• Applied Biological Chemistry
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• v.51 no.1
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• pp.11-16
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• 2008

The extraction conditions for resveratrol production from grape fruit stem, which is a by-product of grape processing, were optimized to develop high-functional grape-based products. Additionally, the bioefficacy of grape fruit stem extract (GFSE) as an antioxidant agent was evaluated. Resveratrol was extracted using various experimental conditions such as extractant type, extractant concentration, raw material-extractant ratio, extraction time and temperature, and the results were analyzed using a statistical program (SPSS). The resveratrol yield was the highest when 80% ethanol with a raw-material-extractant ratio of 1:10 (w/v) was used. In addition, the optimal temperature and time were selected as $60^{\circ}C$ and 90 min, respectively. When the antioxidant activity was analyzed and expressed as DPPH radical scavenging activity and SOD-like activity, the antioxidant activity of GFSE was higher than that of BHT, BHA and L-ascorbic acid. Finally, it was found that GFSE could be used as a raw material for the production of high antioxidant agents.

• Korean Chemical Engineering Research
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• v.44 no.4
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• pp.363-368
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• 2006

This study selected the optimal catalyst for the process of producing $C_9$-alcohol by hydrogenating $C_9$-aldehyde, and carried out an experiment in order to establish the operating condition for maximizing the yield of $C_9$-alcohol. The BET surface area and the specific area of copper were most excellent in $CuO/ZnO/Al_2O_3$ (60:30:10 wt％) catalyst produced using acetate as a precursor of copper and $Na_2CO_3$ as a precipitant, and the catalyst also showed the highest performance in $C_9$-aldehyde hydrogenation. Using a trickle bed reactor loaded with optimized catalyst, we attained 94.1 wt％ yield of $C_9$-alcohol under the condition of $175^{\circ}C$, 800 psi and $WHSV=3hr^{-1}$. According to the result of comparing with other catalysts used in the hydrogenation of aldehyde, the catalyst showed similar performance to that of Ni/kieselghur and higher than that of $Cu-Ni-Cr-Na/Al_2O_3$ and $Ni-Mo/Al_2O_3$. According to the result of examining the stability of the catalyst through a long-term catalysis test, the yield of $C_9$-alcohol decreased slowly after around 72 hours due to the increasing production of high boiling-point byproducts.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.187-191
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• 1998

For efficient and economical production of Btrc,illus tlz~rr.ingi~r1~sstirsa in NT0423 as amicrobial-control agents, a new culture medium and culture condition were developed. Five mediadesignatzd as SWI I , SW14, SW23. SW32 and SW4I were prepared ~ : i t hv arious mixture ratio ofsoybean cake and wheat bran. It was founcl that in terms of the cell growth rate and development ofsporulation of B, thrri.il~girrl.sis strain NT0423 in all SW culture media were more efficient than those inGYS and in LB media. Total cell number in all SW media showed similar values, hut SW32 lnediilm wasthe most efficient in the development of spore, which amo~~ntetod 3.7 x 10XC FUImI. Also. at the pHranging frorn 6.2 to 7.3 in the mediiun~ no ad\:erse effect was not made in the culture of B. thur-ingicnsisstrain NT0423. The optimal volume (%) of SW32 mecliuni in a 5 1 fernientor was determined as 4 8\rolume of total niediuni. resulting ill growth (4.2 x 1OTCFUlrnl) of H. t1~~irir1,yirrz.ssit.vr ain NT0423. As H.t l i ~ t r i t ~ g iw~ a~s~ csuil~tu rcd in the shakc-flash and 5 1 fcrnientor. bacterial cells were yielded to 1 X 10"CFUIml and 5 x I O1oCFLJlml.FUIml and 5 x I O1oCFLJlml.

• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.265-272
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• 2023

Lignocellulosic biomass is essential to pretreatment because of having rigid structures and a lot of lignin. Among methods of pretreatment, using THF solvents has the advantage of being easy to reuse. THF (Tetrahydrofuran) used as a co-solvent with water or ionic solvent that is inexpensive and can remove lignin over a wide range of reaction conditions. NaOH (Sodium hydroxide) has been demonstrated to preferentially solvate lignin from cellulose. Thus, NaOH was used as a pretreatment co-solvent for the fractionation of lignin by destroying the ether bond to amend for hydrolysis and expand the surface area of cellulose and hemicellulose. In this experiment, lignin was removed by the NaOH/THF co-solvent pretreatment process to characteristics for the pretreatment and obtain the optimal levulinic acid conversion yield through the acid catalyst conversion process. the NaOH/THF co-solvent system was conducted in various ratios of co-solvent under a total of 16 conditions. And the temperature was 180 ℃ during to 60 mins. The optimum condition of co-solvent is NaOH 5 wt%/THF 90:10(v/v%), 76.8% glucan content was obtained through this co-solvent pretreatment, and 90.1% lignin was removed. In the acid catalyst conversion process, which is a subsequent pretreatment process, the experiment was conducted under the conditions of 30 to 90 min of reaction time and 160 ℃ to 200 ℃ reaction temperature. The optimum condition of acid catalyst conversion process is 60min reaction time under of 180 ℃, and it obtained 84.7% of levulinic aicd conversion yield.

