• Food Science and Preservation
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• v.18 no.4
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• pp.604-611
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• 2011

Several wild yeasts were isolated from Korean grape varieties before and during spontaneous fermentation. Among them, four strains were isolated based on the alcohol content and flavor production in wine after fermentation of apple juice. In this study, the four yeast strains were identified and characterized. PCR-restriction fragment length polymorphism analysis of ITS I-5.8S-ITS II region with restriction endonuclease Hae III and Hinf I resulted in that all the strains showed a typical pattern of Saccharomyces cerevisiae. Pulse field gel electrophoresis showed three different chromosome patterns with a same band between strains SS89 and SS812. When ITS I-5.8S-ITS II sequences of the four strains were compared with one another, they were similar to those of Saccharomyces cerevisiae CBS 4054 type strain. Identity of the sequences was higher than 97% with those of the type strain. Phylogenetic analysis showed based on the sequences showed they were genetically closed to the type strain. The four identified strains were tested in a medium containing 200 ppm potassium metabisulfite, and the MM10 and WW108 inhibition rates resulted at up to 24 h. The four strains were tested at an incubation temperature of $30^{\circ}C$. The 30% sugar concentration in the medium (w/v) showed the highest growth in 36 h, especially in the case of SS89, which was close to growth 40. The four strains were tested in an 8% ethanol medium (v/v). Alcohol tolerance was initially kept in the incubation process. The strains began to adapt, however, to the exceeded resistance. The four strains showed the lowest inhibition rate at 24 h.

• Food Science and Preservation
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• v.24 no.8
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• pp.1129-1137
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• 2017

The fringe tree, Chionanthus retusus (Oleaceae) has been used as a natural remedy that helps a paralytic stroke, dementia, phlegm and malaria. This study was conducted to investigate the antioxidant and anti-aging activities of water extracts obtained from the flesh of C. retusus by reflux extraction at room temperature and $80^{\circ}C$, and pressure heating extraction at $110^{\circ}C$, for an increment of their practical use. The highest extraction yield from the flesh of C. retusus was 67.94% extract by pressure heating extraction at $110^{\circ}C$. The content of total polyphenol compounds was the highest by 72.71 mg/g in $80^{\circ}C$ extract by reflux extraction. The highest content of total flavonoid compounds was 7.60 mg/g at $110^{\circ}C$ extract. The results of soluble protein and reducing sugar contents showed the highest content of 4.93 mg/g and 46.77 mg/g in $110^{\circ}C$ extract, respectively. In the analysis of DPPH radical scavenging activity, all extracts showed an excellent effect of 92% in 1.0 mg/mL concentration. The highest effect of ABTS radical scavenging activity was 88.67% at $110^{\circ}C$ extraction in 1.0 mg/mL concentration. Nitrite scavenging ability was the highest as 66.16% at $110^{\circ}C$ extract at pH 1.2 and 1.0 mg/mL concentration. The results of SOD-like activity and xanthine oxidase inhibition activities showed the highest effect of 14.95% and 59.45% at $110^{\circ}C$ extract in 1.0 mg/mL, respectively. Tyrosinase inhibition activity for whitening effect was the highest of 35.31% at $85^{\circ}C$ in 1.0 mg/mL. In the analysis of anti-aging effect, collagenase and elastase inhibition activity showed the highest effects of 37.78% at $110^{\circ}C$ and 20.39% at $80^{\circ}C$, respectively. All results of antioxidant activities and anti-aging effects increased along with the concentration increases. These results indicated that the extracts extracted from the flesh of C. retusus at $80^{\circ}C$ and $110^{\circ}C$ have a large amount of useful ingredients, an excellent antioxidant activity, like as DPPH and ABTS radical scavenging activity, and anti-aging effects to develop functional products than those of $25^{\circ}C$.

• Journal of Animal Science and Technology
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• v.50 no.3
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• pp.391-400
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• 2008

