• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.115-123
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• 2019

An analytical method was developed for the determination of fenpropimorph, a morpholine fungicide, in hulled rice, potato, soybean, mandarin and green pepper using QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) sample preparation and LC-MS/MS (liquid chromatography-tandem mass spectrometry). The QuEChERS extraction was performed with acetonitrile followed by addition of anhydrous magnesium sulfate and sodium chloride. After centrifugation, d-SPE (dispersive solid phase extraction) cleanup was conducted using anhydrous magnesium sulfate, primary secondary amine sorbents and graphitized carbon black. The matrix-matched calibration curves were constructed using seven concentration levels, from 0.0025 to 0.25 mg/kg, and their correlation coefficient ($R^2$) of five agricultural products were higher than 0.9899. The limits of detection (LOD) and quantification (LOQ) were 0.001 and 0.0025 mg/kg, respectively, and the limits of quantification for the analytical method were 0.01 mg/kg. Average recoveries spiked at three levels (LOQ, $LOQ{\times}10$, $LOQ{\times}50$, n=5) and were in the range of 90.9~110.5% with associated relative standard deviation values less than 5.7%. As a result of the inter-laboratory validation, the average recoveries between the two laboratories were 88.6~101.4% and the coefficient of variation was also below 15%. All optimized results were satisfied the criteria ranges requested in the Codex guidelines and Food Safety Evaluation Department guidelines. This study could serve as a reference for safety management relative to fenpropimorph residues in imported and domestic agricultural products.

• Toxicological Research
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• v.28 no.1
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• pp.39-49
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• 2012

We investigated the effect of zinc on the formation of colonic aberrant crypt foci induced by azoxymethane (AOM) followed by dextran sodium sulfate (DSS) in mice with high iron diet (HFe; 450 ppm iron). Sixweek old ICR mice were fed on high iron diets with combination of three different levels of zinc in diets, low-zinc (LZn; 0.01 ppm), medium-zinc (MZn; 0.1 ppm), and high-zinc (HZn; 1 ppm) for 12 weeks. Animals were received weekly intraperitoneal injections of AOM (10 mg/kg B.W. in saline) for 3 weeks followed by 2% DSS (molecular weight 36,000~50,000) in the drinking water for a week. To confirm the iron storage in the body, the hepatic iron concentration has been determine chemically and compared with histological assessment visualized by Prussian blue reaction. Aberrant crypt (AC) and aberrant crypt foci (ACF) were analyzed in the colonic mucosa of mouse fed high dietary iron. Superoxide dismutase (SOD) activity and thiobarbituric acid-reactive substances (TBARS) level were also investigated. Apoptosis in the preneoplastic lesion was determined by terminal deoxynucleotidyl transferase-mediated dUTP nickend labeling (TUNEL). In addition, immunohistochemistry of ${\beta}$-catenin was also performed on the mucous membrane of colon. The number of large ACF (${\geq}4$ AC/ACF), which possess greater tumorigenic potential, was significantly lower in MZn and HZn groups compared with LZn group. Cytosolic SOD activity in the liver was significantly higher in HZn group compared with LZn group. Hepatic MDA level was decreased significantly in HZn group compared with MZn and LZn groups. Apoptotic index was significantly higher in HZn group. Taken together, these findings indicate that dietary zinc might exert a protective effect against colonic preneoplastic lesion induced by AOM/DSS in ICR mice with high iron status, and suggest that dietary supplement of zinc might play a role in suppressing colon carcinogenesis in mice.

• Horticultural Science & Technology
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• v.34 no.6
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• pp.924-939
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• 2016

