• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.1
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• pp.131-138
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• 2006

In this study, the optimum condition of pH was investigated on the hydrogen gas production under anaerobic fermentation process. The results of the experiment showed that the optimum condition was observed at pH 6, resulting in 1175.87 mL/L of hydrogen gas production rate and 22.51% theoretical hydrogen conversion ratio. Hydrogen gas production rate and theoretical hydrogen conversion ratio were 901.77 mL/L and 17.48 % respectively at pH 5. At pH 7 and 8, the production rate of hydrogen gas was little low as 82.15 mL/L. Among the organic acids from the sucrose fermentation, propionate was observed as the dominant acid at pH 7 and 8 but butyrate was the dominant at pH 5 and 6.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.77-82
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• 2013

The growth and removal capacity of nitrogen and phosphorus of Chlorella vulgaris were evaluated in artificial wastewater with different nitrogen and phosphorus concentrations as element growing components for microalgae growth. The nitrogen concentration was varied in 9, 15, 30 and 60 mg-N/L with fixed phosphorus concentration of 3 mg-P/L. The growth and phosphorus removal capacity of C. vulgaris were high at initial nitrogen concentration of 15 and 30 mg-N/L, and the corresponding N/P ratios calculated were 5 and 10. In the case of varying in 1.5, 3, 6 and 10 mg-P/L of phosphorus concentration with fixed nitrogen concentration of 30 mg-N/L, the growth and removal capacity of nitrogen and phosphorus were excellent with phosphorus concentration of 3 and 6 mg-P/L. The corresponding N/P ratios were shown as 10 and 5. Therefore, the appropriate N/P ratio was concluded between 5 and 10 for wastewater treatment using C. vulgaris.

• Proceedings of the Korean Society of Crop Science Conference
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• 1997.05a
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• pp.76-77
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• 1997

• Journal of Radiation Protection and Research
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• v.21 no.2
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• pp.107-115
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• 1996

An electrolytic enrichment technique was used to measure low levels of tritium in seawater around the Korean peninsula. Tritium concentrations were determined for surface seawater samples collected from the East Sea, the South Sea, and the Yellow Sea. The tritium concentrations in surface seawater samples from the study area ranged from $0.12 BqL^{-1}\;to\;1.50BqL^{-1}$ with a mean value of $0.60{\pm}0.35 BqL^{-1}$. The means of the tritium concentration were $0.54{\pm}0.30 BqL^{-1}$ for the East Sea, $0.48{\pm}0.35 BqL^{-1}$ for the South Sea, and $0.77{\pm}0.32 BqL^{-1}$ for the Yellow Sea. The tritium concentrations in the sea areas did not show much difference no matter where the samples were taken. Due to the limited number and distribution of sampling points, no systematic change in tritium levels with latitude was observed. Measured tritium levels were similar to those observed in other data collected near Japan, but higher than mid-Pacific Ocean measurements.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.275-278
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• 2000

Bacillus polyfermenticus SCD which is commonly called as 'Bispan strain' has been appropriately used for the treatment of long-term intestinal disorders, since the live strains in the form of active endospores can successfully reach the target intestine. The goal of this study were to get the novel bispan mutant strain and to get higher spore number of bispan mutant in submerged fermentation. Bispan mutant KD21 was obtained using NTG mutagenesis of bispan strain, and bispan mutant was cultivated in 5 L jar fermenter. In this study, productivity and sporulation rate of the bispan mutant KD2l showed approximately 77% increase when compared with bispan strain.

• Korean Journal of Plant Resources
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• v.16 no.1
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• pp.8-14
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• 2003

This study was aimed to obtain basic information on the characteristics of local cultivars of burdock(Arctium lappa L.) grown in Yeong-Nam region. The characteristics of seeds were shown a remarkable diversity among the local cultivars. Germination rate was the highest at 25$^{\circ}C$ and Munkyong' as the highest germination rate(42.2%) at l0$^{\circ}C$ respectively. In Youchon' and 'Chilgok', about 10％ was bolted but the other was rarely or none. The range of root length was 62∼77cm and lateral root number was maximum 5.5('Koryong') and minimum 0.3('Songju). 'Chongdo I' contents 14.2mg/100g of tannin in root and 'Kyongsan', 'Koryong', 'kyongiu',’ Kumi' and 'Haman' taste not bitter in leaves.