Odor management is significantly concerned with sustainable livestock production because odor nuisance is a primary cause for complaint to neighbors. This study was conducted to measure the concentration of odorous compounds, odor intensity, and odor offensiveness at unit process in animal waste treatment facility combined composting and methane fermentation process by an instrumental analysis and direct olfactory method. Ammonia, sulfur-containing compounds, and volatile fatty acid were analyzed at each process units and boundary area in summer and winter, respectively. Higher concentration of odorants occurred in the summer than in the winter due to high ambient temperature. The maximum concentration of odorants was detected in composting pile when mixed manure was being turned followed by inlet, curing, outlet, and screen & packing process. Highest concentration of detected odorous compounds was ammonia ranging from 3.4 to 224.7 ppm. Among the sulfur-containing compounds measured, hydrogen sulfide was a maximum level of 2.3 ppm and most of them exceeded reported odor detection thresholds. Acetic acid was the largest proportion of VFA generated, reaching a maximum of 51 to 89%, followed by propionic and butyric acid at 1.9 to 35% and 1.8 to 15%, respectively. Malodor assessment by a human panel appeared a similar tendency in instrumental analysis data. Odor quotient for predicting major odor-causing compounds was calculated by dividing concentrations measured in process units by odor detection thresholds. In the composting process, hydrogen sulfide, ammonia, dimethyl sulfide, and methyl mercaptan were deeply associated with odor-causing compounds, while the major malodor compounds in the inlet process were methyl mercaptan, hydrogen sulfide, and butyric acid.

• Applied Biological Chemistry
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• v.16 no.1
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• pp.1-11
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• 1973

In order to obtain the basic informations on the production of single cell protein from ethanol, 145 yeast strains utilizing ethanol as a sole carbon source were isolated from 32 soil samples in Korea. A yeast strain showing the highest cell yield among the isolated strains was selected and identified. The optimum culture condition, utilization of other carbon sources and the cultural characteristics for the selected yeast, and the chemical analysis of the yeast cell composition, and utilization of ethanol by the selected yeast were investigated. All the culture was carried out in the shaking flasks. The results obtained were as follows: 1. The selected yeast strain was identified as Debaryomyces nicotianae-SNU 72. 2. The optimum composition of the medium for the selected yeast is : Ethanol 40 ml, Urea 0.5 g, Potassium phosphate (dibasic) 0.5 g, Ammoium phosphate (monobasic) 0.15 g, Magnesium sulfate 0.05 g, Calcium chloride 0.01g, Yeast extract 0.005 g, Tap water 1000 ml. 3. The optimum pH was 5.0-5.5, the optimum temperature $30-33^{\circ}C$ and the aerobic state was unimportant. 4. Utilization of methanol, n-propanol, iso-propanol, n-butanol, iso-butanol, tert-amyl alcohol and acetic acid by the selected yeast was very weak. So substitution of the subtrate was thought to be impossible. 5. Studies on the propagation of the yeast cells showed that the lag phase of the yeast cells lasted 16 hours, and the logarithmic growth phase extended 16 to 28 hours. The specific growth rate was about $0.19\;hr^{-1}$ and the doubling time was 3.6 hours during the logarithmic growth phase. 6. As the result of the chemical analysis of the dry yeast cells, the content rate of the crude protein was 55.19 %, the content of others was similar to the average content of the yeast component. 7. After 34 hours cultivation, under the optimum culture condition investigated, the dry cell yield against the amount of the added ethanol was 53.4 % (W/V%), the dry cell yield against the amount of the utilized ethanol was 73.6 % (W/V%), the evaporation rate of ethanol was about 19.1 %.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.4
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• pp.45-56
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• 2016

In this study, an analysis has been conducted on the evaluation criteria of current G-SEED(Green Standard for Energy and Environmental Design) and on the 78 buildings, certified by G-SEED, for 3 years from November, 2012 to November, 2015. Based on the results of this analysis, four issues are driven and proposed hereinafter. Issue 1 : Nowadays, the psychological proportion of landscape architecture in building is getting greater than ever so that it shows reliable reduction of carbon dioxide. Therefore, so far as the eight kinds of buildings are concerned, the evaluation items of G-SEED must include those of landscape architecture mandatorily through its enlargement. Issue 2 : It is undesirable factor that inhibits precise evaluation on landscaping area to let other areas appraise landscape architecture because it requires outstanding professionalism. So, G-SEED should not only ensure landscaping professionalism for the correct evaluation but also let landscape area participate in assessing other areas. Issue 3 : Many previous researches turned out that landscape planting technique has excellent effect on saving energy and reducing temperature of buildings. Thus, landscape planting technique of landscape area is required to be one of the evaluation items of energy sector. Issue 4 : Tree management also has to be newly included as one of the evaluation factor for the maintenance relating to the landscape architecture. G-SEED, enacted and enforced by the Green Building Creation Support Act in 2013, surely is effective system to reduce carbon dioxide in buildings. This is a special Act in its nature that is superior to Construction Law and must be observed by all means to construct buildings. Under the umbrella of this legal system, various of researches and products are contributing to creating new jobs in construction area. However, it is a well-known fact that landscape architecture area has shown less interest on this Act than that of construction area. In conclusion, it is necessary that landscape industry should conduct continuous researches on G-SEED and pay more attention to the Act enough to harvest related products and enlarge its work area.

