• Journal of the Korean Society of Food Culture
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• v.12 no.2
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• pp.183-188
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• 1997

This study was carried out in order to analyze the changes in general compounds and sugars of traditional Korean soy sauce with varying Meju concentrations (Meju-water ratios of 1 : 4 and 1.3 : 4) and ripening periods (up to 2 years). Along with ripening period, pH decreased and titratable acidity, total acidity and crude protein contents increased, which were higher in 1.3 : 4 than in 1.4. Buffering power increased significantly with increasing ripening period. Crude fat content was higher in 1.3 : 4 than 1 : 4. Moisture content decreased and pure extract content increased significantly with increasing ripening period, which was high in 1.3 : 4. Salt contents increased with increasing ripening period, but decreasd in soy sauce ripened for 2 years. As the result of sugar analysis, reducing sugar showed slow increase with increasing ripening period. Among detected free sugars, galactose was present in the highest concentration and the rest were in the sequence of glucose, fructose. Total free sugar content was highest in soy sauce ripened for 150days in 1 : 4 and 210 days in 1.3 : 4.

• Korean Journal of Remote Sensing
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• v.21 no.4
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• pp.341-369
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• 2005

Hyperspectral images have emerged as a new and promising remote sensing data that can overcome the limitations of existing optical image data. This study was designed to provide a comprehensive review on definition, data processing methods, and applications of hyperspectral data. Various types of airborne, spaceborne, and field hyperspectral image sensors were surveyed from the available literatures and internet search. To understand the current status of hyperspectral remote sensing technology and research development, we collected several hundreds research papers from international journals (IEEE Transactions on Geoscience and Remote Sensing, International Journal of Remote Sensing, Remote Sensing of Environment and AVIRIS Workshop Proceedings), and categorized them by sensor types, data processing techniques, and applications. Although several hyperspectral sensors have been developing, AVIRIS has been a primary data source that the most hyperspectral remote sensing researches were relied on. Since hyperspectral data have very large data volume with many spectral bands, several data processing techniques that are particularly oriented to hyperspectral data have been developed. Although atmospheric correction, spectral mixture analysis, and spectral feature extraction are among those processing techniques, they are still in experimental stage and need further refinement until the fully operational adaptation. Geology and mineral exploration were major application in early stage of hyperspectral sensing because of the distinct spectral features of rock and minerals that could be easily observed with hyperspectral data. The applications of hyperspectral sensing have been expanding to vegetation, water resources, and military areas where the multispectral sensing was not very effective to extract necessary information.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.12 no.2
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• pp.20-52
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• 1999

In order to investigate the effect of Naetakchungumsankamibang(NTCGS) water extract on the skin tumor induced by 3-MCA and immunological responses in mice, the cytotoxicity against SK-MEL-2 cells and total number of tumors induced by 3-MCA were measured. The numbers of WBC, platelets and RBC, plaque forming cells, hemagglutinin titer, hemolysis titer, carbon clearance, proliferation of splenocyte by thymidine uptake assay, splenic leukocyte by FACS analysis and $TNF-{\alpha}$ were also measured for the evaluation of the immunological responses. The results were obtained as follows: 1. In cytotoxicity against SK-MEL-2 cells, concentration inhibiting cell growth up to below $20\%$ of control was recognized at 1mg/ml of NTCGS. 2. In Inhibitory effect on the skin tumor induced by 3-MCA, the results showed a strong inhibitory effect of NTCGS. 3. In hematological changes in the tumor bearing mice, the numbers of WBC decreased significantly in NTCGS treated group as compared with control. 4. In hematological changes in the tumor bearing mice, the numbers of platelets increased significantly in NTCGS treated group as compared with control. 5. In hematological changes in the tumor bearing mice, the numbers of RBC increased with no significance in NTCGS treated group as compared with control. 6. Effects of the plaque forming cells in the tumor bearing mice, NTCGS treated group exhibited a significant effect compared with control. 7. In terms of the effects on hemagglutinin titer, NTCGS treated group showed higher level than control, without significance. 8. In terms of the effects on hemolysis titer, NTCGS treated group showed higher level than control, without significance. 9. In terms of the effects on phagocytic index K in Balb/C mice, NTCGS treated group showed significant difference from control. 10. In terms of the effects on proliferation of splenocyte by thymidine uptake assay, NTCGS showed significant effect at the concentration of 0.5mg/ml. 11. In terms of the effects on splenic leukocyte of Balb/C mice by FACS analysis, NTCGS treated group showed significantly higher level of helper T cell, B cell and macrophage than in control. 12. In terms of the effects on the secretion of $TNF-{\alpha}$, the treated group showed significant effect at the concentration of 1mg/ml of NTCGS. Based on the results summarized above, NTCGS is considered to have antitumor activity and immunological responses against skin tumor, and to be usable fur the treatment.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.893-899
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• 2004