• Korean Journal of Pharmacognosy
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• v.52 no.2
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• pp.77-83
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• 2021

The number of people suffering from diabetes have been increased around the world. In this study, we investigated the antidiabetic and antioxidant effects of Anthriscus sylvestris(L.) Hoffm and its main compounds. It was divided into root(R) and aerial part(AP) for comparative analysis. Total polyphenol, total flavonoid content was higher in AP extract, but nodakenin content was higher in R(1169.13 ± 6.00 mg/g) extract. Antioxidant activity was also higher in AP extract. To compare antidiabetic efficacy, we analyzed the effects of R and AP extracts on ɑ-glucosidase inhibition(AGI), dipeptidyl peptidase-4(DPP-4) and protein tyrosine phosphatase(PTP)1B activity. R and AP extracts showed similar effects on AGI and DPP-4 activity in a concentration dependent manner, and there was no effect on PTP1B activation. Glucose uptake(139.51 ± 3.19%) in 3T3-L1 cells was more effective in the AP extract-treated group than the positive control, rosiglitazone, group. Both R and AP extracts were effective in protecting against pancreatic beta cell damage caused by hyperglycemia. These results suggest that Anthriscus sylvestris(L.) Hoffm. could be used as a candidate for diabetes treatment.

• Journal of Microbiology and Biotechnology
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• v.31 no.9
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• pp.1262-1271
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• 2021

L-Malic acid (L-MA) is widely used in food and non-food products. However, few microorganisms have been able to efficiently produce L-MA from xylose derived from lignocellulosic biomass (LB). The objective of this work is to convert LB into L-MA with the concept of a bioeconomy and environmentally friendly process. The unique trifunctional xylanolytic enzyme, PcAxy43A from Paenibacillus curdlanolyticus B-6, effectively hydrolyzed xylan in untreated LB, especially corn hull to xylose, in one step. Furthermore, the newly isolated, Acetobacter tropicalis strain H1 was able to convert high concentrations of xylose derived from corn hull into L-MA as the main product, which can be easily purified. The strain H1 successfully produced a high L-MA titer of 77.09 g/l, with a yield of 0.77 g/g and a productivity of 0.64 g/l/h from the xylose derived from corn hull. The process presented in this research is an efficient, low-cost and environmentally friendly biological process for the green production of L-MA from LB.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.9
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• pp.1113-1119
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• 2007

Water extracts from root, stem and leaf of Ailanthus altissima were utilized to determine antioxidant properties such as electron donating ability (EDA), nitrite scavenging ability, superoxide dismutase (SOD)-like activity, and the inhibitory activities of xanthine oxidase (XO) and tyrosinase. The EDA of root extract was the highest as 77.33% at 0.5 mg/mL concentration and that of stem extract was 70.01% at 1.0 mg/mL. The nitrite scavenging ability of leaf extract revealed the highest effect as 95.18% at pH 1.2, 1.0 mg/mL while those of stem and root extracts were 55.17% and 33.33%, respectively. The leaf extract showed the highest SOD like activity as 26.77% at 1.0 mg/mL, the measurement of root extract was 3.82% and that of stem extract was not effective. All kinds of extracts had strong inhibitory activities on XO of over 92% at 1.0 mg/mL. The highest activity on tyrosinase inhibition was obtained from leaf extract of 16.33% at 2.0 mg/mL. The results indicated that among the three extracts, the leaf extract has a strong and extensive antioxidant activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1599-1605
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• 2005

The object of this study is to develop the method for differentiating fresh meat from frozen meat by using the measurement of the mitochondrial malate dehydrogenase in the Korean native cattle. The principle of this experiment is based on the fact that the enzyme proteins associated with mitochondrial membrane could be released by freezing. The methods of differentiating fresh meat from thawed, frozen meat were studied by measurements of mitochondrial malate dehydrogenase activity of meat press juice. Fresh and frozen beef were stored at 4, -4, -18 and -77$^{\circ}C$ for 15-day storage period. A meat press machine using air pressure was manufactured especially for these experiments, and sufficient amount of drip (about 0.15 mL/g) from 1.5 g of beef sample was efficiently obtained under a pressure of 8 kg/$cm^{2}$ generated by the meat pressing machine. The mitochondrial malate dehydrogenase activities of frozen meat drip i년ices stored at -18 and -77$^{\circ}C$ were significantly higher than those of fresh and frozen meat samples at -4$^{\circ}C$ (p < 0.05) during 10-min reaction period. However, the enzyme activities of the frozen meat drip juices (-18 and -77$^{\circ}C$) disappeared after 5 minutes of the reaction, which was not observed from the fresh and -4$^{\circ}C$ frozen meats. The enzyme activity maintained until 12 minutes for the fresh and -4$^{\circ}C$ frozen meats. From these results, the mitochondrial malate dehydrogenase could be considered as an indicator to differentiate fresh beef from frozen one.