• Journal of Korean Society on Water Environment
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• v.35 no.6
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• pp.510-519
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• 2019

The 'Stable Isotope Analysis in R' (SIAR), one of the Bayesian mixing models for stable isotopes, has been proven to be useful for source apportionment of nitrates in rivers. In this study, the contribution ratios of nitrate sources were quantified by using the SIAR based on nitrogen and oxygen stable isotope measurements in the Yeongsan River. From the measurements, it was found that the values of δ¹⁵N-NO₃ and δ¹⁸O-NO₃ ranged from -8.2 ‰ to +13.4 ‰ and from +2.2 ‰ to +9.8 ‰, respectively. We further analyzed the contribution ratios of the five nitrate sources by using the SIAR. From the modeling results, the main nitrate source was found to be soil N (29.3 %), followed by sewage (26.7 %), manure (19.6 %), chemical fertilizer (17.9 %) and precipitation (6.3 %). From the results, it was found that the anthropogenic sources, i.e., sewage, manure and chemical fertilizer contribute 64.2% of the total nitrate inflow from the watershed. Due to the significant correlation of δ¹⁵N-NO₃ and lnNO₃^- in this study, the fractionation factors reflecting the biogeochemical processes of stable isotope ratios could be directly obtained. This may make the contribution ratios obtained in this study more precise. The fractionation factors were identified as +3.64 ± 0.91 ‰ for δ¹⁵N-NO₃ (p<0.01) and -5.67 ± 1.73 ‰ for δ¹⁸O-NO₃(p<0.01), respectively, and were applied in using the SIAR. The study showed that the stable isotope method using the SIAR could be applied to quantitatively calculate the contribution ratios of nitrate sources in the Yeongsan River.

• Development and Reproduction
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• v.4 no.2
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• pp.237-242
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• 2000

Growth hormone releasing hormone (GHRH), the major hypothalamic stimulus of GH secretion from the anterior pituitary gland, has been found to be present in several extrahypothalamic sites including placenta testis, ovary and anterior pituitary gland. The present study was performed to elucidate the role of pituitary GHRH on proliferation of cells derived from rat anterior pituitary gland. The GHRH content of pituitary tissue, cultured pituitary cells, and the conditioned media was evaluated by radioimmunoassay (RIA). Primary cultures of pituitary cells derived from adult rats were prepared by enzymatic dispersion. Significant amounts of GHRH-like molecules were detected in both pituitary tissue and cell cultures by GHRH RIA. Competition curves with increasing amounts of tissue extracts and conditioned media were parallel with those of standard peptide, indicating that the pituitary GHRH-like material is similar to authentic GHRH. To analyze specific cell types responsible for producing GHRH in anteroior pituitary, cell fractionation technique combined with GHRH RIA was performed. In cell fractionation experiment, the highest level of GHRH content was found in gonadotrope enriched-fraction and followed by somatotrope-, lactotrope- and thyrotrope-fraction. Treatment of pituitary cells with GHRH resulted in a dose-dependent increase in [$^3$H] thymidine incorporation. The mitogenic effect of GHRH could be mediated by typical oncogenic activation since the GHRH induced transient increase in c-fos mRNA levels with peak response at 30 minutes. The present study demonstrated that i) the pituitary GHRH expressed in the rat anterior pituitary gland can be secreted, ii) among the various cell types, gonadotropes and somatotorpes are the major GHRH source, and iii) the GHRH treatment increased the [$^3$H] thymidine incorporation and c-fos transcriptional activity in the pituitary cell culture. These findings suggested that GHRH could participated in the paracrine and/or autocrine regulation of cell proliferation, as well as promoting growth hormone secretion.

• Analytical Science and Technology
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• v.26 no.4
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• pp.262-267
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• 2013

Gravitational field-flow fractionation (GrFFF) is a separation technique that utilizes earth's gravity as the external field. GrFFF is a convenient tool for the size and/or density-based separation of micron-sized particles of various origins. In this study, GrFFF was employed for size-based separation of oyster mushroom spores. Oyster mushroom spores have smooth surface and are of cylindrical to narrow kidney-shapes with 5 to 12 im in longer dimension and 3 to 4 im in shorter dimension, as was confirmed by optical microscope (OM). GrFFF conditions were optimized for separation and characterization of spores by varying the channel flow rate from 0.5 to 1 mL/min. During the GrFFF elution of the spores, 3 fractions were collected to confirm the growth of oyster mushroom spore. The collected fractions were incubated for 30 days in water to examine the influence of the size on the growth of the spores. Results suggested that the oyster mushroom spores collected at the middle part of the GrFFF fractogram grew faster than those collected at the beginning or at the end of the fractogram.