• Korean Journal of Ecology and Environment
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• v.42 no.2
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• pp.260-269
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• 2009

Hwabuk Dam has been under construction to reduce flood damage in Nakdong River watershed and to supply stable water for middle area of Gyeongbuk Province. Therefore, fish investigation in up and downstream of the dam was conducted from 2004 to 2008 in order to determine any negative effect on fish community due to dam construction and to use as fundamental data for conserving species diversity and maintaining stream health. According to data analysis on water quality, temperature, dissolved oxygen, pH, suspended solids, and total E-coli had seasonal variation, but they did not significantly differ in sites. However, biological and chemical oxygen demand, chlorophyll-a, nitrogen, and phosphorus representing organic matter and nutrient concentration were higher in upper site and decreased to lower site so that they differed by site. Concentration of arsenic among the heavy metals was less than 0.05 mg $L^{-1}$, which is regulated for protection of human health in water quality standard, except for 0.092 mg $L^{-1}$ in June 2005. During the study period, the total number of fish caught from the 6 sites was 10,263 representing 7 families 19 species. Among them, dominant and subdominant species were Korean chub (Zacco koreanus, 62.5%) and Chinese minnow (Rhynchocypris oxycephalus, 10.6%) which inhabit mostly in mid and upper streams, Korea. Among the 19 species, Korean endemic species were 9 species (47.4%) including Korean slender gudgeon (Squalidus gracilis majimae), Korean dark sleeper (Odontobutis platycephala), and Korean shiner (Coreoleuciscus splendidus). There was several individuals of the $1^{st}$-class endangered species, Naktong nose loach (Koreocobitis nahtongensis), caught in 2005${\sim}$2007, and no introduced species of fish was found in entire sampling period. According to result of community analysis, dominance index decreased toward lower site, but diversity and richness indices increased toward lower site. The equation of length-weight relationship on the dominant species was TW=0.000003$(TL)^{3.2603}$. The parameter b in the equation was greater than 3.0 indicating good nutritional condition in the populations. Compared to populations of Korean chub in other streams, the population in Hwabuk Dam watershed had higher mean of condition factor by size indicating better growth rate. With fish fauna and multi-metric health assessment model in each sampling attempt, index of biotic integrity (IBI) was evaluated and it resulted mostly in good (26${\sim}$35) and excellent (36${\sim}$40) condition in all sites, and the mean of IBI was the highest in site 5. The results indicate that it is very important to study not only environmental impact assessment with fish composition but also stream health assessment in order to conserve healthy aquatic ecosystem.

• Resources Recycling
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• v.15 no.4 s.72
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• pp.3-12
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• 2006

The feasibility for the employment of manganese nodule as an adsorbent for $SO_{2}$ gas has been investigated. The specific surface area of manganese nodule particle, which used in the experiments, was ca. $221.5m^{2}/g$ and the content of sulfur in manganese nodule was observed to significantly increase after $SO_{2}$ was adsorbed on it. The EPMA for the distilled water-washed and methanol-washed manganese nodule particle after $SO_{2}$ adsorption showed that its sulfur content was slightly decreased to 14.7% and 13.1% respectively, from 15.4% before washing. The XRD analysis of manganese nodule showed that todorokite and birnessite, which are manganese oxides, and quartz and anorthite were the major mineralogical components and weak $MnSO_{4}$ peaks were detected after $SO_{2}$ was adsorbed on manganese nodule. For an comparative investigation, limestone was also tested as an adsorbent for $SO_{2}$, however, no peaks for $CaSO_{4}$ were found by XRD analysis after the adsorption of $SO_{2}$. As the size of adsorbent increased, time for breakthrough was decreased and the adsorbed amount of $SO_{2}$ was also diminished. The $SO_{2}$ adsorption was hindered when its flow rate became high and the adsorption capacity of manganese nodule was observed to be superior to that of limestone. In addition, the mixture of manganese nodule and limestone did not show an increase in the adsorption of $SO_{2}$. Finally, as the temperature was raised, the adsorbed amount of adsorbate on manganese nodule was found to be decreased.

