• Korean Journal of Soil Science and Fertilizer
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• v.30 no.2
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• pp.189-195
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• 1997

A phosphate solubilizing bacterium (PSB) possessing a high ability to solubilize hydroxyapatite (HA) was isolated from the rhizosphere of wheat. The PSB markedly developed clear zones after inoculating for 36 hours at $30^{\circ}C$. This bacterium was identified as Enterobacter agglomerans through API 20E system and Biolog$^{TM}$ analysis. The values of similarity and distance coefficient from authentication trial of the strain were 0.656 and 4.79 respectively. High performance liquid chromatography (HPLC) of the products of this strain indicated that this strain excretes maily oxalic acid with som other organic acids. During the incubation period of E. agglomerans, the pH values showed an inverse correlation ($r^2=0.933^{**}$) with solubilization of inorganic phosphate. Acid phosphatase activity of the strain was 10-15 times greater than alkaline phosphatase activity. Alkaline phosphatase activity had almost constant near zero activity across time. The population of E. agglomerans greatly increased during the first day of inoculation ; however, it drastically decreased thereafter.

• The Korean Journal of Community Living Science
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• v.20 no.2
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• pp.181-191
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• 2009

This study was conducted to examine the distribution status, the physicochemical composition, and the physiological activity of Spergularia marina grown in the western region in Jeon-Ra-Nam-Do, looking for its potential as a local specialty goods. The amount sold of Spergularia marina to different areas from a rural market place was examined during April, 2008. The proportions of Spergularia marina are as follows; Yeongam(30.5%), Muan(24.3%), Naju(20.3%), Hampyeong(18.0%), and Haenam(7.0%), which were shown higher than those of Pimpinella brachycarpa. Total vitamin C and total chlorophyll contents in Spergularia marina were 68.61mg/100g DW and 58.11mg/g DW, respectively. Total amino acid contents were 331.94mg/100g DW and 20 kinds of amino acids were separated and classified. The contents of inorganic matters in Spergularia marina were as follows; Na(64.23mg/L), Mg(15.88mg/L) K(9.99mg/L), Ca(3.83mg/L). The total phenol and the total flavonoid contents of methanol extracts from Spergularia marina were 41.7mg/L and 18.9mg/L, respectively, with an extracting concentration of 2,000mg/L. The nitrite scavenging activity was highest (83.4%) in hot water extract. These results may be useful as basic data for using Spergularia marina as a local specialty goods.

• Membrane and Water Treatment
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• v.9 no.3
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• pp.137-146
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• 2018

Soil washing is one of the most frequently used remediation technologies for heavy metal-contaminated soils. Inorganic and organic acids and chelating agents that can enhance the removal of heavy metals from contaminated soils have been employed as soil washing agents. However, the toxicity, low removal efficiency and high cost of these chemicals limit their use. Given that humic substance (HS) can effectively chelate heavy metals, the development of an eco-friendly, performance-efficient and cost-effective soil washing agent using a nano-scale chelator composed of HS was examined in this study. Copper (Cu) and lead (Pb) were selected as target heavy metals. In soil washing experiments, HS concentration, pH, soil:washing solution ratio and extraction time were evaluated with regard to washing efficiency and the chelation effect. The highest removal rates by soil washing (69% for Cu and 56% for Pb) were achieved at an HS concentration of 1,000 mg/L and soil:washing solution ratio of 1:25. Washing with HS was found to be effective when the pH value was higher than 8, which can be attributed to the increased chelation effect between HS and heavy metals at the high pH range. In contrast, the washing efficiency decreased markedly in the low pH range due to HS precipitation. The chelation capacities for Cu and Pb in the aqueous phase were determined to be 0.547mmol-Cu/g-HS and 0.192mmol-Pb/g-HS, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.2
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• pp.198-202
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• 2006

