• Korean Journal of Microbiology
• /
• v.41 no.3
• /
• pp.216-224
• /
• 2005

Chromatography has now been used successfully to provide the requisite purity for human plasma-derived biop-harmaceuticals such as coagulation factors and immunoglobulins. Recently, increasing attention has been focused on establishing efficient cleaning procedures to prevent potential contamination by microorganisms as well as carry-over contamination from batch to batch. The purpose of present study was to develop a cleaning validation system for the assurance of virus removal and/or inactivation during chromatography process. In order to establish an assay system for the validation of virus clearance during chromatography cleaning process, a quantitative real-time PCR method for porcine parvovirus(PPV) was developed, since PPV, a model virus for human parvovirus B19, has a high resistance to a range of physico-chemical treatment. Specific primers for amplification of PPV DNA was selected, and PPV DNA was quantified by use of SYBR Green I. The sensitivity of the assay was calculated to be 1.5 $TCID_{50}/ml$. The established real-time PCR assay was successfully applied to the validation of PPV removal and cleaning during SP-Sepharose cation chromatography for thrombin purification and Q-Sepharose anion chromatography for factor VIII purification. The comparative results obtained by real-time PCR assay and infectivity titrations suggested that the real-time PCR assay could be a useful method for chromatography cleaning validation and that it could have an additive effect on the interpretation and evaluation of virus clearance during the virus removal process.

• The Journal of the Petrological Society of Korea
• /
• v.9 no.2
• /
• pp.84-98
• /
• 2000

Daejeon-sa basalt in the Mt. Juwang area composed of 12 basalt flows alternate with 9 peperites and each basalt and peperite has the variety of thickness. Peperites yielded in Daejeon-sa basalt are mixed of basalt with reddish shale, of which textural type is globular peperite. Basalts yielded in Daejeon-sa basalt are massive basalt without vesicule, although sometimes vesicules are founded in upper within a flow unit. The basalt has mainly pseudomorph of olivine as phenocryst, and also plagioclase and clinopyroxene phenocryst. Matrix is mainly subophitic texture. The plotting result on the TAS diagram shows these basalts belong to the sub-alkaline, and it can be subdivided into calc-alkaline series on the basis of the diagram of Si02 vs. K20 and of alkali index vs. A1203 diagram. According to plots of wt.% oxides vs. wt.% MgO, abundances of A1203 and CaO increase with decreasing MgO while F ~ dOecre~ase . With decreasing MgO compatible elements decrease while incompatible elements increase. In spider diagram of MORB-normalized trace element patterns, HFS elements are nearly similiar with MORB, but LIL elements are enriched. Especially, contents of Ce, F: and Sm are enriched but Nb is depleted. In the chondrite-normalized REE patterns light REEs are enriched than heavy REEs. Tectomagmatic discrimination diagrams shows basalts in the study area are formed in the tectonomagmatic environment of subduction zone under continental margin. This result accord with characters of chemical composition mentioned above. Cr vs. Y diagram and CeM, vs. Ce diagram show that the primary magma of the basalts may formed by the about 15% partial melting of garnet-peridotite in the mantle wedge. After then, Daejeon-sa basalts may formed from evolved magma undergone mainly olivine fractional crystallization and contarnination of crustal materials before eruption.

• Korean Journal of Soil Science and Fertilizer
• /
• v.25 no.4
• /
• pp.325-333
• /
• 1992

An investigation was carried out to find out the effects of long-term application (14 and 28 years) of rice straw, compost and wheat straw on changes in soil chemical and physical properities, aspests of releasing potential nitrogen and nitrogen uptake by rice and maize from fine textured paddy soils with double cropping system in warm temperate area. The result obtained were summarized as follows : 1. The long-term application of organic matters improved plow layer and soil physical properties : bulk density and solid phase were decreased, while porosity and gaseous phase were decreased. 2. Average increment of total carbon per year was 0.0371% and 0.0407% for rice straw and compost, respectively, from 1 through 14 years ; it was 0.0007% and 0.0014% for the rice straw and compost, respectively, from 15 years through 28 years. The average increment of total notrogen per year was 0.0025% and 0.038% for the rice straw and compost, respectively, from 1 through 14 years ; 0.0014% and 0.0024% for the same treatments from 15 through 28 years. 3. $NH_4-N$ and amide-N were high in the soils with wheat straw application for 28 years ; the amino sugar-N in the soils with compost application for 28 years ; amino acid -N in the soils with rice straw application for 14 and 28 years ; and unidentified-N, in the control. 4. The released amount of available nitrogen with the submerged condition was higher at $30^{\circ}C$ than at $25^{\circ}C$ during the incubation. The amount of released available nitrogen at the field was aproximately same as that of $25^{\circ}C$ incubation. However, the released amounts from the incubation and the field were always lower than those extracted with reagents. 5. The amount of nitrogen uptake by rice and maize was highly correlated with available nitrogen extracted with phosphate buffer(pH 7.0). 6. The ratio of yield increase(milled rice) was 17, 12 and 7%, respectively, by application of rice straw, compost and wheat straw for 28 years, and 11% by application of rice straw for 14 years.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.6
• /
• pp.1120-1125
• /
• 2012