• Korean Journal of Food Science and Technology
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• v.24 no.1
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• pp.1-6
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• 1992

Changes in protein distributiun, eletrophoretic patterns and amino acid composition were investigated during germination of malting barley. Fractionation of the protein complex in ungerminated malting barley resulted in a higher hordein fraction but less glutelin fraction of the protein complex in ungerminated malting barley resulted in a higher hordein fraction but less glutelin fraction as compared to germinated malting barley. As germination proceeded, NPN, globulin and glutelin fractions continued to increase, accmpanied by decreases in albumin and hordein fractions. The electrophoretic pattern of malting barley proteins showed three bands (molecular weight range of $15,000{\sim}41,000$ daltons) in albumin fraction, five bands ($19,000{\sim}61,000$ daltons) in globulin fraction, five bands ($18,000{\sim}56,000$ daltons) in hordein fraction and tour bands ($20,000{\sim}47,000$ daltons) in glutelin fraction, exhibiting quantitative changes in each fraction during germination. Amino acid analysis showed that glutamic acid, histidine, aspartic acid, serine, glycine, valine, alanine and leucine were major amino acids of proteins in malting barley grains. Glutamic acid increased slightly, but other amino acids showed no definite trend as germination proceeded.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.96-104
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• 2017

To obtain the immunomodulating polysaccharide from chaga mushroom (Inonotus obliquus sclerotia, IO), crude polysac- charide fractions (IO-M-CP and IO-CP, respectively) prepared from hot-water extract (IO-W) of I. obliquus by EtOH precipitation after MeOH reflux or not. After IO-W was re-dissolved in water followed by EtOH addition in the case without MeOH reflux, EtOH mixture was fractionated into EtOH-soluble (IO-E) and crude polysaccharide (IO-CP). In the meanwhile, MeOH-soluble fraction (IO-M) was separated from IO-W after MeOH reflux. The residue was dissolved in water and was added by EtOH, and then EtOH mixture was also fractionation into EtOH-soluble (IO-M-E) and crude polysaccharide (IO-M-CP). As a result of the macrophage stimulating activity of these fractions, IO-CP and IO-M-CP showed significantly increased cell proliferation and cytokines production than IO-W. Particularly, IO-M-CP promotes the production of IL-12 more than IO-CP. In the splenocytes proliferating activity and intestinal immune system modulating activity through Peyer's patch, both of 2 crude polysaccharide fractions were significantly promoted in cell proliferation and cytokines production than IO-W, and IO-M-CP was more potent than IO-CP in IL-2 production from splenocytes and GM-CSF production ($10{\mu}g/mL$) in Peyer's patch cells. In addition, immunomodulating polysaccharide fractions (IO-M-CP and IO-CP) prepared from IO-W by EtOH precipitation with or without EtOH reflux showed no significant difference in the chemical composition and component sugar. These results suggested that MeOH reflux might exclude low-molecular weight materials from IO-W and consequently increase the immunomodulating activity of IO-M-CP. Therefore, it was confirmed that immunomodulation of polysaccharide prepared from hot-water extract of chaga mushroom was enhanced by fractionation including MeOH reflux and EtOH precipitation.

• Analytical Science and Technology
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• v.12 no.4
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• pp.284-289
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• 1999

Dissolved inorganic carbonates in ground water were quantitatively recovered by using gas evolution method. Gas evolution method was found to be less time-consuming, less susceptible to the contamination fromatmospheric $CO_2$ and little affected by the sulfate ions in comparison to the direct precipitation method. Extraction efficiency of nearly 99% could be achieved by gas evolution method in two hours using recirculated gas at a sweeping rate of 4 liter per minute. Samples for carbon isotope fractionation study were collected in three fractions with collection times. The evolution time for the first fraction was one hours, and then second and third fractions were collected at intervals of 30 minutes, respectively. A small portion of each fraction was analyzed to evaluate ${\delta}^{13}C$ values, which were measured to be -7.9‰, -3.0‰ and +0,4‰ for the each fraction. The result clearly indicated that gas evolution method generates isotopically lighter carbon at the beginning of the purging process and heavier isotopes at the end. However, this isotope fractionation effect could be neglected by the almost complete recovery of carbonates.