An experiment was conducted to investigate the effect of phytase, organic acids and their interaction on body weight gain, feed consumption, feed conversion ratio, carcass yield and tibia ash. A total of 680 three-day old Japanese quail chicks (Coturnix coturnix japonica) were assigned to 20 battery brooders, 34 chicks in each. The experimental period lasted 35 days. The treatment groups employed were: 1) a positive control which included 3.5 g available phosphorus (AP)/kg diet and 10 g Ca/kg diet; 2) a negative control which included 2 g AP/kg diet and 8 g Ca/kg diet, 3) negative control diet supplemented with either 300 FTU phytase/kg diet (phytase) or 4) 2.5 g organic acid (lactic acid+formic acid)/kg diet (organic acid); or 5) 300 FTU phytase/kg diet+2.5 g organic acid/kg diet (phytase+organic acid). All birds were fed with the positive control diet for a week and then transferred to the dietary treatments. At the end of the study, there were no differences (p>0.005) among the groups in body weight, weight gain, feed consumption, feed conversion ratio and carcass yield. Tibia ash, however, was reduced (p<0.001) for quails fed the negative control diet containing a low-level of AP compared to the positive control diet containing adequate AP. The addition of phytase, organic acid or phytase+organic acid to the diets containing the low-level of AP improved (p<0.001) tibia ash. On the other hand, an extra synergistic effect of phytase and organic acid on tibia ash was not determined. This study demonstrated that it may be possible to reduce supplemental level of inorganic P with phytase and/or organic acid supplementation for quail diets without adverse effect on performance and tibia ash.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.3
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• pp.278-282
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• 2006

The powdered boil-dried oyster (C), the powdered smoke-dried oyster (OS-1) and the powdered smoke-dried oyster scrap (OS-2) were examined for their taste-active components, quality characteristics for potential utilization as a natural flavoring substance. The free amino acid level of OS-l and OS-2 were 395.6 mg/100 g and 551.5 mg/100 g, respectively, and that of betaine of OS-1 and OS-2 were 164.6 mg/100 g and 214.9 mg/100 g, respectively. The contents of inorganic ions were rich in Na, K, P, Ca and Mg in that order. Major free amino acids were taurine, glutamic acid, proline, alanine and glycine. The extract condition of the OS-1 and OS-2 the instant soup was the most appropriate at $98^{\circ}C$ for 1-5 min. The hot water extract of OS-1 and OS-2 with additives such as salt, sugar, pepper and onion powder had a good organoleptic qualities compared with the conventional flavoring substances in a local market. We conclude that powdered smoke-dried oyster and its scrap can be commercialized.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.148-151
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• 1997

Platycodon root contains abundant pharmaceutical substances and is widely used as a food and a medicinal herb. To identify the major components of the three-year-old and the 24-year-old platycodon roots cultivated in a local farm were analyzed and compared with their chemical compositions prior to their pharmaceutical substances, which were used as the fundamental data. There were no differences in chemical composition, inorganic compositions and fatty acid compositions between the 24-year-old and three-year-old roots. Total amino acid contents were 375.8 mg% and 891.6 mg% in the 24-year-old and three-year-old platycodcon roots, respectively. Sixteen species of amino acid were identified by amino acid autolyzer except cysteine both in the 24-year-old and three-year-old roots. Linoleic acid, which was the highest fatty acid contained both in the 24-year-old and three-year-old roots, was estimated to be 48.7% and 39.1% of total fatty acids, respectively.

• Korean Journal of Microbiology
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• v.32 no.4
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• pp.252-257
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• 1994

A new hydrogen sulfide-oxidation bacterium, Thiobacillus sp. was isolated from waste coal mine water around Hawsun in Chunnam province. The isolate was motile gram-negative rod shape, formed spore and grew up to be aerobically facultative chemolithotroph by using energy released from the oxidation of reduced inorganic sulfur compounds. It could assimilate various kinds of organic compounds and grew well upon thiosulfate-supplemented basal medium. To the lelvel of 32 mM in thiosulfate concentration, thiosulfate in itself was utilized as energy source for growth. However, from those of the higher concentration than 32 mM, thiosulfate functioned specifically as the substrate inhibitor rather than as the energy source. It was found that the optimum thiosulfate concentration for growth was 32 mM. The G+C content of the DNA was 65.0 mol%. The isolate had 16 : 1 + 17$_{cyc}$, 16 : 0 as their major non-hydroxylated cellular fatty acids, 3-OH 12 : 0 as a hydroxylated fatty acid and also contained unidentified $C_{18}$ branched fatty acid. The ubiquinone system in the respiratory chain was Q-9. Based on the physiological and biochemical characteristics, the isolate was assigned to a novel species of the genus Thiobacillus sp. iw.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.782-786
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• 2001