Method for sample preparation and quantitative analysis of 19 permitted and non-permitted synthetic colors in foods was developed based on reversed-phase ion-pairing high performance liquid chromatography. For color extraction of samples, deionized water was added, and pH was appropriately adjusted with 1% ammonia water. Any undissolved matters were extracted with 50% ethanol or 70% methanol. Lipid in snacks was first removed using n-hexane with centrifugation, water was added to extract colors, followed by clean-up and concentration using Sep-Pak $C_{18}$ cartridge. Recovery efficiencies at known concentrations of 19 standard food colors spiked into foods were in 90.3-97.9% range far soft drink, 79.2-101.9% for candy, 84.1-103.4% for jelly, 86.4-100.8% for chewing gum, 83.5-103.4% for ice cream, and 78.5-95.6% for snack.

• Korean Journal of Food Science and Technology
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• v.41 no.1
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• pp.82-86
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• 2009

The objective of this study was to evaluate the effect of various solvents on extraction of bioactive phenolics and to analyze the antioxidant capacity and contents of individual catechins in various grades of green teas organically grown in Boseong, Korea. The organic green teas, based on their harvest seasons, were categorized into five grades such as Woo-Jeon, Se-Jak, Jung-Jak, Dae-Jak, and coarse tea. Solvents used to extract phenolics from these teas included water at $23^{\circ}C$ and $70^{\circ}C$ as well as 80% (v/v) aqueous methanol and ethanol. In general, aqueous organic solvents of methanol and ethanol led to higher extraction yields of phenolics than water at $23^{\circ}C$ and $70^{\circ}C$. Total phenolics and antioxidant capacity of the teas extracted with the aqueous organic solvents were approximately 1.5 to 3.2 and 1.8 to 3.8 times higher than those with water at $23^{\circ}C$ and $70^{\circ}C$, respectively. Coarse tea, the lowest grade of green tea, showed approximately 30-60% lower total phenolics and antioxidant capacity compared with the higher grade ones. Reversed-phase HPLC analysis was performed quantitatively to identify individual catechins, gallic acid, and caffeine in teas extracted with 80% (v/v) aqueous methanol. Based on their dry weights, the organic green teas contained about 1.7 to 2.9% of caffeine. Content (mg/g dry weight) of tea catechins decreased in the following order: Woo-Jeon (155.4) > Se-Jak (147.7) > Jung-Jak (143.2) > coarse tea (135.1) > Dae-Jak (130.5). (-)-Epigallocatechin gallate was the most abundant among the catechins analyzed. The highest grade of green tea, Woo-Jeon, had the highest amount of (-)-epigallocatechin gallate at 77.4 mg/g dry weight. Overall, the higher grade of organic green teas tended to have the higher level of antioxidant capacity and catechins.