• Analytical Science and Technology
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• v.28 no.1
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• pp.33-39
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• 2015

CdS-QD particles are a nano-sized semiconducting crystal that emits light. Their optical properties show great potential in many areas of applications such as disease-diagnostic reagents, optical technologies, media industries and solar cells. The wavelength of emitting light depends on the particle size and thus the quality control of CdS-QD particle requires accurate determination of the size distribution. In this study, CdS-QD particles were synthesized by a simple ${\gamma}$-ray irradiation method. As a particle stabilizer polyvinyl pyrrolidone (PVP) were added. In order to determine the size and size distribution of the CdS-QD particles, sedimentation field-flow fractionation (SdFFF) was employed. Effects of carious parameters including the the flow rate, external field strength, and field programming conditions were investigated to optimize SdFFF for analysis of CdS-QD particles. The Transmission electron microscopy (TEM) analysis show the primary single particle size was ~4 nm, TEM images indicate that the primarty particles were aggregated to form secondary particles having the mean size of about 159 nm. As the concentration of the stabilizer increases, the particle size tends to decrease. Mean size determined by SdFFF, TEM, and dynamic light scattering (DLS) were 126, 159, and 152 nm, respectively. Results showed SdFFF may become a useful tool for determination of the size and its distribution of various types of inorganic particles.

• Journal of the Mineralogical Society of Korea
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• v.18 no.3 s.45
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• pp.165-181
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• 2005

The granitic rocks distributed in the southern part of the Yangsan Fault are classified into five distinct rock facies based on the field relation, petrography and geochemical characteristics. These five different rock facies can be grouped into two considering their origins. Group I, which reveals various evidences of magma mixing, includes three rock facies of granodiorite, enclave-rich porphyritic granite, and enclave-poor porphyritic granite. Group H intruding Croup I includes equigranular granite and micrographic granite with no evidence of magma mixing. It is suggested that the distinctively different trace element and isotopic chemistries between group I and II, support evolution from the different parental magma. It is suggested that the three rock facies in group I were generated by different degrees of magma mixing in addition to fractionation of plagioclase. MMEs experienced fractionation of biotite. The two facies in group H seem to have been generated from different parent magma from group I and evolved by fractionation of K-feldspar. The Rb-Sr whole-rock ages of the group I rocks yield $59.2\~58.9Ma$, and those of the group II rocks give 53. $3\~51.7Ma$, regardless of their distribution whether they occur in the eastern or western parts of the Yangsan Fault. Based on Sm-Nd isotope compositions, depleted mantle model ages $(T_2DM)$ of the group I range $0.8\~0.9Ga$, while those of the group II$0.6\~0.7Ga$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.7 no.2
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• pp.7-12
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• 1978

This experiment was conducted to fractionate the trypsin inhibitors and its heat stability of five varieties of soybean. It was observed that water extractable protein of all varieties used was fractionated into three peaks and the second peak seemed to show trypsin inhibitor activity. (TIA). The trypsin inhibitors were fractionated into four fractions-FI, FII, FIII and FIV. FIII showed the highest TIA in Suwon No. 81, Suwon No. 82 and Suwon No. 83 In the case of Kyungnam No. 3 and Suwon No. 62, the highest activity was found in FIV. When trypsin inbibitors fractionated in boiling water-bath for 20 min, the FIV showed the highest heat stability and FI was found to be the weakest.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.436-442
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• 1992

The present study was designed to analyze the lipid and fatty acid compositions of ark shell, Anadara broughtonii. The crude lipid was extracted by Bligh and Dyer's method, and then fractionated by TLC and quantitatively analyzed by TLC scanner. Lipid extracted from ark shell was fractionated into neutral and polar lipid by column chromatography with silicic acid. The fatty acid composition of lipid fractions were determined by gas liquid chromatography. Total lipid content of ark shell was 0.83% base on wet weight. The content of unsaponifiable matter was 20.19%, and iodine value was 156.13. The main components of total lipids were triglyceride, diglyceride, hydrocarbon, and sterol ester. The fatty acid composition of total lipid chiefly consisted of $C_{17 : 0}$, $C_{16 : 0}$, $C_{18 : 1}$ and $CT_{16 : 1}$. The main fatty acids of neutral lipid were $C_{16 : 0}$, $C_{18 : 1}$, $C_{22 : 1}$, $C_{18 : 0}$ and $C_{16 : 1}$. The major fatty acids of polar lipid were $C_{16 : 0}$, $C_{18 : 2}$, $C_{20 : 5}$ and $C_{22 : 6}$. In total lipid fractionation, saturated acid contents were high in all (SA>MA＞ PA), in neutral lipid fractionation, menoenoic acid contents were high in all (MA > SA> PA), and in polar lipid fractionation, saturated acid con-tents were high in all (SA> PA> MA).