was available.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.250-258
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• 1989

S. mutans known as a causative causative agent of dental caries was isolated from a carious lesion of Korean in the present study. The physiological, biochemical characteristics and polysaccharide pattern of these isolates were compated with those of four laboratory strains ; AHT(a), FA-1F(b), LM7(e), and OMZ65(g). One hundred strains of oral streptococci were isolated from dental caries sites of Korean (one male and one female). Among these, 3 strains were identified as S. mutans. These strains were able to grow on selective media MS, MST, MSP, MSP1, MSB, MSBT and were stained dark pink when sprayed with solutions of mannitol and TTC. So, these strains were called strain 108, 110, and 120, respectively. Strain 108, 110, and 120 were bacitracin resistnt. As these strains contained particularly hippurate hydrolysis enzyme, they were distinguished from laboratory strains. Apart from laboratory strains, the strain 108 was not capable of fermenting lactose, the strain 110 was not able to ferment sorbitol, inulin, melibiose, raffinose and the strain120 was incapable of fermenting inulin, raffinose. All fractions of extracellular and ecll bound polysaccharide of the strain108, 110, and 120 were consisted of more glucan than fructan. Aside from laboratory strains, the isolated strains were composed of more water-insoluble glucans related adherence on solid surface than water-soluble. According to these results, the strain108, 110, and 120 had native characteristecs of S. mutans, but they were different from laboratory strains in some characteristics. Therefore, each of them was given a name to S. mutans KHC108, KHC110, and KHC120, respcetively.

• Korean Journal of Veterinary Service
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• v.34 no.3
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• pp.201-208
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• 2011

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is a pathogen of a variety of infections in horse. We studied biochemical and molecular characteristics of S. zooepidemicus isolated from the genital tract of Thoroughbred mares in Korea. Seventy-nine isolates were identified as S. zooepidemicus by biochemical and PCR method from 374 horses. The biochemical characteristics of S. zooepidemicus isolates were positive reaction of lactose and sorbitol. However, S. zooepidemicus isoltes were negative reaction of inulin, mannitol, raffinose, trehalose, aesculin hydrolysis, growth in 6.5% NaCl and variable reaction of maltose. Epidemiological investigations of S. zooepidemicus isolates were performed by fragment analysis of SzP (S. zooepidemicus protective protein) gene, CNE (collagen binding protein) gene and ISR (16s rRNA intergenic spacer region) gene using ABI Prism $3,130{\times}1$ Genetic Analyzer System. All isolates were shown single amplification size of 906 bp in CNE gene, but SzP and ISR gene were shown variable patterns of fragment size. The characteristics of S. zooepidemicus investigated in this study will be very useful for the prevention of infection and the studies of epidemiologic characteristics of S. zooepidemicus, causing the severe economic losses due to reproductive failures.

• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.733-738
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• 2007

An extracellular exoinulinase($2,1-\beta-D$ fructan fructanohydrolase, EC 3.2.1.7), which catalyzes the hydrolysis of inulin into fructose and glucose, was purified 23.5-fold by ethanol precipitation, followed by Sephadex G-100 gel permeation from a cell-free extract of Kluyveromyces marxianus YS-1. The partially purified enzyme exhibited considerable activity between pH 5 to 6, with an optimum pH of 5.5, while it remained stable(100%) for 3 h at the optimum temperature of $50^{\circ}C$. $Mn^{2+}\;and\;Ca^{2+}$ produced a 2A-fold and 1.2-fold enhancement in enzyme activity, whereas $Hg^{2+}\;and\;Ag^{2+}$ completely inhibited the inulinase. A preparation of the partially purified enzyme effectively hydrolyzed inulin, sucrose, and raffinose, yet no activity was found with starch, lactose, and maltose. The enzyme preparation was then successfully used to hydrolyze pure inulin and raw inulin from Asparagus racemosus for the preparation of a high-fructose syrup. In a batch system, the exoinulinase hydrolyzed 84.8% of the pure inulin and 86.7% of the raw Asparagus racemosus inulin, where fructose represented 43.6mg/ml and 41.3mg/ml, respectively.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1291-1298
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• 2015

Five different polymer nanofibers, namely, polyaniline nanofiber (PANI), magnetically separable polyaniline nanofiber (PAMP), magnetically separable DEAE cellulose fiber (DEAE), magnetically separable CM cellulose fiber (CM), and polystyrene nanofiber (PSNF), have been used for the immobilization of lactase (E.C. 3.2.1.23). Except for CM and PSNF, three polymers showed great properties. The catalytic activities (k_cat) of the free, PANI, PAMP, and magnetic DEAE-cellulose were determined to be 4.0, 2.05, 0.59, and 0.042 mM/min·mg protein, respectively. The lactase immobilized on DEAE, PANI, and PAMP showed improved stability and recyclability. PANI- and PAMP-lactase showed only a 0-3% decrease in activity after 3 months of vigorous shaking conditions (200 rpm) and at room temperature (25℃). PANI-, PAMP-, and DEAE-lactase showed a high percentage of conversion (100%, 47%, and 12%) after a 1 h lactose hydrolysis reaction. The residual activities of PANI-, PAMP-, and DEAE-lactase after 10 times of recycling were 98%, 96%, and 97%, respectively.