• Journal of the Korean Wood Science and Technology
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• v.42 no.4
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• pp.428-438
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• 2014

Functional effects of cauliflower mushroom (Sparassis latifolia) have been magnified by various media and internal and external research papers, recently. So, optimum condition of wood chip particle size and cultivation method of high ${\beta}$-glucan content for bulk cultivation generalization of cauliflower mushroom farms researched. As a result, T7 (1~2 mm 25%, 2~4 mm 50%, over 4 mm 25%) media as mixed media of certain ratio of particle size, showed excellent growth at $11.5{\pm}1.0$ cm / 44 days. Also, production of fruit body found higher than control and marketable pileus part took 85% ratio. The ${\beta}$-glucan content at media composition condition showed 1.4~2.4 times higher content in stipe part than pileus part. Also, PCF300 medium found 59.5% highest ${\beta}$-glucan content in stipe part. While ${\beta}$-glucan content showed 33.0% low content in pileus part. Therefore it needed additional study that ${\beta}$-glucan content improved in pileus part. In conclusion, production of high ${\beta}$-glucan content cauliflower mushroom was possible by T7 condition (wood chip particle size: 1~2 mm 25%, 2~4 mm 50% and over 4 mm 25%, composition: corn powder, flour and 300 ppm yeast).

• Journal of Food Hygiene and Safety
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• v.23 no.2
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• pp.113-120
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• 2008

The influence of incubation temperature, pH and media components on bacteriocin production by Lactobacillus plantarum K11 were investigated. The highest activity was observed in MRS broth, but no bacteriocin activity was obtained in TSB. The bacteriocin was produced from the exponential growth phase and its activity also reached a maximum in MRS broth, but then dropped after 16 hr because of degradation by extracellular proteolytic enzymes or exhaustion of medium nutrients. The optimal temperature and pH for production of bacteriocin were $37^{\circ}C$ and pH 7.0 in MRS broth, respectively. The addition of 0.5 or 1.0% glucose and $0.5{\sim}1.5%$ lactose to MRS resulted in the increase of the bacteriocin production. With 0.5% NaCl and $K_2HPO_4$, the activities were significantly higher than that of control, respectively. However, increasing nitrogen sources such as beef extract, casein, and tryptone and salts such as $NH_4PO_4$, $MgSO_47H_2O$, and $MnSO_4H_2O$, had detected a negative influence upon the bacteriocin production. Consequently, because the bacteriocin produced by L. plantarum K11 was affected by various incubation conditions, the bacteriocin activity of L. plantarum K11 applied in food as a novel starter will be dependent on environmental factors such as fermentation conditions and food ingredients.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.169-175
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• 1980

These studies were conducted to induce the available mutant strains in acetic acid bacteria by the irradiation of UV-light and the treatment of N-methyl-N'-nitro-N'-nitrosoguanidine. 109 strains which were capable of producing acid in the ethanol containing medium were isolated from vinegar and Kimchi collected from the region of Daejeon city. From the collection T-50 strain was identified to have a strong fermentation power and selected as a mother strain for the study. Two mutants were obtained by treating T-50 strain with UV and NTG, and these mutants had a rapid acid production in the initial stage. The study was then made to compare the basic condition for acetic acid production of the mother strain and two mutant strains. The summarized results were as follows; 1. The isolated strain (T-50) was identified as Acetobacter aceti by Bergey's manual and Acetic acid bacteria (Tokyo Univ. press). 2. The selected strain was died completely when the strain was irradiated with 15 W UV-light at a distance of 45 cm for 160 seconds. 3. The mutants such as U-48 and N-67 were rapid in the acetic acid production at the initial stage compare to the mother strain. 4. Acetic acid formation by the shaking culture method was maximized in 2 days culture, and the optimal temperature for acetic acid production was $30^{\circ}C$. 5. Acetic acid was effectively produced by the addition of 0.1% ammonium sulfate as a nitrogen source and was also produced rapidly by the addition of 0.1% glucose.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.11
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• pp.1116-1122
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• 2008

