• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.161-167
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• 2015

BACKGROUND: For the heavy metal cotamination sites, it is very important to estimate the human bioavailability quotients for heavy metals in paddy soils released from mine tailings, which is a major source of contamination in Korea, and to assess the human health risks of heavy metals. METHODS AND RESULTS: This experiment was carried out to investigate the human bioavailability quotient of the heavy metals in paddy soils below part of the closed metalliferous mine. For estimating the human bioavailability quotients for heavy metals, 30 paddy soils below part of the closed mine were collected, and analyzed for Cd, Cu, Pb, Zn, and As using simple bioavailability extraction test(SBET). The quantities of Cd, Cu, Pb, Zn and As extracted from paddy soils below part of the mine by using the SBET analysis were 28.1, 17.3, 34.1, 14.6 and 2.3% respectively. Specially, the maximum values of Cd, Pb and Zn were 73.3, 81.5 and 58.1% of human bioavailability quotient, respectively, and varied considerably among the sampling sites. The human bioavailability quotient of Cd, Cu, Pb and Zn in soils near the closed mine showed significant positive correlation among soil pH value, O.M. and Ex. Ca. contents, while it correlated negatively between soil Ex. K and Ex. Mg contents in paddy soils. Also, its of Cd, Cu, Pb and Zn in paddy soils showed significant positive correlation with 0.1M HCl extractable and total contents, while in soils, it correlated negatively with As content in soil near the closed mine. CONCLUSION: The results of the simple bioavailability extraction test (SBET) indicate that regular ingestion of soils by the local population could be closed a potential health threat due to long-term heavy metals exposure in these mine areas.

• 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 %.

• Restorative Dentistry and Endodontics
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• v.35 no.2
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• pp.80-87
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• 2010

The purpose of this study was to compare the different canal irrigation methods to prevent the formation of precipitate between sodium hypochlorite (NaOCl) and chlorhexidine (CHX). Extracted 50 human single-rooted teeth were used. The root canals were instrumented using NiTi rotary file (Profile .04/#40) with 2.5% NaOCl and 17% EDTA as irrigants. Teeth were randomly divided into four experimental groups and one control group as follows; Control group: 2.5% NaOCl only, Group 1: 2.5% NaOCl + 2% CHX, Group 2: 2.5% NaOCl + paper points + 2% CHX, Group 3: 2.5% NaOCl + preparation with one large sized-file + 2% CHX, Group 4: 2.5% NaOCl +95% alcohol+ 2% CHX. The teeth were split in bucco-lingual aspect and the specimens were observed using Field Emission Scanning Electron Microscope. The percentages of remaining debris and patent dentinal tubules were determined. Statistical analysis was performed with one-way analysis of variance (ANOVA). Energy Dispersive x-ray Spectroscopy was used for analyzing the occluded materials in dentinal tubule for elementary analysis. There were no significant differences in percentage of remaining debris and patent tubules between all experimental groups at all levels (p > .05). In elementary analysis, the most occluded materials in dentinal tubule were dentin debris. NaOCl/CHX precipitate was detected in one tooth specimen of Group 1. In conclusion, there were no significant precipitate on root canal, but suspected material was detected on Group 1. The irrigation system used in this study could be prevent the precipitate formation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.4
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• pp.465-471
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• 2008

Physicochemical characteristics of black garlic were analyzed. Colorimetry measurement showed that the black garlic, compared with fresh and steamed garlics, was the highest in a value and the lowest in L and b values. Crude lipid, crude protein, and total sugars were the highest in black garlic, which was followed by steamed and fresh garlic. On the other hand, moisture content was the lowest in the black garlic and the highest in the fresh garlic. The pH of garlics was ca. 6.8, 6.5, and 4.4 in fresh, steamed, and black garlic, respectively, which indicated that garlics tended to be acidified with the thermal processing. Total pyruvate and total thiosulfinates were the lowest in steamed garlic ($77{\mu}mol$/g and 0.07 OD/g for each) and the highest in black garlic ($278{\mu}mol$/g and 0.77 OD/g). Arabinose and galactose were detected only in black garlic and their contents were 1.6 and 13 mg/100 g, respectively. Free sugars such as glucose, sucrose and fructose were the highest in the order of fresh, steamed, and black garlic. Potassium was a predominant mineral in all garlics, constituting 76% of total minerals. Glutamic acid, arginine, and aspartic acid were the major composition amino acids in all garlics, regardless of processing conditions. 15 kinds of free amino acids were detected in fresh and steamed garlic, while five more free amino acids, O-phosphoethanolamine, and urea were additionally detected in black garlic.