The great economic losses caused by Cucumber mosaic virus (CMV) infection of peppers has led to the development of genetically modified (GM) CMV-resistant peppers. We developed virus-resistant pepper plants using Agrobacterium tumefaciens -mediated transformation. The expressed recombinant protein was purified using nickel-nitrilotriacetic acid resin and immunoaffinity chromatography, and purity was assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Immunoblot analysis revealed the purified CMV coat protein (CMV-CP) had a molecular mass of 25 kDa. After in-gel digestion and desalting, the internal peptide fragments of CMV-CP were sequenced by matrix-assisted laser desorption/ionization-time of flight. Most GM pepper and Escherichia coli BL21 internal peptides had identical peptide sequences and contained 137 of 183 whole peptides in CMV-CP. A quantitative enzyme-linked immunosorbent assay was performed to detect CMV-resistant GM peppers. We also provide basic information about the expressed protein in GM peppers for further safety assessment. The contents of soluble protein and CMV-CP were measured in GM and control peppers cultivated in three different areas of Korea. Statistical significance in terms of cultivation areas, harvest times, generations, and plant tissue origin were determined based on a P value of 0.05. The highest amount of CMV-CP was detected at the seedling stage from plant grown in each region. T3 and T5 showed significantly different levels of CMV-CP from T4 in leaves in the whorl stage. No statistical differences were observed among GM peppers at different stages of maturity in any cultivation area. The results from this study contribute to the safety evaluation of newly designed CMV-resistant GM peppers and provide a standard against which to compare other virus-resistant GM peppers.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.7-10
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• 2009

An analytical method for the determination of flumequine in meats was developed and validated using high-performance liquid chromatography with fluorescence detection. The samples were mixed with sodium sulfate and extracted with ethyl acetate. After clean-up, the residues were dissolved in mobile phase. The calibration curves showed high linearity ($r^2$=0.9979) within the concentration range of 0.1-1.0 mg/kg. The limit of detection and limit of quantification were validated at 0.005 and 0.017 mg/kg, respectively. The recoveries in fortified meats ranged from 90.8 to 101.1%. The method was then validated in correspondence with the CODEX guidelines for flumequine residue in meats. Herein we monitored 150 samples of meats that were purchased in Korea (Seoul, Busan, Daegu, Daejeon, and Gwangju). Among the tested samples, flumequine was detected in 1 of beef and 1 of pork at levels in the range of 0.048-0.080 mg/kg. Overall, the flumequine residues in the tested samples were within the Maximun residue limit.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.3
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• pp.193-201
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• 2014

This study was conducted to examine the effects of defaunation (removal of live protozoa) on fermentation characteristics, degradation of ryegrass hay and $CH_4$ (methane) production by rumen microbes when incubated with plant oils (SO, sunflower oil and LO, linseed oil) in vitro. Sodium lauryl sulfate (0.000375 g/ml) as a defaunation reagent was added into the culture solution and incubated anaerobically up to 24 h at $39^{\circ}C$. pH from defaunation was increased for all treatments from 6 h incubation times (p<0.01-0.001) compared with those from fauantion. Concentration of ammonia-N from defaunation is higher than that from faunation at 3 h (p<0.001), 12 h (p<0.05) and 24 h (p<0.001) incubation times. Defaunation decreased (p<0.01-0.001) total volatile fatty acid concentration at all incubation times. Molar proportions of $C_2$ (acetate, p<0.05-0.001) and butyrate (p<0.01-0.001) were also decreased by defaunation at all incubation times. Molar proportion of $C_3$ (propionate), however, was increased by defaunation at all incubation times (p<0.001). Thus the rate of $C_2$ to $C_3$ was decreased by defaunation at all incubation times (p<0.001). Defaunation decreased ED (effective degradability) of dry matter (p<0.001) and ED of neutral detergent fiber (p<0.001) of ryegrass hay. Defaunation decreased total gas, $CH_4$ production, $CH_4$ % in total gas and $CH_4/CO_2$ at all incubation times (p<0.001). Oil supplementation decreased total gas (p<0.05-0.001), $CH_4$ production (p<0.001) and $CH_4$ % in total gas (p<0.001) compared with control at all incubation times. The result of this study showed that defaunation combined with oil supplementation may cause an alteration of microbial communities and further medicate the fermentation pattern, resulting in both reduction of degradation of ryegrass hay and $CH_4$ production. No difference, however, was observed in all the examinations between SO and LO.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.5
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• pp.736-742
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• 2017