• Journal of Ginseng Research
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• v.32 no.4
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• pp.382-389
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• 2008

To achieve a better understanding of protective effects of water extracts of Panax ginseng against TCDD-induced toxicities, we monitored physiological and clinical changes in rat for 4 weeks after administrations of each Panax Ginseng extract or TCDD, and co-administration of the two materials. For this study, 120 male Sprague-Dawley (SD) rats weighing 190-210 g each (8 weeks old) were divided into four groups: TCDD-administered, co-administered group with TCDD and ginseng extract, ginseng extract-administered, and control group. The TCDD-administered group received single dose of TCDD in a corn oil vehicle ($25\;{\mu}g/kg$ body weight) by intraperitoneal administration on Day 1. The Panax ginseng extracts-administered group received intraperitoneally 100 mg/kg body weight every other day for one month. For the co-administered group with TCDD and ginseng extracts, Panax ginseng extracts were intraperitoneally administered to rats at 100 mg/kg body weight every other day for one month after a single intraperitoneal dose of $25\;{\mu}g$ of TCDD/kg body weight on Day 1. Panax ginseng extracts attenuated the mortality induced by TCDD administration. The extracts also slightly attenuated the TCDD-induced body weight loss. Administration of TCDD alone increased liver weight at 2, 5, and 16 days after administration of TCDD. Administration of Panax ginseng extracts rather decreased liver weight through whole the experimental period, but which was statistically insignificant. Administration of TCDD alone at $25\;{\mu}g/kg$ body weight increased both serum enzyme activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) at 32 days, indicating that liver damage occurred maximally at that time. Ginseng extract administration caused insignificant changes in serum ALT, but gradually decreased in AST as the exposure time increased. Coadministration of TCDD and ginseng extracts caused serum AST activity to significant recovery to normal value at 16 days and 32 days after exposure to TCDD. The extracts also significantly decreased the TCDD-induced ALT activity after 16 days of TCDD administration. These results suggest that Panax ginseng extracts may possess a protective effect against TCDD-induced toxicities including hepatotoxicity in rats.

• Korean Journal of Environmental Agriculture
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• v.37 no.2
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• pp.104-116
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• 2018

BACKGROUND: This experiment was conducted to establish a simultaneous analysis method for 7 kinds of herbicides in 3 different classes having similar physicochemical property as diphenyl ether(bifenox and oxyfluorfen), dinitroaniline (ethalfluralin and trifluralin), and chloroacetamide (metolachlor, pretilachlor, and thenylchlor) in crops using GC-ECD/MS. METHODS AND RESULTS: All the 7 pesticide residues were extracted with acetone from representative samples of five raw products which comprised apple, green pepper, Kimchi cabbage, hulled rice and soybean. The extract was diluted with saline water and directly partitioned into n-hexane/dichloromethane(80/20, v/v) to remove polar co-extractives in the aqueous phase. For the hulled rice and soybean samples, n-hexane/acetonitrile partition was additionally employed to remove non-polar lipids. The extract was finally purified by optimized Florisil column chromatography. The analytes were separated and quantitated by GLC with ECD using a DB-1 capillary column. Accuracy and precision of the proposed method was validated by the recovery experiment on every crop samples fortified with bifenox, ethalfluralin, metolachlor, oxyfluorfen, pretilachlor, thenylchlor, and trifluralin at 3 concentration levels per crop in each triplication. CONCLUSION: Mean recoveries of the 7 pesticide residues ranged from 75.7 to 114.8% in five representative agricultural commodities. The coefficients of variation were all less than 10%, irrespective of sample types and fortification levels. Limit of quantitation (LOQ) of the analytes were 0.004 (etahlfluralin and trifluralin), 0.008 (metolachlor and pretilachlor), 0.006 (thenylchlor), 0.002 (oxyfluorfen), and 0.02 (bifenox) mg/kg as verified by the recovery experiment. A confirmatory technique using GC/MS with selected-ion monitoring was also provided to clearly identify the suspected residues. Therefore, this analytical method was reproducible and sensitive enough to determine the residues of bifenox, ethalfluralin, metolachlor, oxyfluorfen, pretilachlor, thenylchlor, and trifluralin in agricultural commodities.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.5
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• pp.316-325
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• 2001