To assess fertilizer value of an quasi-aerobically fermented liquid clipped-grass fertilizer, aerobic incubation experiment using two texturally contrasting loam (L) and sandy loam (SL) soils was conducted for 60 days to investigate temporal variations in N mineralization pattern of the liquid fertilizer applied. To do so, the quasi-aerobically fermented liquid clipped-grass fertilizer was prepared, applied to each soil at a rate of 200 kg-N $ha^{-1}$ and aerobically $25^{\circ}C$ in the dark. During incubation, soil water content was adjusted to field moisture capacity (-33 kPa of soil matric potential) by adding distilled water as necessary to maintain their initial weights. At desired time of incubation (0, 1, 5, 10, 20, 40, and 60 days after incubation), soil was sampled and analyzed for inorganic nitrogen ($NH_4{^+}$-N and $NO_3{^-}$-N) concentrations, pH, EC, total carbon contents and total nitrogen contents. Concentrations of $NH_4{^+}$-N began to decrease right after incubation for L soils, and 10 days after incubation for SL soils, while those of $NO_3{^-}$-N began to increase onset of $NH_4{^+}$-N disappearance. The results of this study showed that quasi-aerobically fermented liquid clipped-grass fertilizer could serve as an alternative to chemical N fertilizer.

• 한국유가공학회:학술대회논문집
• /
• 2002.04a
• /
• pp.59-60
• /
• 2002

Edible films such as wax coatings, sugar and chocolate covers, and sausage casings, have been used in food applications for years$^{(1)}$ However, interest in edible films and biodegradable polymers has been renewed due to concerns about the environment, a need to reduce the quantity of disposable packaging, and demand by the consumer for higher quality food products. Edible films can function as secondary packaging materials to enhance food quality and reduce the amount of traditional packaging needed. For example, edible films can serve to enhance food quality by acting as moisture and gas barriers, thus, providing protection to a food product after the primary packaging is opened. Edible films are not meant to replace synthetic packaging materials; instead, they provide the potential as food packagings where traditional synthetic or biodegradable plastics cannot function. For instance, edible films can be used as convenient soluble pouches containing single-servings for products such as instant noodles and soup/seasoning combination. In the food industry, they can be used as ingredient delivery systems for delivering pre-measured ingredients during processing. Edible films also can provide the food processors with a variety of new opportunities for product development and processing. Depends on materials of edible films, they also can be sources of nutritional supplements. Especially, whey proteins have excellent amino acid balance while some edible films resources lack adequate amount of certain amino acids, for example, soy protein is low in methionine and wheat flour is low in lysine$^{(2)}$. Whey proteins have a surplus of the essential amino acid lysine, threonine, methionine and isoleucine. Thus, the idea of using whey protein-based films to individually pack cereal products, which often deficient in these amino acids, become very attractive$^{(3)}$. Whey is a by-product of cheese manufacturing and much of annual production is not utilized$^{(4)}$. Development of edible films from whey protein is one of the ways to recover whey from dairy industry waste. Whey proteins as raw materials of film production can be obtained at inexpensive cost. I hypothesize that it is possible to make whey protein-based edible films with improved moisture barrier properties without significantly altering other properties by producing whey protein/lipid emulsion films and these films will be suitable far food applications. The fellowing are the specific otjectives of this research: 1. Develop whey protein/lipid emulsion edible films and determine their microstructures, barrier (moisture and oxygen) and mechanical (tensile strength and elongation) properties. 2. Study the nature of interactions involved in the formation and stability of the films. 3. Investigate thermal properties, heat sealability, and sealing properties of the films. 4. Demonstrate suitability of their application in foods as packaging materials. Methodologies were developed to produce edible films from whey protein isolate (WPI) and concentrate (WPC), and film-forming procedure was optimized. Lipids, butter fat (BF) and candelilla wax (CW), were added into film-forming solutions to produce whey protein/lipid emulsion edible films. Significant reduction in water vapor and oxygen permeabilities of the films could be achieved upon addition of BF and CW. Mechanical properties were also influenced by the lipid type. Microstructures of the films accounted for the differences in their barrier and mechanical properties. Studies with bond-dissociating agents indicated that disulfide and hydrogen bonds, cooperatively, were the primary forces involved in the formation and stability of whey protein/lipid emulsion films. Contribution of hydrophobic interactions was secondary. Thermal properties of the films were studied using differential scanning calorimetry, and the results were used to optimize heat-sealing conditions for the films. Electron spectroscopy for chemical analysis (ESCA) was used to study the nature of the interfacial interaction of sealed films. All films were heat sealable and showed good seal strengths while the plasticizer type influenced optimum heat-sealing temperatures of the films, 130$^{\circ}$C for sorbitol-plasticized WPI films and 110$^{\circ}$C for glycerol-plasticized WPI films. ESCA spectra showed that the main interactions responsible for the heat-sealed joint of whey protein-based edible films were hydrogen bonds and covalent bonds involving C-0-H and N-C components. Finally, solubility in water, moisture contents, moisture sorption isotherms and sensory attributes (using a trained sensory panel) of the films were determined. Solubility was influenced primarily by the plasticizer in the films, and the higher the plasticizer content, the greater was the solubility of the films in water. Moisture contents of the films showed a strong relationship with moisture sorption isotherm properties of the films. Lower moisture content of the films resulted in lower equilibrium moisture contents at all aw levels. Sensory evaluation of the films revealed that no distinctive odor existed in WPI films. All films tested showed slight sweetness and adhesiveness. Films with lipids were scored as being opaque while films without lipids were scored to be clear. Whey protein/lipid emulsion edible films may be suitable for packaging of powder mix and should be suitable for packaging of non-hygroscopic foods$^{(5,6,7,8,)}$.

