• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.65-69
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• 1998

To determine the amount of total bromide as 2-bromoethanol, the domestic agricultural products such as rice, barley, carrot, cucumber, apple, tomato, squash, green pepper, melon, strawberry, grape, peach, potato and celery were analyzed by GC/MSD as well as GC/ECD. The bromide was detected in most of the domestic samples and the highest bromide residue determined was 13.2 ppm in barley. The imported agricultural products including melon, kiwi, lemon, pineapple, banana, orange and grape were also analyzed for the bromide. The bromide was also detected in most of the imported ones and the highest bromide residue determined was 12.3 ppm in pineapple. In addition, the bromide residue in instant noodle spices was monitored for 4 years, recently. As results, in 1994, the bromide content was in the range of non-detection to 2.4 ppm (average 1.1 ppm) from 22 out of 24 samples; in 1995, the bromide content was 1.0 and 2.2 ppm from 2 out of 37 samples; in 1996, the bromide content was in the range of 0.7 to 37 ppm (average 12.4 ppm) from all 11 samples; and in 1997, the bromide content was in the range of 0.2 to 4.6 ppm (average 1.2 ppm) from all 59 samples. However, none of sample analyzed for the bromide was exceeded Maximum Residue Limit(s) of Korea and Codex in these survey.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.668-675
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• 1998

These surveys were conducted to check the occurrence of disease in various horticultural crops in alpine areas, especially Daekwallyong areas, Pyongchang-Gun, and Hyeongseong-Gun in Kangwon province. TuMV on Chinese cabbage was one of the most serious diseases, especially in 1994 and 1997. The incidence of soft rot and clubroot has been increased gradually. Brittle root rot on Chinese cabbage was significantly decreased. Soft rot, gray mold, downy mildew, powdery mildew, bottom rot and Alternaria leaf spot were the common diseases on most vegetable crops. Gray mold (Botrytis cinerea) on celery, cercospora leaf spot (Cercospora sp.) on melon, powdery mildew (Erysiphe cichoracearum) on lettuce, and clubroot (Plasmodiophora brassicae) on parsley are newly found in Korea. The most common and predominant diseases were viruses, especially CMV, TMV, TuMV, BBMV, and gray mold, wilts, and cercospora leaf spot on many flowers in alpine areas. Fusarium oxysporum f. sp. eustomae causing wilting on lisianthus (Eustoma grandiflorum), Turnip mosaic virus causing mosaic and color breaking on stock, Cercospora spp. causing cercospora leaf spot on various wild lily, Cladosporum echinulatum causing leaf spot on carnation, and phytoplasma causing witches' broom on statice (Limonium sinuatum) and blazing star (Liatris spp.) were newly found during these surveys in Korea.

• Journal of Applied Biological Chemistry
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• v.63 no.1
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• pp.111-116
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• 2020

Total polyphenol contents, flavonoid contents, 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activities of ethanol extracts of 20 herbal plants (sage, turmeric, mace, bayleaf, fenugreek, oregano, blackpepper, whitepepper, clove, marjoram, cinnamon, coriander, basil, dillseed, mustard, cadamon, thyme, celery, rosemary, cumin) were analyzed for the screening of high flavonoid-containing plant resource. Thyme extract, showing the highest flavonoid content and a high degree of antioxidant activity, was selected as a bioactive cosmetic material. The total polyphenols and flavonoids contents of thyme extracts were measured as 6.90 mg chlorogenic acid equivalent (CAE)/100 g and 1.71 mg naringin equivalent (NE)/100 g, respectively, and DPPH radical scavenging activities was 90%. Among the tested organic solvents, hexane gave the highest extraction yield. Thus hexane was selected as the most suitable solvent for the extraction of thyme. Response surface method was used to obtain optimized extraction conditions for thyme: reaction temperature of 35.9 ℃, raw material to hexane ratio of 1.63:25 (w/v), and reaction time of 192 min. These predicted extraction conditions was validated by a total flavonoid extraction experiment showing a value equivalent to 96.3% of the predicted total flavonoid content. It is expected that the optimized solvent extraction conditions could be used for the production of flavonoid using thyme.