• Korean Journal of Veterinary Research
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• v.35 no.3
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• pp.497-504
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• 1995

Isolation of Staphylococcus hyicus subsp. hyicus from the skin of healthy chickens was performed and biochemical characteristics of the isolates were examined. Staphylococcus hyicus subsp hyicus was isolated from 129(14.8%) of 874 healthy chickens. The rate of isolation of this organism from chickens was found to vary depending upon the poultry farms at the isolation rate of 0% to 38.7% and this organism was isolated more frequently from adult chickens of over 1 year old than young chickens. All of the isolates were negative for haemolysis on rabbit, sheep, pig and chicken blood agars, protein A and ${\beta}$-glucuronidase, but positive for coagulase using pig plasma, heat-stable DNase, phosphatase and Tween 80 hydrolysis. Hyaluronidase was positive in 97.7% of isolates, but their reaction was weaker than that of swine strains of Staphylococcus hyicus subsp hyicus. The isolates were biotyped on the basis of the reactions for protease, urease, nitrate, galactose, trehalose and lactose, and 11 biotypes were found among the 129 isolates of Staphylococcus hyicus subsp hyicus.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.97-105
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• 1977

1) In order to obtain a microbial strain having a strong yeast cell wall lytic activity, about 156 isolates capable of forming clear zones on baker's yeast-peptone-bouillon agar plate were obtained from soil, mud and water samples and a strain K-42 with the highest lytic activity was identified as Bacillus circulans. 2) Effect of carbon sources on the lytic enzyme production by the K-42 strain was in the decreasing order of maltose>glucan>xylose>control in 2-day culture and of lactose>galactose>glucan>control in 3-day culture. Effect of inorganic nitrogen sources was in the decreasing order of ammonium acetate>sodium nitrate>control in 2-day culture and of ammonium chloride>ammonium oxalate>control in 3-day culture, whereas organic nitrogen sources except milk casein showed an increase in 2-day culture and a decrease in 3-day culture. Synergistic effect of carbon sources and nitrogen sources was not observed. 3) The enzyme production by the K-42 strain was greatly affected by pH change of the culture medium, thus a high lytic activity could be maintained by keeping the pH range of $7{\sim}8$ and adding carbon or nitrogen sources. 4) Optimum conditions for the lytic activity of the K-42 strain were obtained at $pH\;7{\sim}8$ and $60^{\circ}C$ and the extent of hydrolysis toward heated yeast cell wall was 65%.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.277-283
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• 2003

A bacterium producing the extracellular mannanase was isolated from Korean soybean paste. The isolate WL-7 has been identified as Bacillus subtiis on the basis on its 16S rRNA sequence, fatty acid composition, morphology and biochemical properties. The mannanase of culture supernatant was the most active around $55^{\circ}C$ and pH $6.0^{\circ}C$, and retained 90% of its maximum activity at range of pH 5.0∼7.5 and $50∼60^{\circ}C$. The additional carbohydrates including lactose, $\alpha$-cellulose, avicel, locust bean gum (LBG), wheat bran and konjak increased dramatically the mannanase productivity of strain WL-7. Especially, the maximum mannanase productivity was reached to 224 U/ml in LB medium supplemented with both 0.5% LBG and 0.5% konjak, which was approximately 200-folds more than that in LB medium. It was suggested that the increase of mannanase production was owing to induction of mannanase biosynthesis by both LBG and konjak hydrolysates transported following initial hydrolysis by extracellular mannanase during the cell growth.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.4
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• pp.32-39
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• 1986

A strain of Aspergillus niger CAD 1 which produces considerable amount of beta-galactosidase was selected from extracellular beta-galctaosidase producing fungi isolated from soil. Optimal conditions for the enzyme from Aspergillus niger CAD 1 were the growth in wheat bran supplemented with 0.5% skim milk powder at $30^{\circ}C$ for 72 hrs. The crude enzyme was purified 1,387 fold through DEAE-cellulosc and Sephadex G-100 chromatographr and its recovery was 6.2%, The optimal pH and temperature for the purified enzyme were pH 4.5 ana $45^{\circ}C$, respectively. The Km and Vmax on ONPG were $3.57{\times}10^3M$ and 33.0 unit/mg protein, whereas those on lacose were $83.3{\times}10^3M$and 15.33 unit/mg protein, respectively, The activation energy for the enzyme was 9,900 cal/mol and the enzyme had no metal ion requirement for its activity and stability. The hydrolysis of lactose in skim milk, 4.8% lactose solution and acidic whey were 65%, 70% and 78% after 10 hrs incubation at $45^{\circ}C$, when 182 units of the enzyme were used 50ml of the substrate solutions.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.189-195
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• 1999

Isoflavones of soy milk were mainly present as sugar conjugates such as genistin and daidzin which a glucosyl residue was attached to their aglycones, genistein and daidzein through ${\beta}-glycosidic$ bond, respectively. When soy milk containing sucrose as a sugar source was fermented with lactic acid bacteria, small amount of lactic acid $(0.16{\sim}0.29%)$ was produced but isoflavone conjugates were fully hydrolyzed. Supplementation of glucose or lactose was required for normal lactic acid production and affected the hydrolysis of isoflavone conjugates in some lactic acid bacteria. In the case of Lactobacillus delbrueckii subsp. delbrueckii KCTC 1047, glycosidic bond of isoflavone was fully hydrolyzed regardless of glucose supplementation. But only $25{\sim}40%$ of daidzin and $65{\sim}80%$ of genistin was hydrolyzed when glucose was added into soy milk in the other lactic acid bacteria, Lactobacillus bulgaricus KCTC 3188, Lactobacillus casei KCTC 3109, Lactobacillus delbrueckii subsp lactis KCTC 1058, Lactobacillus lactis KCTC 2181. The hydrolyzing enzyme, ${\beta}-glucosidase$ produced by lactic acid bacteria except Lactobacillus delbrueckii subsp. delbrueckii KCTC 1047 could be considered as inducible in the fermentation of soy milk and its production was decreased when glucose was added.