To develope a technique for efficiently managing fertilizer for cucumber, a quick test method to quantify nitrate content in soil solution and leaf petiole juice using a simple instrument was investigated. Among the nitrate analyzing instruments such as compact ion meter, nitrate ion meter, and test strip with reflectometer, the paper test-strip used in conjunction with a hand-held reflectometer was most closely correlated with ion chromatography method in nitrate content, and then it would be suggested with a tool that a farmer can use rapidly, conveniently and accurately for nitrate analysis in a field. Nitrate content in soil solution collected by porous cup was very variable on the lapsed time after drip irrigation and the sampling positions such as soil depth and the distance from dripper. As a result, a significant correlation between nitrate contents of soil solutions and 2M KCl soil extract was not found. However, nitrate content in soil solution extracted with a volume basis (soil:water=1:2) showed the highly significant correlation with that in 2M KCl extract. Nitrate contents of cucumber leaf petiole juices was greatly different between upper and lower leaves. Eleven to sixteen positioned-leaf would be a proper sampling position to determine nitrate content in leaf petiole for evaluating nutrient state by plant tissue analysis. From the secondary regression equations between nitrate contents of soil and petiole juice and the yield of cucumber, nitrate levels for real time diagnosis were estimated as $400mg\;l^{-1}$ soil solution by porous cup. $300mg\;l^{-1}$ in a soil volume extraction, and $1400mg\;l^{-1}$ in petiole juice from spring to summer season. In addition, the maximum yield of cucumber fruit in pot test was obtained in nitrate $1500mg\;l^{-1}$ level of petiole juice, which was similar to nitrate $1400mg\;l^{-1}$ in greenhouse trial.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.9
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• pp.1369-1379
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• 2014

The physicochemical characteristics and antioxidant activities of leaf, stem, and root of ginger (Zingiber officinale R.) were determined. Nutrient composition, reducing sugar, saponin, mineral, heavy metal, total phenolic and total flavonoid contents, and antioxidant activities based on DPPH radical scavenging and FRAP assay were measured. Catechins, gingerols, shogaols, and capsaicin compositions were also determined by HPLC. The contents of water, proteins, fats, carbohydrates, fiber, and ash from ginger root were 6.4, 6.8, 3.2, 65.4, 7.3, and 18.2%, respectively. Crude fiber contents of leaf and stem were 4~5 times higher than those of root (P<0.05), and reducing sugar content of stem was about 3 times higher than those of root. Crude saponin contents were in the order of stem

• Journal of Food Hygiene and Safety
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• v.28 no.1
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• pp.75-82
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• 2013

The simultaneous analysis and monitoring of aflatoxin $B_1$, $G_1$, $B_2$, $G_2$ and ochratoxin A in foods were carried out by HPLC with fluorescence detection. The samples were extracted with methanol/water mixture. The extract was centrifuged, diluted with phosphate buffer saline (PBS), filtered, and applied to an immunoaffinity column containing antibodies specific to both aflatoxins and ochratoxin A. After washing the column with PBS and water, the toxins were eluted from the column with methanol, and quantified by HPLC, with a run time of approximately 30 min. The recoveries for aflatoxin $B_1$, $G_1$, $B_2$, $G_2$ and ochratoxin A in foods were 78.4~101.5%, 73.3~102.1%, 81.7~106.7%, 67.0~104.6% and 78.7~120.8%, respectively. The limits of detection of aflatoxins and ochratoxin A ranged from 0.05 to $0.18{\mu}g/kg$. According to monitoring result with the established method, aflatoxin $B_1$ and ochratoxin A were found in 13 of 151 domestic commercial foods. The contamination levels were $0.32{\sim}1.80{\mu}g/kg$ for aflatoxin $B_1$ and $0.97{\mu}g/kg$ for ochratoxin A. Therefore, this study showed all commercial foods monitored were safe under the Korean standards for aflatoxins and ochratoxin A.