• Applied Biological Chemistry
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• v.15 no.1
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• pp.27-33
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• 1972

The alkaline protease was isolated from the culture material of monascus sp. on wheat bran culture. The crude purification of this enzyme was extracted with distilled water and precipitated with ammonium sulfate of 0.5 saturation. And, the activity of this enzyme was determind very strongly by folin's colorimetric method. The optimal pH of this enzyme was ranging from pH 10 to 13 and the optimal temperature was $50^{\circ}C$. The pH stability was ranging from pH 5 to 12 and the enzyme activity was not inactivated by heat treatment in lower temperature than $40^{\circ}C$. The enzyme was protected from heat denature by the treatment of $Pb^#$, $Ba^#$, $Co^#$, $Zn^#$, and $Cu^#$, but was inactivated with $Hg^#$, $Fe^#$ strongly. Moreover, one of these metal ions, the cupper ion, has a strong protective activity on enzyme heat denature. And, it was not effected by treatment of EDTA.

• Korean Journal of Food Science and Technology
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• v.9 no.4
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• pp.291-294
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• 1977

Some chemical analysis of brewery's activated sludge were carried out in order to utilize it for animal feed. And results obtained were as follows. 1. Brewery's sludge, sun-dried for 3 days, contained 15.4% of water, 40.47 of crude protein, 4.02% of crude fiber, 13.3% crude ash and 19.4% nitrogen-free extract. 2. Total amino acid content of the brewery's sludge was 38% of its dry basis. The amounts, of all essential amino acids contained except tryptophan was enough for chicken growing and, especially, among the essential amino acids, the contents of leucine, isoleucine, phenylalanine, tyrosine, glycine and serine were two or three times as much as its need. 3. Other minerals contents except Magnesium and Cupper, were considerably low for animal feed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.4
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• pp.484-488
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• 1993

The heavy metal contents in Carassius auratus, that were sampled from Nov.1 to Nov. 31, 1991 at 6 areas in Joenlabuk-do. The mercury contents was determined by mercury analyzer using the combustion Goldamal-gamation method. The arsenic contents were determined by spectrophotometry using silver diethyl ditiho carbamate method. The contents of other heavy metals were determined by inductively coupled plasma spectrometer method. The levels of total mercury, arsenic, cadmium, lead, cupper, manganes, and zinc were determined and the results were summarized as follows : The 6 areas over all range(ppm) were Hg : 0.0167~0.0407, As : N.D.~0.0018, Cd : 0.1256~0.1935, Pb : 0.3536~0.6593, Cu : 0.2094~0.3792, Mn : 2.9059~6.9335, Zn : 14.3095~48.1615ppm. Among the seven heavy metals contents, the higest was zinc and the lowest was arsenic. The results show that contents of Hg As, Cd, Pb, Mn and Zn in Carassius auratus were lower than the FAO/WHO maximum allowance.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.799-811
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• 2019

The aim of this study was to evaluate heavy metal contamination and pollution index of agricultural soils around industrial complexes in the Jeon-Buk Regions of Korea. Soil samples near industrial complexes in 2017 were collected at two depths (0 - 15 and 15 - 30 cm) within a 500- and 1000-meter radius before planting. Eight heavy metals (Arsenic (As), cadmium (Cd), chromium (Cr), Cupper (Cu), nickel (Ni), lead (Pb), mercury (Hg) and zinc (Zn)) and the pollution index (PI), geoaccumulation index (Igeo) and soil pollution index (SPI) were evaluated based on soil contamination warning standard (SCWS). Overall, the heavy metal concentrations were below the SCWS. The PI ranged from 0.1 to 0.9 and categorized into Group 1 which is not polluted with any heavy metals. The average Igeo values of all the soil samples ranged from - 2.56 to 3.22. The Igeo values of Cd and Hg may not represent well the pollution index because the heavy metal concentrations in the soil is lower compared to the SCWS. In fact, based on the heavy metal concentrations, the Igeo for monitored soils should be categorized into Group 1, uncontaminated to moderately contaminated. However, the Igeo of Cd and Hg are classified into heavily contaminated. These results suggest that for calculating the Igeo, the heavy metal concentration and background concentration should be used very carefully if the heavy metal concentration in the soil is lower than the background concentration. SPI for all the soil samples ranged from 0.00 to 0.11 which indicates no heavy metal pollution was observed.