• Journal of Food Hygiene and Safety
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• v.33 no.5
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• pp.339-346
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• 2018

This study was conducted to monitor the current status of pesticide residues in a total of 297 agricultural products for raw juice from January 2017 to September 2017. Pesticide residues in samples were analyzed by multiresidue method for the determination of multiclass pesticide with an aim to detect 220 pesticides using GC/ECD, GC/NPD, TOF/MS, LC/PDA, LC/FLD, and LC/MS-MS. The analysis revealed the presence of nine pesticides in 14 samples. The detected pesticides were chlorpyrifos, cyflufenamid, chlorothalonil, pendimethalin, azoxystrobin, pyridalyl, imazalil, fludioxonil and procymidone. The kinds of detected crops were mandarin, carrot, apple, celery, chicory, orange and grape. Risk assessment evaluated human health exposure with the ratio of EDI (Estimated daily intake) to ADI (Acceptable daily intake) of pesticides detected and the range of %ADI (the ratio of EDI to ADI) values was 0.0011~6.7087% and safety level.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.303-310
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• 2002

An optimization for fermentation processes to make lactic acid juice with extracts from apples, carrots, celery, watercress, jujube and lycii (3 : 3 : 1 : 1/2 : 1 : 1/2) using co-cultures of Leuconostoc mesenteroides, Lactococcus lactis and Lactobacillus cellobiosus isolated from Dongchimi had been investigated on the emphasis of composition of sugars and sodium chloride at various temperatures. The concentration of sugars less than 25% and salt less than 0.8% did not affect remarkably the cell growth of lactic acid bacteria and acid formation during fermentation. The fermenting juice showed increases in the population of lactic acid bacteria and acidity, and decreases in population of coliform bacteria and sugar concentration with high cultural temperature. At $25^{\circ}C$ viscous substance was not formed as it had at $15^{\circ}C$. The optimum composition, based on the sensory evaluation, was determined to be oligosaccharide and 0.2% for sodium chloride. It took 3 days to produce the most preferable juice of pH 3.62 at $25^{\circ}C$. At the optimal state the fermented juice showed viable cell counts (cfu/mL) of exponential numbers 8 for lactic acid bacteria and 4 for yeast. Coliform bacteria which had been $5.6{\times}10^2\;cfu/mL$ at the beginning of fermentation were not detected.

• Journal of The Korean Association For Science Education
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• v.24 no.5
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• pp.1018-1027
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• 2004

The purpose of this study was to identify and compare the types of scientific questions which were generated by elementary students and preservice teachers on the tasks of scientific observation. To identify the types of scientific questions, 4 observing tasks, dry grapes contained in soda pop, candlelight, celery, and a rock were administered to 40 sixth elementary students and 20 elementary preservice teachers. And then, the types and frequency of scientific questions generated by them were compared. The results showed that the types of scientific questions were classified into conjectural questions, causal questions, predictive questions, methodical questions and applicative questions. Further more, subordinate questions to the above questions were classified into object exploration questions and object verification questions, explicans exploration questions and explicans verification questions, result exploration questions and result verification questions, example exploration questions and example verification questions. Subordinate questions did not come out from the methodical questions. The types of scientific questions generated by elementary students and preservice teachers were identical, however, there were differences in frequency. This study supports that elementary students also have cognitive capability to generate various scientific questions. The results of this study may be used as a teaching strategy for the guidance of the direction and the method of scientific inquiry.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.453-462
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• 2011

This study was carried out to survey the residual characteristics of pesticides and assess their safety. Nineteen agricultural commodities, collected from wholesale and traditional markets in Cheongju. Nineteen agricultural commodities including perilla leaves were collected from the markets on October 29th, 2010. Total 240 pesticides which can be analyzed by multiresidue analysis method by GLC and HPLC were monitored and the pesticides detected were confirmed by GC-MSD and LC-MS. Five pesticides, alachlor, bifenthrin, endosulfan, procymidone and triflumizole, were detected from five samples, such as welsh onion, leek and celery in case of wholesale market and perilla leaves and welsh onion in case of traditional market. Detection rate of 13.2% was obtained as a result of pesticide analysis but 2.6% of the pesticides detected exceeded their maximum residue limits. The estimated daily intakes (EDIs) and maximum permissible intakes (MPIs) of the pesticides detected were less than 26% and 0.05% of their acceptable daily intakes (ADIs) respectively, representing that residue levels of the pesticides detected would be safe.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.389-403
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• 2016