Objective: Experiments were conducted to clone the sequence of Wild Argali short palate, lung and nasal epithelium clone 1 (SPLUNC1) cDNA, and to lay the foundation for further study the biological function of Wild Argali SPLUNC1. Methods: The complete sequence of Wild Argali SPLUNC1 cDNA was generated by rapid amplification of cDNA ends. The entire coding sequence was inserted into the pPIC9K vector and expressed in Pichia pastoris (P. pastoris) GS115. The recombinant SPLUNC1 protein was detected by Western blot and purified by $Ni^{2+}$ chelate affinity chromatography. The test of effect of the protein on Mycoplasma ovipneumoniae (MO) was performed with real-time polymerase chain reaction. Results: The Wild Argali SPLUNC1 cDNA was 1,076 bp with an open reading frame of 768 bp, which encoded a 26.49 kDa protein composed of 255 amino acids. Its amino acid sequence shared 98.4%, 96.9%, 94.5%, 90.2%, 80.8%, 78.4%, 78.3%, 72.5%, 72.3%, 68.8% identity with those of SPLUNC1 cDNA from Ovis aries (accession no. NP_001288334.1), Capra hircus (accession no. XP_005688516.1), Pantholops hodgsonii (accession no. XP_005979709.1), Bos taurus (accession no. NP_776851.1), Felis catus (accession no. XP_006929910.1), Homo sapiens (accession no. NP_001230122.1), Sus scrofa (accession no. NP_001005727.1), Chinchilla lanigera (accession no. NP_001269294.1), Mus musculus (accession no. NP_035256.2), and Rattus norvegicus (accession no. NP_742028.1), respectively. The recombinant protein corresponded to the expected molecular mass of 25.47 kDa as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and it was detected in the supernatant of P. pastoris, and it could be purified. The results from the test of inhibition effect of argali recombinant SPLUNC1 protein on MO showed that the product could inhibit MO very well (p<0.01). Conclusion: The amino acid sequence of Wild Argali SPLUNC1 was different from other organisms. The recombinant SPLUNC1 protein has good biological activity.

• Korean Journal of Veterinary Research
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• v.41 no.1
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• pp.21-28
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• 2001

The protein of the bovine, horse and dog erythrocyte membrane were analyzed by polyacrylamide gel eletrophoresis in sodium dodecyl sulfate and their relation to the sedimentation rate of animal erythrocytes were investigated by treating the erythrocytes with proteinases such as trypsin and chymotrypsin. Protein content in erythrocyte membrane was in human, in Jindo dog, in cattle and in horse, showing similar in among. The erythrocyte sedimentation rates bovine erythrocytes from Hostein and Korean native cattle were very slow compared with the human one(1/7 as slow as the human one) as reported previously. Although the general protein profiles of the bovine erythrocyte membranes were almost similar to that of human, bovine erythrocyte membranes showed one additional protein band, called band Q in this study, which migrated electrophoretically to the mid-position between band 2 and band 3 in human erythrocyte membranes. The erythrocyte sedimentation of race horse were very fast compared with the human one are reported previously. Although the general protein profiles of the race horse erythrocyte membranes were almost similar to that of human, band 3 content was showing higher in race horse(34.7%) than in human(25.3%). The general protein profile of the Jindo dog erythrocyte membrane was almost similar to the human patterns, Jindo dog erythrocyte membranes showed one absent protein band. It was band 7. The glycoprotein profiles of the bovine erythrocyte membranes revealed by periodic acid-Schiff(PAS) stain showed a marked difference from that of human. The PAS-1(glycophorin) and PAS-2(sialoglycoprotein) present in human erythrocyte membrane were almost absent from the bovine erythrocyte membranes showed a strong PAS-positive band near the origin of the electraphorograms, which is named as PAS-B in this study. The PAS-1 and PAS-2 present in human erythrocyte membrane were almost absent from race horse erythrocyte membranes, but PAS-2 was more in only race horse from that of human. The PAS-1 and PAS-2 were absolutely absent from the Jindo dog erythrocyte membrane. These results suggest the slow sedimentation rate of bovine erythrocytes is due in part to the presence of band Q protein fraction and PAS-B glycoprotein in the bovine erythrocytes, and that the fast sedimentation rate of race horse erythrocyte is due in part to the presence of more band 3 protein fraction and PAS-E glycoproteins in the race horse erythrocytes.