• Applied Biological Chemistry
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• v.32 no.1
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• pp.37-43
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• 1989

Some phenolics were examined as an antioxidant for the autoxidation of soybean oil. Soybean oil was autoxidized under a mild condition (the flow rate of 67ml $O_{2}/min$ and $50^{\circ}C$). The antioxidant effect was estimated by active oxygen method. Phenolics show distinctive antioxidant effect, and the effect is prominent when cupper or iron was added. Phenolics showed a tendency to increase antioxidant effect with an increase of the number of hydroxyl group, and the increasing order was ferulic acid, quinalizarin, sesamol, alizarin, fisetin and purpurogallin. However, the effect was remarkably low in ferulic acid, alizarin and quinalizarin. It was found that the antioxidant effect was dependent on the functional group and geometric molecular structure of phenolics.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.3
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• pp.191-198
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• 2014

Absorption and accumulation of heavy metals in plants were determined by phytoavailable contents rather than total contents of heavy metals. Therefore, phytoavailability-based management protocol should be prepared for safe food crop production in contaminated agricultural lands. This study was conducted to understand the distribution and phytoavailability of heavy metal in the Korean agricultural soils affected by abandoned mining sites along with investigation of soil properties (soil pH, OM, DOC, clay content, Al/Fe/Mn content) influencing on the metal phytoavailability. For this, 142 agricultural soils located nearby 39 abandoned mining sites distributed in five province in Korea, were analyzed. Among the four different heavy metals, cadmium (Cd) and zinc (Zn) appeared to exist in more phytoavailable form than cupper (Cu) and lead (Pb). Soil pH was the main factor governing phytoavailable Cd, Pb, and Zn showing positive relationship with partitioning coefficients of the corresponding metals; Cd (r = 0.66, P < 0.001), Pb (r = 0.70, P < 0.001), and Zn (r = 0.62, P < 0.001). This implied higher phytoavailability of the corresponding metals with higher soil pH. In contrast, phytoavailability of Cu (r = 0.41, p < 0.01) was only negatively related with soil DOC (dissolved organic carbon).

• Korean Journal of Environmental Agriculture
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• v.34 no.1
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• pp.21-29
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• 2015

BACKGROUND: Heavy metal adsorptionnot only depends on biochar characteristics but also on the nature of the metals involved and on their competitive behavior for biochar adsorption sites. The goal of this study was to investigate the competitive absorption characteristics of Cu and Cd in mono-metal and binary-metal forms by biochar derived from Phragmites communis. METHODS AND RESULTS: Batch and column experiments were conducted to evaluate the competitive adsorption characteristics of the biocharfor Cu and Cd. In the batch experiments, the maximum adsorption capacity of Cd(63 mg/g) by biochar was higher than that for Cu (55 mg/g) in the mono-metal adsorption isotherm. On the other hand, the maximum Cu adsorption capacity (40 mg/g) by biochar was higher than that for Cd(25 mg/g) in the binary-metal adsorption isotherm. Cu was the most retained cations. Cd could be easily exchanged and substituted by Cu. The amounts of adsorbed metals in the column experiments were in the order of Cd (121 mg/g) > Cu (96 mg/g) in mono-metal conditions, and Cu (72 mg/g) > Cd (29 mg/g) in binary-metal conditions. CONCLUSION: Overall, the results demonstrated that competitive adsorption among metals increased the mobility of these metals. Particularly, Cd in binary-metal conditions lost its adsorption capacity most significantly.