The existing technology which is for recycling aggregate using dried swage sludge have been limited for practical application, because the properties of aggregate are not regular and don't meet the recycling aggregate standard. In this research, an innovative slag-producing technology is developed by addition of oyster shell, waste cast-sand and iron-rust as inorganic waste additives. The mixed slag with the additives was evaluated at the various ratio of CaO/SiO$_2$, SiO$_2$/Al$_2$O$_3$ and Fe$_2$O$_3$/SiO$_2$. When the waste sludge was melted at 1,400$^{\circ}C$ during 20 minutes, the optimal ratio of CaO/SiO$_2$ for the slag added the oyster shell, SiO$_2$/Al$_2$O$_3$ for added the waste cast-sand and Fe$_2$O$_3$/SiO$_2$ for added the iron-rust were 1.00, 3.00 and 0.60, respectively. At the optimal condition, the bulk density of the slag was 2.24 g/cm$^3$, 2.45 g/cm$^3$ and 2.73 g/cm$^3$, And the 24 h water adsorption was 4.72%, 1.44% and 0.37%, respectively. Therefore it is proved that adding the waste additives to the process of the slag production contributed for elevation of recycling aggregate properties. And also it is expected that production cost can be reduced by decreased melting temperature.

• Clean Technology
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• v.19 no.3
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• pp.264-271
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• 2013

In this study, we optimized the removal condition of contaminants attached on the scrap surface to recycle the scrap generated from the Zr alloy tube manufacturing process back to the nuclear grade. The main contaminant is remnant of watersoluble cooling lubricant that is used in the pilgering manufacture during the tube production, and it is assumed to be compressed and carbonized on the surface of tube. Zirlo alloy tube of ${\phi}9.50mm$, which has high occurrence frequency of scrap, was selected as the object to be cleaned, and cleaning abilities of reagents were evaluated by measuring the characteristics of contaminants remained and by analyzing the surface of the tube after cleaning process. For evaluation of each cleaning agent, we selected two types of sodium hydroxide series and three types of potassium hydroxide series. Furthermore, to confirm dependence on tempe-rature and ultrasonic intensities, cleaning at the room temperature, $40^{\circ}C$, and $60^{\circ}C$ was conducted, and results showed that higher the cleaning temperature and higher the ultrasonic intensity, better the cleaning effect. As a result of the bare-eye inspection, while the use of sodium hydroxide provided satisfactory condition on the tube surface, the use of potassium hydroxide series provided satisfactory condition on the tube surface only when the ultrasonic intensity was over 120 W. In the cleaning effect analysis using the gravimetric method, cleaning efficiency of sodium hydroxide series was as high as 97.6% ($60^{\circ}C$, 120 W), but since the tube surface condition was poor after the use of potassium hydroxide, the gravimetric method was not appropriate. In the analytical result of surface contaminants on the tube surface, C, O, Ca, and Zr were detected, and mainly C and O dominated the proportion of contaminants. It was also found that the degree of cleaning on the tube affected the componential ratio of C and O; if the degree of cleaning is high, or if cleaning is well-conducted, the proportion of C is decreased, and the proportion of O is increased. Based on these results, optimal cleaning for application in the industry can be expected by categorizing cleaning process into three steps of Alkali cleaning, Rinsing, and Drying and by adjusting cleaning parameters in each step.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.123-133
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• 2011

The objective of this study was to find optimal nutrient condition of container seedling production of two tropical species for high seedling quality. This study was conducted to investigate photosynthesis, chlorophyll fluorescence, chlorophyll contents, and growth performances of container seedlings of Eucalyptus pellita and Acacia mangium growing under four different fertilization treatments (Con., $0.5\;g{\cdot}l^{-1}$, $1.0\;g{\cdot}l^{-1}$, and $2.0\;g{\cdot}l^{-1}$ fertilization). E. pellita showed outstanding photosynthetic capacity, photochemical efficiency, and chlorophyll contents at $1.0\;g{\cdot}l^{-1}$ fertilization. Meanwhile, E. pellita showed the highest photosynthetic capacity, photochemical efficiency, and chlorophyll contents at $2.0\;g{\cdot}l^{-1}$ fertilization, as fertilization rate were increased, those of A. mangium increased. Like physiological characteristics, Both E. pellita at $1.0\;g{\cdot}l^{-1}$ fertilization and A. mangium at $2.0\;g{\cdot}l^{-1}$ fertilization were higher root collar diameter, height, biomass, and seedling quality index than other treatments. These results showed that E. pellita at $1\;g{\cdot}l^{-1}$ fertilization and A. mangium at $2.0\;g{\cdot}l^{-1}$ fertilization is optimal nutrient condition, respectively. Moreover, fertilization rate controlling is very important for growth and seedling quality of container seedling.