• Journal of Food Hygiene and Safety
• /
• v.32 no.1
• /
• pp.20-26
• /
• 2017

Foodborne disease outbreaks associated with produces have been increasing in occurrence worldwide. This study investigated microbial contamination levels on thirteen kinds of agricultural products from farms stage to evaluate potential hazards associated with foodborne illness. A total of 1,820 samples were collected in major cultivating area from 2013 through 2015, and analyzed to enumerate aerobic bacterial counts, coliforms/E. coli, Bacillus cereus and Staphylococcus aureus. In addition, the prevalence study for four kinds of microorganisms (Escherichia coli, E. coli O157:H7, Salmonella spp. and Listeria monocytogenes) was performed on each sample. Aerobic bacterial counts ranged from 0.01 to 7.18 log CFU/g, with the highest bacterial cell counts recorded for watermelon. Coliforms were detected in 651 samples (35.8%) with a minimum of 0.01 log CFU/g and a maximum of more than 5 log CFU/g. B. cereus was detected in 169 samples (9.3%) ranging from < 0.01 to 2.48 log CFU/g among total samples analyzed. S. aureus was detected in 14 samples (0.7%) with a minimum of 0.01 log CFU/g and a maximum of 1.69 log CFU/g. E. coli was detected in 101 samples (5.5%) among 1,820 samples. E. coli O157:H7, Salmonella spp. and L. monocytogenes were not detected in any of the samples. The microbial contamination levels of several agricultural products determined in this study may be used as the fundamental data for microbiological risk assessment (MRA).

• Journal of Korean Society of Environmental Engineers
• /
• v.30 no.9
• /
• pp.961-972
• /
• 2008

In 2004, total emissions of Greenhouse Gases(GHGs) in Korea was estimated to be about 590 million metric tons, which is the world's 10th largest emissions. Considering the much amount of nation's GHG emissions and growing nation's position in the world, GHG emissions in Korea should be reduced in near future. The CO$_2$ emissions from two sub-sections of energy sector in Korea, such as thermal power plant and industry section(including manufacturing and construction industries), was about 300 million metric tons in 2004 and this is 53.3% of total GHG emissions in Korea. So, the mitigation of CO$_2$ emissions in these two section is more important and more effective to reduce the nation's total GHGs than any other fields. In addition, these two section have high potential to qualitatively and effectively apply the CCS(Carbon Capture and Storage) technologies due to the nature of their process. There are several CCS technologies applied to these two section. In short term, the chemical absorption technology using amine as a absorbent could be the most effectively used. In middle or long term, pre-combustion technology equipped with ATR(Autothermal reforming), or MSR-$H_2$(Methane steam reformer with hydrogen separation membrane reactor) unit and oxyfuel combustion such as SOFC+GT(Solid oxide fuel cell-Gas turbine) process would be the promising technologies to reduce the CO$_2$ emissions in two areas. It is expected that these advanced CCS technologies can reduce the CO$_2$ avoidance cost to $US 8.5-43.5/tCO$_2$. Using the CCS technologies, if the CO$_2$ emissions from two sub-sections of energy sector could be reduced to even 10% of total emissions, the amount of 30 million metric tons of CO$_2$ could be mitigated.