• Korean journal of food and cookery science
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• v.4 no.2
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• pp.31-38
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• 1988

The chicken cooked by three different methods were put and sensory evaluation, mechanical and chemical composition test. The results were as following : 1. Standard recipe were as followig : \circled1 Kettle cooking was chicken 700 g, waxyrice 100 g, garlic 30 g, water 2000 cc, time 60 min. \circled3 Pressure cooking was chicken 700 g, waxyrice 100 g, garlic 30 g, water 2000 cc, time 30 min. \circled3 Microwave cooking was chicken 700g, waxyrice 100 g, garlic 30 g, water 1000 cc, time 30 min. 2. Sensory evaluation \circled1 There were no typical difference of the color of soupstock with in the three cooking methods. \circled2 The turbidity of soupstock was from Kettle cooking, microwave cooking and pressure cooking in turn. \circled3 There were no typical difference of the viscosity of soupstock with in the three cooking methods. \circled4 The kettle cooking was the best of mouthfeel and taste. \circled5 There were no typical difference of muscle, with in the three cooking methods. 3. Mechanical Test \circled1 The result of the cutting force of muscle which measured by rheomether were the leg muscle was more tough than breast muscle. \circled2 The viscosity of boiled rice was from kettle cooking, pressure cjooking and microwave cooking in turn. \circled3 The result of the turbidity of soupstock which measured by spectrophotmeter was from kettle cooking, pressure cooking and microwave cooking in turn. 4. Proximate chemical composition \circled1 Protein of muscle was 20.30-25.67%, Soupstock was 0.29-0.72% \circled2 Fat of muscle was 27.29-47.15% , Soupstock was 37-68.38%. \circled3 Potasium of muscle was 2.75-3.6 mg, Soupstock was 1.15-6.3 mg. \circled4 Iron of muscle was 1.17-1.39 mg, Soupstock was 0.96 mg.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.121-127
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• 2006

Microbial and nutritional characteristics of Kwangchun shrimp Jeotgal (salt-fermented shrimp) were assessed. Total mesophilic bacteria, coliforms, and S. aureus counts in Kwangchun shrimp Jeotgal were 3.48-5.42, 2.22-2.95, and 0.58-2.51 $log_{10}CFU/g$, respectively. Yeast and mold were detected only in Ohjeot (1.99 $log_{10}CFU/g$) and Yookjeot (1.47 $log_{10}CFU/g$). B. cereus, L. monocytogenes, Vibrio spp. and E. coli were not detected in Kwangchun shrimp Jeotgal, which contained abundant macrominerals (Ca, Mg, Na, K), with Na showing highest content. Palmitic acid content was higher than those of other saturated fatty acids. Eicosapentaenoic acid and docosahexaenoic acid contents were higher than those of other poly unsaturated fatty acids. Results showed Kwangchun shrimp Jeotgal is safe microbiologically with abundant nutritional components.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1135-1141
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• 2000

For investigation of new utilization as jang-products, Meju was prepared using barely bran. As barley meju was fermented, change of pH was $5.2{\sim}5.6$, it was indistinguishable change. L-value of color was changed from 46.9 to 60.3, that meant it was getting moe dark. The counts of aerobic bacteria were $4.8{\times}10^7{\sim}5.6{\times}10^9$ CFU/g, it was extraordinarily increased during fermentation. Counts of Yeast, molds, and bacteria were $9.1{\times}10^6{\sim}5.0{\times}10^8$ CFU/g, $8.3{\times}10^5{\sim}6.9{\times}10^7$, and $2.0{\times}10^2{\sim}4.5{\times}10^6$ CFU/g, respectively. Crude ash content was $3146.0{\sim}7147.4$ mg%. The level of K was the highest in quantity among the crude ash in barely meju. 7 free sugars(i.e., raffnose, stachyose, inositol, fructose, glucose, arabinose, and maltose), 3 volatile organic acid(i.e., acetic acid, propionic acid, and butyric acid) and 4 non-volatile organic acid(i.e., fumaric acid, ${\alpha}-ketoglutaric$ acid, malic acid, and citric acid) were detected. The content of free amino acid was $596.3{\sim}1580.8$ mg%. Glutamic acid was most abundant component among the amino acids, 2nd abundant component was alanine, it's content was $79.9{\sim}165.3$ mg%, 3rd abundant component was leucine, it's count was $41.7{\sim}161.6$ mg%. Finally, essential amino acid content was revealed $33.2{\sim}40.38%$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.787-795
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• 2001