• Research in Plant Disease
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• v.11 no.1
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• pp.39-42
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• 2005

Powdery mildew, caused by Sphaerotheca aphanis var. aphanis, is an economically significant disease of strawberry in Korea. When powdery mildew is not controlled adequately, it often spreads rapidly through strawberry plants and damage is associated with reduced yields. Proper timing of fungicide applications is, therefore, essential for effective disease control. This study evaluated the efficacy by application schedule of fungicides before harvest stage for preventing powdery mildew in 2001-2003. The systemic fungicides, azoxystrobin, kresoxim-methyl, and cupper fungicide DBEDC were applied preventively during the first part of the cultivating season. Preventative applications of DBEDC by dipping treatment before transplanting and kresoxim-methyl by foliar spray before blooming stage were one of the most effective control schedule tested to prevent and manage this disease. This research demonstrated the significance of application time to control of powdery mildew, particularly provided elimination unnecessary sprays of agrochemicals and reduction costs for strawberry growers.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.5 no.1
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• pp.87-103
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• 1995

Since being granted permission for self-assessment of the work environment by the Department of Labor in 1992, POSCO's Industrial Hygiene Laboratory has participated in domestic and Foreign Quality Control Programs 8 times and has obtained remarkable results. It has made a lot of effort to be a proficient laboratory with the ability to observe and analyse environmental monitoring data. The summary of results is as follows: 1. POSCO's Industrial Hygiene Laboratory has received a "P(Proficient)" grade from the round 115 to round 119 of AIHA/NIOSH PAT Program for analysis of such metals as lead, cadmium, zinc, and chromium, and also has received a "P(Proficient)" grade from its round 119 of for organic solvent analysis, i,e,. Trichloroethylene(TCE), Carbon Tetr-achloride(CTC), 1,2-Dichloroethane(DCE), 1,1,1-Trichloroethane(MCM), Tetrachloroethylene (PCE), Chloroform(CFM), Benzene(BNZ), toluene(TOL), and O-xylene(OXY). 2. In the Quality Control Evaluation Program performed by the Industrial Health Research Institute,Korea Industrial Safety Corporation, POSCO has passed impressively in the3-metal analysis test for lead, cadmium, cupper, and in the 6 organic solvent analysis test for Benzene(BNZ), toluene(TOL), O-xylene(OXY), Trichloroethylene(TCE) and Methyl isobutyl keton(MIBK), n-Hexane with 2 standard deviations. These analytic techniques should be practically applied to various fields, and reliable results of environmental monitoring should be considered to improve the work environment and to keep workers from occupation related diseases.

• Journal of Soil and Groundwater Environment
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• v.28 no.6
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• pp.33-44
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• 2023

A risk assessment on the heavy metals including arsenic (As), cupper (Cu), lead (Pb), and zinc (Zn) was investigated by setting exposure routes in agricultural fields. Moreover, the factors requiring improvement in risk assessment were also discussed through a review of the dermal absorption slope factor (SF_abs) and total amount of suspended particles (TSP) in the current risk assessment guidelines. Assessment results show that the total cancer risk (TCR) of As through crop and soil ingestion was 1.51E-03 in adults and 6.37E-4 in children, which indicated a carcinogenic risk (exceeding 1E-05). On the other side, the harzard index (HI) was 3.37 in adults and 1.41 in children, which was evaluated as having a non-carcinogenic risk (>1). The carcinogenic purification targets for As were calculated to be 6.84 mg/kg in adults and 6.86 mg/kg in children, while the non-carcinogenic purification targets were calculated to be 13.43 mg/kg for adults and 22.54 mg/kg for children. When applying SF_abs 61 of the current guidelines, it appears that there is a carcinogenic risk even though the As exposure concentration is below the area of concern 1 standard (25 mg/kg), which suggestes that additional research on this factor is required for the risk assessment. In order to apply the measured suspended particle concentration to risk assessment, TSP should be derived from PM10 using an appropriate correlation equation. As a result, it is suggested to improve the risk assessment guidelines so that the mesured PM10 value measured in the field can be used directly.