• Journal of Wetlands Research
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• v.23 no.4
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• pp.317-326
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• 2021

The present study was carried out with a view to understand the distribution and ecology of Clihton retropictus (Martens, 1879), a class II endangered wildlife designated and protected by the Ministry of Environment, Republic of Korea, and to suggest the effective conservation and management measures for this species and its habit. First, the distribution of Clihton retropictus was investigated nationwide, and environmental factors such as salinity and substratum were analyzed in consideration of the ecological characteristics of this species. In addition, the individual size, density, and movement of Clihton retropictus per each district surveyed were analyzed. Due to its nature of inhabiting in the brackish water zone, the analysis showed that the salinity of this species was 0.7 ~ 16.6‰ at low tide and 1.0 ~ 17.3% at high tide. It was learned from the analysis of substratum that its composition in each river under investigation was slightly different, but most of substratum had a higher composition ratio than gravel (pebble, 16 ~ 64 mm). On the other hand, the size of each individual was checked by measuring the length of its diameter, and there was almost no change in the individual when the inhabited range of Clihton retropictus was short. However, there was tendency that the longer the habitat range, the bigger the individual size. From surveying the population density by season, it was made clear that, during the summer (July to August) and fall (September to October), the density was relatively higher while the number of individuals decreased significantly during winter (November to December) when the water temperature was lowered. In an effort to effectively establish conservation and management measures, the moving distance was measured, and it became known that, during the surveys in summer and fall when the individuals were active, the individuals moved in more distances than during the winter survey. The results of this study are expected to be utilized as basic data for establishing effective management plans such as creation of habitats for Clihton retropictus, its migration projects and selection of migration destinations which get unavoidable due to development projects.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.328-334
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• 2021

This study was conducted to analyze the effect of fog cooling during daytime and heatpump cooling at night in greenhouses in summer. During daytime, the average temp. and RH of the control greenhouse which had shading screen were 32.1℃ and 59.4%. and the average temp. and RH of the test greenhouse which had fog cooling were 30.0℃ and 74.3%. At this time, the average outside temp. and RH were 31.4℃ and 57.7%. So, the temp. of the control was 0.7℃ higher than outside temp., but the temp. of the test was 1.4℃ lower than outside and 2.1℃ lower than control. The average RH was 74.3% in the test and 59.4% in control. The average temp. and RH of the control greenhouse which had natural ventilation at night were 25.2℃ and 85.1%, and the average temp. and RH of the test greenhouse which had heat pump cooling were 23.4℃, 82.4%. The average outside temp. and RH at night were 24.4℃ and 88.2%. The temp. of the control was 0.8℃ higher than outside temp., but the temp. of the test was 1.0℃ lower than outside and 1.8℃ lower than control. The average RH was 82.4% in test and 85.1% in control greenhouse. There was no significant difference between the plants growth eight weeks after planting. But after the cooling treatment, the values of stem diameter, plant height, chlorophyll in test were higher than control. The total yield was 81.3kg in test, 73.8kg in control, so yield of test was 10.2% higher than control. As a result of economic analysis, 142,166 won in profits occurred in control greenhouse, but 28,727 won in losses occurred in test greenhouse, indicating that cooling treatment was less economical.

• Journal of Food Hygiene and Safety
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• v.33 no.6
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• pp.466-473
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• 2018

An analytical method of sodium polyacrylate in processed food products was developed and monitored by using size-exclusion chromatography. GF-7M HQ column and UV/VIS detector were selected based on peak shape and linearity. Flow rate, column oven temperature, and mobile phase were selected as 0.6 mL/min, $45^{\circ}C$, and 50 mM sodium phosphate buffer of pH 9.0, respectively. Samples for analysis of sodium polyacrylate were extracted with 50 mM sodium phosphate buffer of pH 7.0 for 3 hr at $20^{\circ}C$ and 150 rpm. Analytical method validation revealed proper selectivity and calibration curve was selected in the range of 50-500 mg/L, and correlation coefficient of calibration curve was more than 0.9985. Limit of detection of sodium polyacrylate was 10.95 mg/kg and limit of quantification was 33.19 mg/kg. Accuracy and coefficient of variation for sodium polyacrylate analysis was 99.6-127.6%, 3.0-8.3% for intra-day and 94.3-121.9%, 1.3-2.6% for inter-day, respectively. Sodium polyacrylate was detected in 40 samples among monitored 125 processed food products. Detected contents were less than 0.2%, limited by the Food Additives Code. Results suggest the established size-exclusion chromatography method could be used to analyze sodium polyacrylate in processed food products.