Sugar beet nematode (Heterodera schachtii Schmidt) was first detected in 2011, in Chinese cabbage grown in the highland areas of Korea. Chemical control of the nematode by nematicides is not feasible due to its cyst-forming characteristics; therefore, the cultivation of non-host crops is a preferable alternative to utilize nematode-infected fields. In this study, a total of 276 plant cultivars belonging to 18 different families were screened to evaluate their resistance to the nematode. Based on the number of cysts formed following nematode inoculation, the tested crops were classified into 3 levels: susceptible, moderately susceptible, and resistant/immune. Among the 276 cultivars tested, 106 cultivars were susceptible, 40 cultivars were moderately susceptible, and 130 cultivars were resistant/immune. Among the resistant/immune cultivars, cyst formation was not observed on eggplant, tomato, lettuce, perilla, carrot, celery, watermelon, oriental melon, cucumber, pumpkin, chives, onion, welsh onion, balloon flower roots, deodeok (Codonopsis lanceolata), Jandae (Adenophora triphylla), and bean. Therefore, these plants are regarded as immune to the cyst nematode. However, many crops belonging to Solanaceae, Asteraceae, Chenopodiaceae, and Poaceae families showed moderate susceptibility or immunity, depending on the crop or cultivar. This study provides a basis for alternative crop recommendations for sugar beet nematode cyst-infected farms in Chinese cabbage production areas.

• Journal of Food Hygiene and Safety
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• v.37 no.1
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• pp.21-28
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• 2022

In this study, a new lactic acid bacterium (LAB) that could produce gamma-aminobutyric acid (GABA) was isolated from Oenanthe javanica (water celery) and identified as an Enteroccoccus casseliflavus strain. Until recently, there have been many studies on the gamma-aminobutyric acid producing lactic acid bacterium, as well as on some lactic acid bacterium in Enteroococcs genus, but none on the species E. casseliflavus. Therefore, in the purpose of finding the optimal conditions for GABA production of E. casseliflavus PL05, the effects of several conditions including the type of mediums, growth temperatures, initial pH, growth time, L-mono sodium glutamate (MSG) concentration, and carbon source were tested. The study revealed that the PL05 strain grew better in the Brain Heart Infusion (BHI) medium than in the Man, Rogosa, and Sharpe (MRS) or Tryptic Soy Broth (TSB) medium. Also, similar results were obtained with GABA production conditions. As a result of analysis on the GABA production yield by concentration of MSG, a GABA substrate, the highest production was found at 7% of MSG concentration. However, since similar level of production was found at 5%, it is considered to be more efficient to use 5% MSG concentration. The analysis on the growth and GABA production yield by carbon sources showed the highest results when maltose was used. From the final test under the optimal conditions found, 140.06±0.71 mM of GABA was produced over 24 hours with the conversion rate of 78.95%. Lastly, from the sensitivity analysis on the 10 different antibiotics, including vancomycin, it was found that there were not confirmed cases of resistance.

• Journal of Industrial Convergence
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• v.21 no.6
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• pp.37-42
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• 2023

This study aimed to examine the safety of HemoHIM, a dietary supplement containing methoxsalen. HemoHIM is a dietary supplement marketed globally, and a competitor to ginseng. It has been reported to contain methoxsalen, a plant extract for treating psoriasis and vitiligo. Methoxsalen is known to cause hepatotoxicity, but most of the cases has been reported from ingestion as a drug, not a food. There are no reports of hepatotoxicity from the consumption derived from natural products such as Angelica gigas, Cnidium officinale, and Paeonia lactiflora, which are the main ingredients in the HemoHIM. However, a recent case of acute hepatitis was reported in Hong-Kong after ingestion of HemoHIM. It is difficult to conclude that hepatitis was caused by HemoHIM, because there was no check of co-occurring medications with a higher risk of hepatotoxicity, no description of the progress, no quantitative comparison of methoxsalen in HemoHIM to it in common foods such as carrots and celery, and no description of the patient's underlying diseases. On the other hand, there was a study that suggest hemoHIM is safe, and that study had adequate number of subjects even though more studies are needed to ensure safety.