For the developing natural fisheries flavoring substances using crustacea, the flavor constituents of enzyme hydrolysates from shore swimming crab (crab) and spotted shrimp (shrimp) were investigated. In taste-active compounds of both enzyme hydrolysates, total free amino acid contents of crab and shrimp enzyme hydrolysates were 5,226.7 mg% and 8,757.3 mg%, respectively. The major amino acids were taurine, glutamic acid, proline, asparagine, glycine, alanine, valine, leucine, lysine anserine and arginine. As for ATP related compounds, AMP was the principal component and small amounts of IMP was detected in both enzyme hydrolysates. In the quarternary ammonium bases, betaine was the principal component (593.8mg%), and contents of TMAO and betaine in both samples were 60.7 mg% and 850.0 mg%, 124.1 mg% and 755.9 mg%, respectively. The major components were Na, K, P and Cl in inorganic ions. The major fatty acids of both sample were 14 : 0, 16 : 0, 16 : 1n7, 18 : 1n9, 20 : 5n3 and 22 : 6n3, and composition ration of n3 polyunsaturated fatty acids of were 27.8% and 28.5%, respectively. Total 99~109 volatile compounds were detected as a cooked odor of crab and shrimp enzyme hydrolysates by SDE apparatus/gas chromatography/mass spectrometry. The volatile flavor compounds identified from cooked crab enzyme hydrolysate were composed of 6 acids, 10 alcohols, 7 aldehydes, 11 ketones, 1 ester, 5 phenols, 4 benzenes, 22 hydrocarbons, 1 furan, 21 nitrogen containing compounds and 11 micellaneous compounds. And the volatile flavor compounds indentified from cooked shrimp enzyme hydrolysate were composed of 13 acids, 10 alcohols, 6 aldehydes, 10 ketones, 3 esters, 2 phenols, 5 benzenes, 36 hydrocarbons, 1 furan, 14 nitrogen containing compounds and 8 micellaneous compounds.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.1
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• pp.45-52
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• 1989

The effects of soil properties and N, P and K application rates on the contents of inorganic constituents in the rhizomas of Ji-whang were investigated to know the condition for producing the better quality rhizoma of Ji-whang. Most of soil texture for Ji-whang cultivating belongs to sandy clay loam and sandy loam soils. The nitrogen contents in the rhizomas of Ji-whang was negatively correlated with the contents of organic matter and total nitrogen in surface soils, whereas positively correlated with the sand contents in subsoils. The calcium contents in the rhizomas of Ji-whang were negatively correlated with the sand contents, however, positively correlated with the contents of clay and organic matter in soils. The iron contents was positively correlated with the contents of clay, available phosphorus and exchangeable potassium in surface soils. Much more contents of the inorganic constituents in the leaf of Ji-whang was generally detected than that in the rhizoma of Ji-whang. The contents of iron and copper in the leaf was determined to be more than that in the rhizomas by ten times. In the results of field experiments, it is apparent that the nitrogen contents in the rhizoma and leaf increased with increasing N application rate more than 20kg/10a and 10kg/10a, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1130-1136
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• 2011

This study was carried out to determine the effects of pig slurry on growth of potato (Solanum tuberosum L. cv. Dejima), soil chemistry properties and infiltration water quality in volcanic ash soil and non-volcanic ash soil of Jeju. Fertilization of liquid pig manure was based on nitrogen. In volcanic ash soil and non-volcanic ash soil, there was no difference in the height and diameter of stems in chemical fertilizer and liquid pig manure application treatments. Also yields of potatoes were no significantly difference in chemical fertilizer and liquid pig manure application treatments. pH in all soil was increased by application of liquid pig manure compared to the chemical fertilizer plot. Contents of exchangeable K in all soil were accumulated excessively by fertilization of pig manure 100% compared to the chemical fertilizer 100%. But there was no difference between the chemical fertilizer 50%+liquid pig manure 50% and chemical fertilizer 100%. No difference between the chemical fertilizer and liquid pig manure was observed in available phosphate, exchangeable Ca and Mg. $NO_3$-N concentration of infiltration water sample collected at 70cm of soil depth was lower non-fertilizer than chemical fertilizer and liquid pig manure application treatments. In volcanic ash soil, the $NO_3$-N concentration of infiltration water was decreased from early, except liquid manure 100%. In non volcanic ash soil, the $NO_3$-N concentration of infiltration water increased until October 8, but then was reduced. In all soils, $NO_3$-N concentration of infiltration water was higher in the liquid manure 100% than those in the chemical fertilizer 100% and chemical fertilizer 50%+liquid pig manure 50%, but there were no differences. In conclusion, the growth of potato, fertilization of soil and $NO_3$-N content of infiltration water were not different between chemical 50%+liquid pig manure 50% and chemical 100% plot. So, liquid pig manure could be substituted for some amount of chemical fertilizer.