• Parasites, Hosts and Diseases
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• v.27 no.1
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• pp.9-14
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• 1989

Enzyme-linked immunoelectrotransfer blot (EITB) using crude worm antigen of adult Paragonimus westermani was performed for human patients sera to identify the species-specific components. Crude antigen was obtained by homogenizing and centrifuging 24-week old adult worms at 10,000 rpm for 60 minutes in phosphate buffered saline (PBS, PH 7.2) containing: Phenyl methyl sulfonyl auoride (PMSF). Gradient sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE) was performed and blotted electrophoretically onto a sheet of nitrocellulose paper. The sheet was cut into strips and exposed to sera diluted 1 : 200 with PBS. SDS-PAGE showed 26 protein bands ranging 229 to 10 kDa. Of them 229, 91, 60, 50, 35∼31, 27, 25, 21, 17, 11 and 10 kDa components showed positive reaction with serum antibody of patients with p. westermani. Sera of patients infected with Clcnorchis sinensis reacted with 35∼31, 19, and 11 kDa bands. Human sera from cysticercosis and diphyllobothriasis cases showed non-specific cross reactions with 229, 35∼31, 27, 25 and 17kDa bands. Protein bands of 91, 60, 21 and 10kDa showed strong positive reaction without cross reactions with sera from other helminthic infections.

• The korean journal of orthodontics
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• v.20 no.3 s.32
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• pp.447-462
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• 1990

The objective of this experiment is to observe structural differences in the othodontic movement of vital (control group) and devitalized (experimental group) teeth in the mongrel dogs. The 5 utilized dogs in this experiment were approximately 1 year of age and their average weight was about 12 Kg. Endodontic therapy was performed on the 2nd premolars in upper & lower jaws of each animal under the general anesthesia by intravascular injection of 25mg/kg of pentobarbital sodium. The canals of the teeth were obturated by using gutta percha in conjunction with root canal sealer (AH26 Densply). One of the roots in the 2nd premolars was hemisected to make an extraction space for the devitalized teeth to be moved. The edgewise technique was employed for the movement of the teeth. Orthodontic models and intraoral roentgenograms were taken before and after orthodontic tooth movement. The open coil springs (.010 x .040) were used at interbraket space in order to provide equal forces (75gm) between the teeth in each arch wire. After 13 weeks of active orthodontic tooth movement, dogs were sacrified and the experimental results w ere examined through the intraoral radiography, microscopic examination and scanning electromicroscopic examination at the root sulfate. From the results of the study, the following conclusions may be drawn: The root resolution and cemental deposition were observed within the pressure and tension site in both group. 2. The root resorbed lacunae were observed in the cementum and/or into the dentin in both group. 3. The prominent osteoblastic activities were observed on the alveolar margin in the tension site in both group. 4. A few of blood vessels were observed in the pressure site, but also lots of blood vessels were observed in the tension site especially in the periphery of the alveolar bone in both group. 5. In the pressure site, resorbed lacunae were formed with deep and narrow cavity in the control group; the shallow and wide cavity in the experimental group. 6. In the pressure site, the repaired cementum or cementoid tissue was lined on cementum in the experimental group, but not in the control group. 7. There was no significant difference between external root resolution of endodontically and vital teeth when both were subjected to orthodontic forces.

• Current Research on Agriculture and Life Sciences
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• v.11
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• pp.121-132
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• 1993

This study was carried out to research the effect of the chemotaxis of Bradyrhizobium japonicum KCTC 2422 and its mutant toward soybean root exudate and to elucidate the effect of the lectin of host specificity (Host Recognition) in soybean-Bradyrhizobium symbiosis. The results obtained were as follows: The homogeneities of the purified lectins from soybean and pea seed was ascertained chromatographically and electrophoretically. Gel electrophoresis of soybean lectin in the presence of sodium dodecyl sulfate appeared a single protein band, whereas pea lectin appeared two protein bands. Soybean lectin from 2 cultivars formed immunoprecipitin arcs at same position with anti-soybean lectin rabbit IgG, but pea lectin did not form immunoprecipitin lines with anti-soybean lectin rabbit IgG. Chemotactic responses of KCTC 2422, LPN-100 and LCR-101 toward proline in capillary assays were 3.1, 1.3 and 1.0-fold above background, respectively. The chemotactic responses of KCTC 2422, LPN-100, and LCR-101 toward Paldal crude root exudate in capillary assays were 3.5, 1.4 and 1.4-fold above background, respectively. The present work shows that B. japonicum and its mutants are capable of very different responses toward root exudate fraction. The chemotactic responses of KCTC 2422 was most with neutral fraction, least with anionic fraction and intermediate with cationic fraction. The nitrogenase activity of soybean nodule was shown in 15days after inoculation with LCR-101. However, we couldn't find out the nodules when soybean was inoculated with LPN-100. From these result we can suppose that the chemotaxis of Bradyrhizobium plays inportant the role of forming the nodule (host recognition) in the soybean-B. japonicum symbiosis.