The taste characteristics and functionality of low-utilized small longfinned squid as affected by two stage enzyme hydrolysis were examined. In taste active-components, total free amino acid contents in hot-water and autolytic extract, two stage enzyme hydrolysate (TSEH) of longfinned squid were 2,792.5 mg%, 8,393.8 mg% and 9,186.1 mg%, respectively. The major free amino acids were Pro, Leu, Glu, Tau, Lys, Arg, Phe, Val and Ile. As for quarternary ammonium bases, betaine was the principal component (593.8 mg%) and also contents of TMAO, AMP in longfinned squid TSEH were 234.8% mg% and 51.0 mg%, respectively. The major inorganic ions in TSEH were Na(874.0 mg%), K (398.2 mg%), Cl (1,213.1 mg%) and PO$_4$(995.9 mg%). From the results in sensory tests, TSEH was superior to other extracts on the aspects of taste characteristics such as umami intensity, sweetness, taste harmony and transparency of extract. Also TSEH of longfinned squid revealed very higher Angiotensin-I converting enzyme inhibition ratio (92.1%) than those of hot-water and autolytic extract.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.3
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• pp.310-321
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• 2019

Objectives: The purpose of this study was to investigate types and characteristics of chemical substances used in LCD(Liquid crystal display) panel manufacturing process. Methods: The LCD panel manufacturing process is divided into the fabrication(fab) process and module process. The use of chemical substances by process was investigated at four fab processes and two module processes at two domestic TFT-LCD(Thin film transistor-Liquid crystal display) panel manufacturing sites. Results: LCD panels are manufactured through various unit processes such as sputtering, chemical vapor deposition(CVD), etching, and photolithography, and a range of chemicals are used in each process. Metal target materials including copper, aluminum, and indium tin oxide are used in the sputtering process, and gaseous materials such as phosphine, silane, and chlorine are used in CVD and dry etching processes. Inorganic acids such as hydrofluoric acid, nitric acid and sulfuric acid are used in wet etching process, and photoresist and developer are used in photolithography process. Chemical substances for the alignment of liquid crystal, such as polyimides, liquid crystals, and sealants are used in a liquid crystal process. Adhesives and hardeners for adhesion of driver IC and printed circuit board(PCB) to the LCD panel are used in the module process. Conclusions: LCD panels are produced through dozens of unit processes using various types of chemical substances in clean room facilities. Hazardous substances such as organic solvents, reactive gases, irritants, and toxic substances are used in the manufacturing processes, but periodic workplace monitoring applies only to certain chemical substances by law. Therefore, efforts should be made to minimize worker exposure to chemical substances used in LCD panel manufacturing process.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.836-844
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• 2010

This study was carried out to investigate plant characteristics and nutritional components of the genetically modified (GM) Chinese cabbage and its control line grown in the central and northern parts of Korea in order to establish the evaluating protocol and standard assessment. The GM and non-GM Chinese cabbage was planted with normal and concentrated density at two locations in spring and fall of 2008 and 2009. From the statistic analysis on plant characteristics and nutritional components, there were not many significant differences between GM and non-GM Chinese cabbage. Only few differences in the plant characteristics were found between the dense and normal planting. In the dense planting, there was no significant difference between GM and non-GM Chinese cabbages except for three out of 18 plant traits, such as leaf shape, hairiness and midrib length. On the other hand, nine plant traits including leaf length, leaf width, leaf color, leaf shape, fresh weigh of ground part, number of leaf, midrib length, midrib width and root diameter were slightly different between GM and non-GM Chinese cabbage in the normal planting. In case of leaf length, midrib length, midrib width and fresh weigh of ground part, there were significantly differences not only between two lines, but also between two locations. From nutritional component analysis, only five fatty acids were identified in the Chinese cabbage: palmitic acid, oleic acid, stearic acid, linoleic acid and linolenic acid. Except linoleic acid, four fatty acids in one gram of dried sample from GM line were little higher than those from non-GM line. However, there were no significant differences in total contents of fatty acids not only between GM and non-GM Chinese cabbage line, but also between northern and central cultivating areas in the normal and dense planting. According to the composition of inorganic elements identified in the samples from both lines, there were six macro-elements, such as N, P, Ca, K, Mg and Na, and four micro-elements, Cu, Fe, Mn and Zn. Based on the result from PCA analysis, specific clusters were not found between GM Chinese cabbage and the control line, but found between two regions.