• Journal of Applied Biological Chemistry
• /
• v.52 no.4
• /
• pp.180-186
• /
• 2009

Whole plants of Vitex rotundifolia were extracted for 2 days with methylene chloride ($CH_2Cl_2$) followed by extraction of the residue for an additional 2 days. The same procedure was also applied using methanol (MeOH). The two crude extracts were combined and partitioned between $CH_2Cl_2$ and $H_2O$. The organic layer was further partitioned between n-hexane and 85% aq. MeOH, and the aqueous layer was also further fractionated with n-BuOH and $H_2O$, successively. From the 85% aq. MeOH fraction, one compound was isolated through the repeated HPLC. According to the results of physicochemical data including NMR and MS, the chemical structure of the compound was determined as artemetin (1). The antiproliferative effects of the crude extracts, fractions, and compound against HT1080, AGS, MCF-7 and HT-29 human cancer cells were compared with the control by using MTT assay. In the comparative analysis, the 85% aq. MeOH fraction exhibited the strongest antiproliferative effects on human cancer cell lines in a dose-dependent manner (p<0.05). In addition, exposure of compound 1 isolated from 85% aq. MeOH fraction led to strong antiproliferative effect in HT1080 cancer cell lines. These results suggest that the extracts and compound isolated from V. rotundifolia may be used as potential chemopreventive and chemotherapeutic agents.

• Journal of Animal Science and Technology
• /
• v.49 no.2
• /
• pp.269-278
• /
• 2007

This study was performed to measure the pH, proximate composition, physicochemical properties, changes of protein bands, Hunter color values and endpoint cooking temperature of chicken leg and breast muscles during cooking from 64 to 74℃ with 2℃ increments. Chicken leg had higher pH, moisture and fat contents (%) and lower protein solubility(P<0.05) than chicken breast. Although the cooking losses(CLs, %) of chicken muscles increased with increased cooking temperature, the addition of 2% salt did not affect CL. The redness values of chicken leg without 2% salt were higher than chicken breast, however, the addition of 2% salt reduced the differences of the redness. Protein solubility decreased with increased cooking temperatures and were not affected by the addition of salt, and no further changes were observed higher than 68℃. Protein bands having the molecular weights of 66 and 54kDa were disappeared in the chicken leg at the cooking temperatures of 66～70℃, whereas 66, 54 and 34kDa in the chicken breast. These protein bands could be used potential indicators to determine the endpoint cooking temperature in chicken muscles.

• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.11
• /
• pp.1007-1018
• /
• 2009

Hydrocyclone is widely used in industry, because of its simplicity in design, high capacity, low maintenance and operational cost. The separation action of a hydrocyclone treating particulate slurry is a consequence of the swirling flow that produces a centrifugal force on the fluid and suspended particles. In spite of hydrocyclone have many advantage, the application for treatment of urban stormwater case study were rare. We conducted a laboratory scale study on treatable potential of micro particles using hydrocyclone filter (HCF) that was a combined modified hydrocyclone with perlite filter cartridge. Since it was not easy to use actual storm water in the scaled-down hydraulic model investigations, it was necessary to reproduce ranges of particles sizes with synthetic materials. The synthesized storm runoff was made with water and addition of particles; ion exchange resin, road sediment, commercial area manhole sediment, and silica gel particles. Experimental studies have been carried out about the particle separation performance of HCF-open system and HCF-closed system. The principal structural differences of these HCFs are underflow zone structure and vortex finder. HCF was made of acryl resin with 120 mm of diameter hydrocyclone and 250 mm of diameter filter chamber and overall height of 800 mm. To determine the removal efficiency for various influent concentrations of suspended solids (SS) and chemical oxygen demand (COD), tests were performed with different operational conditions. The operated maximum of surface loading rate was about 700 $m^3/m^2$/day for HCF-open system, and 1,200 $m^3/m^2$/day for HCF-closed system. It was found that particle removal efficiency for the HCF-closed system is better than the HCF-open system under same surface loading rate. Results showed that SS removal efficiency with the HCF-closed system improved by about 8~20% compared with HCF-open system. The average removal efficiency difference for HCF-closed system between measurement and CFD particle tracking simulation was about 4%.